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Diffstat (limited to 'tools/profiler/core/platform.cpp')
| -rw-r--r-- | tools/profiler/core/platform.cpp | 7246 |
1 files changed, 7246 insertions, 0 deletions
diff --git a/tools/profiler/core/platform.cpp b/tools/profiler/core/platform.cpp new file mode 100644 index 0000000000..e4af84ed4c --- /dev/null +++ b/tools/profiler/core/platform.cpp @@ -0,0 +1,7246 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +// There are three kinds of samples done by the profiler. +// +// - A "periodic" sample is the most complex kind. It is done in response to a +// timer while the profiler is active. It involves writing a stack trace plus +// a variety of other values (memory measurements, responsiveness +// measurements, markers, etc.) into the main ProfileBuffer. The sampling is +// done from off-thread, and so SuspendAndSampleAndResumeThread() is used to +// get the register values. +// +// - A "synchronous" sample is a simpler kind. It is done in response to an API +// call (profiler_get_backtrace()). It involves writing a stack trace and +// little else into a temporary ProfileBuffer, and wrapping that up in a +// ProfilerBacktrace that can be subsequently used in a marker. The sampling +// is done on-thread, and so REGISTERS_SYNC_POPULATE() is used to get the +// register values. +// +// - A "backtrace" sample is the simplest kind. It is done in response to an +// API call (profiler_suspend_and_sample_thread()). It involves getting a +// stack trace via a ProfilerStackCollector; it does not write to a +// ProfileBuffer. The sampling is done from off-thread, and so uses +// SuspendAndSampleAndResumeThread() to get the register values. + +#include "platform.h" + +#include "GeckoProfiler.h" +#include "GeckoProfilerReporter.h" +#include "PageInformation.h" +#include "PowerCounters.h" +#include "ProfileBuffer.h" +#include "ProfiledThreadData.h" +#include "ProfilerBacktrace.h" +#include "ProfilerChild.h" +#include "ProfilerCodeAddressService.h" +#include "ProfilerControl.h" +#include "ProfilerCPUFreq.h" +#include "ProfilerIOInterposeObserver.h" +#include "ProfilerParent.h" +#include "ProfilerRustBindings.h" +#include "mozilla/MozPromise.h" +#include "shared-libraries.h" +#include "VTuneProfiler.h" +#include "ETWTools.h" + +#include "js/ProfilingFrameIterator.h" +#include "memory_hooks.h" +#include "mozilla/ArrayUtils.h" +#include "mozilla/AutoProfilerLabel.h" +#include "mozilla/BaseAndGeckoProfilerDetail.h" +#include "mozilla/ExtensionPolicyService.h" +#include "mozilla/extensions/WebExtensionPolicy.h" +#include "mozilla/glean/GleanMetrics.h" +#include "mozilla/Monitor.h" +#include "mozilla/Preferences.h" +#include "mozilla/Printf.h" +#include "mozilla/ProcInfo.h" +#include "mozilla/ProfilerBufferSize.h" +#include "mozilla/ProfileBufferChunkManagerSingle.h" +#include "mozilla/ProfileBufferChunkManagerWithLocalLimit.h" +#include "mozilla/ProfileChunkedBuffer.h" +#include "mozilla/ProfilerBandwidthCounter.h" +#include "mozilla/SchedulerGroup.h" +#include "mozilla/Services.h" +#include "mozilla/StackWalk.h" +#include "mozilla/Try.h" +#ifdef XP_WIN +# include "mozilla/NativeNt.h" +# include "mozilla/StackWalkThread.h" +# include "mozilla/WindowsStackWalkInitialization.h" +#endif +#include "mozilla/StaticPtr.h" +#include "mozilla/ThreadLocal.h" +#include "mozilla/TimeStamp.h" +#include "mozilla/UniquePtr.h" +#include "mozilla/Vector.h" +#include "BaseProfiler.h" +#include "nsDirectoryServiceDefs.h" +#include "nsDirectoryServiceUtils.h" +#include "nsIDocShell.h" +#include "nsIHttpProtocolHandler.h" +#include "nsIObserverService.h" +#include "nsIPropertyBag2.h" +#include "nsIXULAppInfo.h" +#include "nsIXULRuntime.h" +#include "nsJSPrincipals.h" +#include "nsMemoryReporterManager.h" +#include "nsPIDOMWindow.h" +#include "nsProfilerStartParams.h" +#include "nsScriptSecurityManager.h" +#include "nsSystemInfo.h" +#include "nsThreadUtils.h" +#include "nsXULAppAPI.h" +#include "Tracing.h" +#include "prdtoa.h" +#include "prtime.h" + +#include <algorithm> +#include <errno.h> +#include <fstream> +#include <ostream> +#include <set> +#include <sstream> +#include <string_view> +#include <type_traits> + +#if defined(GP_OS_android) +# include "JavaExceptions.h" +# include "mozilla/java/GeckoJavaSamplerNatives.h" +# include "mozilla/jni/Refs.h" +#endif + +#if defined(GP_OS_darwin) +# include "nsCocoaFeatures.h" +#endif + +#if defined(GP_PLAT_amd64_darwin) +# include <cpuid.h> +#endif + +#if defined(GP_OS_windows) +# include <processthreadsapi.h> + +// GetThreadInformation is not available on Windows 7. +WINBASEAPI +BOOL WINAPI GetThreadInformation( + _In_ HANDLE hThread, _In_ THREAD_INFORMATION_CLASS ThreadInformationClass, + _Out_writes_bytes_(ThreadInformationSize) LPVOID ThreadInformation, + _In_ DWORD ThreadInformationSize); + +#endif + +// Win32 builds always have frame pointers, so FramePointerStackWalk() always +// works. +#if defined(GP_PLAT_x86_windows) +# define HAVE_NATIVE_UNWIND +# define USE_FRAME_POINTER_STACK_WALK +#endif + +// Win64 builds always omit frame pointers, so we use the slower +// MozStackWalk(), which works in that case. +#if defined(GP_PLAT_amd64_windows) +# define HAVE_NATIVE_UNWIND +# define USE_MOZ_STACK_WALK +#endif + +// AArch64 Win64 doesn't seem to use frame pointers, so we use the slower +// MozStackWalk(). +#if defined(GP_PLAT_arm64_windows) +# define HAVE_NATIVE_UNWIND +# define USE_MOZ_STACK_WALK +#endif + +// Mac builds use FramePointerStackWalk(). Even if we build without +// frame pointers, we'll still get useful stacks in system libraries +// because those always have frame pointers. +// We don't use MozStackWalk() on Mac. +#if defined(GP_OS_darwin) +# define HAVE_NATIVE_UNWIND +# define USE_FRAME_POINTER_STACK_WALK +#endif + +// Android builds use the ARM Exception Handling ABI to unwind. +#if defined(GP_PLAT_arm_linux) || defined(GP_PLAT_arm_android) +# define HAVE_NATIVE_UNWIND +# define USE_EHABI_STACKWALK +# include "EHABIStackWalk.h" +#endif + +// Linux/BSD builds use LUL, which uses DWARF info to unwind stacks. +#if defined(GP_PLAT_amd64_linux) || defined(GP_PLAT_x86_linux) || \ + defined(GP_PLAT_amd64_android) || defined(GP_PLAT_x86_android) || \ + defined(GP_PLAT_mips64_linux) || defined(GP_PLAT_arm64_linux) || \ + defined(GP_PLAT_arm64_android) || defined(GP_PLAT_amd64_freebsd) || \ + defined(GP_PLAT_arm64_freebsd) +# define HAVE_NATIVE_UNWIND +# define USE_LUL_STACKWALK +# include "lul/LulMain.h" +# include "lul/platform-linux-lul.h" + +// On linux we use LUL for periodic samples and synchronous samples, but we use +// FramePointerStackWalk for backtrace samples when MOZ_PROFILING is enabled. +// (See the comment at the top of the file for a definition of +// periodic/synchronous/backtrace.). +// +// FramePointerStackWalk can produce incomplete stacks when the current entry is +// in a shared library without framepointers, however LUL can take a long time +// to initialize, which is undesirable for consumers of +// profiler_suspend_and_sample_thread like the Background Hang Reporter. +# if defined(MOZ_PROFILING) +# define USE_FRAME_POINTER_STACK_WALK +# endif +#endif + +// We can only stackwalk without expensive initialization on platforms which +// support FramePointerStackWalk or MozStackWalk. LUL Stackwalking requires +// initializing LUL, and EHABIStackWalk requires initializing EHABI, both of +// which can be expensive. +#if defined(USE_FRAME_POINTER_STACK_WALK) || defined(USE_MOZ_STACK_WALK) +# define HAVE_FASTINIT_NATIVE_UNWIND +#endif + +#ifdef MOZ_VALGRIND +# include <valgrind/memcheck.h> +#else +# define VALGRIND_MAKE_MEM_DEFINED(_addr, _len) ((void)0) +#endif + +#if defined(GP_OS_linux) || defined(GP_OS_android) || defined(GP_OS_freebsd) +# include <ucontext.h> +#endif + +using namespace mozilla; +using namespace mozilla::literals::ProportionValue_literals; + +using mozilla::profiler::detail::RacyFeatures; +using ThreadRegistration = mozilla::profiler::ThreadRegistration; +using ThreadRegistrationInfo = mozilla::profiler::ThreadRegistrationInfo; +using ThreadRegistry = mozilla::profiler::ThreadRegistry; + +LazyLogModule gProfilerLog("prof"); + +ProfileChunkedBuffer& profiler_get_core_buffer() { + // Defer to the Base Profiler in mozglue to create the core buffer if needed, + // and keep a reference here, for quick access in xul. + static ProfileChunkedBuffer& sProfileChunkedBuffer = + baseprofiler::profiler_get_core_buffer(); + return sProfileChunkedBuffer; +} + +mozilla::Atomic<int, mozilla::MemoryOrdering::Relaxed> gSkipSampling; + +#if defined(GP_OS_android) +class GeckoJavaSampler + : public java::GeckoJavaSampler::Natives<GeckoJavaSampler> { + private: + GeckoJavaSampler(); + + public: + static double GetProfilerTime() { + if (!profiler_is_active()) { + return 0.0; + } + return profiler_time(); + }; + + static void JavaStringArrayToCharArray(jni::ObjectArray::Param& aJavaArray, + Vector<const char*>& aCharArray, + JNIEnv* aJni) { + int arraySize = aJavaArray->Length(); + for (int i = 0; i < arraySize; i++) { + jstring javaString = + (jstring)(aJni->GetObjectArrayElement(aJavaArray.Get(), i)); + const char* filterString = aJni->GetStringUTFChars(javaString, 0); + // FIXME. These strings are leaked. + MOZ_RELEASE_ASSERT(aCharArray.append(filterString)); + } + } + + static void StartProfiler(jni::ObjectArray::Param aFiltersArray, + jni::ObjectArray::Param aFeaturesArray) { + JNIEnv* jni = jni::GetEnvForThread(); + Vector<const char*> filtersTemp; + Vector<const char*> featureStringArray; + + JavaStringArrayToCharArray(aFiltersArray, filtersTemp, jni); + JavaStringArrayToCharArray(aFeaturesArray, featureStringArray, jni); + + uint32_t features = 0; + features = ParseFeaturesFromStringArray(featureStringArray.begin(), + featureStringArray.length()); + + // 128 * 1024 * 1024 is the entries preset that is given in + // devtools/client/performance-new/shared/background.jsm.js + profiler_start(PowerOfTwo32(128 * 1024 * 1024), 5.0, features, + filtersTemp.begin(), filtersTemp.length(), 0, Nothing()); + } + + static void StopProfiler(jni::Object::Param aGeckoResult) { + auto result = java::GeckoResult::LocalRef(aGeckoResult); + profiler_pause(); + nsCOMPtr<nsIProfiler> nsProfiler( + do_GetService("@mozilla.org/tools/profiler;1")); + nsProfiler->GetProfileDataAsGzippedArrayBufferAndroid(0)->Then( + GetMainThreadSerialEventTarget(), __func__, + [result](FallibleTArray<uint8_t> compressedProfile) { + result->Complete(jni::ByteArray::New( + reinterpret_cast<const int8_t*>(compressedProfile.Elements()), + compressedProfile.Length())); + + // Done with capturing a profile. Stop the profiler. + profiler_stop(); + }, + [result](nsresult aRv) { + char errorString[9]; + sprintf(errorString, "%08x", uint32_t(aRv)); + result->CompleteExceptionally( + mozilla::java::sdk::IllegalStateException::New(errorString) + .Cast<jni::Throwable>()); + + // Failed to capture a profile. Stop the profiler. + profiler_stop(); + }); + } +}; +#endif + +constexpr static bool ValidateFeatures() { + int expectedFeatureNumber = 0; + + // Feature numbers should start at 0 and increase by 1 each. +#define CHECK_FEATURE(n_, str_, Name_, desc_) \ + if ((n_) != expectedFeatureNumber) { \ + return false; \ + } \ + ++expectedFeatureNumber; + + PROFILER_FOR_EACH_FEATURE(CHECK_FEATURE) + +#undef CHECK_FEATURE + + return true; +} + +static_assert(ValidateFeatures(), "Feature list is invalid"); + +// Return all features that are available on this platform. +static uint32_t AvailableFeatures() { + uint32_t features = 0; + +#define ADD_FEATURE(n_, str_, Name_, desc_) \ + ProfilerFeature::Set##Name_(features); + + // Add all the possible features. + PROFILER_FOR_EACH_FEATURE(ADD_FEATURE) + +#undef ADD_FEATURE + + // Now remove features not supported on this platform/configuration. +#if !defined(GP_OS_android) + ProfilerFeature::ClearJava(features); +#endif +#if !defined(HAVE_NATIVE_UNWIND) + ProfilerFeature::ClearStackWalk(features); +#endif +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + if (getenv("XPCOM_MEM_BLOAT_LOG")) { + DEBUG_LOG("XPCOM_MEM_BLOAT_LOG is set, disabling native allocations."); + // The memory hooks are available, but the bloat log is enabled, which is + // not compatible with the native allocations tracking. See the comment in + // enable_native_allocations() (tools/profiler/core/memory_hooks.cpp) for + // more information. + ProfilerFeature::ClearNativeAllocations(features); + } +#else + // The memory hooks are not available. + ProfilerFeature::ClearNativeAllocations(features); +#endif + +#if !defined(GP_OS_windows) + ProfilerFeature::ClearNoTimerResolutionChange(features); +#endif +#if !defined(HAVE_CPU_FREQ_SUPPORT) + ProfilerFeature::ClearCPUFrequency(features); +#endif + + return features; +} + +// Default features common to all contexts (even if not available). +static constexpr uint32_t DefaultFeatures() { + return ProfilerFeature::Java | ProfilerFeature::JS | + ProfilerFeature::StackWalk | ProfilerFeature::CPUUtilization | + ProfilerFeature::Screenshots | ProfilerFeature::ProcessCPU; +} + +// Extra default features when MOZ_PROFILER_STARTUP is set (even if not +// available). +static constexpr uint32_t StartupExtraDefaultFeatures() { + // Enable file I/Os by default for startup profiles as startup is heavy on + // I/O operations. + return ProfilerFeature::FileIOAll | ProfilerFeature::IPCMessages; +} + +Json::String ToCompactString(const Json::Value& aJsonValue) { + Json::StreamWriterBuilder builder; + // No indentations, and no newlines. + builder["indentation"] = ""; + // This removes spaces after colons. + builder["enableYAMLCompatibility"] = false; + // Only 6 digits after the decimal point; timestamps in ms have ns precision. + builder["precision"] = 6; + builder["precisionType"] = "decimal"; + + return Json::writeString(builder, aJsonValue); +} + +/* static */ mozilla::baseprofiler::detail::BaseProfilerMutex + ProfilingLog::gMutex; +/* static */ mozilla::UniquePtr<Json::Value> ProfilingLog::gLog; + +/* static */ void ProfilingLog::Init() { + mozilla::baseprofiler::detail::BaseProfilerAutoLock lock{gMutex}; + MOZ_ASSERT(!gLog); + gLog = mozilla::MakeUniqueFallible<Json::Value>(Json::objectValue); + if (gLog) { + (*gLog)[Json::StaticString{"profilingLogBegin" TIMESTAMP_JSON_SUFFIX}] = + ProfilingLog::Timestamp(); + } +} + +/* static */ void ProfilingLog::Destroy() { + mozilla::baseprofiler::detail::BaseProfilerAutoLock lock{gMutex}; + MOZ_ASSERT(gLog); + gLog = nullptr; +} + +/* static */ bool ProfilingLog::IsLockedOnCurrentThread() { + return gMutex.IsLockedOnCurrentThread(); +} + +// RAII class to lock the profiler mutex. +// It provides a mechanism to determine if it is locked or not in order for +// memory hooks to avoid re-entering the profiler locked state. +// Locking order: Profiler, ThreadRegistry, ThreadRegistration. +class MOZ_RAII PSAutoLock { + public: + PSAutoLock() + : mLock([]() -> mozilla::baseprofiler::detail::BaseProfilerMutex& { + // In DEBUG builds, *before* we attempt to lock gPSMutex, we want to + // check that the ThreadRegistry, ThreadRegistration, and ProfilingLog + // mutexes are *not* locked on this thread, to avoid inversion + // deadlocks. + MOZ_ASSERT(!ThreadRegistry::IsRegistryMutexLockedOnCurrentThread()); + MOZ_ASSERT(!ThreadRegistration::IsDataMutexLockedOnCurrentThread()); + MOZ_ASSERT(!ProfilingLog::IsLockedOnCurrentThread()); + return gPSMutex; + }()) {} + + PSAutoLock(const PSAutoLock&) = delete; + void operator=(const PSAutoLock&) = delete; + + static bool IsLockedOnCurrentThread() { + return gPSMutex.IsLockedOnCurrentThread(); + } + + private: + static mozilla::baseprofiler::detail::BaseProfilerMutex gPSMutex; + mozilla::baseprofiler::detail::BaseProfilerAutoLock mLock; +}; + +/* static */ mozilla::baseprofiler::detail::BaseProfilerMutex + PSAutoLock::gPSMutex{"Gecko Profiler mutex"}; + +// Only functions that take a PSLockRef arg can access CorePS's and ActivePS's +// fields. +typedef const PSAutoLock& PSLockRef; + +#define PS_GET(type_, name_) \ + static type_ name_(PSLockRef) { \ + MOZ_ASSERT(sInstance); \ + return sInstance->m##name_; \ + } + +#define PS_GET_LOCKLESS(type_, name_) \ + static type_ name_() { \ + MOZ_ASSERT(sInstance); \ + return sInstance->m##name_; \ + } + +#define PS_GET_AND_SET(type_, name_) \ + PS_GET(type_, name_) \ + static void Set##name_(PSLockRef, type_ a##name_) { \ + MOZ_ASSERT(sInstance); \ + sInstance->m##name_ = a##name_; \ + } + +static constexpr size_t MAX_JS_FRAMES = + mozilla::profiler::ThreadRegistrationData::MAX_JS_FRAMES; +using JsFrame = mozilla::profiler::ThreadRegistrationData::JsFrame; +using JsFrameBuffer = mozilla::profiler::ThreadRegistrationData::JsFrameBuffer; + +// All functions in this file can run on multiple threads unless they have an +// NS_IsMainThread() assertion. + +// This class contains the profiler's core global state, i.e. that which is +// valid even when the profiler is not active. Most profile operations can't do +// anything useful when this class is not instantiated, so we release-assert +// its non-nullness in all such operations. +// +// Accesses to CorePS are guarded by gPSMutex. Getters and setters take a +// PSAutoLock reference as an argument as proof that the gPSMutex is currently +// locked. This makes it clear when gPSMutex is locked and helps avoid +// accidental unlocked accesses to global state. There are ways to circumvent +// this mechanism, but please don't do so without *very* good reason and a +// detailed explanation. +// +// The exceptions to this rule: +// +// - mProcessStartTime, because it's immutable; +class CorePS { + private: + CorePS() + : mProcessStartTime(TimeStamp::ProcessCreation()), + mMaybeBandwidthCounter(nullptr) +#ifdef USE_LUL_STACKWALK + , + mLul(nullptr) +#endif + { + MOZ_ASSERT(NS_IsMainThread(), + "CorePS must be created from the main thread"); + } + + ~CorePS() { +#ifdef USE_LUL_STACKWALK + delete sInstance->mLul; + delete mMaybeBandwidthCounter; +#endif + } + + public: + static void Create(PSLockRef aLock) { + MOZ_ASSERT(!sInstance); + sInstance = new CorePS(); + } + + static void Destroy(PSLockRef aLock) { + MOZ_ASSERT(sInstance); + delete sInstance; + sInstance = nullptr; + } + + // Unlike ActivePS::Exists(), CorePS::Exists() can be called without gPSMutex + // being locked. This is because CorePS is instantiated so early on the main + // thread that we don't have to worry about it being racy. + static bool Exists() { return !!sInstance; } + + static void AddSizeOf(PSLockRef, MallocSizeOf aMallocSizeOf, + size_t& aProfSize, size_t& aLulSize) { + MOZ_ASSERT(sInstance); + + aProfSize += aMallocSizeOf(sInstance); + + aProfSize += ThreadRegistry::SizeOfIncludingThis(aMallocSizeOf); + + for (auto& registeredPage : sInstance->mRegisteredPages) { + aProfSize += registeredPage->SizeOfIncludingThis(aMallocSizeOf); + } + + // Measurement of the following things may be added later if DMD finds it + // is worthwhile: + // - CorePS::mRegisteredPages itself (its elements' children are + // measured above) + +#if defined(USE_LUL_STACKWALK) + if (lul::LUL* lulPtr = sInstance->mLul; lulPtr) { + aLulSize += lulPtr->SizeOfIncludingThis(aMallocSizeOf); + } +#endif + } + + // No PSLockRef is needed for this field because it's immutable. + PS_GET_LOCKLESS(TimeStamp, ProcessStartTime) + + PS_GET(JsFrameBuffer&, JsFrames) + + PS_GET(Vector<RefPtr<PageInformation>>&, RegisteredPages) + + static void AppendRegisteredPage(PSLockRef, + RefPtr<PageInformation>&& aRegisteredPage) { + MOZ_ASSERT(sInstance); + struct RegisteredPageComparator { + PageInformation* aA; + bool operator()(PageInformation* aB) const { return aA->Equals(aB); } + }; + + auto foundPageIter = std::find_if( + sInstance->mRegisteredPages.begin(), sInstance->mRegisteredPages.end(), + RegisteredPageComparator{aRegisteredPage.get()}); + + if (foundPageIter != sInstance->mRegisteredPages.end()) { + if ((*foundPageIter)->Url().EqualsLiteral("about:blank")) { + // When a BrowsingContext is loaded, the first url loaded in it will be + // about:blank, and if the principal matches, the first document loaded + // in it will share an inner window. That's why we should delete the + // intermittent about:blank if they share the inner window. + sInstance->mRegisteredPages.erase(foundPageIter); + } else { + // Do not register the same page again. + return; + } + } + + MOZ_RELEASE_ASSERT( + sInstance->mRegisteredPages.append(std::move(aRegisteredPage))); + } + + static void RemoveRegisteredPage(PSLockRef, + uint64_t aRegisteredInnerWindowID) { + MOZ_ASSERT(sInstance); + // Remove RegisteredPage from mRegisteredPages by given inner window ID. + sInstance->mRegisteredPages.eraseIf([&](const RefPtr<PageInformation>& rd) { + return rd->InnerWindowID() == aRegisteredInnerWindowID; + }); + } + + static void ClearRegisteredPages(PSLockRef) { + MOZ_ASSERT(sInstance); + sInstance->mRegisteredPages.clear(); + } + + PS_GET(const Vector<BaseProfilerCount*>&, Counters) + + static void AppendCounter(PSLockRef, BaseProfilerCount* aCounter) { + MOZ_ASSERT(sInstance); + // we don't own the counter; they may be stored in static objects + MOZ_RELEASE_ASSERT(sInstance->mCounters.append(aCounter)); + } + + static void RemoveCounter(PSLockRef, BaseProfilerCount* aCounter) { + // we may be called to remove a counter after the profiler is stopped or + // late in shutdown. + if (sInstance) { + auto* counter = std::find(sInstance->mCounters.begin(), + sInstance->mCounters.end(), aCounter); + MOZ_RELEASE_ASSERT(counter != sInstance->mCounters.end()); + sInstance->mCounters.erase(counter); + } + } + +#ifdef USE_LUL_STACKWALK + static lul::LUL* Lul() { + MOZ_RELEASE_ASSERT(sInstance); + return sInstance->mLul; + } + static void SetLul(UniquePtr<lul::LUL> aLul) { + MOZ_RELEASE_ASSERT(sInstance); + MOZ_RELEASE_ASSERT( + sInstance->mLul.compareExchange(nullptr, aLul.release())); + } +#endif + + PS_GET_AND_SET(const nsACString&, ProcessName) + PS_GET_AND_SET(const nsACString&, ETLDplus1) + + static void SetBandwidthCounter(ProfilerBandwidthCounter* aBandwidthCounter) { + MOZ_ASSERT(sInstance); + + sInstance->mMaybeBandwidthCounter = aBandwidthCounter; + } + static ProfilerBandwidthCounter* GetBandwidthCounter() { + MOZ_ASSERT(sInstance); + + return sInstance->mMaybeBandwidthCounter; + } + + private: + // The singleton instance + static CorePS* sInstance; + + // The time that the process started. + const TimeStamp mProcessStartTime; + + // Network bandwidth counter for the Bandwidth feature. + ProfilerBandwidthCounter* mMaybeBandwidthCounter; + + // Info on all the registered pages. + // InnerWindowIDs in mRegisteredPages are unique. + Vector<RefPtr<PageInformation>> mRegisteredPages; + + // Non-owning pointers to all active counters + Vector<BaseProfilerCount*> mCounters; + +#ifdef USE_LUL_STACKWALK + // LUL's state. Null prior to the first activation, non-null thereafter. + // Owned by this CorePS. + mozilla::Atomic<lul::LUL*> mLul; +#endif + + // Process name, provided by child process initialization code. + nsAutoCString mProcessName; + // Private name, provided by child process initialization code (eTLD+1 in + // fission) + nsAutoCString mETLDplus1; + + // This memory buffer is used by the MergeStacks mechanism. Previously it was + // stack allocated, but this led to a stack overflow, as it was too much + // memory. Here the buffer can be pre-allocated, and shared with the + // MergeStacks feature as needed. MergeStacks is only run while holding the + // lock, so it is safe to have only one instance allocated for all of the + // threads. + JsFrameBuffer mJsFrames; +}; + +CorePS* CorePS::sInstance = nullptr; + +void locked_profiler_add_sampled_counter(PSLockRef aLock, + BaseProfilerCount* aCounter) { + CorePS::AppendCounter(aLock, aCounter); +} + +void locked_profiler_remove_sampled_counter(PSLockRef aLock, + BaseProfilerCount* aCounter) { + // Note: we don't enforce a final sample, though we could do so if the + // profiler was active + CorePS::RemoveCounter(aLock, aCounter); +} + +class SamplerThread; + +static SamplerThread* NewSamplerThread(PSLockRef aLock, uint32_t aGeneration, + double aInterval, uint32_t aFeatures); + +struct LiveProfiledThreadData { + UniquePtr<ProfiledThreadData> mProfiledThreadData; +}; + +// This class contains the profiler's global state that is valid only when the +// profiler is active. When not instantiated, the profiler is inactive. +// +// Accesses to ActivePS are guarded by gPSMutex, in much the same fashion as +// CorePS. +// +class ActivePS { + private: + constexpr static uint32_t ChunkSizeForEntries(uint32_t aEntries) { + return uint32_t(std::min(size_t(ClampToAllowedEntries(aEntries)) * + scBytesPerEntry / scMinimumNumberOfChunks, + size_t(scMaximumChunkSize))); + } + + static uint32_t AdjustFeatures(uint32_t aFeatures, uint32_t aFilterCount) { + // Filter out any features unavailable in this platform/configuration. + aFeatures &= AvailableFeatures(); + + // Some features imply others. + if (aFeatures & ProfilerFeature::FileIOAll) { + aFeatures |= ProfilerFeature::MainThreadIO | ProfilerFeature::FileIO; + } else if (aFeatures & ProfilerFeature::FileIO) { + aFeatures |= ProfilerFeature::MainThreadIO; + } + + if (aFeatures & ProfilerFeature::CPUAllThreads) { + aFeatures |= ProfilerFeature::CPUUtilization; + } + + return aFeatures; + } + + bool ShouldInterposeIOs() { + return ProfilerFeature::HasMainThreadIO(mFeatures) || + ProfilerFeature::HasFileIO(mFeatures) || + ProfilerFeature::HasFileIOAll(mFeatures); + } + + ActivePS( + PSLockRef aLock, const TimeStamp& aProfilingStartTime, + PowerOfTwo32 aCapacity, double aInterval, uint32_t aFeatures, + const char** aFilters, uint32_t aFilterCount, uint64_t aActiveTabID, + const Maybe<double>& aDuration, + UniquePtr<ProfileBufferChunkManagerWithLocalLimit> aChunkManagerOrNull) + : mProfilingStartTime(aProfilingStartTime), + mGeneration(sNextGeneration++), + mCapacity(aCapacity), + mDuration(aDuration), + mInterval(aInterval), + mFeatures(AdjustFeatures(aFeatures, aFilterCount)), + mActiveTabID(aActiveTabID), + mProfileBufferChunkManager( + aChunkManagerOrNull + ? std::move(aChunkManagerOrNull) + : MakeUnique<ProfileBufferChunkManagerWithLocalLimit>( + size_t(ClampToAllowedEntries(aCapacity.Value())) * + scBytesPerEntry, + ChunkSizeForEntries(aCapacity.Value()))), + mProfileBuffer([this]() -> ProfileChunkedBuffer& { + ProfileChunkedBuffer& coreBuffer = profiler_get_core_buffer(); + coreBuffer.SetChunkManagerIfDifferent(*mProfileBufferChunkManager); + return coreBuffer; + }()), + mMaybeProcessCPUCounter(ProfilerFeature::HasProcessCPU(aFeatures) + ? new ProcessCPUCounter(aLock) + : nullptr), + mMaybePowerCounters(nullptr), + mMaybeCPUFreq(nullptr), + // The new sampler thread doesn't start sampling immediately because the + // main loop within Run() is blocked until this function's caller + // unlocks gPSMutex. + mSamplerThread( + NewSamplerThread(aLock, mGeneration, aInterval, aFeatures)), + mIsPaused(false), + mIsSamplingPaused(false) { + ProfilingLog::Init(); + + // Deep copy and lower-case aFilters. + MOZ_ALWAYS_TRUE(mFilters.resize(aFilterCount)); + MOZ_ALWAYS_TRUE(mFiltersLowered.resize(aFilterCount)); + for (uint32_t i = 0; i < aFilterCount; ++i) { + mFilters[i] = aFilters[i]; + mFiltersLowered[i].reserve(mFilters[i].size()); + std::transform(mFilters[i].cbegin(), mFilters[i].cend(), + std::back_inserter(mFiltersLowered[i]), ::tolower); + } + +#if !defined(RELEASE_OR_BETA) + if (ShouldInterposeIOs()) { + // We need to register the observer on the main thread, because we want + // to observe IO that happens on the main thread. + // IOInterposer needs to be initialized before calling + // IOInterposer::Register or our observer will be silently dropped. + if (NS_IsMainThread()) { + IOInterposer::Init(); + IOInterposer::Register(IOInterposeObserver::OpAll, + &ProfilerIOInterposeObserver::GetInstance()); + } else { + NS_DispatchToMainThread( + NS_NewRunnableFunction("ActivePS::ActivePS", []() { + // Note: This could theoretically happen after ActivePS gets + // destroyed, but it's ok: + // - The Observer always checks that the profiler is (still) + // active before doing its work. + // - The destruction should happen on the same thread as this + // construction, so the un-registration will also be dispatched + // and queued on the main thread, and run after this. + IOInterposer::Init(); + IOInterposer::Register( + IOInterposeObserver::OpAll, + &ProfilerIOInterposeObserver::GetInstance()); + })); + } + } +#endif + + if (ProfilerFeature::HasPower(aFeatures)) { + mMaybePowerCounters = new PowerCounters(); + for (const auto& powerCounter : mMaybePowerCounters->GetCounters()) { + locked_profiler_add_sampled_counter(aLock, powerCounter); + } + } + + if (ProfilerFeature::HasCPUFrequency(aFeatures)) { + mMaybeCPUFreq = new ProfilerCPUFreq(); + } + } + + ~ActivePS() { + MOZ_ASSERT( + !mMaybeProcessCPUCounter, + "mMaybeProcessCPUCounter should have been deleted before ~ActivePS()"); + MOZ_ASSERT( + !mMaybePowerCounters, + "mMaybePowerCounters should have been deleted before ~ActivePS()"); + MOZ_ASSERT(!mMaybeCPUFreq, + "mMaybeCPUFreq should have been deleted before ~ActivePS()"); + +#if !defined(RELEASE_OR_BETA) + if (ShouldInterposeIOs()) { + // We need to unregister the observer on the main thread, because that's + // where we've registered it. + if (NS_IsMainThread()) { + IOInterposer::Unregister(IOInterposeObserver::OpAll, + &ProfilerIOInterposeObserver::GetInstance()); + } else { + NS_DispatchToMainThread( + NS_NewRunnableFunction("ActivePS::~ActivePS", []() { + IOInterposer::Unregister( + IOInterposeObserver::OpAll, + &ProfilerIOInterposeObserver::GetInstance()); + })); + } + } +#endif + if (mProfileBufferChunkManager) { + // We still control the chunk manager, remove it from the core buffer. + profiler_get_core_buffer().ResetChunkManager(); + } + + ProfilingLog::Destroy(); + } + + bool ThreadSelected(const char* aThreadName) { + if (mFiltersLowered.empty()) { + return true; + } + + std::string name = aThreadName; + std::transform(name.begin(), name.end(), name.begin(), ::tolower); + + for (const auto& filter : mFiltersLowered) { + if (filter == "*") { + return true; + } + + // Crude, non UTF-8 compatible, case insensitive substring search + if (name.find(filter) != std::string::npos) { + return true; + } + + // If the filter is "pid:<my pid>", profile all threads. + if (mozilla::profiler::detail::FilterHasPid(filter.c_str())) { + return true; + } + } + + return false; + } + + public: + static void Create( + PSLockRef aLock, const TimeStamp& aProfilingStartTime, + PowerOfTwo32 aCapacity, double aInterval, uint32_t aFeatures, + const char** aFilters, uint32_t aFilterCount, uint64_t aActiveTabID, + const Maybe<double>& aDuration, + UniquePtr<ProfileBufferChunkManagerWithLocalLimit> aChunkManagerOrNull) { + MOZ_ASSERT(!sInstance); + sInstance = new ActivePS(aLock, aProfilingStartTime, aCapacity, aInterval, + aFeatures, aFilters, aFilterCount, aActiveTabID, + aDuration, std::move(aChunkManagerOrNull)); + } + + [[nodiscard]] static SamplerThread* Destroy(PSLockRef aLock) { + MOZ_ASSERT(sInstance); + if (sInstance->mMaybeProcessCPUCounter) { + locked_profiler_remove_sampled_counter( + aLock, sInstance->mMaybeProcessCPUCounter); + delete sInstance->mMaybeProcessCPUCounter; + sInstance->mMaybeProcessCPUCounter = nullptr; + } + + if (sInstance->mMaybePowerCounters) { + for (const auto& powerCounter : + sInstance->mMaybePowerCounters->GetCounters()) { + locked_profiler_remove_sampled_counter(aLock, powerCounter); + } + delete sInstance->mMaybePowerCounters; + sInstance->mMaybePowerCounters = nullptr; + } + + if (sInstance->mMaybeCPUFreq) { + delete sInstance->mMaybeCPUFreq; + sInstance->mMaybeCPUFreq = nullptr; + } + + ProfilerBandwidthCounter* counter = CorePS::GetBandwidthCounter(); + if (counter && counter->IsRegistered()) { + // Because profiler_count_bandwidth_bytes does a racy + // profiler_feature_active check to avoid taking the lock, + // free'ing the memory of the counter would be crashy if the + // socket thread attempts to increment the counter while we are + // stopping the profiler. + // Instead, we keep the counter in CorePS and only mark it as + // unregistered so that the next attempt to count bytes + // will re-register it. + locked_profiler_remove_sampled_counter(aLock, counter); + counter->MarkUnregistered(); + } + + auto samplerThread = sInstance->mSamplerThread; + delete sInstance; + sInstance = nullptr; + + return samplerThread; + } + + static bool Exists(PSLockRef) { return !!sInstance; } + + static bool Equals(PSLockRef, PowerOfTwo32 aCapacity, + const Maybe<double>& aDuration, double aInterval, + uint32_t aFeatures, const char** aFilters, + uint32_t aFilterCount, uint64_t aActiveTabID) { + MOZ_ASSERT(sInstance); + if (sInstance->mCapacity != aCapacity || + sInstance->mDuration != aDuration || + sInstance->mInterval != aInterval || + sInstance->mFeatures != aFeatures || + sInstance->mFilters.length() != aFilterCount || + sInstance->mActiveTabID != aActiveTabID) { + return false; + } + + for (uint32_t i = 0; i < sInstance->mFilters.length(); ++i) { + if (strcmp(sInstance->mFilters[i].c_str(), aFilters[i]) != 0) { + return false; + } + } + return true; + } + + static size_t SizeOf(PSLockRef, MallocSizeOf aMallocSizeOf) { + MOZ_ASSERT(sInstance); + + size_t n = aMallocSizeOf(sInstance); + + n += sInstance->mProfileBuffer.SizeOfExcludingThis(aMallocSizeOf); + + // Measurement of the following members may be added later if DMD finds it + // is worthwhile: + // - mLiveProfiledThreads (both the array itself, and the contents) + // - mDeadProfiledThreads (both the array itself, and the contents) + // + + return n; + } + + static ThreadProfilingFeatures ProfilingFeaturesForThread( + PSLockRef aLock, const ThreadRegistrationInfo& aInfo) { + MOZ_ASSERT(sInstance); + if (sInstance->ThreadSelected(aInfo.Name())) { + // This thread was selected by the user, record everything. + return ThreadProfilingFeatures::Any; + } + ThreadProfilingFeatures features = ThreadProfilingFeatures::NotProfiled; + if (ActivePS::FeatureCPUAllThreads(aLock)) { + features = Combine(features, ThreadProfilingFeatures::CPUUtilization); + } + if (ActivePS::FeatureSamplingAllThreads(aLock)) { + features = Combine(features, ThreadProfilingFeatures::Sampling); + } + if (ActivePS::FeatureMarkersAllThreads(aLock)) { + features = Combine(features, ThreadProfilingFeatures::Markers); + } + return features; + } + + [[nodiscard]] static bool AppendPostSamplingCallback( + PSLockRef, PostSamplingCallback&& aCallback); + + // Writes out the current active configuration of the profile. + static void WriteActiveConfiguration( + PSLockRef aLock, JSONWriter& aWriter, + const Span<const char>& aPropertyName = MakeStringSpan("")) { + if (!sInstance) { + if (!aPropertyName.empty()) { + aWriter.NullProperty(aPropertyName); + } else { + aWriter.NullElement(); + } + return; + }; + + if (!aPropertyName.empty()) { + aWriter.StartObjectProperty(aPropertyName); + } else { + aWriter.StartObjectElement(); + } + + { + aWriter.StartArrayProperty("features"); +#define WRITE_ACTIVE_FEATURES(n_, str_, Name_, desc_) \ + if (profiler_feature_active(ProfilerFeature::Name_)) { \ + aWriter.StringElement(str_); \ + } + + PROFILER_FOR_EACH_FEATURE(WRITE_ACTIVE_FEATURES) +#undef WRITE_ACTIVE_FEATURES + aWriter.EndArray(); + } + { + aWriter.StartArrayProperty("threads"); + for (const auto& filter : sInstance->mFilters) { + aWriter.StringElement(filter); + } + aWriter.EndArray(); + } + { + // Now write all the simple values. + + // The interval is also available on profile.meta.interval + aWriter.DoubleProperty("interval", sInstance->mInterval); + aWriter.IntProperty("capacity", sInstance->mCapacity.Value()); + if (sInstance->mDuration) { + aWriter.DoubleProperty("duration", sInstance->mDuration.value()); + } + // Here, we are converting uint64_t to double. Tab IDs are + // being created using `nsContentUtils::GenerateProcessSpecificId`, which + // is specifically designed to only use 53 of the 64 bits to be lossless + // when passed into and out of JS as a double. + aWriter.DoubleProperty("activeTabID", sInstance->mActiveTabID); + } + aWriter.EndObject(); + } + + PS_GET_LOCKLESS(TimeStamp, ProfilingStartTime) + + PS_GET(uint32_t, Generation) + + PS_GET(PowerOfTwo32, Capacity) + + PS_GET(Maybe<double>, Duration) + + PS_GET(double, Interval) + + PS_GET(uint32_t, Features) + + PS_GET(uint64_t, ActiveTabID) + +#define PS_GET_FEATURE(n_, str_, Name_, desc_) \ + static bool Feature##Name_(PSLockRef) { \ + MOZ_ASSERT(sInstance); \ + return ProfilerFeature::Has##Name_(sInstance->mFeatures); \ + } + + PROFILER_FOR_EACH_FEATURE(PS_GET_FEATURE) + +#undef PS_GET_FEATURE + + static uint32_t JSFlags(PSLockRef aLock) { + uint32_t Flags = 0; + Flags |= + FeatureJS(aLock) ? uint32_t(JSInstrumentationFlags::StackSampling) : 0; + + Flags |= FeatureJSAllocations(aLock) + ? uint32_t(JSInstrumentationFlags::Allocations) + : 0; + return Flags; + } + + PS_GET(const Vector<std::string>&, Filters) + PS_GET(const Vector<std::string>&, FiltersLowered) + + // Not using PS_GET, because only the "Controlled" interface of + // `mProfileBufferChunkManager` should be exposed here. + static ProfileBufferChunkManagerWithLocalLimit& ControlledChunkManager( + PSLockRef) { + MOZ_ASSERT(sInstance); + MOZ_ASSERT(sInstance->mProfileBufferChunkManager); + return *sInstance->mProfileBufferChunkManager; + } + + static void FulfillChunkRequests(PSLockRef) { + MOZ_ASSERT(sInstance); + if (sInstance->mProfileBufferChunkManager) { + sInstance->mProfileBufferChunkManager->FulfillChunkRequests(); + } + } + + static ProfileBuffer& Buffer(PSLockRef) { + MOZ_ASSERT(sInstance); + return sInstance->mProfileBuffer; + } + + static const Vector<LiveProfiledThreadData>& LiveProfiledThreads(PSLockRef) { + MOZ_ASSERT(sInstance); + return sInstance->mLiveProfiledThreads; + } + + struct ProfiledThreadListElement { + TimeStamp mRegisterTime; + JSContext* mJSContext; // Null for unregistered threads. + ProfiledThreadData* mProfiledThreadData; + }; + using ProfiledThreadList = Vector<ProfiledThreadListElement>; + + // Returns a ProfiledThreadList with all threads that should be included in a + // profile, both for threads that are still registered, and for threads that + // have been unregistered but still have data in the buffer. + // The returned array is sorted by thread register time. + // Do not hold on to the return value past LockedRegistry. + static ProfiledThreadList ProfiledThreads( + ThreadRegistry::LockedRegistry& aLockedRegistry, PSLockRef aLock) { + MOZ_ASSERT(sInstance); + ProfiledThreadList array; + MOZ_RELEASE_ASSERT( + array.initCapacity(sInstance->mLiveProfiledThreads.length() + + sInstance->mDeadProfiledThreads.length())); + + for (ThreadRegistry::OffThreadRef offThreadRef : aLockedRegistry) { + ProfiledThreadData* profiledThreadData = + offThreadRef.UnlockedRWForLockedProfilerRef().GetProfiledThreadData( + aLock); + if (!profiledThreadData) { + // This thread was not profiled, continue with the next one. + continue; + } + ThreadRegistry::OffThreadRef::RWFromAnyThreadWithLock lockedThreadData = + offThreadRef.GetLockedRWFromAnyThread(); + MOZ_RELEASE_ASSERT(array.append(ProfiledThreadListElement{ + profiledThreadData->Info().RegisterTime(), + lockedThreadData->GetJSContext(), profiledThreadData})); + } + + for (auto& t : sInstance->mDeadProfiledThreads) { + MOZ_RELEASE_ASSERT(array.append(ProfiledThreadListElement{ + t->Info().RegisterTime(), (JSContext*)nullptr, t.get()})); + } + + std::sort(array.begin(), array.end(), + [](const ProfiledThreadListElement& a, + const ProfiledThreadListElement& b) { + return a.mRegisterTime < b.mRegisterTime; + }); + return array; + } + + static Vector<RefPtr<PageInformation>> ProfiledPages(PSLockRef aLock) { + MOZ_ASSERT(sInstance); + Vector<RefPtr<PageInformation>> array; + for (auto& d : CorePS::RegisteredPages(aLock)) { + MOZ_RELEASE_ASSERT(array.append(d)); + } + for (auto& d : sInstance->mDeadProfiledPages) { + MOZ_RELEASE_ASSERT(array.append(d)); + } + // We don't need to sort the pages like threads since we won't show them + // as a list. + return array; + } + + static ProfiledThreadData* AddLiveProfiledThread( + PSLockRef, UniquePtr<ProfiledThreadData>&& aProfiledThreadData) { + MOZ_ASSERT(sInstance); + MOZ_RELEASE_ASSERT(sInstance->mLiveProfiledThreads.append( + LiveProfiledThreadData{std::move(aProfiledThreadData)})); + + // Return a weak pointer to the ProfiledThreadData object. + return sInstance->mLiveProfiledThreads.back().mProfiledThreadData.get(); + } + + static void UnregisterThread(PSLockRef aLockRef, + ProfiledThreadData* aProfiledThreadData) { + MOZ_ASSERT(sInstance); + + DiscardExpiredDeadProfiledThreads(aLockRef); + + // Find the right entry in the mLiveProfiledThreads array and remove the + // element, moving the ProfiledThreadData object for the thread into the + // mDeadProfiledThreads array. + for (size_t i = 0; i < sInstance->mLiveProfiledThreads.length(); i++) { + LiveProfiledThreadData& thread = sInstance->mLiveProfiledThreads[i]; + if (thread.mProfiledThreadData == aProfiledThreadData) { + thread.mProfiledThreadData->NotifyUnregistered( + sInstance->mProfileBuffer.BufferRangeEnd()); + MOZ_RELEASE_ASSERT(sInstance->mDeadProfiledThreads.append( + std::move(thread.mProfiledThreadData))); + sInstance->mLiveProfiledThreads.erase( + &sInstance->mLiveProfiledThreads[i]); + return; + } + } + } + + // This is a counter to collect process CPU utilization during profiling. + // It cannot be a raw `ProfilerCounter` because we need to manually add/remove + // it while the profiler lock is already held. + class ProcessCPUCounter final : public BaseProfilerCount { + public: + explicit ProcessCPUCounter(PSLockRef aLock) + : BaseProfilerCount("processCPU", &mCounter, nullptr, "CPU", + "Process CPU utilization") { + // Adding on construction, so it's ready before the sampler starts. + locked_profiler_add_sampled_counter(aLock, this); + // Note: Removed from ActivePS::Destroy, because a lock is needed. + } + + void Add(int64_t aNumber) { mCounter += aNumber; } + + private: + ProfilerAtomicSigned mCounter; + }; + PS_GET(ProcessCPUCounter*, MaybeProcessCPUCounter); + + PS_GET(PowerCounters*, MaybePowerCounters); + + PS_GET(ProfilerCPUFreq*, MaybeCPUFreq); + + PS_GET_AND_SET(bool, IsPaused) + + // True if sampling is paused (though generic `SetIsPaused()` or specific + // `SetIsSamplingPaused()`). + static bool IsSamplingPaused(PSLockRef lock) { + MOZ_ASSERT(sInstance); + return IsPaused(lock) || sInstance->mIsSamplingPaused; + } + + static void SetIsSamplingPaused(PSLockRef, bool aIsSamplingPaused) { + MOZ_ASSERT(sInstance); + sInstance->mIsSamplingPaused = aIsSamplingPaused; + } + + static void DiscardExpiredDeadProfiledThreads(PSLockRef) { + MOZ_ASSERT(sInstance); + uint64_t bufferRangeStart = sInstance->mProfileBuffer.BufferRangeStart(); + // Discard any dead threads that were unregistered before bufferRangeStart. + sInstance->mDeadProfiledThreads.eraseIf( + [bufferRangeStart]( + const UniquePtr<ProfiledThreadData>& aProfiledThreadData) { + Maybe<uint64_t> bufferPosition = + aProfiledThreadData->BufferPositionWhenUnregistered(); + MOZ_RELEASE_ASSERT(bufferPosition, + "should have unregistered this thread"); + return *bufferPosition < bufferRangeStart; + }); + } + + static void UnregisterPage(PSLockRef aLock, + uint64_t aRegisteredInnerWindowID) { + MOZ_ASSERT(sInstance); + auto& registeredPages = CorePS::RegisteredPages(aLock); + for (size_t i = 0; i < registeredPages.length(); i++) { + RefPtr<PageInformation>& page = registeredPages[i]; + if (page->InnerWindowID() == aRegisteredInnerWindowID) { + page->NotifyUnregistered(sInstance->mProfileBuffer.BufferRangeEnd()); + MOZ_RELEASE_ASSERT( + sInstance->mDeadProfiledPages.append(std::move(page))); + registeredPages.erase(®isteredPages[i--]); + } + } + } + + static void DiscardExpiredPages(PSLockRef) { + MOZ_ASSERT(sInstance); + uint64_t bufferRangeStart = sInstance->mProfileBuffer.BufferRangeStart(); + // Discard any dead pages that were unregistered before + // bufferRangeStart. + sInstance->mDeadProfiledPages.eraseIf( + [bufferRangeStart](const RefPtr<PageInformation>& aProfiledPage) { + Maybe<uint64_t> bufferPosition = + aProfiledPage->BufferPositionWhenUnregistered(); + MOZ_RELEASE_ASSERT(bufferPosition, + "should have unregistered this page"); + return *bufferPosition < bufferRangeStart; + }); + } + + static void ClearUnregisteredPages(PSLockRef) { + MOZ_ASSERT(sInstance); + sInstance->mDeadProfiledPages.clear(); + } + + static void ClearExpiredExitProfiles(PSLockRef) { + MOZ_ASSERT(sInstance); + uint64_t bufferRangeStart = sInstance->mProfileBuffer.BufferRangeStart(); + // Discard exit profiles that were gathered before our buffer RangeStart. + // If we have started to overwrite our data from when the Base profile was + // added, we should get rid of that Base profile because it's now older than + // our oldest Gecko profile data. + // + // When adding: (In practice the starting buffer should be empty) + // v Start == End + // | <-- Buffer range, initially empty. + // ^ mGeckoIndexWhenBaseProfileAdded < Start FALSE -> keep it + // + // Later, still in range: + // v Start v End + // |=========| <-- Buffer range growing. + // ^ mGeckoIndexWhenBaseProfileAdded < Start FALSE -> keep it + // + // Even later, now out of range: + // v Start v End + // |============| <-- Buffer range full and sliding. + // ^ mGeckoIndexWhenBaseProfileAdded < Start TRUE! -> Discard it + if (sInstance->mBaseProfileThreads && + sInstance->mGeckoIndexWhenBaseProfileAdded + .ConvertToProfileBufferIndex() < + profiler_get_core_buffer().GetState().mRangeStart) { + DEBUG_LOG("ClearExpiredExitProfiles() - Discarding base profile %p", + sInstance->mBaseProfileThreads.get()); + sInstance->mBaseProfileThreads.reset(); + } + sInstance->mExitProfiles.eraseIf( + [bufferRangeStart](const ExitProfile& aExitProfile) { + return aExitProfile.mBufferPositionAtGatherTime < bufferRangeStart; + }); + } + + static void AddBaseProfileThreads(PSLockRef aLock, + UniquePtr<char[]> aBaseProfileThreads) { + MOZ_ASSERT(sInstance); + DEBUG_LOG("AddBaseProfileThreads(%p)", aBaseProfileThreads.get()); + sInstance->mBaseProfileThreads = std::move(aBaseProfileThreads); + sInstance->mGeckoIndexWhenBaseProfileAdded = + ProfileBufferBlockIndex::CreateFromProfileBufferIndex( + profiler_get_core_buffer().GetState().mRangeEnd); + } + + static UniquePtr<char[]> MoveBaseProfileThreads(PSLockRef aLock) { + MOZ_ASSERT(sInstance); + + ClearExpiredExitProfiles(aLock); + + DEBUG_LOG("MoveBaseProfileThreads() - Consuming base profile %p", + sInstance->mBaseProfileThreads.get()); + return std::move(sInstance->mBaseProfileThreads); + } + + static void AddExitProfile(PSLockRef aLock, const nsACString& aExitProfile) { + MOZ_ASSERT(sInstance); + + ClearExpiredExitProfiles(aLock); + + MOZ_RELEASE_ASSERT(sInstance->mExitProfiles.append(ExitProfile{ + nsCString(aExitProfile), sInstance->mProfileBuffer.BufferRangeEnd()})); + } + + static Vector<nsCString> MoveExitProfiles(PSLockRef aLock) { + MOZ_ASSERT(sInstance); + + ClearExpiredExitProfiles(aLock); + + Vector<nsCString> profiles; + MOZ_RELEASE_ASSERT( + profiles.initCapacity(sInstance->mExitProfiles.length())); + for (auto& profile : sInstance->mExitProfiles) { + MOZ_RELEASE_ASSERT(profiles.append(std::move(profile.mJSON))); + } + sInstance->mExitProfiles.clear(); + return profiles; + } + +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + static void SetMemoryCounter(const BaseProfilerCount* aMemoryCounter) { + MOZ_ASSERT(sInstance); + + sInstance->mMemoryCounter = aMemoryCounter; + } + + static bool IsMemoryCounter(const BaseProfilerCount* aMemoryCounter) { + MOZ_ASSERT(sInstance); + + return sInstance->mMemoryCounter == aMemoryCounter; + } +#endif + + private: + // The singleton instance. + static ActivePS* sInstance; + + const TimeStamp mProfilingStartTime; + + // We need to track activity generations. If we didn't we could have the + // following scenario. + // + // - profiler_stop() locks gPSMutex, de-instantiates ActivePS, unlocks + // gPSMutex, deletes the SamplerThread (which does a join). + // + // - profiler_start() runs on a different thread, locks gPSMutex, + // re-instantiates ActivePS, unlocks gPSMutex -- all before the join + // completes. + // + // - SamplerThread::Run() locks gPSMutex, sees that ActivePS is instantiated, + // and continues as if the start/stop pair didn't occur. Also + // profiler_stop() is stuck, unable to finish. + // + // By checking ActivePS *and* the generation, we can avoid this scenario. + // sNextGeneration is used to track the next generation number; it is static + // because it must persist across different ActivePS instantiations. + const uint32_t mGeneration; + static uint32_t sNextGeneration; + + // The maximum number of entries in mProfileBuffer. + const PowerOfTwo32 mCapacity; + + // The maximum duration of entries in mProfileBuffer, in seconds. + const Maybe<double> mDuration; + + // The interval between samples, measured in milliseconds. + const double mInterval; + + // The profile features that are enabled. + const uint32_t mFeatures; + + // Substrings of names of threads we want to profile. + Vector<std::string> mFilters; + Vector<std::string> mFiltersLowered; + + // ID of the active browser screen's active tab. + // It's being used to determine the profiled tab. It's "0" if we failed to + // get the ID. + const uint64_t mActiveTabID; + + // The chunk manager used by `mProfileBuffer` below. + // May become null if it gets transferred ouf of the Gecko Profiler. + UniquePtr<ProfileBufferChunkManagerWithLocalLimit> mProfileBufferChunkManager; + + // The buffer into which all samples are recorded. + ProfileBuffer mProfileBuffer; + + // ProfiledThreadData objects for any threads that were profiled at any point + // during this run of the profiler: + // - mLiveProfiledThreads contains all threads that are still registered, and + // - mDeadProfiledThreads contains all threads that have already been + // unregistered but for which there is still data in the profile buffer. + Vector<LiveProfiledThreadData> mLiveProfiledThreads; + Vector<UniquePtr<ProfiledThreadData>> mDeadProfiledThreads; + + // Info on all the dead pages. + // Registered pages are being moved to this array after unregistration. + // We are keeping them in case we need them in the profile data. + // We are removing them when we ensure that we won't need them anymore. + Vector<RefPtr<PageInformation>> mDeadProfiledPages; + + // Used to collect process CPU utilization values, if the feature is on. + ProcessCPUCounter* mMaybeProcessCPUCounter; + + // Used to collect power use data, if the power feature is on. + PowerCounters* mMaybePowerCounters; + + // Used to collect cpu frequency, if the CPU frequency feature is on. + ProfilerCPUFreq* mMaybeCPUFreq; + + // The current sampler thread. This class is not responsible for destroying + // the SamplerThread object; the Destroy() method returns it so the caller + // can destroy it. + SamplerThread* const mSamplerThread; + + // Is the profiler fully paused? + bool mIsPaused; + + // Is the profiler periodic sampling paused? + bool mIsSamplingPaused; + + // Optional startup profile thread array from BaseProfiler. + UniquePtr<char[]> mBaseProfileThreads; + ProfileBufferBlockIndex mGeckoIndexWhenBaseProfileAdded; + + struct ExitProfile { + nsCString mJSON; + uint64_t mBufferPositionAtGatherTime; + }; + Vector<ExitProfile> mExitProfiles; + +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + Atomic<const BaseProfilerCount*> mMemoryCounter; +#endif +}; + +ActivePS* ActivePS::sInstance = nullptr; +uint32_t ActivePS::sNextGeneration = 0; + +#undef PS_GET +#undef PS_GET_LOCKLESS +#undef PS_GET_AND_SET + +using ProfilerStateChangeMutex = + mozilla::baseprofiler::detail::BaseProfilerMutex; +using ProfilerStateChangeLock = + mozilla::baseprofiler::detail::BaseProfilerAutoLock; +static ProfilerStateChangeMutex gProfilerStateChangeMutex; + +struct IdentifiedProfilingStateChangeCallback { + ProfilingStateSet mProfilingStateSet; + ProfilingStateChangeCallback mProfilingStateChangeCallback; + uintptr_t mUniqueIdentifier; + + explicit IdentifiedProfilingStateChangeCallback( + ProfilingStateSet aProfilingStateSet, + ProfilingStateChangeCallback&& aProfilingStateChangeCallback, + uintptr_t aUniqueIdentifier) + : mProfilingStateSet(aProfilingStateSet), + mProfilingStateChangeCallback(aProfilingStateChangeCallback), + mUniqueIdentifier(aUniqueIdentifier) {} +}; +using IdentifiedProfilingStateChangeCallbackUPtr = + UniquePtr<IdentifiedProfilingStateChangeCallback>; + +static Vector<IdentifiedProfilingStateChangeCallbackUPtr> + mIdentifiedProfilingStateChangeCallbacks; + +void profiler_add_state_change_callback( + ProfilingStateSet aProfilingStateSet, + ProfilingStateChangeCallback&& aCallback, + uintptr_t aUniqueIdentifier /* = 0 */) { + MOZ_ASSERT(!PSAutoLock::IsLockedOnCurrentThread()); + ProfilerStateChangeLock lock(gProfilerStateChangeMutex); + +#ifdef DEBUG + // Check if a non-zero id is not already used. Bug forgive it in non-DEBUG + // builds; in the worst case they may get removed too early. + if (aUniqueIdentifier != 0) { + for (const IdentifiedProfilingStateChangeCallbackUPtr& idedCallback : + mIdentifiedProfilingStateChangeCallbacks) { + MOZ_ASSERT(idedCallback->mUniqueIdentifier != aUniqueIdentifier); + } + } +#endif // DEBUG + + if (aProfilingStateSet.contains(ProfilingState::AlreadyActive) && + profiler_is_active()) { + aCallback(ProfilingState::AlreadyActive); + } + + (void)mIdentifiedProfilingStateChangeCallbacks.append( + MakeUnique<IdentifiedProfilingStateChangeCallback>( + aProfilingStateSet, std::move(aCallback), aUniqueIdentifier)); +} + +// Remove the callback with the given identifier. +void profiler_remove_state_change_callback(uintptr_t aUniqueIdentifier) { + MOZ_ASSERT(aUniqueIdentifier != 0); + if (aUniqueIdentifier == 0) { + // Forgive zero in non-DEBUG builds. + return; + } + + MOZ_ASSERT(!PSAutoLock::IsLockedOnCurrentThread()); + ProfilerStateChangeLock lock(gProfilerStateChangeMutex); + + mIdentifiedProfilingStateChangeCallbacks.eraseIf( + [aUniqueIdentifier]( + const IdentifiedProfilingStateChangeCallbackUPtr& aIdedCallback) { + if (aIdedCallback->mUniqueIdentifier != aUniqueIdentifier) { + return false; + } + if (aIdedCallback->mProfilingStateSet.contains( + ProfilingState::RemovingCallback)) { + aIdedCallback->mProfilingStateChangeCallback( + ProfilingState::RemovingCallback); + } + return true; + }); +} + +static void invoke_profiler_state_change_callbacks( + ProfilingState aProfilingState) { + MOZ_ASSERT(!PSAutoLock::IsLockedOnCurrentThread()); + ProfilerStateChangeLock lock(gProfilerStateChangeMutex); + + for (const IdentifiedProfilingStateChangeCallbackUPtr& idedCallback : + mIdentifiedProfilingStateChangeCallbacks) { + if (idedCallback->mProfilingStateSet.contains(aProfilingState)) { + idedCallback->mProfilingStateChangeCallback(aProfilingState); + } + } +} + +Atomic<uint32_t, MemoryOrdering::Relaxed> RacyFeatures::sActiveAndFeatures(0); + +// The name of the main thread. +static const char* const kMainThreadName = "GeckoMain"; + +//////////////////////////////////////////////////////////////////////// +// BEGIN sampling/unwinding code + +// Additional registers that have to be saved when thread is paused. +#if defined(GP_PLAT_x86_linux) || defined(GP_PLAT_x86_android) || \ + defined(GP_ARCH_x86) +# define UNWINDING_REGS_HAVE_ECX_EDX +#elif defined(GP_PLAT_amd64_linux) || defined(GP_PLAT_amd64_android) || \ + defined(GP_PLAT_amd64_freebsd) || defined(GP_ARCH_amd64) || \ + defined(__x86_64__) +# define UNWINDING_REGS_HAVE_R10_R12 +#elif defined(GP_PLAT_arm_linux) || defined(GP_PLAT_arm_android) +# define UNWINDING_REGS_HAVE_LR_R7 +#elif defined(GP_PLAT_arm64_linux) || defined(GP_PLAT_arm64_android) || \ + defined(GP_PLAT_arm64_freebsd) || defined(GP_ARCH_arm64) || \ + defined(__aarch64__) +# define UNWINDING_REGS_HAVE_LR_R11 +#endif + +// The registers used for stack unwinding and a few other sampling purposes. +// The ctor does nothing; users are responsible for filling in the fields. +class Registers { + public: + Registers() + : mPC{nullptr}, + mSP{nullptr}, + mFP{nullptr} +#if defined(UNWINDING_REGS_HAVE_ECX_EDX) + , + mEcx{nullptr}, + mEdx{nullptr} +#elif defined(UNWINDING_REGS_HAVE_R10_R12) + , + mR10{nullptr}, + mR12{nullptr} +#elif defined(UNWINDING_REGS_HAVE_LR_R7) + , + mLR{nullptr}, + mR7{nullptr} +#elif defined(UNWINDING_REGS_HAVE_LR_R11) + , + mLR{nullptr}, + mR11{nullptr} +#endif + { + } + + void Clear() { memset(this, 0, sizeof(*this)); } + + // These fields are filled in by + // Sampler::SuspendAndSampleAndResumeThread() for periodic and backtrace + // samples, and by REGISTERS_SYNC_POPULATE for synchronous samples. + Address mPC; // Instruction pointer. + Address mSP; // Stack pointer. + Address mFP; // Frame pointer. +#if defined(UNWINDING_REGS_HAVE_ECX_EDX) + Address mEcx; // Temp for return address. + Address mEdx; // Temp for frame pointer. +#elif defined(UNWINDING_REGS_HAVE_R10_R12) + Address mR10; // Temp for return address. + Address mR12; // Temp for frame pointer. +#elif defined(UNWINDING_REGS_HAVE_LR_R7) + Address mLR; // ARM link register, or temp for return address. + Address mR7; // Temp for frame pointer. +#elif defined(UNWINDING_REGS_HAVE_LR_R11) + Address mLR; // ARM link register, or temp for return address. + Address mR11; // Temp for frame pointer. +#endif + +#if defined(GP_OS_linux) || defined(GP_OS_android) || defined(GP_OS_freebsd) + // This contains all the registers, which means it duplicates the four fields + // above. This is ok. + ucontext_t* mContext; // The context from the signal handler or below. + ucontext_t mContextSyncStorage; // Storage for sync stack unwinding. +#endif +}; + +// Setting MAX_NATIVE_FRAMES too high risks the unwinder wasting a lot of time +// looping on corrupted stacks. +static const size_t MAX_NATIVE_FRAMES = 1024; + +struct NativeStack { + void* mPCs[MAX_NATIVE_FRAMES]; + void* mSPs[MAX_NATIVE_FRAMES]; + size_t mCount; // Number of frames filled. + + NativeStack() : mPCs(), mSPs(), mCount(0) {} +}; + +Atomic<bool> WALKING_JS_STACK(false); + +struct AutoWalkJSStack { + bool walkAllowed; + + AutoWalkJSStack() : walkAllowed(false) { + walkAllowed = WALKING_JS_STACK.compareExchange(false, true); + } + + ~AutoWalkJSStack() { + if (walkAllowed) { + WALKING_JS_STACK = false; + } + } +}; + +class StackWalkControl { + public: + struct ResumePoint { + // If lost, the stack walker should resume at these values. + void* resumeSp; // If null, stop the walker here, don't resume again. + void* resumeBp; + void* resumePc; + }; + +#if ((defined(USE_MOZ_STACK_WALK) || defined(USE_FRAME_POINTER_STACK_WALK)) && \ + defined(GP_ARCH_amd64)) + public: + static constexpr bool scIsSupported = true; + + void Clear() { mResumePointCount = 0; } + + size_t ResumePointCount() const { return mResumePointCount; } + + static constexpr size_t MaxResumePointCount() { + return scMaxResumePointCount; + } + + // Add a resume point. Note that adding anything past MaxResumePointCount() + // would silently fail. In practice this means that stack walking may still + // lose native frames. + void AddResumePoint(ResumePoint&& aResumePoint) { + // If SP is null, we expect BP and PC to also be null. + MOZ_ASSERT_IF(!aResumePoint.resumeSp, !aResumePoint.resumeBp); + MOZ_ASSERT_IF(!aResumePoint.resumeSp, !aResumePoint.resumePc); + + // If BP and/or PC are not null, SP must not be null. (But we allow BP/PC to + // be null even if SP is not null.) + MOZ_ASSERT_IF(aResumePoint.resumeBp, aResumePoint.resumeSp); + MOZ_ASSERT_IF(aResumePoint.resumePc, aResumePoint.resumeSp); + + if (mResumePointCount < scMaxResumePointCount) { + mResumePoint[mResumePointCount] = std::move(aResumePoint); + ++mResumePointCount; + } + } + + // Only allow non-modifying range-for loops. + const ResumePoint* begin() const { return &mResumePoint[0]; } + const ResumePoint* end() const { return &mResumePoint[mResumePointCount]; } + + // Find the next resume point that would be a caller of the function with the + // given SP; i.e., the resume point with the closest resumeSp > aSp. + const ResumePoint* GetResumePointCallingSp(void* aSp) const { + const ResumePoint* callingResumePoint = nullptr; + for (const ResumePoint& resumePoint : *this) { + if (resumePoint.resumeSp && // This is a potential resume point. + resumePoint.resumeSp > aSp && // It is a caller of the given SP. + (!callingResumePoint || // This is the first candidate. + resumePoint.resumeSp < callingResumePoint->resumeSp) // Or better. + ) { + callingResumePoint = &resumePoint; + } + } + return callingResumePoint; + } + + private: + size_t mResumePointCount = 0; + static constexpr size_t scMaxResumePointCount = 32; + ResumePoint mResumePoint[scMaxResumePointCount]; + +#else + public: + static constexpr bool scIsSupported = false; + // Discarded constexpr-if statements are still checked during compilation, + // these declarations are necessary for that, even if not actually used. + void Clear(); + size_t ResumePointCount(); + static constexpr size_t MaxResumePointCount(); + void AddResumePoint(ResumePoint&& aResumePoint); + const ResumePoint* begin() const; + const ResumePoint* end() const; + const ResumePoint* GetResumePointCallingSp(void* aSp) const; +#endif +}; + +// Make a copy of the JS stack into a JSFrame array, and return the number of +// copied frames. +// This copy is necessary since, like the native stack, the JS stack is iterated +// youngest-to-oldest and we need to iterate oldest-to-youngest in MergeStacks. +static uint32_t ExtractJsFrames( + bool aIsSynchronous, + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + const Registers& aRegs, ProfilerStackCollector& aCollector, + JsFrameBuffer aJsFrames, StackWalkControl* aStackWalkControlIfSupported) { + MOZ_ASSERT(aJsFrames, + "ExtractJsFrames should only be called if there is a " + "JsFrameBuffer to fill."); + + uint32_t jsFramesCount = 0; + + // Only walk jit stack if profiling frame iterator is turned on. + JSContext* context = aThreadData.GetJSContext(); + if (context && JS::IsProfilingEnabledForContext(context)) { + AutoWalkJSStack autoWalkJSStack; + + if (autoWalkJSStack.walkAllowed) { + JS::ProfilingFrameIterator::RegisterState registerState; + registerState.pc = aRegs.mPC; + registerState.sp = aRegs.mSP; + registerState.fp = aRegs.mFP; +#if defined(UNWINDING_REGS_HAVE_ECX_EDX) + registerState.tempRA = aRegs.mEcx; + registerState.tempFP = aRegs.mEdx; +#elif defined(UNWINDING_REGS_HAVE_R10_R12) + registerState.tempRA = aRegs.mR10; + registerState.tempFP = aRegs.mR12; +#elif defined(UNWINDING_REGS_HAVE_LR_R7) + registerState.lr = aRegs.mLR; + registerState.tempFP = aRegs.mR7; +#elif defined(UNWINDING_REGS_HAVE_LR_R11) + registerState.lr = aRegs.mLR; + registerState.tempFP = aRegs.mR11; +#endif + + // Non-periodic sampling passes Nothing() as the buffer write position to + // ProfilingFrameIterator to avoid incorrectly resetting the buffer + // position of sampled JIT frames inside the JS engine. + Maybe<uint64_t> samplePosInBuffer; + if (!aIsSynchronous) { + // aCollector.SamplePositionInBuffer() will return Nothing() when + // profiler_suspend_and_sample_thread is called from the background hang + // reporter. + samplePosInBuffer = aCollector.SamplePositionInBuffer(); + } + + for (JS::ProfilingFrameIterator jsIter(context, registerState, + samplePosInBuffer); + !jsIter.done(); ++jsIter) { + if (aIsSynchronous || jsIter.isWasm()) { + jsFramesCount += + jsIter.extractStack(aJsFrames, jsFramesCount, MAX_JS_FRAMES); + if (jsFramesCount == MAX_JS_FRAMES) { + break; + } + } else { + Maybe<JS::ProfilingFrameIterator::Frame> frame = + jsIter.getPhysicalFrameWithoutLabel(); + if (frame.isSome()) { + aJsFrames[jsFramesCount++] = std::move(frame).ref(); + if (jsFramesCount == MAX_JS_FRAMES) { + break; + } + } + } + + if constexpr (StackWalkControl::scIsSupported) { + if (aStackWalkControlIfSupported) { + jsIter.getCppEntryRegisters().apply( + [&](const JS::ProfilingFrameIterator::RegisterState& + aCppEntry) { + StackWalkControl::ResumePoint resumePoint; + resumePoint.resumeSp = aCppEntry.sp; + resumePoint.resumeBp = aCppEntry.fp; + resumePoint.resumePc = aCppEntry.pc; + aStackWalkControlIfSupported->AddResumePoint( + std::move(resumePoint)); + }); + } + } else { + MOZ_ASSERT(!aStackWalkControlIfSupported, + "aStackWalkControlIfSupported should be null when " + "!StackWalkControl::scIsSupported"); + (void)aStackWalkControlIfSupported; + } + } + } + } + + return jsFramesCount; +} + +// Merges the profiling stack, native stack, and JS stack, outputting the +// details to aCollector. +static void MergeStacks( + uint32_t aFeatures, bool aIsSynchronous, + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + const Registers& aRegs, const NativeStack& aNativeStack, + ProfilerStackCollector& aCollector, JsFrame* aJsFrames, + uint32_t aJsFramesCount) { + // WARNING: this function runs within the profiler's "critical section". + // WARNING: this function might be called while the profiler is inactive, and + // cannot rely on ActivePS. + + MOZ_ASSERT_IF(!aJsFrames, aJsFramesCount == 0); + + const ProfilingStack& profilingStack = aThreadData.ProfilingStackCRef(); + const js::ProfilingStackFrame* profilingStackFrames = profilingStack.frames; + uint32_t profilingStackFrameCount = profilingStack.stackSize(); + + // While the profiling stack array is ordered oldest-to-youngest, the JS and + // native arrays are ordered youngest-to-oldest. We must add frames to aInfo + // oldest-to-youngest. Thus, iterate over the profiling stack forwards and JS + // and native arrays backwards. Note: this means the terminating condition + // jsIndex and nativeIndex is being < 0. + uint32_t profilingStackIndex = 0; + int32_t jsIndex = aJsFramesCount - 1; + int32_t nativeIndex = aNativeStack.mCount - 1; + + uint8_t* lastLabelFrameStackAddr = nullptr; + uint8_t* jitEndStackAddr = nullptr; + + // Iterate as long as there is at least one frame remaining. + while (profilingStackIndex != profilingStackFrameCount || jsIndex >= 0 || + nativeIndex >= 0) { + // There are 1 to 3 frames available. Find and add the oldest. + uint8_t* profilingStackAddr = nullptr; + uint8_t* jsStackAddr = nullptr; + uint8_t* nativeStackAddr = nullptr; + uint8_t* jsActivationAddr = nullptr; + + if (profilingStackIndex != profilingStackFrameCount) { + const js::ProfilingStackFrame& profilingStackFrame = + profilingStackFrames[profilingStackIndex]; + + if (profilingStackFrame.isLabelFrame() || + profilingStackFrame.isSpMarkerFrame()) { + lastLabelFrameStackAddr = (uint8_t*)profilingStackFrame.stackAddress(); + } + + // Skip any JS_OSR frames. Such frames are used when the JS interpreter + // enters a jit frame on a loop edge (via on-stack-replacement, or OSR). + // To avoid both the profiling stack frame and jit frame being recorded + // (and showing up twice), the interpreter marks the interpreter + // profiling stack frame as JS_OSR to ensure that it doesn't get counted. + if (profilingStackFrame.isOSRFrame()) { + profilingStackIndex++; + continue; + } + + MOZ_ASSERT(lastLabelFrameStackAddr); + profilingStackAddr = lastLabelFrameStackAddr; + } + + if (jsIndex >= 0) { + jsStackAddr = (uint8_t*)aJsFrames[jsIndex].stackAddress; + jsActivationAddr = (uint8_t*)aJsFrames[jsIndex].activation; + } + + if (nativeIndex >= 0) { + nativeStackAddr = (uint8_t*)aNativeStack.mSPs[nativeIndex]; + } + + // If there's a native stack frame which has the same SP as a profiling + // stack frame, pretend we didn't see the native stack frame. Ditto for a + // native stack frame which has the same SP as a JS stack frame. In effect + // this means profiling stack frames or JS frames trump conflicting native + // frames. + if (nativeStackAddr && (profilingStackAddr == nativeStackAddr || + jsStackAddr == nativeStackAddr)) { + nativeStackAddr = nullptr; + nativeIndex--; + MOZ_ASSERT(profilingStackAddr || jsStackAddr); + } + + // Sanity checks. + MOZ_ASSERT_IF(profilingStackAddr, + profilingStackAddr != jsStackAddr && + profilingStackAddr != nativeStackAddr); + MOZ_ASSERT_IF(jsStackAddr, jsStackAddr != profilingStackAddr && + jsStackAddr != nativeStackAddr); + MOZ_ASSERT_IF(nativeStackAddr, nativeStackAddr != profilingStackAddr && + nativeStackAddr != jsStackAddr); + + // Check to see if profiling stack frame is top-most. + if (profilingStackAddr > jsStackAddr && + profilingStackAddr > nativeStackAddr) { + MOZ_ASSERT(profilingStackIndex < profilingStackFrameCount); + const js::ProfilingStackFrame& profilingStackFrame = + profilingStackFrames[profilingStackIndex]; + + // Sp marker frames are just annotations and should not be recorded in + // the profile. + if (!profilingStackFrame.isSpMarkerFrame()) { + // The JIT only allows the top-most frame to have a nullptr pc. + MOZ_ASSERT_IF( + profilingStackFrame.isJsFrame() && profilingStackFrame.script() && + !profilingStackFrame.pc(), + &profilingStackFrame == + &profilingStack.frames[profilingStack.stackSize() - 1]); + if (aIsSynchronous && profilingStackFrame.categoryPair() == + JS::ProfilingCategoryPair::PROFILER) { + // For stacks captured synchronously (ie. marker stacks), stop + // walking the stack as soon as we enter the profiler category, + // to avoid showing profiler internal code in marker stacks. + return; + } + aCollector.CollectProfilingStackFrame(profilingStackFrame); + } + profilingStackIndex++; + continue; + } + + // Check to see if JS jit stack frame is top-most + if (jsStackAddr > nativeStackAddr) { + MOZ_ASSERT(jsIndex >= 0); + const JS::ProfilingFrameIterator::Frame& jsFrame = aJsFrames[jsIndex]; + jitEndStackAddr = (uint8_t*)jsFrame.endStackAddress; + // Stringifying non-wasm JIT frames is delayed until streaming time. To + // re-lookup the entry in the JitcodeGlobalTable, we need to store the + // JIT code address (OptInfoAddr) in the circular buffer. + // + // Note that we cannot do this when we are sychronously sampling the + // current thread; that is, when called from profiler_get_backtrace. The + // captured backtrace is usually externally stored for an indeterminate + // amount of time, such as in nsRefreshDriver. Problematically, the + // stored backtrace may be alive across a GC during which the profiler + // itself is disabled. In that case, the JS engine is free to discard its + // JIT code. This means that if we inserted such OptInfoAddr entries into + // the buffer, nsRefreshDriver would now be holding on to a backtrace + // with stale JIT code return addresses. + if (aIsSynchronous || + jsFrame.kind == JS::ProfilingFrameIterator::Frame_Wasm) { + aCollector.CollectWasmFrame(jsFrame.label); + } else if (jsFrame.kind == + JS::ProfilingFrameIterator::Frame_BaselineInterpreter) { + // Materialize a ProfilingStackFrame similar to the C++ Interpreter. We + // also set the IS_BLINTERP_FRAME flag to differentiate though. + JSScript* script = jsFrame.interpreterScript; + jsbytecode* pc = jsFrame.interpreterPC(); + js::ProfilingStackFrame stackFrame; + constexpr uint32_t ExtraFlags = + uint32_t(js::ProfilingStackFrame::Flags::IS_BLINTERP_FRAME); + stackFrame.initJsFrame<JS::ProfilingCategoryPair::JS_BaselineInterpret, + ExtraFlags>("", jsFrame.label, script, pc, + jsFrame.realmID); + aCollector.CollectProfilingStackFrame(stackFrame); + } else { + MOZ_ASSERT(jsFrame.kind == JS::ProfilingFrameIterator::Frame_Ion || + jsFrame.kind == JS::ProfilingFrameIterator::Frame_Baseline); + aCollector.CollectJitReturnAddr(jsFrame.returnAddress()); + } + + jsIndex--; + continue; + } + + // If we reach here, there must be a native stack frame and it must be the + // greatest frame. + if (nativeStackAddr && + // If the latest JS frame was JIT, this could be the native frame that + // corresponds to it. In that case, skip the native frame, because + // there's no need for the same frame to be present twice in the stack. + // The JS frame can be considered the symbolicated version of the native + // frame. + (!jitEndStackAddr || nativeStackAddr < jitEndStackAddr) && + // This might still be a JIT operation, check to make sure that is not + // in range of the NEXT JavaScript's stacks' activation address. + (!jsActivationAddr || nativeStackAddr > jsActivationAddr)) { + MOZ_ASSERT(nativeIndex >= 0); + void* addr = (void*)aNativeStack.mPCs[nativeIndex]; + aCollector.CollectNativeLeafAddr(addr); + } + if (nativeIndex >= 0) { + nativeIndex--; + } + } + + // Update the JS context with the current profile sample buffer generation. + // + // Only do this for periodic samples. We don't want to do this for + // synchronous samples, and we also don't want to do it for calls to + // profiler_suspend_and_sample_thread() from the background hang reporter - + // in that case, aCollector.BufferRangeStart() will return Nothing(). + if (!aIsSynchronous) { + aCollector.BufferRangeStart().apply( + [&aThreadData](uint64_t aBufferRangeStart) { + JSContext* context = aThreadData.GetJSContext(); + if (context) { + JS::SetJSContextProfilerSampleBufferRangeStart(context, + aBufferRangeStart); + } + }); + } +} + +#if defined(USE_FRAME_POINTER_STACK_WALK) || defined(USE_MOZ_STACK_WALK) +static void StackWalkCallback(uint32_t aFrameNumber, void* aPC, void* aSP, + void* aClosure) { + NativeStack* nativeStack = static_cast<NativeStack*>(aClosure); + MOZ_ASSERT(nativeStack->mCount < MAX_NATIVE_FRAMES); + nativeStack->mSPs[nativeStack->mCount] = aSP; + nativeStack->mPCs[nativeStack->mCount] = aPC; + nativeStack->mCount++; +} +#endif + +#if defined(USE_FRAME_POINTER_STACK_WALK) +static void DoFramePointerBacktrace( + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + const Registers& aRegs, NativeStack& aNativeStack, + StackWalkControl* aStackWalkControlIfSupported) { + // WARNING: this function runs within the profiler's "critical section". + // WARNING: this function might be called while the profiler is inactive, and + // cannot rely on ActivePS. + + // Make a local copy of the Registers, to allow modifications. + Registers regs = aRegs; + + // Start with the current function. We use 0 as the frame number here because + // the FramePointerStackWalk() call below will use 1..N. This is a bit weird + // but it doesn't matter because StackWalkCallback() doesn't use the frame + // number argument. + StackWalkCallback(/* frameNum */ 0, regs.mPC, regs.mSP, &aNativeStack); + + const void* const stackEnd = aThreadData.StackTop(); + + // This is to check forward-progress after using a resume point. + void* previousResumeSp = nullptr; + + for (;;) { + if (!(regs.mSP && regs.mSP <= regs.mFP && regs.mFP <= stackEnd)) { + break; + } + FramePointerStackWalk(StackWalkCallback, + uint32_t(MAX_NATIVE_FRAMES - aNativeStack.mCount), + &aNativeStack, reinterpret_cast<void**>(regs.mFP), + const_cast<void*>(stackEnd)); + + if constexpr (!StackWalkControl::scIsSupported) { + break; + } else { + if (aNativeStack.mCount >= MAX_NATIVE_FRAMES) { + // No room to add more frames. + break; + } + if (!aStackWalkControlIfSupported || + aStackWalkControlIfSupported->ResumePointCount() == 0) { + // No resume information. + break; + } + void* lastSP = aNativeStack.mSPs[aNativeStack.mCount - 1]; + if (previousResumeSp && + ((uintptr_t)lastSP <= (uintptr_t)previousResumeSp)) { + // No progress after the previous resume point. + break; + } + const StackWalkControl::ResumePoint* resumePoint = + aStackWalkControlIfSupported->GetResumePointCallingSp(lastSP); + if (!resumePoint) { + break; + } + void* sp = resumePoint->resumeSp; + if (!sp) { + // Null SP in a resume point means we stop here. + break; + } + void* pc = resumePoint->resumePc; + StackWalkCallback(/* frameNum */ aNativeStack.mCount, pc, sp, + &aNativeStack); + ++aNativeStack.mCount; + if (aNativeStack.mCount >= MAX_NATIVE_FRAMES) { + break; + } + // Prepare context to resume stack walking. + regs.mPC = (Address)pc; + regs.mSP = (Address)sp; + regs.mFP = (Address)resumePoint->resumeBp; + + previousResumeSp = sp; + } + } +} +#endif + +#if defined(USE_MOZ_STACK_WALK) +static void DoMozStackWalkBacktrace( + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + const Registers& aRegs, NativeStack& aNativeStack, + StackWalkControl* aStackWalkControlIfSupported) { + // WARNING: this function runs within the profiler's "critical section". + // WARNING: this function might be called while the profiler is inactive, and + // cannot rely on ActivePS. + + // Start with the current function. We use 0 as the frame number here because + // the MozStackWalkThread() call below will use 1..N. This is a bit weird but + // it doesn't matter because StackWalkCallback() doesn't use the frame number + // argument. + StackWalkCallback(/* frameNum */ 0, aRegs.mPC, aRegs.mSP, &aNativeStack); + + HANDLE thread = aThreadData.PlatformDataCRef().ProfiledThread(); + MOZ_ASSERT(thread); + + CONTEXT context_buf; + CONTEXT* context = nullptr; + if constexpr (StackWalkControl::scIsSupported) { + context = &context_buf; + memset(&context_buf, 0, sizeof(CONTEXT)); + context_buf.ContextFlags = CONTEXT_FULL; +# if defined(_M_AMD64) + context_buf.Rsp = (DWORD64)aRegs.mSP; + context_buf.Rbp = (DWORD64)aRegs.mFP; + context_buf.Rip = (DWORD64)aRegs.mPC; +# else + static_assert(!StackWalkControl::scIsSupported, + "Mismatched support between StackWalkControl and " + "DoMozStackWalkBacktrace"); +# endif + } else { + context = nullptr; + } + + // This is to check forward-progress after using a resume point. + void* previousResumeSp = nullptr; + + for (;;) { + MozStackWalkThread(StackWalkCallback, + uint32_t(MAX_NATIVE_FRAMES - aNativeStack.mCount), + &aNativeStack, thread, context); + + if constexpr (!StackWalkControl::scIsSupported) { + break; + } else { + if (aNativeStack.mCount >= MAX_NATIVE_FRAMES) { + // No room to add more frames. + break; + } + if (!aStackWalkControlIfSupported || + aStackWalkControlIfSupported->ResumePointCount() == 0) { + // No resume information. + break; + } + void* lastSP = aNativeStack.mSPs[aNativeStack.mCount - 1]; + if (previousResumeSp && + ((uintptr_t)lastSP <= (uintptr_t)previousResumeSp)) { + // No progress after the previous resume point. + break; + } + const StackWalkControl::ResumePoint* resumePoint = + aStackWalkControlIfSupported->GetResumePointCallingSp(lastSP); + if (!resumePoint) { + break; + } + void* sp = resumePoint->resumeSp; + if (!sp) { + // Null SP in a resume point means we stop here. + break; + } + void* pc = resumePoint->resumePc; + StackWalkCallback(/* frameNum */ aNativeStack.mCount, pc, sp, + &aNativeStack); + ++aNativeStack.mCount; + if (aNativeStack.mCount >= MAX_NATIVE_FRAMES) { + break; + } + // Prepare context to resume stack walking. + memset(&context_buf, 0, sizeof(CONTEXT)); + context_buf.ContextFlags = CONTEXT_FULL; +# if defined(_M_AMD64) + context_buf.Rsp = (DWORD64)sp; + context_buf.Rbp = (DWORD64)resumePoint->resumeBp; + context_buf.Rip = (DWORD64)pc; +# else + static_assert(!StackWalkControl::scIsSupported, + "Mismatched support between StackWalkControl and " + "DoMozStackWalkBacktrace"); +# endif + previousResumeSp = sp; + } + } +} +#endif + +#ifdef USE_EHABI_STACKWALK +static void DoEHABIBacktrace( + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + const Registers& aRegs, NativeStack& aNativeStack, + StackWalkControl* aStackWalkControlIfSupported) { + // WARNING: this function runs within the profiler's "critical section". + // WARNING: this function might be called while the profiler is inactive, and + // cannot rely on ActivePS. + + aNativeStack.mCount = EHABIStackWalk( + aRegs.mContext->uc_mcontext, const_cast<void*>(aThreadData.StackTop()), + aNativeStack.mSPs, aNativeStack.mPCs, MAX_NATIVE_FRAMES); + (void)aStackWalkControlIfSupported; // TODO: Implement. +} +#endif + +#ifdef USE_LUL_STACKWALK + +// See the comment at the callsite for why this function is necessary. +# if defined(MOZ_HAVE_ASAN_IGNORE) +MOZ_ASAN_IGNORE static void ASAN_memcpy(void* aDst, const void* aSrc, + size_t aLen) { + // The obvious thing to do here is call memcpy(). However, although + // ASAN_memcpy() is not instrumented by ASAN, memcpy() still is, and the + // false positive still manifests! So we must implement memcpy() ourselves + // within this function. + char* dst = static_cast<char*>(aDst); + const char* src = static_cast<const char*>(aSrc); + + for (size_t i = 0; i < aLen; i++) { + dst[i] = src[i]; + } +} +# endif + +static void DoLULBacktrace( + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + const Registers& aRegs, NativeStack& aNativeStack, + StackWalkControl* aStackWalkControlIfSupported) { + // WARNING: this function runs within the profiler's "critical section". + // WARNING: this function might be called while the profiler is inactive, and + // cannot rely on ActivePS. + + (void)aStackWalkControlIfSupported; // TODO: Implement. + + const mcontext_t* mc = &aRegs.mContext->uc_mcontext; + + lul::UnwindRegs startRegs; + memset(&startRegs, 0, sizeof(startRegs)); + +# if defined(GP_PLAT_amd64_linux) || defined(GP_PLAT_amd64_android) + startRegs.xip = lul::TaggedUWord(mc->gregs[REG_RIP]); + startRegs.xsp = lul::TaggedUWord(mc->gregs[REG_RSP]); + startRegs.xbp = lul::TaggedUWord(mc->gregs[REG_RBP]); +# elif defined(GP_PLAT_amd64_freebsd) + startRegs.xip = lul::TaggedUWord(mc->mc_rip); + startRegs.xsp = lul::TaggedUWord(mc->mc_rsp); + startRegs.xbp = lul::TaggedUWord(mc->mc_rbp); +# elif defined(GP_PLAT_arm_linux) || defined(GP_PLAT_arm_android) + startRegs.r15 = lul::TaggedUWord(mc->arm_pc); + startRegs.r14 = lul::TaggedUWord(mc->arm_lr); + startRegs.r13 = lul::TaggedUWord(mc->arm_sp); + startRegs.r12 = lul::TaggedUWord(mc->arm_ip); + startRegs.r11 = lul::TaggedUWord(mc->arm_fp); + startRegs.r7 = lul::TaggedUWord(mc->arm_r7); +# elif defined(GP_PLAT_arm64_linux) || defined(GP_PLAT_arm64_android) + startRegs.pc = lul::TaggedUWord(mc->pc); + startRegs.x29 = lul::TaggedUWord(mc->regs[29]); + startRegs.x30 = lul::TaggedUWord(mc->regs[30]); + startRegs.sp = lul::TaggedUWord(mc->sp); +# elif defined(GP_PLAT_arm64_freebsd) + startRegs.pc = lul::TaggedUWord(mc->mc_gpregs.gp_elr); + startRegs.x29 = lul::TaggedUWord(mc->mc_gpregs.gp_x[29]); + startRegs.x30 = lul::TaggedUWord(mc->mc_gpregs.gp_lr); + startRegs.sp = lul::TaggedUWord(mc->mc_gpregs.gp_sp); +# elif defined(GP_PLAT_x86_linux) || defined(GP_PLAT_x86_android) + startRegs.xip = lul::TaggedUWord(mc->gregs[REG_EIP]); + startRegs.xsp = lul::TaggedUWord(mc->gregs[REG_ESP]); + startRegs.xbp = lul::TaggedUWord(mc->gregs[REG_EBP]); +# elif defined(GP_PLAT_mips64_linux) + startRegs.pc = lul::TaggedUWord(mc->pc); + startRegs.sp = lul::TaggedUWord(mc->gregs[29]); + startRegs.fp = lul::TaggedUWord(mc->gregs[30]); +# else +# error "Unknown plat" +# endif + + // Copy up to N_STACK_BYTES from rsp-REDZONE upwards, but not going past the + // stack's registered top point. Do some basic validity checks too. This + // assumes that the TaggedUWord holding the stack pointer value is valid, but + // it should be, since it was constructed that way in the code just above. + + // We could construct |stackImg| so that LUL reads directly from the stack in + // question, rather than from a copy of it. That would reduce overhead and + // space use a bit. However, it gives a problem with dynamic analysis tools + // (ASan, TSan, Valgrind) which is that such tools will report invalid or + // racing memory accesses, and such accesses will be reported deep inside LUL. + // By taking a copy here, we can either sanitise the copy (for Valgrind) or + // copy it using an unchecked memcpy (for ASan, TSan). That way we don't have + // to try and suppress errors inside LUL. + // + // N_STACK_BYTES is set to 160KB. This is big enough to hold all stacks + // observed in some minutes of testing, whilst keeping the size of this + // function (DoNativeBacktrace)'s frame reasonable. Most stacks observed in + // practice are small, 4KB or less, and so the copy costs are insignificant + // compared to other profiler overhead. + // + // |stackImg| is allocated on this (the sampling thread's) stack. That + // implies that the frame for this function is at least N_STACK_BYTES large. + // In general it would be considered unacceptable to have such a large frame + // on a stack, but it only exists for the unwinder thread, and so is not + // expected to be a problem. Allocating it on the heap is troublesome because + // this function runs whilst the sampled thread is suspended, so any heap + // allocation risks deadlock. Allocating it as a global variable is not + // thread safe, which would be a problem if we ever allow multiple sampler + // threads. Hence allocating it on the stack seems to be the least-worst + // option. + + lul::StackImage stackImg; + + { +# if defined(GP_PLAT_amd64_linux) || defined(GP_PLAT_amd64_android) || \ + defined(GP_PLAT_amd64_freebsd) + uintptr_t rEDZONE_SIZE = 128; + uintptr_t start = startRegs.xsp.Value() - rEDZONE_SIZE; +# elif defined(GP_PLAT_arm_linux) || defined(GP_PLAT_arm_android) + uintptr_t rEDZONE_SIZE = 0; + uintptr_t start = startRegs.r13.Value() - rEDZONE_SIZE; +# elif defined(GP_PLAT_arm64_linux) || defined(GP_PLAT_arm64_android) || \ + defined(GP_PLAT_arm64_freebsd) + uintptr_t rEDZONE_SIZE = 0; + uintptr_t start = startRegs.sp.Value() - rEDZONE_SIZE; +# elif defined(GP_PLAT_x86_linux) || defined(GP_PLAT_x86_android) + uintptr_t rEDZONE_SIZE = 0; + uintptr_t start = startRegs.xsp.Value() - rEDZONE_SIZE; +# elif defined(GP_PLAT_mips64_linux) + uintptr_t rEDZONE_SIZE = 0; + uintptr_t start = startRegs.sp.Value() - rEDZONE_SIZE; +# else +# error "Unknown plat" +# endif + uintptr_t end = reinterpret_cast<uintptr_t>(aThreadData.StackTop()); + uintptr_t ws = sizeof(void*); + start &= ~(ws - 1); + end &= ~(ws - 1); + uintptr_t nToCopy = 0; + if (start < end) { + nToCopy = end - start; + if (nToCopy >= 1024u * 1024u) { + // start is abnormally far from end, possibly due to some special code + // that uses a separate stack elsewhere (e.g.: rr). In this case we just + // give up on this sample. + nToCopy = 0; + } else if (nToCopy > lul::N_STACK_BYTES) { + nToCopy = lul::N_STACK_BYTES; + } + } + MOZ_ASSERT(nToCopy <= lul::N_STACK_BYTES); + stackImg.mLen = nToCopy; + stackImg.mStartAvma = start; + if (nToCopy > 0) { + // If this is a vanilla memcpy(), ASAN makes the following complaint: + // + // ERROR: AddressSanitizer: stack-buffer-underflow ... + // ... + // HINT: this may be a false positive if your program uses some custom + // stack unwind mechanism or swapcontext + // + // This code is very much a custom stack unwind mechanism! So we use an + // alternative memcpy() implementation that is ignored by ASAN. +# if defined(MOZ_HAVE_ASAN_IGNORE) + ASAN_memcpy(&stackImg.mContents[0], (void*)start, nToCopy); +# else + memcpy(&stackImg.mContents[0], (void*)start, nToCopy); +# endif + (void)VALGRIND_MAKE_MEM_DEFINED(&stackImg.mContents[0], nToCopy); + } + } + + size_t framePointerFramesAcquired = 0; + lul::LUL* lul = CorePS::Lul(); + MOZ_RELEASE_ASSERT(lul); + lul->Unwind(reinterpret_cast<uintptr_t*>(aNativeStack.mPCs), + reinterpret_cast<uintptr_t*>(aNativeStack.mSPs), + &aNativeStack.mCount, &framePointerFramesAcquired, + MAX_NATIVE_FRAMES, &startRegs, &stackImg); + + // Update stats in the LUL stats object. Unfortunately this requires + // three global memory operations. + lul->mStats.mContext += 1; + lul->mStats.mCFI += aNativeStack.mCount - 1 - framePointerFramesAcquired; + lul->mStats.mFP += framePointerFramesAcquired; +} + +#endif + +#ifdef HAVE_NATIVE_UNWIND +static void DoNativeBacktrace( + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + const Registers& aRegs, NativeStack& aNativeStack, + StackWalkControl* aStackWalkControlIfSupported) { + // This method determines which stackwalker is used for periodic and + // synchronous samples. (Backtrace samples are treated differently, see + // profiler_suspend_and_sample_thread() for details). The only part of the + // ordering that matters is that LUL must precede FRAME_POINTER, because on + // Linux they can both be present. +# if defined(USE_LUL_STACKWALK) + DoLULBacktrace(aThreadData, aRegs, aNativeStack, + aStackWalkControlIfSupported); +# elif defined(USE_EHABI_STACKWALK) + DoEHABIBacktrace(aThreadData, aRegs, aNativeStack, + aStackWalkControlIfSupported); +# elif defined(USE_FRAME_POINTER_STACK_WALK) + DoFramePointerBacktrace(aThreadData, aRegs, aNativeStack, + aStackWalkControlIfSupported); +# elif defined(USE_MOZ_STACK_WALK) + DoMozStackWalkBacktrace(aThreadData, aRegs, aNativeStack, + aStackWalkControlIfSupported); +# else +# error "Invalid configuration" +# endif +} +#endif + +// Writes some components shared by periodic and synchronous profiles to +// ActivePS's ProfileBuffer. (This should only be called from DoSyncSample() +// and DoPeriodicSample().) +// +// The grammar for entry sequences is in a comment above +// ProfileBuffer::StreamSamplesToJSON. +static inline void DoSharedSample( + bool aIsSynchronous, uint32_t aFeatures, + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + JsFrame* aJsFrames, const Registers& aRegs, uint64_t aSamplePos, + uint64_t aBufferRangeStart, ProfileBuffer& aBuffer, + StackCaptureOptions aCaptureOptions = StackCaptureOptions::Full) { + // WARNING: this function runs within the profiler's "critical section". + + MOZ_ASSERT(!aBuffer.IsThreadSafe(), + "Mutexes cannot be used inside this critical section"); + + ProfileBufferCollector collector(aBuffer, aSamplePos, aBufferRangeStart); + StackWalkControl* stackWalkControlIfSupported = nullptr; +#if defined(HAVE_NATIVE_UNWIND) + const bool captureNative = ProfilerFeature::HasStackWalk(aFeatures) && + aCaptureOptions == StackCaptureOptions::Full; + StackWalkControl stackWalkControl; + if constexpr (StackWalkControl::scIsSupported) { + if (captureNative) { + stackWalkControlIfSupported = &stackWalkControl; + } + } +#endif // defined(HAVE_NATIVE_UNWIND) + const uint32_t jsFramesCount = + aJsFrames ? ExtractJsFrames(aIsSynchronous, aThreadData, aRegs, collector, + aJsFrames, stackWalkControlIfSupported) + : 0; + NativeStack nativeStack; +#if defined(HAVE_NATIVE_UNWIND) + if (captureNative) { + DoNativeBacktrace(aThreadData, aRegs, nativeStack, + stackWalkControlIfSupported); + + MergeStacks(aFeatures, aIsSynchronous, aThreadData, aRegs, nativeStack, + collector, aJsFrames, jsFramesCount); + } else +#endif + { + MergeStacks(aFeatures, aIsSynchronous, aThreadData, aRegs, nativeStack, + collector, aJsFrames, jsFramesCount); + + // We can't walk the whole native stack, but we can record the top frame. + if (aCaptureOptions == StackCaptureOptions::Full) { + aBuffer.AddEntry(ProfileBufferEntry::NativeLeafAddr((void*)aRegs.mPC)); + } + } +} + +// Writes the components of a synchronous sample to the given ProfileBuffer. +static void DoSyncSample( + uint32_t aFeatures, + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + const TimeStamp& aNow, const Registers& aRegs, ProfileBuffer& aBuffer, + StackCaptureOptions aCaptureOptions) { + // WARNING: this function runs within the profiler's "critical section". + + MOZ_ASSERT(aCaptureOptions != StackCaptureOptions::NoStack, + "DoSyncSample should not be called when no capture is needed"); + + const uint64_t bufferRangeStart = aBuffer.BufferRangeStart(); + + const uint64_t samplePos = + aBuffer.AddThreadIdEntry(aThreadData.Info().ThreadId()); + + TimeDuration delta = aNow - CorePS::ProcessStartTime(); + aBuffer.AddEntry(ProfileBufferEntry::Time(delta.ToMilliseconds())); + + if (!aThreadData.GetJSContext()) { + // No JSContext, there is no JS frame buffer (and no need for it). + DoSharedSample(/* aIsSynchronous = */ true, aFeatures, aThreadData, + /* aJsFrames = */ nullptr, aRegs, samplePos, + bufferRangeStart, aBuffer, aCaptureOptions); + } else { + // JSContext is present, we need to lock the thread data to access the JS + // frame buffer. + ThreadRegistration::WithOnThreadRef([&](ThreadRegistration::OnThreadRef + aOnThreadRef) { + aOnThreadRef.WithConstLockedRWOnThread( + [&](const ThreadRegistration::LockedRWOnThread& aLockedThreadData) { + DoSharedSample(/* aIsSynchronous = */ true, aFeatures, aThreadData, + aLockedThreadData.GetJsFrameBuffer(), aRegs, + samplePos, bufferRangeStart, aBuffer, + aCaptureOptions); + }); + }); + } +} + +// Writes the components of a periodic sample to ActivePS's ProfileBuffer. +// The ThreadId entry is already written in the main ProfileBuffer, its location +// is `aSamplePos`, we can write the rest to `aBuffer` (which may be different). +static inline void DoPeriodicSample( + PSLockRef aLock, + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + const Registers& aRegs, uint64_t aSamplePos, uint64_t aBufferRangeStart, + ProfileBuffer& aBuffer) { + // WARNING: this function runs within the profiler's "critical section". + + MOZ_RELEASE_ASSERT(ActivePS::Exists(aLock)); + + JsFrameBuffer& jsFrames = CorePS::JsFrames(aLock); + DoSharedSample(/* aIsSynchronous = */ false, ActivePS::Features(aLock), + aThreadData, jsFrames, aRegs, aSamplePos, aBufferRangeStart, + aBuffer); +} + +#undef UNWINDING_REGS_HAVE_ECX_EDX +#undef UNWINDING_REGS_HAVE_R10_R12 +#undef UNWINDING_REGS_HAVE_LR_R7 +#undef UNWINDING_REGS_HAVE_LR_R11 + +// END sampling/unwinding code +//////////////////////////////////////////////////////////////////////// + +//////////////////////////////////////////////////////////////////////// +// BEGIN saving/streaming code + +const static uint64_t kJS_MAX_SAFE_UINTEGER = +9007199254740991ULL; + +static int64_t SafeJSInteger(uint64_t aValue) { + return aValue <= kJS_MAX_SAFE_UINTEGER ? int64_t(aValue) : -1; +} + +static void AddSharedLibraryInfoToStream(JSONWriter& aWriter, + const SharedLibrary& aLib) { + aWriter.StartObjectElement(); + aWriter.IntProperty("start", SafeJSInteger(aLib.GetStart())); + aWriter.IntProperty("end", SafeJSInteger(aLib.GetEnd())); + aWriter.IntProperty("offset", SafeJSInteger(aLib.GetOffset())); + aWriter.StringProperty("name", NS_ConvertUTF16toUTF8(aLib.GetModuleName())); + aWriter.StringProperty("path", NS_ConvertUTF16toUTF8(aLib.GetModulePath())); + aWriter.StringProperty("debugName", + NS_ConvertUTF16toUTF8(aLib.GetDebugName())); + aWriter.StringProperty("debugPath", + NS_ConvertUTF16toUTF8(aLib.GetDebugPath())); + aWriter.StringProperty("breakpadId", aLib.GetBreakpadId()); + aWriter.StringProperty("codeId", aLib.GetCodeId()); + aWriter.StringProperty("arch", aLib.GetArch()); + aWriter.EndObject(); +} + +void AppendSharedLibraries(JSONWriter& aWriter, + const SharedLibraryInfo& aInfo) { + for (size_t i = 0; i < aInfo.GetSize(); i++) { + AddSharedLibraryInfoToStream(aWriter, aInfo.GetEntry(i)); + } +} + +static void StreamCategories(SpliceableJSONWriter& aWriter) { + // Same order as ProfilingCategory. Format: + // [ + // { + // name: "Idle", + // color: "transparent", + // subcategories: ["Other"], + // }, + // { + // name: "Other", + // color: "grey", + // subcategories: [ + // "JSM loading", + // "Subprocess launching", + // "DLL loading" + // ] + // }, + // ... + // ] + +#define CATEGORY_JSON_BEGIN_CATEGORY(name, labelAsString, color) \ + aWriter.Start(); \ + aWriter.StringProperty("name", labelAsString); \ + aWriter.StringProperty("color", color); \ + aWriter.StartArrayProperty("subcategories"); +#define CATEGORY_JSON_SUBCATEGORY(supercategory, name, labelAsString) \ + aWriter.StringElement(labelAsString); +#define CATEGORY_JSON_END_CATEGORY \ + aWriter.EndArray(); \ + aWriter.EndObject(); + + MOZ_PROFILING_CATEGORY_LIST(CATEGORY_JSON_BEGIN_CATEGORY, + CATEGORY_JSON_SUBCATEGORY, + CATEGORY_JSON_END_CATEGORY) + +#undef CATEGORY_JSON_BEGIN_CATEGORY +#undef CATEGORY_JSON_SUBCATEGORY +#undef CATEGORY_JSON_END_CATEGORY +} + +static void StreamMarkerSchema(SpliceableJSONWriter& aWriter) { + // Get an array view with all registered marker-type-specific functions. + base_profiler_markers_detail::Streaming::LockedMarkerTypeFunctionsList + markerTypeFunctionsArray; + // List of streamed marker names, this is used to spot duplicates. + std::set<std::string> names; + // Stream the display schema for each different one. (Duplications may come + // from the same code potentially living in different libraries.) + for (const auto& markerTypeFunctions : markerTypeFunctionsArray) { + auto name = markerTypeFunctions.mMarkerTypeNameFunction(); + // std::set.insert(T&&) returns a pair, its `second` is true if the element + // was actually inserted (i.e., it was not there yet.) + const bool didInsert = + names.insert(std::string(name.data(), name.size())).second; + if (didInsert) { + markerTypeFunctions.mMarkerSchemaFunction().Stream(aWriter, name); + } + } + + // Now stream the Rust marker schemas. Passing the names set as a void pointer + // as well, so we can continue checking if the schemes are added already in + // the Rust side. + profiler::ffi::gecko_profiler_stream_marker_schemas( + &aWriter, static_cast<void*>(&names)); +} + +// Some meta information that is better recorded before streaming the profile. +// This is *not* intended to be cached, as some values could change between +// profiling sessions. +struct PreRecordedMetaInformation { + bool mAsyncStacks; + + // This struct should only live on the stack, so it's fine to use Auto + // strings. + nsAutoCString mHttpPlatform; + nsAutoCString mHttpOscpu; + nsAutoCString mHttpMisc; + + nsAutoCString mRuntimeABI; + nsAutoCString mRuntimeToolkit; + + nsAutoCString mAppInfoProduct; + nsAutoCString mAppInfoAppBuildID; + nsAutoCString mAppInfoSourceURL; + + int32_t mProcessInfoCpuCount; + int32_t mProcessInfoCpuCores; + nsAutoCString mProcessInfoCpuName; +}; + +// This function should be called out of the profiler lock. +// It gathers non-trivial data that doesn't require the profiler to stop, or for +// which the request could theoretically deadlock if the profiler is locked. +static PreRecordedMetaInformation PreRecordMetaInformation( + bool aShutdown = false) { + MOZ_ASSERT(!PSAutoLock::IsLockedOnCurrentThread()); + + PreRecordedMetaInformation info = {}; // Aggregate-init all fields. + + if (!NS_IsMainThread()) { + // Leave these properties out if we're not on the main thread. + // At the moment, the only case in which this function is called on a + // background thread is if we're in a content process and are going to + // send this profile to the parent process. In that case, the parent + // process profile's "meta" object already has the rest of the properties, + // and the parent process profile is dumped on that process's main thread. + return info; + } + + info.mAsyncStacks = + !aShutdown && Preferences::GetBool("javascript.options.asyncstack"); + + nsresult res; + + if (nsCOMPtr<nsIHttpProtocolHandler> http = + do_GetService(NS_NETWORK_PROTOCOL_CONTRACTID_PREFIX "http", &res); + !NS_FAILED(res) && http) { + Unused << http->GetPlatform(info.mHttpPlatform); + +#if defined(GP_OS_darwin) + // On Mac, the http "oscpu" is capped at 10.15, so we need to get the real + // OS version directly. + int major = 0; + int minor = 0; + int bugfix = 0; + nsCocoaFeatures::GetSystemVersion(major, minor, bugfix); + if (major != 0) { + info.mHttpOscpu.AppendLiteral("macOS "); + info.mHttpOscpu.AppendInt(major); + info.mHttpOscpu.AppendLiteral("."); + info.mHttpOscpu.AppendInt(minor); + info.mHttpOscpu.AppendLiteral("."); + info.mHttpOscpu.AppendInt(bugfix); + } else +#endif +#if defined(GP_OS_windows) + // On Windows, the http "oscpu" is capped at Windows 10, so we need to get + // the real OS version directly. + OSVERSIONINFO ovi = {sizeof(OSVERSIONINFO)}; + if (GetVersionEx(&ovi)) { + info.mHttpOscpu.AppendLiteral("Windows "); + // The major version returned for Windows 11 is 10, but we can + // identify it from the build number. + info.mHttpOscpu.AppendInt( + ovi.dwBuildNumber >= 22000 ? 11 : int32_t(ovi.dwMajorVersion)); + info.mHttpOscpu.AppendLiteral("."); + info.mHttpOscpu.AppendInt(int32_t(ovi.dwMinorVersion)); +# if defined(_ARM64_) + info.mHttpOscpu.AppendLiteral(" Arm64"); +# endif + info.mHttpOscpu.AppendLiteral("; build="); + info.mHttpOscpu.AppendInt(int32_t(ovi.dwBuildNumber)); + } else +#endif + { + Unused << http->GetOscpu(info.mHttpOscpu); + } + + // Firefox version is capped to 109.0 in the http "misc" field due to some + // webcompat issues (Bug 1805967). We need to put the real version instead. + info.mHttpMisc.AssignLiteral("rv:"); + info.mHttpMisc.AppendLiteral(MOZILLA_UAVERSION); + } + + if (nsCOMPtr<nsIXULRuntime> runtime = + do_GetService("@mozilla.org/xre/runtime;1"); + runtime) { + Unused << runtime->GetXPCOMABI(info.mRuntimeABI); + Unused << runtime->GetWidgetToolkit(info.mRuntimeToolkit); + } + + if (nsCOMPtr<nsIXULAppInfo> appInfo = + do_GetService("@mozilla.org/xre/app-info;1"); + appInfo) { + Unused << appInfo->GetName(info.mAppInfoProduct); + Unused << appInfo->GetAppBuildID(info.mAppInfoAppBuildID); + Unused << appInfo->GetSourceURL(info.mAppInfoSourceURL); + } + + ProcessInfo processInfo = {}; // Aggregate-init all fields to false/zeroes. + if (NS_SUCCEEDED(CollectProcessInfo(processInfo))) { + info.mProcessInfoCpuCount = processInfo.cpuCount; + info.mProcessInfoCpuCores = processInfo.cpuCores; + info.mProcessInfoCpuName = processInfo.cpuName; + } + + return info; +} + +// Implemented in platform-specific cpps, to add object properties describing +// the units of CPU measurements in samples. +static void StreamMetaPlatformSampleUnits(PSLockRef aLock, + SpliceableJSONWriter& aWriter); + +static void StreamMetaJSCustomObject( + PSLockRef aLock, SpliceableJSONWriter& aWriter, bool aIsShuttingDown, + const PreRecordedMetaInformation& aPreRecordedMetaInformation) { + MOZ_RELEASE_ASSERT(CorePS::Exists() && ActivePS::Exists(aLock)); + + aWriter.IntProperty("version", GECKO_PROFILER_FORMAT_VERSION); + + // The "startTime" field holds the number of milliseconds since midnight + // January 1, 1970 GMT. This grotty code computes (Now - (Now - + // ProcessStartTime)) to convert CorePS::ProcessStartTime() into that form. + // Note: This is the only absolute time in the profile! All other timestamps + // are relative to this startTime. + TimeDuration delta = TimeStamp::Now() - CorePS::ProcessStartTime(); + aWriter.DoubleProperty( + "startTime", + static_cast<double>(PR_Now() / 1000.0 - delta.ToMilliseconds())); + + aWriter.DoubleProperty("profilingStartTime", (ActivePS::ProfilingStartTime() - + CorePS::ProcessStartTime()) + .ToMilliseconds()); + + if (const TimeStamp contentEarliestTime = + ActivePS::Buffer(aLock) + .UnderlyingChunkedBuffer() + .GetEarliestChunkStartTimeStamp(); + !contentEarliestTime.IsNull()) { + aWriter.DoubleProperty( + "contentEarliestTime", + (contentEarliestTime - CorePS::ProcessStartTime()).ToMilliseconds()); + } else { + aWriter.NullProperty("contentEarliestTime"); + } + + const double profilingEndTime = profiler_time(); + aWriter.DoubleProperty("profilingEndTime", profilingEndTime); + + if (aIsShuttingDown) { + aWriter.DoubleProperty("shutdownTime", profilingEndTime); + } else { + aWriter.NullProperty("shutdownTime"); + } + + aWriter.StartArrayProperty("categories"); + StreamCategories(aWriter); + aWriter.EndArray(); + + aWriter.StartArrayProperty("markerSchema"); + StreamMarkerSchema(aWriter); + aWriter.EndArray(); + + ActivePS::WriteActiveConfiguration(aLock, aWriter, + MakeStringSpan("configuration")); + + if (!NS_IsMainThread()) { + // Leave the rest of the properties out if we're not on the main thread. + // At the moment, the only case in which this function is called on a + // background thread is if we're in a content process and are going to + // send this profile to the parent process. In that case, the parent + // process profile's "meta" object already has the rest of the properties, + // and the parent process profile is dumped on that process's main thread. + return; + } + + aWriter.DoubleProperty("interval", ActivePS::Interval(aLock)); + aWriter.IntProperty("stackwalk", ActivePS::FeatureStackWalk(aLock)); + +#ifdef DEBUG + aWriter.IntProperty("debug", 1); +#else + aWriter.IntProperty("debug", 0); +#endif + + aWriter.IntProperty("gcpoison", JS::IsGCPoisoning() ? 1 : 0); + + aWriter.IntProperty("asyncstack", aPreRecordedMetaInformation.mAsyncStacks); + + aWriter.IntProperty("processType", XRE_GetProcessType()); + + aWriter.StringProperty("updateChannel", MOZ_STRINGIFY(MOZ_UPDATE_CHANNEL)); + + if (!aPreRecordedMetaInformation.mHttpPlatform.IsEmpty()) { + aWriter.StringProperty("platform", + aPreRecordedMetaInformation.mHttpPlatform); + } + if (!aPreRecordedMetaInformation.mHttpOscpu.IsEmpty()) { + aWriter.StringProperty("oscpu", aPreRecordedMetaInformation.mHttpOscpu); + } + if (!aPreRecordedMetaInformation.mHttpMisc.IsEmpty()) { + aWriter.StringProperty("misc", aPreRecordedMetaInformation.mHttpMisc); + } + + if (!aPreRecordedMetaInformation.mRuntimeABI.IsEmpty()) { + aWriter.StringProperty("abi", aPreRecordedMetaInformation.mRuntimeABI); + } + if (!aPreRecordedMetaInformation.mRuntimeToolkit.IsEmpty()) { + aWriter.StringProperty("toolkit", + aPreRecordedMetaInformation.mRuntimeToolkit); + } + + if (!aPreRecordedMetaInformation.mAppInfoProduct.IsEmpty()) { + aWriter.StringProperty("product", + aPreRecordedMetaInformation.mAppInfoProduct); + } + if (!aPreRecordedMetaInformation.mAppInfoAppBuildID.IsEmpty()) { + aWriter.StringProperty("appBuildID", + aPreRecordedMetaInformation.mAppInfoAppBuildID); + } + if (!aPreRecordedMetaInformation.mAppInfoSourceURL.IsEmpty()) { + aWriter.StringProperty("sourceURL", + aPreRecordedMetaInformation.mAppInfoSourceURL); + } + + if (!aPreRecordedMetaInformation.mProcessInfoCpuName.IsEmpty()) { + aWriter.StringProperty("CPUName", + aPreRecordedMetaInformation.mProcessInfoCpuName); + } + if (aPreRecordedMetaInformation.mProcessInfoCpuCores > 0) { + aWriter.IntProperty("physicalCPUs", + aPreRecordedMetaInformation.mProcessInfoCpuCores); + } + if (aPreRecordedMetaInformation.mProcessInfoCpuCount > 0) { + aWriter.IntProperty("logicalCPUs", + aPreRecordedMetaInformation.mProcessInfoCpuCount); + } + +#if defined(GP_OS_android) + jni::String::LocalRef deviceInformation = + java::GeckoJavaSampler::GetDeviceInformation(); + aWriter.StringProperty("device", deviceInformation->ToCString()); +#endif + + aWriter.StartObjectProperty("sampleUnits"); + { + aWriter.StringProperty("time", "ms"); + aWriter.StringProperty("eventDelay", "ms"); + StreamMetaPlatformSampleUnits(aLock, aWriter); + } + aWriter.EndObject(); + + // We should avoid collecting extension metadata for profiler when there is no + // observer service, since a ExtensionPolicyService could not be created then. + if (nsCOMPtr<nsIObserverService> os = services::GetObserverService()) { + aWriter.StartObjectProperty("extensions"); + { + { + JSONSchemaWriter schema(aWriter); + schema.WriteField("id"); + schema.WriteField("name"); + schema.WriteField("baseURL"); + } + + aWriter.StartArrayProperty("data"); + { + nsTArray<RefPtr<WebExtensionPolicy>> exts; + ExtensionPolicyService::GetSingleton().GetAll(exts); + + for (auto& ext : exts) { + aWriter.StartArrayElement(); + + nsAutoString id; + ext->GetId(id); + aWriter.StringElement(NS_ConvertUTF16toUTF8(id)); + + aWriter.StringElement(NS_ConvertUTF16toUTF8(ext->Name())); + + auto url = ext->GetURL(u""_ns); + if (url.isOk()) { + aWriter.StringElement(NS_ConvertUTF16toUTF8(url.unwrap())); + } + + aWriter.EndArray(); + } + } + aWriter.EndArray(); + } + aWriter.EndObject(); + } +} + +static void StreamPages(PSLockRef aLock, SpliceableJSONWriter& aWriter) { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + ActivePS::DiscardExpiredPages(aLock); + for (const auto& page : ActivePS::ProfiledPages(aLock)) { + page->StreamJSON(aWriter); + } +} + +#if defined(GP_OS_android) +template <int N> +static bool StartsWith(const nsACString& string, const char (&prefix)[N]) { + if (N - 1 > string.Length()) { + return false; + } + return memcmp(string.Data(), prefix, N - 1) == 0; +} + +static JS::ProfilingCategoryPair InferJavaCategory(nsACString& aName) { + if (aName.EqualsLiteral("android.os.MessageQueue.nativePollOnce()")) { + return JS::ProfilingCategoryPair::IDLE; + } + if (aName.EqualsLiteral("java.lang.Object.wait()")) { + return JS::ProfilingCategoryPair::JAVA_BLOCKED; + } + if (StartsWith(aName, "android.") || StartsWith(aName, "com.android.")) { + return JS::ProfilingCategoryPair::JAVA_ANDROID; + } + if (StartsWith(aName, "mozilla.") || StartsWith(aName, "org.mozilla.")) { + return JS::ProfilingCategoryPair::JAVA_MOZILLA; + } + if (StartsWith(aName, "java.") || StartsWith(aName, "sun.") || + StartsWith(aName, "com.sun.")) { + return JS::ProfilingCategoryPair::JAVA_LANGUAGE; + } + if (StartsWith(aName, "kotlin.") || StartsWith(aName, "kotlinx.")) { + return JS::ProfilingCategoryPair::JAVA_KOTLIN; + } + if (StartsWith(aName, "androidx.")) { + return JS::ProfilingCategoryPair::JAVA_ANDROIDX; + } + return JS::ProfilingCategoryPair::OTHER; +} + +// Marker type for Java markers without any details. +struct JavaMarker { + static constexpr Span<const char> MarkerTypeName() { + return MakeStringSpan("Java"); + } + static void StreamJSONMarkerData( + baseprofiler::SpliceableJSONWriter& aWriter) {} + static MarkerSchema MarkerTypeDisplay() { + using MS = MarkerSchema; + MS schema{MS::Location::TimelineOverview, MS::Location::MarkerChart, + MS::Location::MarkerTable}; + schema.SetAllLabels("{marker.name}"); + return schema; + } +}; + +// Marker type for Java markers with a detail field. +struct JavaMarkerWithDetails { + static constexpr Span<const char> MarkerTypeName() { + return MakeStringSpan("JavaWithDetails"); + } + static void StreamJSONMarkerData(baseprofiler::SpliceableJSONWriter& aWriter, + const ProfilerString8View& aText) { + // This (currently) needs to be called "name" to be searchable on the + // front-end. + aWriter.StringProperty("name", aText); + } + static MarkerSchema MarkerTypeDisplay() { + using MS = MarkerSchema; + MS schema{MS::Location::TimelineOverview, MS::Location::MarkerChart, + MS::Location::MarkerTable}; + schema.SetTooltipLabel("{marker.name}"); + schema.SetChartLabel("{marker.data.name}"); + schema.SetTableLabel("{marker.name} - {marker.data.name}"); + schema.AddKeyLabelFormatSearchable("name", "Details", MS::Format::String, + MS::Searchable::Searchable); + return schema; + } +}; + +static void CollectJavaThreadProfileData( + nsTArray<java::GeckoJavaSampler::ThreadInfo::LocalRef>& javaThreads, + ProfileBuffer& aProfileBuffer) { + // Retrieve metadata about the threads. + const auto threadCount = java::GeckoJavaSampler::GetRegisteredThreadCount(); + for (int i = 0; i < threadCount; i++) { + javaThreads.AppendElement( + java::GeckoJavaSampler::GetRegisteredThreadInfo(i)); + } + + // locked_profiler_start uses sample count is 1000 for Java thread. + // This entry size is enough now, but we might have to estimate it + // if we can customize it + // Pass the samples + int sampleId = 0; + while (true) { + const auto threadId = java::GeckoJavaSampler::GetThreadId(sampleId); + double sampleTime = java::GeckoJavaSampler::GetSampleTime(sampleId); + if (threadId == 0 || sampleTime == 0.0) { + break; + } + + aProfileBuffer.AddThreadIdEntry(ProfilerThreadId::FromNumber(threadId)); + aProfileBuffer.AddEntry(ProfileBufferEntry::Time(sampleTime)); + int frameId = 0; + while (true) { + jni::String::LocalRef frameName = + java::GeckoJavaSampler::GetFrameName(sampleId, frameId++); + if (!frameName) { + break; + } + nsCString frameNameString = frameName->ToCString(); + + auto categoryPair = InferJavaCategory(frameNameString); + aProfileBuffer.CollectCodeLocation("", frameNameString.get(), 0, 0, + Nothing(), Nothing(), + Some(categoryPair)); + } + sampleId++; + } + + // Pass the markers now + while (true) { + // Gets the data from the Android UI thread only. + java::GeckoJavaSampler::Marker::LocalRef marker = + java::GeckoJavaSampler::PollNextMarker(); + if (!marker) { + // All markers are transferred. + break; + } + + // Get all the marker information from the Java thread using JNI. + const auto threadId = ProfilerThreadId::FromNumber(marker->GetThreadId()); + nsCString markerName = marker->GetMarkerName()->ToCString(); + jni::String::LocalRef text = marker->GetMarkerText(); + TimeStamp startTime = + CorePS::ProcessStartTime() + + TimeDuration::FromMilliseconds(marker->GetStartTime()); + + double endTimeMs = marker->GetEndTime(); + // A marker can be either a duration with start and end, or a point in time + // with only startTime. If endTime is 0, this means it's a point in time. + TimeStamp endTime = endTimeMs == 0 + ? startTime + : CorePS::ProcessStartTime() + + TimeDuration::FromMilliseconds(endTimeMs); + MarkerTiming timing = endTimeMs == 0 + ? MarkerTiming::InstantAt(startTime) + : MarkerTiming::Interval(startTime, endTime); + + if (!text) { + // This marker doesn't have a text. + AddMarkerToBuffer(aProfileBuffer.UnderlyingChunkedBuffer(), markerName, + geckoprofiler::category::JAVA_ANDROID, + {MarkerThreadId(threadId), std::move(timing)}, + JavaMarker{}); + } else { + // This marker has a text. + AddMarkerToBuffer(aProfileBuffer.UnderlyingChunkedBuffer(), markerName, + geckoprofiler::category::JAVA_ANDROID, + {MarkerThreadId(threadId), std::move(timing)}, + JavaMarkerWithDetails{}, text->ToCString()); + } + } +} +#endif + +UniquePtr<ProfilerCodeAddressService> +profiler_code_address_service_for_presymbolication() { + static const bool preSymbolicate = []() { + const char* symbolicate = getenv("MOZ_PROFILER_SYMBOLICATE"); + return symbolicate && symbolicate[0] != '\0'; + }(); + return preSymbolicate ? MakeUnique<ProfilerCodeAddressService>() : nullptr; +} + +static ProfilerResult<ProfileGenerationAdditionalInformation> +locked_profiler_stream_json_for_this_process( + PSLockRef aLock, SpliceableJSONWriter& aWriter, double aSinceTime, + const PreRecordedMetaInformation& aPreRecordedMetaInformation, + bool aIsShuttingDown, ProfilerCodeAddressService* aService, + mozilla::ProgressLogger aProgressLogger) { + LOG("locked_profiler_stream_json_for_this_process"); + +#ifdef DEBUG + PRIntervalTime slowWithSleeps = 0; + if (!XRE_IsParentProcess()) { + for (const auto& filter : ActivePS::Filters(aLock)) { + if (filter == "test-debug-child-slow-json") { + LOG("test-debug-child-slow-json"); + // There are 10 slow-downs below, each will sleep 250ms, for a total of + // 2.5s, which should trigger the first progress request after 1s, and + // the next progress which will have advanced further, so this profile + // shouldn't get dropped. + slowWithSleeps = PR_MillisecondsToInterval(250); + } else if (filter == "test-debug-child-very-slow-json") { + LOG("test-debug-child-very-slow-json"); + // Wait for more than 2s without any progress, which should get this + // profile discarded. + PR_Sleep(PR_SecondsToInterval(5)); + } + } + } +# define SLOW_DOWN_FOR_TESTING() \ + if (slowWithSleeps != 0) { \ + DEBUG_LOG("progress=%.0f%%, sleep...", \ + aProgressLogger.GetGlobalProgress().ToDouble() * 100.0); \ + PR_Sleep(slowWithSleeps); \ + } +#else // #ifdef DEBUG +# define SLOW_DOWN_FOR_TESTING() /* No slow-downs */ +#endif // #ifdef DEBUG #else + + MOZ_RELEASE_ASSERT(CorePS::Exists() && ActivePS::Exists(aLock)); + + AUTO_PROFILER_STATS(locked_profiler_stream_json_for_this_process); + + const double collectionStartMs = profiler_time(); + + ProfileBuffer& buffer = ActivePS::Buffer(aLock); + + aProgressLogger.SetLocalProgress(1_pc, "Locked profile buffer"); + + SLOW_DOWN_FOR_TESTING(); + + // If there is a set "Window length", discard older data. + Maybe<double> durationS = ActivePS::Duration(aLock); + if (durationS.isSome()) { + const double durationStartMs = collectionStartMs - *durationS * 1000; + buffer.DiscardSamplesBeforeTime(durationStartMs); + } + aProgressLogger.SetLocalProgress(2_pc, "Discarded old data"); + + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + SLOW_DOWN_FOR_TESTING(); + +#if defined(GP_OS_android) + // Java thread profile data should be collected before serializing the meta + // object. This is because Java thread adds some markers with marker schema + // objects. And these objects should be added before the serialization of the + // `profile.meta.markerSchema` array, so these marker schema objects can also + // be serialized properly. That's why java thread profile data needs to be + // done before everything. + + // We are allocating it chunk by chunk. So this will not allocate 64 MiB + // at once. This size should be more than enough for java threads. + // This buffer is being created for each process but Android has + // relatively fewer processes compared to desktop, so it's okay here. + mozilla::ProfileBufferChunkManagerWithLocalLimit javaChunkManager( + 64 * 1024 * 1024, 1024 * 1024); + ProfileChunkedBuffer javaBufferManager( + ProfileChunkedBuffer::ThreadSafety::WithoutMutex, javaChunkManager); + ProfileBuffer javaBuffer(javaBufferManager); + + nsTArray<java::GeckoJavaSampler::ThreadInfo::LocalRef> javaThreads; + + if (ActivePS::FeatureJava(aLock)) { + CollectJavaThreadProfileData(javaThreads, javaBuffer); + aProgressLogger.SetLocalProgress(3_pc, "Collected Java thread"); + } +#endif + + // Put shared library info + aWriter.StartArrayProperty("libs"); + SharedLibraryInfo sharedLibraryInfo = SharedLibraryInfo::GetInfoForSelf(); + sharedLibraryInfo.SortByAddress(); + AppendSharedLibraries(aWriter, sharedLibraryInfo); + aWriter.EndArray(); + aProgressLogger.SetLocalProgress(4_pc, "Wrote library information"); + + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + SLOW_DOWN_FOR_TESTING(); + + // Put meta data + aWriter.StartObjectProperty("meta"); + { + StreamMetaJSCustomObject(aLock, aWriter, aIsShuttingDown, + aPreRecordedMetaInformation); + } + aWriter.EndObject(); + aProgressLogger.SetLocalProgress(5_pc, "Wrote profile metadata"); + + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + SLOW_DOWN_FOR_TESTING(); + + // Put page data + aWriter.StartArrayProperty("pages"); + { StreamPages(aLock, aWriter); } + aWriter.EndArray(); + aProgressLogger.SetLocalProgress(6_pc, "Wrote pages"); + + buffer.StreamProfilerOverheadToJSON( + aWriter, CorePS::ProcessStartTime(), aSinceTime, + aProgressLogger.CreateSubLoggerTo(10_pc, "Wrote profiler overheads")); + + buffer.StreamCountersToJSON( + aWriter, CorePS::ProcessStartTime(), aSinceTime, + aProgressLogger.CreateSubLoggerTo(14_pc, "Wrote counters")); + + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + SLOW_DOWN_FOR_TESTING(); + + // Lists the samples for each thread profile + aWriter.StartArrayProperty("threads"); + { + ActivePS::DiscardExpiredDeadProfiledThreads(aLock); + aProgressLogger.SetLocalProgress(15_pc, "Discarded expired profiles"); + + ThreadRegistry::LockedRegistry lockedRegistry; + ActivePS::ProfiledThreadList threads = + ActivePS::ProfiledThreads(lockedRegistry, aLock); + + const uint32_t threadCount = uint32_t(threads.length()); + + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + SLOW_DOWN_FOR_TESTING(); + + // Prepare the streaming context for each thread. + ProcessStreamingContext processStreamingContext( + threadCount, aWriter.SourceFailureLatch(), CorePS::ProcessStartTime(), + aSinceTime); + for (auto&& [i, progressLogger] : aProgressLogger.CreateLoopSubLoggersTo( + 20_pc, threadCount, "Preparing thread streaming contexts...")) { + ActivePS::ProfiledThreadListElement& thread = threads[i]; + MOZ_RELEASE_ASSERT(thread.mProfiledThreadData); + processStreamingContext.AddThreadStreamingContext( + *thread.mProfiledThreadData, buffer, thread.mJSContext, aService, + std::move(progressLogger)); + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + } + + SLOW_DOWN_FOR_TESTING(); + + // Read the buffer once, and extract all samples and markers that the + // context expects. + buffer.StreamSamplesAndMarkersToJSON( + processStreamingContext, aProgressLogger.CreateSubLoggerTo( + "Processing samples and markers...", 80_pc, + "Processed samples and markers")); + + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + SLOW_DOWN_FOR_TESTING(); + + // Stream each thread from the pre-filled context. + ThreadStreamingContext* const contextListBegin = + processStreamingContext.begin(); + MOZ_ASSERT(uint32_t(processStreamingContext.end() - contextListBegin) == + threadCount); + for (auto&& [i, progressLogger] : aProgressLogger.CreateLoopSubLoggersTo( + 92_pc, threadCount, "Streaming threads...")) { + ThreadStreamingContext& threadStreamingContext = contextListBegin[i]; + threadStreamingContext.FinalizeWriter(); + threadStreamingContext.mProfiledThreadData.StreamJSON( + std::move(threadStreamingContext), aWriter, + CorePS::ProcessName(aLock), CorePS::ETLDplus1(aLock), + CorePS::ProcessStartTime(), aService, std::move(progressLogger)); + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + } + aProgressLogger.SetLocalProgress(92_pc, "Wrote samples and markers"); + +#if defined(GP_OS_android) + if (ActivePS::FeatureJava(aLock)) { + for (java::GeckoJavaSampler::ThreadInfo::LocalRef& threadInfo : + javaThreads) { + ProfiledThreadData threadData(ThreadRegistrationInfo{ + threadInfo->GetName()->ToCString().BeginReading(), + ProfilerThreadId::FromNumber(threadInfo->GetId()), false, + CorePS::ProcessStartTime()}); + + threadData.StreamJSON( + javaBuffer, nullptr, aWriter, CorePS::ProcessName(aLock), + CorePS::ETLDplus1(aLock), CorePS::ProcessStartTime(), aSinceTime, + nullptr, + aProgressLogger.CreateSubLoggerTo("Streaming Java thread...", 96_pc, + "Streamed Java thread")); + } + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + } else { + aProgressLogger.SetLocalProgress(96_pc, "No Java thread"); + } +#endif + + UniquePtr<char[]> baseProfileThreads = + ActivePS::MoveBaseProfileThreads(aLock); + if (baseProfileThreads) { + aWriter.Splice(MakeStringSpan(baseProfileThreads.get())); + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + aProgressLogger.SetLocalProgress(97_pc, "Wrote baseprofiler data"); + } else { + aProgressLogger.SetLocalProgress(97_pc, "No baseprofiler data"); + } + } + aWriter.EndArray(); + + SLOW_DOWN_FOR_TESTING(); + + aWriter.StartArrayProperty("pausedRanges"); + { + buffer.StreamPausedRangesToJSON( + aWriter, aSinceTime, + aProgressLogger.CreateSubLoggerTo("Streaming pauses...", 99_pc, + "Streamed pauses")); + } + aWriter.EndArray(); + + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + + ProfilingLog::Access([&](Json::Value& aProfilingLogObject) { + aProfilingLogObject[Json::StaticString{ + "profilingLogEnd" TIMESTAMP_JSON_SUFFIX}] = ProfilingLog::Timestamp(); + + aWriter.StartObjectProperty("profilingLog"); + { + nsAutoCString pid; + pid.AppendInt(int64_t(profiler_current_process_id().ToNumber())); + Json::String logString = ToCompactString(aProfilingLogObject); + aWriter.SplicedJSONProperty(pid, logString); + } + aWriter.EndObject(); + }); + + const double collectionEndMs = profiler_time(); + + // Record timestamps for the collection into the buffer, so that consumers + // know why we didn't collect any samples for its duration. + // We put these entries into the buffer after we've collected the profile, + // so they'll be visible for the *next* profile collection (if they haven't + // been overwritten due to buffer wraparound by then). + buffer.AddEntry(ProfileBufferEntry::CollectionStart(collectionStartMs)); + buffer.AddEntry(ProfileBufferEntry::CollectionEnd(collectionEndMs)); + +#ifdef DEBUG + if (slowWithSleeps != 0) { + LOG("locked_profiler_stream_json_for_this_process done"); + } +#endif // DEBUG + + return ProfileGenerationAdditionalInformation{std::move(sharedLibraryInfo)}; +} + +// Keep this internal function non-static, so it may be used by tests. +ProfilerResult<ProfileGenerationAdditionalInformation> +do_profiler_stream_json_for_this_process( + SpliceableJSONWriter& aWriter, double aSinceTime, bool aIsShuttingDown, + ProfilerCodeAddressService* aService, + mozilla::ProgressLogger aProgressLogger) { + LOG("profiler_stream_json_for_this_process"); + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + const auto preRecordedMetaInformation = PreRecordMetaInformation(); + + aProgressLogger.SetLocalProgress(2_pc, "PreRecordMetaInformation done"); + + if (profiler_is_active()) { + invoke_profiler_state_change_callbacks(ProfilingState::GeneratingProfile); + } + + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + return Err(ProfilerError::IsInactive); + } + + ProfileGenerationAdditionalInformation additionalInfo; + MOZ_TRY_VAR( + additionalInfo, + locked_profiler_stream_json_for_this_process( + lock, aWriter, aSinceTime, preRecordedMetaInformation, + aIsShuttingDown, aService, + aProgressLogger.CreateSubLoggerFromTo( + 3_pc, "locked_profiler_stream_json_for_this_process started", + 100_pc, "locked_profiler_stream_json_for_this_process done"))); + + if (aWriter.Failed()) { + return Err(ProfilerError::JsonGenerationFailed); + } + return additionalInfo; +} + +ProfilerResult<ProfileGenerationAdditionalInformation> +profiler_stream_json_for_this_process(SpliceableJSONWriter& aWriter, + double aSinceTime, bool aIsShuttingDown, + ProfilerCodeAddressService* aService, + mozilla::ProgressLogger aProgressLogger) { + MOZ_RELEASE_ASSERT( + !XRE_IsParentProcess() || NS_IsMainThread(), + "In the parent process, profiles should only be generated from the main " + "thread, otherwise they will be incomplete."); + + ProfileGenerationAdditionalInformation additionalInfo; + MOZ_TRY_VAR(additionalInfo, do_profiler_stream_json_for_this_process( + aWriter, aSinceTime, aIsShuttingDown, + aService, std::move(aProgressLogger))); + + return additionalInfo; +} + +// END saving/streaming code +//////////////////////////////////////////////////////////////////////// + +static char FeatureCategory(uint32_t aFeature) { + if (aFeature & DefaultFeatures()) { + if (aFeature & AvailableFeatures()) { + return 'D'; + } + return 'd'; + } + + if (aFeature & StartupExtraDefaultFeatures()) { + if (aFeature & AvailableFeatures()) { + return 'S'; + } + return 's'; + } + + if (aFeature & AvailableFeatures()) { + return '-'; + } + return 'x'; +} + +static void PrintUsage() { + MOZ_RELEASE_ASSERT(NS_IsMainThread()); + + printf( + "\n" + "Profiler environment variable usage:\n" + "\n" + " MOZ_PROFILER_HELP\n" + " If set to any value, prints this message.\n" + " Use MOZ_BASE_PROFILER_HELP for BaseProfiler help.\n" + "\n" + " MOZ_LOG\n" + " Enables logging. The levels of logging available are\n" + " 'prof:3' (least verbose), 'prof:4', 'prof:5' (most verbose).\n" + "\n" + " MOZ_PROFILER_STARTUP\n" + " If set to any value other than '' or '0'/'N'/'n', starts the\n" + " profiler immediately on start-up.\n" + " Useful if you want profile code that runs very early.\n" + "\n" + " MOZ_PROFILER_STARTUP_ENTRIES=<%u..%u>\n" + " If MOZ_PROFILER_STARTUP is set, specifies the number of entries per\n" + " process in the profiler's circular buffer when the profiler is first\n" + " started.\n" + " If unset, the platform default is used:\n" + " %u entries per process, or %u when MOZ_PROFILER_STARTUP is set.\n" + " (%u bytes per entry -> %u or %u total bytes per process)\n" + " Optional units in bytes: KB, KiB, MB, MiB, GB, GiB\n" + "\n" + " MOZ_PROFILER_STARTUP_DURATION=<1..>\n" + " If MOZ_PROFILER_STARTUP is set, specifies the maximum life time of\n" + " entries in the the profiler's circular buffer when the profiler is\n" + " first started, in seconds.\n" + " If unset, the life time of the entries will only be restricted by\n" + " MOZ_PROFILER_STARTUP_ENTRIES (or its default value), and no\n" + " additional time duration restriction will be applied.\n" + "\n" + " MOZ_PROFILER_STARTUP_INTERVAL=<1..%d>\n" + " If MOZ_PROFILER_STARTUP is set, specifies the sample interval,\n" + " measured in milliseconds, when the profiler is first started.\n" + " If unset, the platform default is used.\n" + "\n" + " MOZ_PROFILER_STARTUP_FEATURES_BITFIELD=<Number>\n" + " If MOZ_PROFILER_STARTUP is set, specifies the profiling features, as\n" + " the integer value of the features bitfield.\n" + " If unset, the value from MOZ_PROFILER_STARTUP_FEATURES is used.\n" + "\n" + " MOZ_PROFILER_STARTUP_FEATURES=<Features>\n" + " If MOZ_PROFILER_STARTUP is set, specifies the profiling features, as\n" + " a comma-separated list of strings.\n" + " Ignored if MOZ_PROFILER_STARTUP_FEATURES_BITFIELD is set.\n" + " If unset, the platform default is used.\n" + "\n" + " Features: (x=unavailable, D/d=default/unavailable,\n" + " S/s=MOZ_PROFILER_STARTUP extra default/unavailable)\n", + unsigned(scMinimumBufferEntries), unsigned(scMaximumBufferEntries), + unsigned(PROFILER_DEFAULT_ENTRIES.Value()), + unsigned(PROFILER_DEFAULT_STARTUP_ENTRIES.Value()), + unsigned(scBytesPerEntry), + unsigned(PROFILER_DEFAULT_ENTRIES.Value() * scBytesPerEntry), + unsigned(PROFILER_DEFAULT_STARTUP_ENTRIES.Value() * scBytesPerEntry), + PROFILER_MAX_INTERVAL); + +#define PRINT_FEATURE(n_, str_, Name_, desc_) \ + printf(" %c %7u: \"%s\" (%s)\n", FeatureCategory(ProfilerFeature::Name_), \ + ProfilerFeature::Name_, str_, desc_); + + PROFILER_FOR_EACH_FEATURE(PRINT_FEATURE) + +#undef PRINT_FEATURE + + printf( + " - \"default\" (All above D+S defaults)\n" + "\n" + " MOZ_PROFILER_STARTUP_FILTERS=<Filters>\n" + " If MOZ_PROFILER_STARTUP is set, specifies the thread filters, as a\n" + " comma-separated list of strings. A given thread will be sampled if\n" + " any of the filters is a case-insensitive substring of the thread\n" + " name. If unset, a default is used.\n" + "\n" + " MOZ_PROFILER_STARTUP_ACTIVE_TAB_ID=<Number>\n" + " This variable is used to propagate the activeTabID of\n" + " the profiler init params to subprocesses.\n" + "\n" + " MOZ_PROFILER_SHUTDOWN=<Filename>\n" + " If set, the profiler saves a profile to the named file on shutdown.\n" + " If the Filename contains \"%%p\", this will be replaced with the'\n" + " process id of the parent process.\n" + "\n" + " MOZ_PROFILER_SYMBOLICATE\n" + " If set, the profiler will pre-symbolicate profiles.\n" + " *Note* This will add a significant pause when gathering data, and\n" + " is intended mainly for local development.\n" + "\n" + " MOZ_PROFILER_LUL_TEST\n" + " If set to any value, runs LUL unit tests at startup.\n" + "\n" + " This platform %s native unwinding.\n" + "\n", +#if defined(HAVE_NATIVE_UNWIND) + "supports" +#else + "does not support" +#endif + ); +} + +//////////////////////////////////////////////////////////////////////// +// BEGIN Sampler + +#if defined(GP_OS_linux) || defined(GP_OS_android) +struct SigHandlerCoordinator; +#endif + +// Sampler performs setup and teardown of the state required to sample with the +// profiler. Sampler may exist when ActivePS is not present. +// +// SuspendAndSampleAndResumeThread must only be called from a single thread, +// and must not sample the thread it is being called from. A separate Sampler +// instance must be used for each thread which wants to capture samples. + +// WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING +// +// With the exception of SamplerThread, all Sampler objects must be Disable-d +// before releasing the lock which was used to create them. This avoids races +// on linux with the SIGPROF signal handler. + +class Sampler { + public: + // Sets up the profiler such that it can begin sampling. + explicit Sampler(PSLockRef aLock); + + // Disable the sampler, restoring it to its previous state. This must be + // called once, and only once, before the Sampler is destroyed. + void Disable(PSLockRef aLock); + + // This method suspends and resumes the samplee thread. It calls the passed-in + // function-like object aProcessRegs (passing it a populated |const + // Registers&| arg) while the samplee thread is suspended. Note that + // the aProcessRegs function must be very careful not to do anything that + // requires a lock, since we may have interrupted the thread at any point. + // As an example, you can't call TimeStamp::Now() since on windows it + // takes a lock on the performance counter. + // + // Func must be a function-like object of type `void()`. + template <typename Func> + void SuspendAndSampleAndResumeThread( + PSLockRef aLock, + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + const TimeStamp& aNow, const Func& aProcessRegs); + + private: +#if defined(GP_OS_linux) || defined(GP_OS_android) || defined(GP_OS_freebsd) + // Used to restore the SIGPROF handler when ours is removed. + struct sigaction mOldSigprofHandler; + + // This process' ID. Needed as an argument for tgkill in + // SuspendAndSampleAndResumeThread. + ProfilerProcessId mMyPid; + + // The sampler thread's ID. Used to assert that it is not sampling itself, + // which would lead to deadlock. + ProfilerThreadId mSamplerTid; + + public: + // This is the one-and-only variable used to communicate between the sampler + // thread and the samplee thread's signal handler. It's static because the + // samplee thread's signal handler is static. + static struct SigHandlerCoordinator* sSigHandlerCoordinator; +#endif +}; + +// END Sampler +//////////////////////////////////////////////////////////////////////// + +// Platform-specific function that retrieves per-thread CPU measurements. +static RunningTimes GetThreadRunningTimesDiff( + PSLockRef aLock, + ThreadRegistration::UnlockedRWForLockedProfiler& aThreadData); +// Platform-specific function that *may* discard CPU measurements since the +// previous call to GetThreadRunningTimesDiff, if the way to suspend threads on +// this platform may add running times to that thread. +// No-op otherwise, if suspending a thread doesn't make it work. +static void DiscardSuspendedThreadRunningTimes( + PSLockRef aLock, + ThreadRegistration::UnlockedRWForLockedProfiler& aThreadData); + +// Platform-specific function that retrieves process CPU measurements. +static RunningTimes GetProcessRunningTimesDiff( + PSLockRef aLock, RunningTimes& aPreviousRunningTimesToBeUpdated); + +// Template function to be used by `GetThreadRunningTimesDiff()` (unless some +// platform has a better way to achieve this). +// It help perform CPU measurements and tie them to a timestamp, such that the +// measurements and timestamp are very close together. +// This is necessary, because the relative CPU usage is computed by dividing +// consecutive CPU measurements by their timestamp difference; if there was an +// unexpected big gap, it could skew this computation and produce impossible +// spikes that would hide the rest of the data. See bug 1685938 for more info. +// Note that this may call the measurement function more than once; it is +// assumed to normally be fast. +// This was verified experimentally, but there is currently no regression +// testing for it; see follow-up bug 1687402. +template <typename GetCPURunningTimesFunction> +RunningTimes GetRunningTimesWithTightTimestamp( + GetCPURunningTimesFunction&& aGetCPURunningTimesFunction) { + // Once per process, compute a threshold over which running times and their + // timestamp is considered too far apart. + static const TimeDuration scMaxRunningTimesReadDuration = [&]() { + // Run the main CPU measurements + timestamp a number of times and capture + // their durations. + constexpr int loops = 128; + TimeDuration durations[loops]; + RunningTimes runningTimes; + TimeStamp before = TimeStamp::Now(); + for (int i = 0; i < loops; ++i) { + AUTO_PROFILER_STATS(GetRunningTimes_MaxRunningTimesReadDuration); + aGetCPURunningTimesFunction(runningTimes); + const TimeStamp after = TimeStamp::Now(); + durations[i] = after - before; + before = after; + } + // Move median duration to the middle. + std::nth_element(&durations[0], &durations[loops / 2], &durations[loops]); + // Use median*8 as cut-off point. + // Typical durations should be around a microsecond, the cut-off should then + // be around 10 microseconds, well below the expected minimum inter-sample + // interval (observed as a few milliseconds), so overall this should keep + // cpu/interval spikes + return durations[loops / 2] * 8; + }(); + + // Record CPU measurements between two timestamps. + RunningTimes runningTimes; + TimeStamp before = TimeStamp::Now(); + aGetCPURunningTimesFunction(runningTimes); + TimeStamp after = TimeStamp::Now(); + const TimeDuration duration = after - before; + + // In most cases, the above should be quick enough. But if not (e.g., because + // of an OS context switch), repeat once: + if (MOZ_UNLIKELY(duration > scMaxRunningTimesReadDuration)) { + AUTO_PROFILER_STATS(GetRunningTimes_REDO); + RunningTimes runningTimes2; + aGetCPURunningTimesFunction(runningTimes2); + TimeStamp after2 = TimeStamp::Now(); + const TimeDuration duration2 = after2 - after; + if (duration2 < duration) { + // We did it faster, use the new results. (But it could still be slower + // than expected, see note below for why it's acceptable.) + // This must stay *after* the CPU measurements. + runningTimes2.SetPostMeasurementTimeStamp(after2); + return runningTimes2; + } + // Otherwise use the initial results, they were slow, but faster than the + // second attempt. + // This means that something bad happened twice in a row on the same thread! + // So trying more times would be unlikely to get much better, and would be + // more expensive than the precision is worth. + // At worst, it means that a spike of activity may be reported in the next + // time slice. But in the end, the cumulative work is conserved, so it + // should still be visible at about the correct time in the graph. + AUTO_PROFILER_STATS(GetRunningTimes_RedoWasWorse); + } + + // This must stay *after* the CPU measurements. + runningTimes.SetPostMeasurementTimeStamp(after); + + return runningTimes; +} + +//////////////////////////////////////////////////////////////////////// +// BEGIN SamplerThread + +// The sampler thread controls sampling and runs whenever the profiler is +// active. It periodically runs through all registered threads, finds those +// that should be sampled, then pauses and samples them. + +class SamplerThread { + public: + // Creates a sampler thread, but doesn't start it. + SamplerThread(PSLockRef aLock, uint32_t aActivityGeneration, + double aIntervalMilliseconds, uint32_t aFeatures); + ~SamplerThread(); + + // This runs on (is!) the sampler thread. + void Run(); + +#if defined(GP_OS_windows) + // This runs on (is!) the thread to spy on unregistered threads. + void RunUnregisteredThreadSpy(); +#endif + + // This runs on the main thread. + void Stop(PSLockRef aLock); + + void AppendPostSamplingCallback(PSLockRef, PostSamplingCallback&& aCallback) { + // We are under lock, so it's safe to just modify the list pointer. + // Also this means the sampler has not started its run yet, so any callback + // added now will be invoked at the end of the next loop; this guarantees + // that the callback will be invoked after at least one full sampling loop. + mPostSamplingCallbackList = MakeUnique<PostSamplingCallbackListItem>( + std::move(mPostSamplingCallbackList), std::move(aCallback)); + } + + private: + void SpyOnUnregisteredThreads(); + + // Item containing a post-sampling callback, and a tail-list of more items. + // Using a linked list means no need to move items when adding more, and + // "stealing" the whole list is one pointer move. + struct PostSamplingCallbackListItem { + UniquePtr<PostSamplingCallbackListItem> mPrev; + PostSamplingCallback mCallback; + + PostSamplingCallbackListItem(UniquePtr<PostSamplingCallbackListItem> aPrev, + PostSamplingCallback&& aCallback) + : mPrev(std::move(aPrev)), mCallback(std::move(aCallback)) {} + }; + + [[nodiscard]] UniquePtr<PostSamplingCallbackListItem> + TakePostSamplingCallbacks(PSLockRef) { + return std::move(mPostSamplingCallbackList); + } + + static void InvokePostSamplingCallbacks( + UniquePtr<PostSamplingCallbackListItem> aCallbacks, + SamplingState aSamplingState) { + if (!aCallbacks) { + return; + } + // We want to drill down to the last element in this list, which is the + // oldest one, so that we invoke them in FIFO order. + // We don't expect many callbacks, so it's safe to recurse. Note that we're + // moving-from the UniquePtr, so the tail will implicitly get destroyed. + InvokePostSamplingCallbacks(std::move(aCallbacks->mPrev), aSamplingState); + // We are going to destroy this item, so we can safely move-from the + // callback before calling it (in case it has an rvalue-ref-qualified call + // operator). + std::move(aCallbacks->mCallback)(aSamplingState); + // It may be tempting for a future maintainer to change aCallbacks into an + // rvalue reference; this will remind them not to do that! + static_assert( + std::is_same_v<decltype(aCallbacks), + UniquePtr<PostSamplingCallbackListItem>>, + "We need to capture the list by-value, to implicitly destroy it"); + } + + // This suspends the calling thread for the given number of microseconds. + // Best effort timing. + void SleepMicro(uint32_t aMicroseconds); + + // The sampler used to suspend and sample threads. + Sampler mSampler; + + // The activity generation, for detecting when the sampler thread must stop. + const uint32_t mActivityGeneration; + + // The interval between samples, measured in microseconds. + const int mIntervalMicroseconds; + + // The OS-specific handle for the sampler thread. +#if defined(GP_OS_windows) + HANDLE mThread; + HANDLE mUnregisteredThreadSpyThread = nullptr; + enum class SpyingState { + NoSpying, + Spy_Initializing, + // Spy is waiting for SamplerToSpy_Start or MainToSpy_Shutdown. + Spy_Waiting, + // Sampler requests spy to start working. May be pre-empted by + // MainToSpy_Shutdown. + SamplerToSpy_Start, + // Spy is currently working, cannot be interrupted, only the spy is allowed + // to change the state again. + Spy_Working, + // Main control requests spy to shut down. + MainToSpy_Shutdown, + // Spy notified main control that it's out of the loop, about to exit. + SpyToMain_ShuttingDown + }; + SpyingState mSpyingState = SpyingState::NoSpying; + // The sampler will increment this while the spy is working, then while the + // spy is waiting the sampler will decrement it until <=0 before starting the + // spy. This will ensure that the work doesn't take more than 50% of a CPU + // core. + int mDelaySpyStart = 0; + Monitor mSpyingStateMonitor MOZ_UNANNOTATED{ + "SamplerThread::mSpyingStateMonitor"}; +#elif defined(GP_OS_darwin) || defined(GP_OS_linux) || \ + defined(GP_OS_android) || defined(GP_OS_freebsd) + pthread_t mThread; +#endif + + // Post-sampling callbacks are kept in a simple linked list, which will be + // stolen by the sampler thread at the end of its next run. + UniquePtr<PostSamplingCallbackListItem> mPostSamplingCallbackList; + +#if defined(GP_OS_windows) + bool mNoTimerResolutionChange = true; +#endif + + struct SpiedThread { + base::ProcessId mThreadId; + nsCString mName; + uint64_t mCPUTimeNs; + + SpiedThread(base::ProcessId aThreadId, const nsACString& aName, + uint64_t aCPUTimeNs) + : mThreadId(aThreadId), mName(aName), mCPUTimeNs(aCPUTimeNs) {} + + // Comparisons with just a thread id, for easy searching in an array. + friend bool operator==(const SpiedThread& aSpiedThread, + base::ProcessId aThreadId) { + return aSpiedThread.mThreadId == aThreadId; + } + friend bool operator==(base::ProcessId aThreadId, + const SpiedThread& aSpiedThread) { + return aThreadId == aSpiedThread.mThreadId; + } + }; + + // Time at which mSpiedThreads was previously updated. Null before 1st update. + TimeStamp mLastSpying; + // Unregistered threads that have been found, and are being spied on. + using SpiedThreads = AutoTArray<SpiedThread, 128>; + SpiedThreads mSpiedThreads; + + SamplerThread(const SamplerThread&) = delete; + void operator=(const SamplerThread&) = delete; +}; + +namespace geckoprofiler::markers { +struct CPUSpeedMarker { + static constexpr Span<const char> MarkerTypeName() { + return MakeStringSpan("CPUSpeed"); + } + static void StreamJSONMarkerData(baseprofiler::SpliceableJSONWriter& aWriter, + uint32_t aCPUSpeedMHz) { + aWriter.DoubleProperty("speed", double(aCPUSpeedMHz) / 1000); + } + static MarkerSchema MarkerTypeDisplay() { + using MS = MarkerSchema; + MS schema{MS::Location::MarkerChart, MS::Location::MarkerTable}; + schema.SetTableLabel("{marker.name} Speed = {marker.data.speed}GHz"); + schema.AddKeyLabelFormat("speed", "CPU Speed (GHz)", MS::Format::String); + schema.AddChartColor("speed", MS::GraphType::Bar, MS::GraphColor::Ink); + return schema; + } +}; +} // namespace geckoprofiler::markers + +// [[nodiscard]] static +bool ActivePS::AppendPostSamplingCallback(PSLockRef aLock, + PostSamplingCallback&& aCallback) { + if (!sInstance || !sInstance->mSamplerThread) { + return false; + } + sInstance->mSamplerThread->AppendPostSamplingCallback(aLock, + std::move(aCallback)); + return true; +} + +// This function is required because we need to create a SamplerThread within +// ActivePS's constructor, but SamplerThread is defined after ActivePS. It +// could probably be removed by moving some code around. +static SamplerThread* NewSamplerThread(PSLockRef aLock, uint32_t aGeneration, + double aInterval, uint32_t aFeatures) { + return new SamplerThread(aLock, aGeneration, aInterval, aFeatures); +} + +// This function is the sampler thread. This implementation is used for all +// targets. +void SamplerThread::Run() { + NS_SetCurrentThreadName("SamplerThread"); + + // Features won't change during this SamplerThread's lifetime, so we can read + // them once and store them locally. + const uint32_t features = []() -> uint32_t { + PSAutoLock lock; + if (!ActivePS::Exists(lock)) { + // If there is no active profiler, it doesn't matter what we return, + // because this thread will exit before any feature is used. + return 0; + } + return ActivePS::Features(lock); + }(); + + // Not *no*-stack-sampling means we do want stack sampling. + const bool stackSampling = !ProfilerFeature::HasNoStackSampling(features); + + const bool cpuUtilization = ProfilerFeature::HasCPUUtilization(features); + + // Use local ProfileBuffer and underlying buffer to capture the stack. + // (This is to avoid touching the core buffer lock while a thread is + // suspended, because that thread could be working with the core buffer as + // well. + mozilla::ProfileBufferChunkManagerSingle localChunkManager( + ProfileBufferChunkManager::scExpectedMaximumStackSize); + ProfileChunkedBuffer localBuffer( + ProfileChunkedBuffer::ThreadSafety::WithoutMutex, localChunkManager); + ProfileBuffer localProfileBuffer(localBuffer); + + // Will be kept between collections, to know what each collection does. + auto previousState = localBuffer.GetState(); + + // This will be filled at every loop, to be used by the next loop to compute + // the CPU utilization between samples. + RunningTimes processRunningTimes; + + // This will be set inside the loop, from inside the lock scope, to capture + // all callbacks added before that, but none after the lock is released. + UniquePtr<PostSamplingCallbackListItem> postSamplingCallbacks; + // This will be set inside the loop, before invoking callbacks outside. + SamplingState samplingState{}; + + const TimeDuration sampleInterval = + TimeDuration::FromMicroseconds(mIntervalMicroseconds); + const uint32_t minimumIntervalSleepUs = + static_cast<uint32_t>(mIntervalMicroseconds / 4); + + // This is the scheduled time at which each sampling loop should start. + // It will determine the ideal next sampling start by adding the expected + // interval, unless when sampling runs late -- See end of while() loop. + TimeStamp scheduledSampleStart = TimeStamp::Now(); + +#if defined(HAVE_CPU_FREQ_SUPPORT) + // Used to collect CPU core frequencies, if the cpufreq feature is on. + Vector<uint32_t> CPUSpeeds; + + if (XRE_IsParentProcess() && ProfilerFeature::HasCPUFrequency(features) && + CPUSpeeds.resize(GetNumberOfProcessors())) { + { + PSAutoLock lock; + if (ProfilerCPUFreq* cpuFreq = ActivePS::MaybeCPUFreq(lock); cpuFreq) { + cpuFreq->Sample(); + for (size_t i = 0; i < CPUSpeeds.length(); ++i) { + CPUSpeeds[i] = cpuFreq->GetCPUSpeedMHz(i); + } + } + } + TimeStamp now = TimeStamp::Now(); + for (size_t i = 0; i < CPUSpeeds.length(); ++i) { + nsAutoCString name; + name.AssignLiteral("CPU "); + name.AppendInt(i); + + PROFILER_MARKER(name, OTHER, + MarkerOptions(MarkerThreadId::MainThread(), + MarkerTiming::IntervalStart(now)), + CPUSpeedMarker, CPUSpeeds[i]); + } + } +#endif + + while (true) { + const TimeStamp sampleStart = TimeStamp::Now(); + + // This scope is for |lock|. It ends before we sleep below. + { + // There should be no local callbacks left from a previous loop. + MOZ_ASSERT(!postSamplingCallbacks); + + PSAutoLock lock; + TimeStamp lockAcquired = TimeStamp::Now(); + + // Move all the post-sampling callbacks locally, so that new ones cannot + // sneak in between the end of the lock scope and the invocation after it. + postSamplingCallbacks = TakePostSamplingCallbacks(lock); + + if (!ActivePS::Exists(lock)) { + // Exit the `while` loop, including the lock scope, before invoking + // callbacks and returning. + samplingState = SamplingState::JustStopped; + break; + } + + // At this point profiler_stop() might have been called, and + // profiler_start() might have been called on another thread. If this + // happens the generation won't match. + if (ActivePS::Generation(lock) != mActivityGeneration) { + samplingState = SamplingState::JustStopped; + // Exit the `while` loop, including the lock scope, before invoking + // callbacks and returning. + break; + } + + ActivePS::ClearExpiredExitProfiles(lock); + + TimeStamp expiredMarkersCleaned = TimeStamp::Now(); + + if (int(gSkipSampling) <= 0 && !ActivePS::IsSamplingPaused(lock)) { + double sampleStartDeltaMs = + (sampleStart - CorePS::ProcessStartTime()).ToMilliseconds(); + ProfileBuffer& buffer = ActivePS::Buffer(lock); + + // Before sampling counters, update the process CPU counter if active. + if (ActivePS::ProcessCPUCounter* processCPUCounter = + ActivePS::MaybeProcessCPUCounter(lock); + processCPUCounter) { + RunningTimes processRunningTimesDiff = + GetProcessRunningTimesDiff(lock, processRunningTimes); + Maybe<uint64_t> cpu = processRunningTimesDiff.GetJsonThreadCPUDelta(); + if (cpu) { + processCPUCounter->Add(static_cast<int64_t>(*cpu)); + } + } + +#if defined(HAVE_CPU_FREQ_SUPPORT) + if (XRE_IsParentProcess() && CPUSpeeds.length() > 0) { + unsigned newSpeed[CPUSpeeds.length()]; + if (ProfilerCPUFreq* cpuFreq = ActivePS::MaybeCPUFreq(lock); + cpuFreq) { + cpuFreq->Sample(); + for (size_t i = 0; i < CPUSpeeds.length(); ++i) { + newSpeed[i] = cpuFreq->GetCPUSpeedMHz(i); + } + } + TimeStamp now = TimeStamp::Now(); + for (size_t i = 0; i < CPUSpeeds.length(); ++i) { + if (newSpeed[i] == CPUSpeeds[i]) { + continue; + } + + nsAutoCString name; + name.AssignLiteral("CPU "); + name.AppendInt(i); + + PROFILER_MARKER_UNTYPED( + name, OTHER, + MarkerOptions(MarkerThreadId::MainThread(), + MarkerTiming::IntervalEnd(now))); + PROFILER_MARKER(name, OTHER, + MarkerOptions(MarkerThreadId::MainThread(), + MarkerTiming::IntervalStart(now)), + CPUSpeedMarker, newSpeed[i]); + + CPUSpeeds[i] = newSpeed[i]; + } + } +#endif + + if (PowerCounters* powerCounters = ActivePS::MaybePowerCounters(lock); + powerCounters) { + powerCounters->Sample(); + } + + // handle per-process generic counters + double counterSampleStartDeltaMs = + (TimeStamp::Now() - CorePS::ProcessStartTime()).ToMilliseconds(); + const Vector<BaseProfilerCount*>& counters = CorePS::Counters(lock); + for (auto& counter : counters) { + if (auto sample = counter->Sample(); sample.isSampleNew) { + // create Buffer entries for each counter + buffer.AddEntry(ProfileBufferEntry::CounterId(counter)); + buffer.AddEntry( + ProfileBufferEntry::Time(counterSampleStartDeltaMs)); +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + if (ActivePS::IsMemoryCounter(counter)) { + // For the memory counter, substract the size of our buffer to + // avoid giving the misleading impression that the memory use + // keeps on growing when it's just the profiler session that's + // using a larger buffer as it gets longer. + sample.count -= static_cast<int64_t>( + ActivePS::ControlledChunkManager(lock).TotalSize()); + } +#endif + buffer.AddEntry(ProfileBufferEntry::Count(sample.count)); + if (sample.number) { + buffer.AddEntry(ProfileBufferEntry::Number(sample.number)); + } + } + } + TimeStamp countersSampled = TimeStamp::Now(); + + if (stackSampling || cpuUtilization) { + samplingState = SamplingState::SamplingCompleted; + + // Prevent threads from ending (or starting) and allow access to all + // OffThreadRef's. + ThreadRegistry::LockedRegistry lockedRegistry; + + for (ThreadRegistry::OffThreadRef offThreadRef : lockedRegistry) { + ThreadRegistration::UnlockedRWForLockedProfiler& + unlockedThreadData = + offThreadRef.UnlockedRWForLockedProfilerRef(); + ProfiledThreadData* profiledThreadData = + unlockedThreadData.GetProfiledThreadData(lock); + if (!profiledThreadData) { + // This thread is not being profiled, continue with the next one. + continue; + } + + const ThreadProfilingFeatures whatToProfile = + unlockedThreadData.ProfilingFeatures(); + const bool threadCPUUtilization = + cpuUtilization && + DoFeaturesIntersect(whatToProfile, + ThreadProfilingFeatures::CPUUtilization); + const bool threadStackSampling = + stackSampling && + DoFeaturesIntersect(whatToProfile, + ThreadProfilingFeatures::Sampling); + if (!threadCPUUtilization && !threadStackSampling) { + // Nothing to profile on this thread, continue with the next one. + continue; + } + + const ProfilerThreadId threadId = + unlockedThreadData.Info().ThreadId(); + + const RunningTimes runningTimesDiff = [&]() { + if (!threadCPUUtilization) { + // If we don't need CPU measurements, we only need a timestamp. + return RunningTimes(TimeStamp::Now()); + } + return GetThreadRunningTimesDiff(lock, unlockedThreadData); + }(); + + const TimeStamp& now = runningTimesDiff.PostMeasurementTimeStamp(); + double threadSampleDeltaMs = + (now - CorePS::ProcessStartTime()).ToMilliseconds(); + + // If the thread is asleep and has been sampled before in the same + // sleep episode, or otherwise(*) if there was zero CPU activity + // since the previous sampling, find and copy the previous sample, + // as that's cheaper than taking a new sample. + // (*) Tech note: The asleep check is done first and always, because + // it is more reliable, and knows if it's the first asleep + // sample, which cannot be duplicated; if the test was the other + // way around, it could find zero CPU and then short-circuit + // that state-changing second-asleep-check operation, which + // could result in an unneeded sample. + // However we're using current running times (instead of copying the + // old ones) because some work could have happened. + if (threadStackSampling && + (unlockedThreadData.CanDuplicateLastSampleDueToSleep() || + runningTimesDiff.GetThreadCPUDelta() == Some(uint64_t(0)))) { + const bool dup_ok = ActivePS::Buffer(lock).DuplicateLastSample( + threadId, threadSampleDeltaMs, + profiledThreadData->LastSample(), runningTimesDiff); + if (dup_ok) { + continue; + } + } + + AUTO_PROFILER_STATS(gecko_SamplerThread_Run_DoPeriodicSample); + + // Record the global profiler buffer's range start now, before + // adding the first entry for this thread's sample. + const uint64_t bufferRangeStart = buffer.BufferRangeStart(); + + // Add the thread ID now, so we know its position in the main + // buffer, which is used by some JS data. + // (DoPeriodicSample only knows about the temporary local buffer.) + const uint64_t samplePos = buffer.AddThreadIdEntry(threadId); + profiledThreadData->LastSample() = Some(samplePos); + + // Also add the time, so it's always there after the thread ID, as + // expected by the parser. (Other stack data is optional.) + buffer.AddEntry(ProfileBufferEntry::TimeBeforeCompactStack( + threadSampleDeltaMs)); + + Maybe<double> unresponsiveDuration_ms; + + // If we have RunningTimes data, store it before the CompactStack. + // Note: It is not stored inside the CompactStack so that it doesn't + // get incorrectly duplicated when the thread is sleeping. + if (!runningTimesDiff.IsEmpty()) { + profiler_get_core_buffer().PutObjects( + ProfileBufferEntry::Kind::RunningTimes, runningTimesDiff); + } + + if (threadStackSampling) { + ThreadRegistry::OffThreadRef::RWFromAnyThreadWithLock + lockedThreadData = offThreadRef.GetLockedRWFromAnyThread(); + // Suspend the thread and collect its stack data in the local + // buffer. + mSampler.SuspendAndSampleAndResumeThread( + lock, lockedThreadData.DataCRef(), now, + [&](const Registers& aRegs, const TimeStamp& aNow) { + DoPeriodicSample(lock, lockedThreadData.DataCRef(), aRegs, + samplePos, bufferRangeStart, + localProfileBuffer); + + // For "eventDelay", we want the input delay - but if + // there are no events in the input queue (or even if there + // are), we're interested in how long the delay *would* be + // for an input event now, which would be the time to finish + // the current event + the delay caused by any events + // already in the input queue (plus any High priority + // events). Events at lower priorities (in a + // PrioritizedEventQueue) than Input count for input delay + // only for the duration that they're running, since when + // they finish, any queued input event would run. + // + // Unless we record the time state of all events and queue + // states at all times, this is hard to precisely calculate, + // but we can approximate it well in post-processing with + // RunningEventDelay and RunningEventStart. + // + // RunningEventDelay is the time duration the event was + // queued before starting execution. RunningEventStart is + // the time the event started. (Note: since we care about + // Input event delays on MainThread, for + // PrioritizedEventQueues we return 0 for RunningEventDelay + // if the currently running event has a lower priority than + // Input (since Input events won't queue behind them). + // + // To directly measure this we would need to record the time + // at which the newest event currently in each queue at time + // X (the sample time) finishes running. This of course + // would require looking into the future, or recording all + // this state and then post-processing it later. If we were + // to trace every event start and end we could do this, but + // it would have significant overhead to do so (and buffer + // usage). From a recording of RunningEventDelays and + // RunningEventStarts we can infer the actual delay: + // + // clang-format off + // Event queue: <tail> D : C : B : A <head> + // Time inserted (ms): 40 : 20 : 10 : 0 + // Run Time (ms): 30 : 100 : 40 : 30 + // + // 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 + // [A||||||||||||] + // ----------[B|||||||||||||||||] + // -------------------------[C|||||||||||||||||||||||||||||||||||||||||||||||] + // -----------------------------------------------------------------[D|||||||||...] + // + // Calculate the delay of a new event added at time t: (run every sample) + // TimeSinceRunningEventBlockedInputEvents = RunningEventDelay + (now - RunningEventStart); + // effective_submission = now - TimeSinceRunningEventBlockedInputEvents; + // delta = (now - last_sample_time); + // last_sample_time = now; + // for (t=effective_submission to now) { + // delay[t] += delta; + // } + // + // Can be reduced in overhead by: + // TimeSinceRunningEventBlockedInputEvents = RunningEventDelay + (now - RunningEventStart); + // effective_submission = now - TimeSinceRunningEventBlockedInputEvents; + // if (effective_submission != last_submission) { + // delta = (now - last_submision); + // // this loop should be made to match each sample point in the range + // // intead of assuming 1ms sampling as this pseudocode does + // for (t=last_submission to effective_submission-1) { + // delay[t] += delta; + // delta -= 1; // assumes 1ms; adjust as needed to match for() + // } + // last_submission = effective_submission; + // } + // + // Time Head of queue Running Event RunningEventDelay Delay of Effective Started Calc (submission->now add 10ms) Final + // hypothetical Submission Running @ result + // event E + // 0 Empty A 0 30 0 0 @0=10 30 + // 10 B A 0 60 0 0 @0=20, @10=10 60 + // 20 B A 0 150 0 0 @0=30, @10=20, @20=10 150 + // 30 C B 20 140 10 30 @10=20, @20=10, @30=0 140 + // 40 C B 20 160 @10=30, @20=20... 160 + // 50 C B 20 150 150 + // 60 C B 20 140 @10=50, @20=40... 140 + // 70 D C 50 130 20 70 @20=50, @30=40... 130 + // ... + // 160 D C 50 40 @20=140, @30=130... 40 + // 170 <empty> D 140 30 40 @40=140, @50=130... (rounding) 30 + // 180 <empty> D 140 20 40 @40=150 20 + // 190 <empty> D 140 10 40 @40=160 10 + // 200 <empty> <empty> 0 0 NA 0 + // + // Function Delay(t) = the time between t and the time at which a hypothetical + // event e would start executing, if e was enqueued at time t. + // + // Delay(-1) = 0 // Before A was enqueued. No wait time, can start running + // // instantly. + // Delay(0) = 30 // The hypothetical event e got enqueued just after A got + // // enqueued. It can start running at 30, when A is done. + // Delay(5) = 25 + // Delay(10) = 60 // Can start running at 70, after both A and B are done. + // Delay(19) = 51 + // Delay(20) = 150 // Can start running at 170, after A, B & C. + // Delay(25) = 145 + // Delay(30) = 170 // Can start running at 200, after A, B, C & D. + // Delay(120) = 80 + // Delay(200) = 0 // (assuming nothing was enqueued after D) + // + // For every event that gets enqueued, the Delay time will go up by the + // event's running time at the time at which the event is enqueued. + // The Delay function will be a sawtooth of the following shape: + // + // |\ |... + // | \ | + // |\ | \ | + // | \ | \ | + // |\ | \ | \ | + // |\ | \| \| \ | + // | \| \ | + // _| \____| + // + // + // A more complex example with a PrioritizedEventQueue: + // + // Event queue: <tail> D : C : B : A <head> + // Time inserted (ms): 40 : 20 : 10 : 0 + // Run Time (ms): 30 : 100 : 40 : 30 + // Priority: Input: Norm: Norm: Norm + // + // 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 + // [A||||||||||||] + // ----------[B|||||||||||||||||] + // ----------------------------------------[C|||||||||||||||||||||||||||||||||||||||||||||||] + // ---------------[D||||||||||||] + // + // + // Time Head of queue Running Event RunningEventDelay Delay of Effective Started Calc (submission->now add 10ms) Final + // hypothetical Submission Running @ result + // event + // 0 Empty A 0 30 0 0 @0=10 30 + // 10 B A 0 20 0 0 @0=20, @10=10 20 + // 20 B A 0 10 0 0 @0=30, @10=20, @20=10 10 + // 30 C B 0 40 30 30 @30=10 40 + // 40 C B 0 60 30 @40=10, @30=20 60 + // 50 C B 0 50 30 @50=10, @40=20, @30=30 50 + // 60 C B 0 40 30 @60=10, @50=20, @40=30, @30=40 40 + // 70 C D 30 30 40 70 @60=20, @50=30, @40=40 30 + // 80 C D 30 20 40 70 ...@50=40, @40=50 20 + // 90 C D 30 10 40 70 ...@60=40, @50=50, @40=60 10 + // 100 <empty> C 0 100 100 100 @100=10 100 + // 110 <empty> C 0 90 100 100 @110=10, @100=20 90 + + // + // For PrioritizedEventQueue, the definition of the Delay(t) function is adjusted: the hypothetical event e has Input priority. + // Delay(-1) = 0 // Before A was enqueued. No wait time, can start running + // // instantly. + // Delay(0) = 30 // The hypothetical input event e got enqueued just after A got + // // enqueued. It can start running at 30, when A is done. + // Delay(5) = 25 + // Delay(10) = 20 + // Delay(25) = 5 // B has been queued, but e does not need to wait for B because e has Input priority and B does not. + // // So e can start running at 30, when A is done. + // Delay(30) = 40 // Can start running at 70, after B is done. + // Delay(40) = 60 // Can start at 100, after B and D are done (D is Input Priority) + // Delay(80) = 20 + // Delay(100) = 100 // Wait for C to finish + + // clang-format on + // + // Alternatively we could insert (recycled instead of + // allocated/freed) input events at every sample period + // (1ms...), and use them to back-calculate the delay. This + // might also be somewhat expensive, and would require + // guessing at the maximum delay, which would likely be in + // the seconds, and so you'd need 1000's of pre-allocated + // events per queue per thread - so there would be a memory + // impact as well. + + TimeDuration currentEventDelay; + TimeDuration currentEventRunning; + lockedThreadData->GetRunningEventDelay( + aNow, currentEventDelay, currentEventRunning); + + // Note: eventDelay is a different definition of + // responsiveness than the 16ms event injection. + + // Don't suppress 0's for now; that can be a future + // optimization. We probably want one zero to be stored + // before we start suppressing, which would be more + // complex. + unresponsiveDuration_ms = + Some(currentEventDelay.ToMilliseconds() + + currentEventRunning.ToMilliseconds()); + }); + + if (cpuUtilization) { + // Suspending the thread for sampling could have added some + // running time to it, discard any since the call to + // GetThreadRunningTimesDiff above. + DiscardSuspendedThreadRunningTimes(lock, unlockedThreadData); + } + + // If we got eventDelay data, store it before the CompactStack. + // Note: It is not stored inside the CompactStack so that it + // doesn't get incorrectly duplicated when the thread is sleeping. + if (unresponsiveDuration_ms.isSome()) { + profiler_get_core_buffer().PutObjects( + ProfileBufferEntry::Kind::UnresponsiveDurationMs, + *unresponsiveDuration_ms); + } + } + + // There *must* be a CompactStack after a TimeBeforeCompactStack; + // but note that other entries may have been concurrently inserted + // between the TimeBeforeCompactStack above and now. If the captured + // sample from `DoPeriodicSample` is complete, copy it into the + // global buffer, otherwise add an empty one to satisfy the parser + // that expects one. + auto state = localBuffer.GetState(); + if (NS_WARN_IF(state.mFailedPutBytes != + previousState.mFailedPutBytes)) { + LOG("Stack sample too big for local storage, failed to store %u " + "bytes", + unsigned(state.mFailedPutBytes - + previousState.mFailedPutBytes)); + // There *must* be a CompactStack after a TimeBeforeCompactStack, + // even an empty one. + profiler_get_core_buffer().PutObjects( + ProfileBufferEntry::Kind::CompactStack, + UniquePtr<ProfileChunkedBuffer>(nullptr)); + } else if (state.mRangeEnd - previousState.mRangeEnd >= + *profiler_get_core_buffer().BufferLength()) { + LOG("Stack sample too big for profiler storage, needed %u bytes", + unsigned(state.mRangeEnd - previousState.mRangeEnd)); + // There *must* be a CompactStack after a TimeBeforeCompactStack, + // even an empty one. + profiler_get_core_buffer().PutObjects( + ProfileBufferEntry::Kind::CompactStack, + UniquePtr<ProfileChunkedBuffer>(nullptr)); + } else { + profiler_get_core_buffer().PutObjects( + ProfileBufferEntry::Kind::CompactStack, localBuffer); + } + + // Clean up for the next run. + localBuffer.Clear(); + previousState = localBuffer.GetState(); + } + } else { + samplingState = SamplingState::NoStackSamplingCompleted; + } + +#if defined(USE_LUL_STACKWALK) + // The LUL unwind object accumulates frame statistics. Periodically we + // should poke it to give it a chance to print those statistics. This + // involves doing I/O (fprintf, __android_log_print, etc.) and so + // can't safely be done from the critical section inside + // SuspendAndSampleAndResumeThread, which is why it is done here. + lul::LUL* lul = CorePS::Lul(); + if (lul) { + lul->MaybeShowStats(); + } +#endif + TimeStamp threadsSampled = TimeStamp::Now(); + + { + AUTO_PROFILER_STATS(Sampler_FulfillChunkRequests); + ActivePS::FulfillChunkRequests(lock); + } + + buffer.CollectOverheadStats(sampleStartDeltaMs, + lockAcquired - sampleStart, + expiredMarkersCleaned - lockAcquired, + countersSampled - expiredMarkersCleaned, + threadsSampled - countersSampled); + } else { + samplingState = SamplingState::SamplingPaused; + } + } + // gPSMutex is not held after this point. + + // Invoke end-of-sampling callbacks outside of the locked scope. + InvokePostSamplingCallbacks(std::move(postSamplingCallbacks), + samplingState); + + ProfilerChild::ProcessPendingUpdate(); + + if (ProfilerFeature::HasUnregisteredThreads(features)) { +#if defined(GP_OS_windows) + { + MonitorAutoLock spyingStateLock{mSpyingStateMonitor}; + switch (mSpyingState) { + case SpyingState::SamplerToSpy_Start: + case SpyingState::Spy_Working: + // If the spy is working (or about to work), record this loop + // iteration to delay the next start. + ++mDelaySpyStart; + break; + case SpyingState::Spy_Waiting: + // The Spy is idle, waiting for instructions. Should we delay? + if (--mDelaySpyStart <= 0) { + mDelaySpyStart = 0; + mSpyingState = SpyingState::SamplerToSpy_Start; + mSpyingStateMonitor.NotifyAll(); + } + break; + default: + // Otherwise the spy should be initializing or shutting down. + MOZ_ASSERT(mSpyingState == SpyingState::Spy_Initializing || + mSpyingState == SpyingState::MainToSpy_Shutdown || + mSpyingState == SpyingState::SpyToMain_ShuttingDown); + break; + } + } +#else + // On non-Windows platforms, this is fast enough to run in this thread, + // each sampling loop. + SpyOnUnregisteredThreads(); +#endif + } + + // We expect the next sampling loop to start `sampleInterval` after this + // loop here was scheduled to start. + scheduledSampleStart += sampleInterval; + + // Try to sleep until we reach that next scheduled time. + const TimeStamp beforeSleep = TimeStamp::Now(); + if (scheduledSampleStart >= beforeSleep) { + // There is still time before the next scheduled sample time. + const uint32_t sleepTimeUs = static_cast<uint32_t>( + (scheduledSampleStart - beforeSleep).ToMicroseconds()); + if (sleepTimeUs >= minimumIntervalSleepUs) { + SleepMicro(sleepTimeUs); + } else { + // If we're too close to that time, sleep the minimum amount of time. + // Note that the next scheduled start is not shifted, so at the end of + // the next loop, sleep may again be adjusted to get closer to schedule. + SleepMicro(minimumIntervalSleepUs); + } + } else { + // This sampling loop ended after the next sampling should have started! + // There is little point to try and keep up to schedule now, it would + // require more work, while it's likely we're late because the system is + // already busy. Try and restart a normal schedule from now. + scheduledSampleStart = beforeSleep + sampleInterval; + SleepMicro(static_cast<uint32_t>(sampleInterval.ToMicroseconds())); + } + } + + // End of `while` loop. We can only be here from a `break` inside the loop. + InvokePostSamplingCallbacks(std::move(postSamplingCallbacks), samplingState); +} + +namespace geckoprofiler::markers { + +struct UnregisteredThreadLifetimeMarker { + static constexpr Span<const char> MarkerTypeName() { + return MakeStringSpan("UnregisteredThreadLifetime"); + } + static void StreamJSONMarkerData(baseprofiler::SpliceableJSONWriter& aWriter, + base::ProcessId aThreadId, + const ProfilerString8View& aName, + const ProfilerString8View& aEndEvent) { + aWriter.IntProperty("Thread Id", aThreadId); + aWriter.StringProperty("Thread Name", aName.Length() != 0 + ? aName.AsSpan() + : MakeStringSpan("~Unnamed~")); + if (aEndEvent.Length() != 0) { + aWriter.StringProperty("End Event", aEndEvent); + } + } + static MarkerSchema MarkerTypeDisplay() { + using MS = MarkerSchema; + MS schema{MS::Location::MarkerChart, MS::Location::MarkerTable}; + schema.AddKeyFormatSearchable("Thread Id", MS::Format::Integer, + MS::Searchable::Searchable); + schema.AddKeyFormatSearchable("Thread Name", MS::Format::String, + MS::Searchable::Searchable); + schema.AddKeyFormat("End Event", MS::Format::String); + schema.AddStaticLabelValue( + "Note", + "Start and end are approximate, based on first and last appearances."); + schema.SetChartLabel( + "{marker.data.Thread Name} (tid {marker.data.Thread Id})"); + schema.SetTableLabel("{marker.name} lifetime"); + return schema; + } +}; + +struct UnregisteredThreadCPUMarker { + static constexpr Span<const char> MarkerTypeName() { + return MakeStringSpan("UnregisteredThreadCPU"); + } + static void StreamJSONMarkerData(baseprofiler::SpliceableJSONWriter& aWriter, + base::ProcessId aThreadId, + int64_t aCPUDiffNs, const TimeStamp& aStart, + const TimeStamp& aEnd) { + aWriter.IntProperty("Thread Id", aThreadId); + aWriter.IntProperty("CPU Time", aCPUDiffNs); + aWriter.DoubleProperty( + "CPU Utilization", + double(aCPUDiffNs) / ((aEnd - aStart).ToMicroseconds() * 1000.0)); + } + static MarkerSchema MarkerTypeDisplay() { + using MS = MarkerSchema; + MS schema{MS::Location::MarkerChart, MS::Location::MarkerTable}; + schema.AddKeyFormatSearchable("Thread Id", MS::Format::Integer, + MS::Searchable::Searchable); + schema.AddKeyFormat("CPU Time", MS::Format::Nanoseconds); + schema.AddKeyFormat("CPU Utilization", MS::Format::Percentage); + schema.SetChartLabel("{marker.data.CPU Utilization}"); + schema.SetTableLabel( + "{marker.name} - Activity: {marker.data.CPU Utilization}"); + return schema; + } +}; + +} // namespace geckoprofiler::markers + +static bool IsThreadIdRegistered(ProfilerThreadId aThreadId) { + ThreadRegistry::LockedRegistry lockedRegistry; + const auto registryEnd = lockedRegistry.end(); + return std::find_if( + lockedRegistry.begin(), registryEnd, + [aThreadId](const ThreadRegistry::OffThreadRef& aOffThreadRef) { + return aOffThreadRef.UnlockedConstReaderCRef() + .Info() + .ThreadId() == aThreadId; + }) != registryEnd; +} + +static nsAutoCString MakeThreadInfoMarkerName(base::ProcessId aThreadId, + const nsACString& aName) { + nsAutoCString markerName{"tid "}; + markerName.AppendInt(int64_t(aThreadId)); + if (!aName.IsEmpty()) { + markerName.AppendLiteral(" "); + markerName.Append(aName); + } + return markerName; +} + +void SamplerThread::SpyOnUnregisteredThreads() { + const TimeStamp unregisteredThreadSearchStart = TimeStamp::Now(); + + const base::ProcessId currentProcessId = + base::ProcessId(profiler_current_process_id().ToNumber()); + nsTArray<ProcInfoRequest> request(1); + request.EmplaceBack( + /* aPid = */ currentProcessId, + /* aProcessType = */ ProcType::Unknown, + /* aOrigin = */ ""_ns, + /* aWindowInfo = */ nsTArray<WindowInfo>{}, + /* aUtilityInfo = */ nsTArray<UtilityInfo>{}, + /* aChild = */ 0 +#ifdef XP_MACOSX + , + /* aChildTask = */ MACH_PORT_NULL +#endif // XP_MACOSX + ); + + const ProcInfoPromise::ResolveOrRejectValue procInfoOrError = + GetProcInfoSync(std::move(request)); + + if (!procInfoOrError.IsResolve()) { + PROFILER_MARKER_TEXT("Failed unregistered thread search", PROFILER, + MarkerOptions(MarkerThreadId::MainThread(), + MarkerTiming::IntervalUntilNowFrom( + unregisteredThreadSearchStart)), + "Could not retrieve any process information"); + return; + } + + const auto& procInfoHashMap = procInfoOrError.ResolveValue(); + // Expecting the requested (current) process information to be present in the + // hashmap. + const auto& procInfoPtr = + procInfoHashMap.readonlyThreadsafeLookup(currentProcessId); + if (!procInfoPtr) { + PROFILER_MARKER_TEXT("Failed unregistered thread search", PROFILER, + MarkerOptions(MarkerThreadId::MainThread(), + MarkerTiming::IntervalUntilNowFrom( + unregisteredThreadSearchStart)), + "Could not retrieve information about this process"); + return; + } + + // Record the time spent so far, which is OS-bound... + PROFILER_MARKER_TEXT("Unregistered thread search", PROFILER, + MarkerOptions(MarkerThreadId::MainThread(), + MarkerTiming::IntervalUntilNowFrom( + unregisteredThreadSearchStart)), + "Work to discover threads"); + + // ... and record the time needed to process the data, which we can control. + AUTO_PROFILER_MARKER_TEXT( + "Unregistered thread search", PROFILER, + MarkerOptions(MarkerThreadId::MainThread()), + "Work to process discovered threads and record unregistered ones"_ns); + + const Span<const mozilla::ThreadInfo> threads = procInfoPtr->value().threads; + + // mLastSpying timestamp should be null only at the beginning of a session, + // when mSpiedThreads is still empty. + MOZ_ASSERT_IF(mLastSpying.IsNull(), mSpiedThreads.IsEmpty()); + + const TimeStamp previousSpying = std::exchange(mLastSpying, TimeStamp::Now()); + + // Find threads that were spied on but are not present anymore. + const auto threadsBegin = threads.begin(); + const auto threadsEnd = threads.end(); + for (size_t spiedThreadIndexPlus1 = mSpiedThreads.Length(); + spiedThreadIndexPlus1 != 0; --spiedThreadIndexPlus1) { + const SpiedThread& spiedThread = mSpiedThreads[spiedThreadIndexPlus1 - 1]; + if (std::find_if(threadsBegin, threadsEnd, + [spiedTid = spiedThread.mThreadId]( + const mozilla::ThreadInfo& aThreadInfo) { + return aThreadInfo.tid == spiedTid; + }) == threadsEnd) { + // This spied thread is gone. + PROFILER_MARKER( + MakeThreadInfoMarkerName(spiedThread.mThreadId, spiedThread.mName), + PROFILER, + MarkerOptions( + MarkerThreadId::MainThread(), + // Place the end between this update and the previous one. + MarkerTiming::IntervalEnd(previousSpying + + (mLastSpying - previousSpying) / + int64_t(2))), + UnregisteredThreadLifetimeMarker, spiedThread.mThreadId, + spiedThread.mName, "Thread disappeared"); + + // Don't spy on it anymore, assuming it won't come back. + mSpiedThreads.RemoveElementAt(spiedThreadIndexPlus1 - 1); + } + } + + for (const mozilla::ThreadInfo& threadInfo : threads) { + // Index of this encountered thread in mSpiedThreads, or NoIndex. + size_t spiedThreadIndex = mSpiedThreads.IndexOf(threadInfo.tid); + if (IsThreadIdRegistered(ProfilerThreadId::FromNumber(threadInfo.tid))) { + // This thread id is already officially registered. + if (spiedThreadIndex != SpiedThreads::NoIndex) { + // This now-registered thread was previously being spied. + SpiedThread& spiedThread = mSpiedThreads[spiedThreadIndex]; + PROFILER_MARKER( + MakeThreadInfoMarkerName(spiedThread.mThreadId, spiedThread.mName), + PROFILER, + MarkerOptions( + MarkerThreadId::MainThread(), + // Place the end between this update and the previous one. + // TODO: Find the real time from the thread registration? + MarkerTiming::IntervalEnd(previousSpying + + (mLastSpying - previousSpying) / + int64_t(2))), + UnregisteredThreadLifetimeMarker, spiedThread.mThreadId, + spiedThread.mName, "Thread registered itself"); + + // Remove from mSpiedThreads, since it can be profiled normally. + mSpiedThreads.RemoveElement(threadInfo.tid); + } + } else { + // This thread id is not registered. + if (spiedThreadIndex == SpiedThreads::NoIndex) { + // This unregistered thread has not been spied yet, store it now. + NS_ConvertUTF16toUTF8 name(threadInfo.name); + mSpiedThreads.EmplaceBack(threadInfo.tid, name, threadInfo.cpuTime); + + PROFILER_MARKER( + MakeThreadInfoMarkerName(threadInfo.tid, name), PROFILER, + MarkerOptions( + MarkerThreadId::MainThread(), + // Place the start between this update and the previous one (or + // the start of this search if it's the first one). + MarkerTiming::IntervalStart( + mLastSpying - + (mLastSpying - (previousSpying.IsNull() + ? unregisteredThreadSearchStart + : previousSpying)) / + int64_t(2))), + UnregisteredThreadLifetimeMarker, threadInfo.tid, name, + /* aEndEvent */ ""); + } else { + // This unregistered thread was already being spied, record its work. + SpiedThread& spiedThread = mSpiedThreads[spiedThreadIndex]; + int64_t diffCPUTimeNs = + int64_t(threadInfo.cpuTime) - int64_t(spiedThread.mCPUTimeNs); + spiedThread.mCPUTimeNs = threadInfo.cpuTime; + if (diffCPUTimeNs != 0) { + PROFILER_MARKER( + MakeThreadInfoMarkerName(threadInfo.tid, spiedThread.mName), + PROFILER, + MarkerOptions( + MarkerThreadId::MainThread(), + MarkerTiming::Interval(previousSpying, mLastSpying)), + UnregisteredThreadCPUMarker, threadInfo.tid, diffCPUTimeNs, + previousSpying, mLastSpying); + } + } + } + } + + PROFILER_MARKER_TEXT("Unregistered thread search", PROFILER, + MarkerOptions(MarkerThreadId::MainThread(), + MarkerTiming::IntervalUntilNowFrom( + unregisteredThreadSearchStart)), + "Work to discover and record unregistered threads"); +} + +// We #include these files directly because it means those files can use +// declarations from this file trivially. These provide target-specific +// implementations of all SamplerThread methods except Run(). +#if defined(GP_OS_windows) +# include "platform-win32.cpp" +#elif defined(GP_OS_darwin) +# include "platform-macos.cpp" +#elif defined(GP_OS_linux) || defined(GP_OS_android) || defined(GP_OS_freebsd) +# include "platform-linux-android.cpp" +#else +# error "bad platform" +#endif + +// END SamplerThread +//////////////////////////////////////////////////////////////////////// + +//////////////////////////////////////////////////////////////////////// +// BEGIN externally visible functions + +MOZ_DEFINE_MALLOC_SIZE_OF(GeckoProfilerMallocSizeOf) + +NS_IMETHODIMP +GeckoProfilerReporter::CollectReports(nsIHandleReportCallback* aHandleReport, + nsISupports* aData, bool aAnonymize) { + MOZ_RELEASE_ASSERT(NS_IsMainThread()); + + size_t profSize = 0; + size_t lulSize = 0; + + { + PSAutoLock lock; + + if (CorePS::Exists()) { + CorePS::AddSizeOf(lock, GeckoProfilerMallocSizeOf, profSize, lulSize); + } + + if (ActivePS::Exists(lock)) { + profSize += ActivePS::SizeOf(lock, GeckoProfilerMallocSizeOf); + } + } + + MOZ_COLLECT_REPORT( + "explicit/profiler/profiler-state", KIND_HEAP, UNITS_BYTES, profSize, + "Memory used by the Gecko Profiler's global state (excluding memory used " + "by LUL)."); + +#if defined(USE_LUL_STACKWALK) + MOZ_COLLECT_REPORT( + "explicit/profiler/lul", KIND_HEAP, UNITS_BYTES, lulSize, + "Memory used by LUL, a stack unwinder used by the Gecko Profiler."); +#endif + + return NS_OK; +} + +NS_IMPL_ISUPPORTS(GeckoProfilerReporter, nsIMemoryReporter) + +static uint32_t ParseFeature(const char* aFeature, bool aIsStartup) { + if (strcmp(aFeature, "default") == 0) { + return (aIsStartup ? (DefaultFeatures() | StartupExtraDefaultFeatures()) + : DefaultFeatures()) & + AvailableFeatures(); + } + +#define PARSE_FEATURE_BIT(n_, str_, Name_, desc_) \ + if (strcmp(aFeature, str_) == 0) { \ + return ProfilerFeature::Name_; \ + } + + PROFILER_FOR_EACH_FEATURE(PARSE_FEATURE_BIT) + +#undef PARSE_FEATURE_BIT + + printf("\nUnrecognized feature \"%s\".\n\n", aFeature); + // Since we may have an old feature we don't implement anymore, don't exit. + PrintUsage(); + return 0; +} + +uint32_t ParseFeaturesFromStringArray(const char** aFeatures, + uint32_t aFeatureCount, + bool aIsStartup /* = false */) { + uint32_t features = 0; + for (size_t i = 0; i < aFeatureCount; i++) { + features |= ParseFeature(aFeatures[i], aIsStartup); + } + return features; +} + +static ProfilingStack* locked_register_thread( + PSLockRef aLock, ThreadRegistry::OffThreadRef aOffThreadRef) { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + VTUNE_REGISTER_THREAD(aOffThreadRef.UnlockedConstReaderCRef().Info().Name()); + + if (ActivePS::Exists(aLock)) { + ThreadProfilingFeatures threadProfilingFeatures = + ActivePS::ProfilingFeaturesForThread( + aLock, aOffThreadRef.UnlockedConstReaderCRef().Info()); + if (threadProfilingFeatures != ThreadProfilingFeatures::NotProfiled) { + ThreadRegistry::OffThreadRef::RWFromAnyThreadWithLock + lockedRWFromAnyThread = aOffThreadRef.GetLockedRWFromAnyThread(); + + ProfiledThreadData* profiledThreadData = ActivePS::AddLiveProfiledThread( + aLock, MakeUnique<ProfiledThreadData>( + aOffThreadRef.UnlockedConstReaderCRef().Info())); + lockedRWFromAnyThread->SetProfilingFeaturesAndData( + threadProfilingFeatures, profiledThreadData, aLock); + + if (ActivePS::FeatureJS(aLock)) { + lockedRWFromAnyThread->StartJSSampling(ActivePS::JSFlags(aLock)); + if (ThreadRegistration::LockedRWOnThread* lockedRWOnThread = + lockedRWFromAnyThread.GetLockedRWOnThread(); + lockedRWOnThread) { + // We can manually poll the current thread so it starts sampling + // immediately. + lockedRWOnThread->PollJSSampling(); + } + if (lockedRWFromAnyThread->GetJSContext()) { + profiledThreadData->NotifyReceivedJSContext( + ActivePS::Buffer(aLock).BufferRangeEnd()); + } + } + } + } + + return &aOffThreadRef.UnlockedConstReaderAndAtomicRWRef().ProfilingStackRef(); +} + +static void NotifyObservers(const char* aTopic, + nsISupports* aSubject = nullptr) { + if (!NS_IsMainThread()) { + // Dispatch a task to the main thread that notifies observers. + // If NotifyObservers is called both on and off the main thread within a + // short time, the order of the notifications can be different from the + // order of the calls to NotifyObservers. + // Getting the order 100% right isn't that important at the moment, because + // these notifications are only observed in the parent process, where the + // profiler_* functions are currently only called on the main thread. + nsCOMPtr<nsISupports> subject = aSubject; + NS_DispatchToMainThread(NS_NewRunnableFunction( + "NotifyObservers", [=] { NotifyObservers(aTopic, subject); })); + return; + } + + if (nsCOMPtr<nsIObserverService> os = services::GetObserverService()) { + os->NotifyObservers(aSubject, aTopic, nullptr); + } +} + +[[nodiscard]] static RefPtr<GenericPromise> NotifyProfilerStarted( + const PowerOfTwo32& aCapacity, const Maybe<double>& aDuration, + double aInterval, uint32_t aFeatures, const char** aFilters, + uint32_t aFilterCount, uint64_t aActiveTabID) { + nsTArray<nsCString> filtersArray; + for (size_t i = 0; i < aFilterCount; ++i) { + filtersArray.AppendElement(aFilters[i]); + } + + nsCOMPtr<nsIProfilerStartParams> params = new nsProfilerStartParams( + aCapacity.Value(), aDuration, aInterval, aFeatures, + std::move(filtersArray), aActiveTabID); + + RefPtr<GenericPromise> startPromise = ProfilerParent::ProfilerStarted(params); + NotifyObservers("profiler-started", params); + return startPromise; +} + +static void locked_profiler_start(PSLockRef aLock, PowerOfTwo32 aCapacity, + double aInterval, uint32_t aFeatures, + const char** aFilters, uint32_t aFilterCount, + uint64_t aActiveTabID, + const Maybe<double>& aDuration); + +// This basically duplicates AutoProfilerLabel's constructor. +static void* MozGlueLabelEnter(const char* aLabel, const char* aDynamicString, + void* aSp) { + ThreadRegistration::OnThreadPtr onThreadPtr = + ThreadRegistration::GetOnThreadPtr(); + if (!onThreadPtr) { + return nullptr; + } + ProfilingStack& profilingStack = + onThreadPtr->UnlockedConstReaderAndAtomicRWRef().ProfilingStackRef(); + profilingStack.pushLabelFrame(aLabel, aDynamicString, aSp, + JS::ProfilingCategoryPair::OTHER); + return &profilingStack; +} + +// This basically duplicates AutoProfilerLabel's destructor. +static void MozGlueLabelExit(void* aProfilingStack) { + if (aProfilingStack) { + reinterpret_cast<ProfilingStack*>(aProfilingStack)->pop(); + } +} + +static Vector<const char*> SplitAtCommas(const char* aString, + UniquePtr<char[]>& aStorage) { + size_t len = strlen(aString); + aStorage = MakeUnique<char[]>(len + 1); + PodCopy(aStorage.get(), aString, len + 1); + + // Iterate over all characters in aStorage and split at commas, by + // overwriting commas with the null char. + Vector<const char*> array; + size_t currentElementStart = 0; + for (size_t i = 0; i <= len; i++) { + if (aStorage[i] == ',') { + aStorage[i] = '\0'; + } + if (aStorage[i] == '\0') { + // Only add non-empty elements, otherwise ParseFeatures would later + // complain about unrecognized features. + if (currentElementStart != i) { + MOZ_RELEASE_ASSERT(array.append(&aStorage[currentElementStart])); + } + currentElementStart = i + 1; + } + } + return array; +} + +void profiler_init_threadmanager() { + LOG("profiler_init_threadmanager"); + + ThreadRegistration::WithOnThreadRef( + [](ThreadRegistration::OnThreadRef aOnThreadRef) { + aOnThreadRef.WithLockedRWOnThread( + [](ThreadRegistration::LockedRWOnThread& aThreadData) { + if (!aThreadData.GetEventTarget()) { + aThreadData.ResetMainThread(NS_GetCurrentThreadNoCreate()); + } + }); + }); +} + +static const char* get_size_suffix(const char* str) { + const char* ptr = str; + + while (isdigit(*ptr)) { + ptr++; + } + + return ptr; +} + +void profiler_init(void* aStackTop) { + LOG("profiler_init"); + + profiler_init_main_thread_id(); + + VTUNE_INIT(); + ETW::Init(); + + MOZ_RELEASE_ASSERT(!CorePS::Exists()); + + if (getenv("MOZ_PROFILER_HELP")) { + PrintUsage(); + exit(0); + } + + SharedLibraryInfo::Initialize(); + + uint32_t features = DefaultFeatures() & AvailableFeatures(); + + UniquePtr<char[]> filterStorage; + + Vector<const char*> filters; + MOZ_RELEASE_ASSERT(filters.append("GeckoMain")); + MOZ_RELEASE_ASSERT(filters.append("Compositor")); + MOZ_RELEASE_ASSERT(filters.append("Renderer")); + MOZ_RELEASE_ASSERT(filters.append("DOM Worker")); + + PowerOfTwo32 capacity = PROFILER_DEFAULT_ENTRIES; + Maybe<double> duration = Nothing(); + double interval = PROFILER_DEFAULT_INTERVAL; + uint64_t activeTabID = PROFILER_DEFAULT_ACTIVE_TAB_ID; + + ThreadRegistration::RegisterThread(kMainThreadName, aStackTop); + + { + PSAutoLock lock; + + // We've passed the possible failure point. Instantiate CorePS, which + // indicates that the profiler has initialized successfully. + CorePS::Create(lock); + + // Make sure threads already in the ThreadRegistry (like the main thread) + // get registered in CorePS as well. + { + ThreadRegistry::LockedRegistry lockedRegistry; + for (ThreadRegistry::OffThreadRef offThreadRef : lockedRegistry) { + locked_register_thread(lock, offThreadRef); + } + } + + // Platform-specific initialization. + PlatformInit(lock); + +#if defined(GP_OS_android) + if (jni::IsAvailable()) { + GeckoJavaSampler::Init(); + } +#endif + + // (Linux-only) We could create CorePS::mLul and read unwind info into it + // at this point. That would match the lifetime implied by destruction of + // it in profiler_shutdown() just below. However, that gives a big delay on + // startup, even if no profiling is actually to be done. So, instead, it is + // created on demand at the first call to PlatformStart(). + + const char* startupEnv = getenv("MOZ_PROFILER_STARTUP"); + if (!startupEnv || startupEnv[0] == '\0' || + ((startupEnv[0] == '0' || startupEnv[0] == 'N' || + startupEnv[0] == 'n') && + startupEnv[1] == '\0')) { + return; + } + + LOG("- MOZ_PROFILER_STARTUP is set"); + + // Startup default capacity may be different. + capacity = PROFILER_DEFAULT_STARTUP_ENTRIES; + + const char* startupCapacity = getenv("MOZ_PROFILER_STARTUP_ENTRIES"); + if (startupCapacity && startupCapacity[0] != '\0') { + errno = 0; + long capacityLong = strtol(startupCapacity, nullptr, 10); + std::string_view sizeSuffix = get_size_suffix(startupCapacity); + + if (sizeSuffix == "KB") { + capacityLong *= 1000 / scBytesPerEntry; + } else if (sizeSuffix == "KiB") { + capacityLong *= 1024 / scBytesPerEntry; + } else if (sizeSuffix == "MB") { + capacityLong *= (1000 * 1000) / scBytesPerEntry; + } else if (sizeSuffix == "MiB") { + capacityLong *= (1024 * 1024) / scBytesPerEntry; + } else if (sizeSuffix == "GB") { + capacityLong *= (1000 * 1000 * 1000) / scBytesPerEntry; + } else if (sizeSuffix == "GiB") { + capacityLong *= (1024 * 1024 * 1024) / scBytesPerEntry; + } else if (!sizeSuffix.empty()) { + LOG("- MOZ_PROFILER_STARTUP_ENTRIES unit must be one of the " + "following: KB, KiB, MB, MiB, GB, GiB"); + PrintUsage(); + exit(1); + } + + // `long` could be 32 or 64 bits, so we force a 64-bit comparison with + // the maximum 32-bit signed number (as more than that is clamped down to + // 2^31 anyway). + if (errno == 0 && capacityLong > 0 && + static_cast<uint64_t>(capacityLong) <= + static_cast<uint64_t>(INT32_MAX)) { + capacity = PowerOfTwo32( + ClampToAllowedEntries(static_cast<uint32_t>(capacityLong))); + LOG("- MOZ_PROFILER_STARTUP_ENTRIES = %u", unsigned(capacity.Value())); + } else { + LOG("- MOZ_PROFILER_STARTUP_ENTRIES not a valid integer: %s", + startupCapacity); + PrintUsage(); + exit(1); + } + } + + const char* startupDuration = getenv("MOZ_PROFILER_STARTUP_DURATION"); + if (startupDuration && startupDuration[0] != '\0') { + errno = 0; + double durationVal = PR_strtod(startupDuration, nullptr); + if (errno == 0 && durationVal >= 0.0) { + if (durationVal > 0.0) { + duration = Some(durationVal); + } + LOG("- MOZ_PROFILER_STARTUP_DURATION = %f", durationVal); + } else { + LOG("- MOZ_PROFILER_STARTUP_DURATION not a valid float: %s", + startupDuration); + PrintUsage(); + exit(1); + } + } + + const char* startupInterval = getenv("MOZ_PROFILER_STARTUP_INTERVAL"); + if (startupInterval && startupInterval[0] != '\0') { + errno = 0; + interval = PR_strtod(startupInterval, nullptr); + if (errno == 0 && interval > 0.0 && interval <= PROFILER_MAX_INTERVAL) { + LOG("- MOZ_PROFILER_STARTUP_INTERVAL = %f", interval); + } else { + LOG("- MOZ_PROFILER_STARTUP_INTERVAL not a valid float: %s", + startupInterval); + PrintUsage(); + exit(1); + } + } + + features |= StartupExtraDefaultFeatures() & AvailableFeatures(); + + const char* startupFeaturesBitfield = + getenv("MOZ_PROFILER_STARTUP_FEATURES_BITFIELD"); + if (startupFeaturesBitfield && startupFeaturesBitfield[0] != '\0') { + errno = 0; + features = strtol(startupFeaturesBitfield, nullptr, 10); + if (errno == 0) { + LOG("- MOZ_PROFILER_STARTUP_FEATURES_BITFIELD = %d", features); + } else { + LOG("- MOZ_PROFILER_STARTUP_FEATURES_BITFIELD not a valid integer: %s", + startupFeaturesBitfield); + PrintUsage(); + exit(1); + } + } else { + const char* startupFeatures = getenv("MOZ_PROFILER_STARTUP_FEATURES"); + if (startupFeatures) { + // Interpret startupFeatures as a list of feature strings, separated by + // commas. + UniquePtr<char[]> featureStringStorage; + Vector<const char*> featureStringArray = + SplitAtCommas(startupFeatures, featureStringStorage); + features = ParseFeaturesFromStringArray(featureStringArray.begin(), + featureStringArray.length(), + /* aIsStartup */ true); + LOG("- MOZ_PROFILER_STARTUP_FEATURES = %d", features); + } + } + + const char* startupFilters = getenv("MOZ_PROFILER_STARTUP_FILTERS"); + if (startupFilters && startupFilters[0] != '\0') { + filters = SplitAtCommas(startupFilters, filterStorage); + LOG("- MOZ_PROFILER_STARTUP_FILTERS = %s", startupFilters); + + if (mozilla::profiler::detail::FiltersExcludePid(filters)) { + LOG(" -> This process is excluded and won't be profiled"); + return; + } + } + + const char* startupActiveTabID = + getenv("MOZ_PROFILER_STARTUP_ACTIVE_TAB_ID"); + if (startupActiveTabID && startupActiveTabID[0] != '\0') { + std::istringstream iss(startupActiveTabID); + iss >> activeTabID; + if (!iss.fail()) { + LOG("- MOZ_PROFILER_STARTUP_ACTIVE_TAB_ID = %" PRIu64, activeTabID); + } else { + LOG("- MOZ_PROFILER_STARTUP_ACTIVE_TAB_ID not a valid " + "uint64_t: %s", + startupActiveTabID); + PrintUsage(); + exit(1); + } + } + + locked_profiler_start(lock, capacity, interval, features, filters.begin(), + filters.length(), activeTabID, duration); + } + + // The GeckoMain thread registration happened too early to record a marker, + // so let's record it again now. + profiler_mark_thread_awake(); + +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + // Start counting memory allocations (outside of lock because this may call + // profiler_add_sampled_counter which would attempt to take the lock.) + ActivePS::SetMemoryCounter(mozilla::profiler::install_memory_hooks()); +#endif + + invoke_profiler_state_change_callbacks(ProfilingState::Started); + + // We do this with gPSMutex unlocked. The comment in profiler_stop() explains + // why. + Unused << NotifyProfilerStarted(capacity, duration, interval, features, + filters.begin(), filters.length(), 0); +} + +static void locked_profiler_save_profile_to_file( + PSLockRef aLock, const char* aFilename, + const PreRecordedMetaInformation& aPreRecordedMetaInformation, + bool aIsShuttingDown); + +static SamplerThread* locked_profiler_stop(PSLockRef aLock); + +void profiler_shutdown(IsFastShutdown aIsFastShutdown) { + LOG("profiler_shutdown"); + + VTUNE_SHUTDOWN(); + ETW::Shutdown(); + + MOZ_RELEASE_ASSERT(NS_IsMainThread()); + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + if (profiler_is_active()) { + invoke_profiler_state_change_callbacks(ProfilingState::Stopping); + } + invoke_profiler_state_change_callbacks(ProfilingState::ShuttingDown); + + const auto preRecordedMetaInformation = + PreRecordMetaInformation(/* aShutdown = */ true); + + ProfilerParent::ProfilerWillStopIfStarted(); + + // If the profiler is active we must get a handle to the SamplerThread before + // ActivePS is destroyed, in order to delete it. + SamplerThread* samplerThread = nullptr; + { + PSAutoLock lock; + + // Save the profile on shutdown if requested. + if (ActivePS::Exists(lock)) { + const char* filename = getenv("MOZ_PROFILER_SHUTDOWN"); + if (filename && filename[0] != '\0') { + locked_profiler_save_profile_to_file(lock, filename, + preRecordedMetaInformation, + /* aIsShuttingDown */ true); + } + if (aIsFastShutdown == IsFastShutdown::Yes) { + return; + } + + samplerThread = locked_profiler_stop(lock); + } else if (aIsFastShutdown == IsFastShutdown::Yes) { + return; + } + + CorePS::Destroy(lock); + } + + // We do these operations with gPSMutex unlocked. The comments in + // profiler_stop() explain why. + if (samplerThread) { + Unused << ProfilerParent::ProfilerStopped(); + NotifyObservers("profiler-stopped"); + delete samplerThread; + } + + // Reverse the registration done in profiler_init. + ThreadRegistration::UnregisterThread(); +} + +static bool WriteProfileToJSONWriter(SpliceableChunkedJSONWriter& aWriter, + double aSinceTime, bool aIsShuttingDown, + ProfilerCodeAddressService* aService, + mozilla::ProgressLogger aProgressLogger) { + LOG("WriteProfileToJSONWriter"); + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + aWriter.Start(); + { + auto rv = profiler_stream_json_for_this_process( + aWriter, aSinceTime, aIsShuttingDown, aService, + aProgressLogger.CreateSubLoggerFromTo( + 0_pc, + "WriteProfileToJSONWriter: " + "profiler_stream_json_for_this_process started", + 100_pc, + "WriteProfileToJSONWriter: " + "profiler_stream_json_for_this_process done")); + + if (rv.isErr()) { + return false; + } + + // Don't include profiles from other processes because this is a + // synchronous function. + aWriter.StartArrayProperty("processes"); + aWriter.EndArray(); + } + aWriter.End(); + return !aWriter.Failed(); +} + +void profiler_set_process_name(const nsACString& aProcessName, + const nsACString* aETLDplus1) { + LOG("profiler_set_process_name(\"%s\", \"%s\")", aProcessName.Data(), + aETLDplus1 ? aETLDplus1->Data() : "<none>"); + PSAutoLock lock; + CorePS::SetProcessName(lock, aProcessName); + if (aETLDplus1) { + CorePS::SetETLDplus1(lock, *aETLDplus1); + } +} + +UniquePtr<char[]> profiler_get_profile(double aSinceTime, + bool aIsShuttingDown) { + LOG("profiler_get_profile"); + + UniquePtr<ProfilerCodeAddressService> service = + profiler_code_address_service_for_presymbolication(); + + FailureLatchSource failureLatch; + SpliceableChunkedJSONWriter b{failureLatch}; + if (!WriteProfileToJSONWriter(b, aSinceTime, aIsShuttingDown, service.get(), + ProgressLogger{})) { + return nullptr; + } + return b.ChunkedWriteFunc().CopyData(); +} + +[[nodiscard]] bool profiler_get_profile_json( + SpliceableChunkedJSONWriter& aSpliceableChunkedJSONWriter, + double aSinceTime, bool aIsShuttingDown, + mozilla::ProgressLogger aProgressLogger) { + LOG("profiler_get_profile_json"); + + UniquePtr<ProfilerCodeAddressService> service = + profiler_code_address_service_for_presymbolication(); + + return WriteProfileToJSONWriter( + aSpliceableChunkedJSONWriter, aSinceTime, aIsShuttingDown, service.get(), + aProgressLogger.CreateSubLoggerFromTo( + 0.1_pc, "profiler_get_profile_json: WriteProfileToJSONWriter started", + 99.9_pc, "profiler_get_profile_json: WriteProfileToJSONWriter done")); +} + +void profiler_get_start_params(int* aCapacity, Maybe<double>* aDuration, + double* aInterval, uint32_t* aFeatures, + Vector<const char*>* aFilters, + uint64_t* aActiveTabID) { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + if (NS_WARN_IF(!aCapacity) || NS_WARN_IF(!aDuration) || + NS_WARN_IF(!aInterval) || NS_WARN_IF(!aFeatures) || + NS_WARN_IF(!aFilters)) { + return; + } + + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + *aCapacity = 0; + *aDuration = Nothing(); + *aInterval = 0; + *aFeatures = 0; + *aActiveTabID = 0; + aFilters->clear(); + return; + } + + *aCapacity = ActivePS::Capacity(lock).Value(); + *aDuration = ActivePS::Duration(lock); + *aInterval = ActivePS::Interval(lock); + *aFeatures = ActivePS::Features(lock); + *aActiveTabID = ActivePS::ActiveTabID(lock); + + const Vector<std::string>& filters = ActivePS::Filters(lock); + MOZ_ALWAYS_TRUE(aFilters->resize(filters.length())); + for (uint32_t i = 0; i < filters.length(); ++i) { + (*aFilters)[i] = filters[i].c_str(); + } +} + +ProfileBufferControlledChunkManager* profiler_get_controlled_chunk_manager() { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + PSAutoLock lock; + if (NS_WARN_IF(!ActivePS::Exists(lock))) { + return nullptr; + } + return &ActivePS::ControlledChunkManager(lock); +} + +namespace mozilla { + +void GetProfilerEnvVarsForChildProcess( + std::function<void(const char* key, const char* value)>&& aSetEnv) { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + aSetEnv("MOZ_PROFILER_STARTUP", ""); + return; + } + + aSetEnv("MOZ_PROFILER_STARTUP", "1"); + + // If MOZ_PROFILER_SHUTDOWN is defined, make sure it's empty in children, so + // that they don't attempt to write over that file. + if (getenv("MOZ_PROFILER_SHUTDOWN")) { + aSetEnv("MOZ_PROFILER_SHUTDOWN", ""); + } + + // Hidden option to stop Base Profiler, mostly due to Talos intermittents, + // see https://bugzilla.mozilla.org/show_bug.cgi?id=1638851#c3 + // TODO: Investigate root cause and remove this in bugs 1648324 and 1648325. + if (getenv("MOZ_PROFILER_STARTUP_NO_BASE")) { + aSetEnv("MOZ_PROFILER_STARTUP_NO_BASE", "1"); + } + + auto capacityString = + Smprintf("%u", unsigned(ActivePS::Capacity(lock).Value())); + aSetEnv("MOZ_PROFILER_STARTUP_ENTRIES", capacityString.get()); + + // Use AppendFloat instead of Smprintf with %f because the decimal + // separator used by %f is locale-dependent. But the string we produce needs + // to be parseable by strtod, which only accepts the period character as a + // decimal separator. AppendFloat always uses the period character. + nsCString intervalString; + intervalString.AppendFloat(ActivePS::Interval(lock)); + aSetEnv("MOZ_PROFILER_STARTUP_INTERVAL", intervalString.get()); + + auto featuresString = Smprintf("%d", ActivePS::Features(lock)); + aSetEnv("MOZ_PROFILER_STARTUP_FEATURES_BITFIELD", featuresString.get()); + + std::string filtersString; + const Vector<std::string>& filters = ActivePS::Filters(lock); + for (uint32_t i = 0; i < filters.length(); ++i) { + if (i != 0) { + filtersString += ","; + } + filtersString += filters[i]; + } + aSetEnv("MOZ_PROFILER_STARTUP_FILTERS", filtersString.c_str()); + + auto activeTabIDString = Smprintf("%" PRIu64, ActivePS::ActiveTabID(lock)); + aSetEnv("MOZ_PROFILER_STARTUP_ACTIVE_TAB_ID", activeTabIDString.get()); +} + +} // namespace mozilla + +void profiler_received_exit_profile(const nsACString& aExitProfile) { + MOZ_RELEASE_ASSERT(NS_IsMainThread()); + MOZ_RELEASE_ASSERT(CorePS::Exists()); + PSAutoLock lock; + if (!ActivePS::Exists(lock)) { + return; + } + ActivePS::AddExitProfile(lock, aExitProfile); +} + +Vector<nsCString> profiler_move_exit_profiles() { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + PSAutoLock lock; + Vector<nsCString> profiles; + if (ActivePS::Exists(lock)) { + profiles = ActivePS::MoveExitProfiles(lock); + } + return profiles; +} + +static void locked_profiler_save_profile_to_file( + PSLockRef aLock, const char* aFilename, + const PreRecordedMetaInformation& aPreRecordedMetaInformation, + bool aIsShuttingDown = false) { + nsAutoCString processedFilename(aFilename); + const auto processInsertionIndex = processedFilename.Find("%p"); + if (processInsertionIndex != kNotFound) { + // Replace "%p" with the process id. + nsAutoCString process; + process.AppendInt(profiler_current_process_id().ToNumber()); + processedFilename.Replace(processInsertionIndex, 2, process); + LOG("locked_profiler_save_profile_to_file(\"%s\" -> \"%s\")", aFilename, + processedFilename.get()); + } else { + LOG("locked_profiler_save_profile_to_file(\"%s\")", aFilename); + } + + MOZ_RELEASE_ASSERT(CorePS::Exists() && ActivePS::Exists(aLock)); + + std::ofstream stream; + stream.open(processedFilename.get()); + if (stream.is_open()) { + OStreamJSONWriteFunc sw(stream); + SpliceableJSONWriter w(sw, FailureLatchInfallibleSource::Singleton()); + w.Start(); + { + Unused << locked_profiler_stream_json_for_this_process( + aLock, w, /* sinceTime */ 0, aPreRecordedMetaInformation, + aIsShuttingDown, nullptr, ProgressLogger{}); + + w.StartArrayProperty("processes"); + Vector<nsCString> exitProfiles = ActivePS::MoveExitProfiles(aLock); + for (auto& exitProfile : exitProfiles) { + if (!exitProfile.IsEmpty() && exitProfile[0] != '*') { + w.Splice(exitProfile); + } + } + w.EndArray(); + } + w.End(); + + stream.close(); + } +} + +void profiler_save_profile_to_file(const char* aFilename) { + LOG("profiler_save_profile_to_file(%s)", aFilename); + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + const auto preRecordedMetaInformation = PreRecordMetaInformation(); + + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + return; + } + + locked_profiler_save_profile_to_file(lock, aFilename, + preRecordedMetaInformation); +} + +uint32_t profiler_get_available_features() { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + return AvailableFeatures(); +} + +Maybe<ProfilerBufferInfo> profiler_get_buffer_info() { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + return Nothing(); + } + + return Some(ActivePS::Buffer(lock).GetProfilerBufferInfo()); +} + +static void PollJSSamplingForCurrentThread() { + ThreadRegistration::WithOnThreadRef( + [](ThreadRegistration::OnThreadRef aOnThreadRef) { + aOnThreadRef.WithLockedRWOnThread( + [](ThreadRegistration::LockedRWOnThread& aThreadData) { + aThreadData.PollJSSampling(); + }); + }); +} + +// When the profiler is started on a background thread, we can't synchronously +// call PollJSSampling on the main thread's ThreadInfo. And the next regular +// call to PollJSSampling on the main thread would only happen once the main +// thread triggers a JS interrupt callback. +// This means that all the JS execution between profiler_start() and the first +// JS interrupt would happen with JS sampling disabled, and we wouldn't get any +// JS function information for that period of time. +// So in order to start JS sampling as soon as possible, we dispatch a runnable +// to the main thread which manually calls PollJSSamplingForCurrentThread(). +// In some cases this runnable will lose the race with the next JS interrupt. +// That's fine; PollJSSamplingForCurrentThread() is immune to redundant calls. +static void TriggerPollJSSamplingOnMainThread() { + nsCOMPtr<nsIThread> mainThread; + nsresult rv = NS_GetMainThread(getter_AddRefs(mainThread)); + if (NS_SUCCEEDED(rv) && mainThread) { + nsCOMPtr<nsIRunnable> task = + NS_NewRunnableFunction("TriggerPollJSSamplingOnMainThread", + []() { PollJSSamplingForCurrentThread(); }); + SchedulerGroup::Dispatch(task.forget()); + } +} + +static void locked_profiler_start(PSLockRef aLock, PowerOfTwo32 aCapacity, + double aInterval, uint32_t aFeatures, + const char** aFilters, uint32_t aFilterCount, + uint64_t aActiveTabID, + const Maybe<double>& aDuration) { + TimeStamp profilingStartTime = TimeStamp::Now(); + + if (LOG_TEST) { + LOG("locked_profiler_start"); + LOG("- capacity = %u", unsigned(aCapacity.Value())); + LOG("- duration = %.2f", aDuration ? *aDuration : -1); + LOG("- interval = %.2f", aInterval); + LOG("- tab ID = %" PRIu64, aActiveTabID); + +#define LOG_FEATURE(n_, str_, Name_, desc_) \ + if (ProfilerFeature::Has##Name_(aFeatures)) { \ + LOG("- feature = %s", str_); \ + } + + PROFILER_FOR_EACH_FEATURE(LOG_FEATURE) + +#undef LOG_FEATURE + + for (uint32_t i = 0; i < aFilterCount; i++) { + LOG("- threads = %s", aFilters[i]); + } + } + + MOZ_RELEASE_ASSERT(CorePS::Exists() && !ActivePS::Exists(aLock)); + + // Do this before the Base Profiler is stopped, to keep the existing buffer + // (if any) alive for our use. + if (NS_IsMainThread()) { + mozilla::base_profiler_markers_detail::EnsureBufferForMainThreadAddMarker(); + } else { + NS_DispatchToMainThread( + NS_NewRunnableFunction("EnsureBufferForMainThreadAddMarker", + &mozilla::base_profiler_markers_detail:: + EnsureBufferForMainThreadAddMarker)); + } + + UniquePtr<ProfileBufferChunkManagerWithLocalLimit> baseChunkManager; + bool profilersHandOver = false; + if (baseprofiler::profiler_is_active()) { + // Note that we still hold the lock, so the sampler cannot run yet and + // interact negatively with the still-active BaseProfiler sampler. + // Assume that Base Profiler is active because of MOZ_PROFILER_STARTUP. + + // Take ownership of the chunk manager from the Base Profiler, to extend its + // lifetime during the new Gecko Profiler session. Since we're using the + // same core buffer, all the base profiler data remains. + baseChunkManager = baseprofiler::detail::ExtractBaseProfilerChunkManager(); + + if (baseChunkManager) { + profilersHandOver = true; + if (const TimeStamp baseProfilingStartTime = + baseprofiler::detail::GetProfilingStartTime(); + !baseProfilingStartTime.IsNull()) { + profilingStartTime = baseProfilingStartTime; + } + + BASE_PROFILER_MARKER_TEXT( + "Profilers handover", PROFILER, MarkerTiming::IntervalStart(), + "Transition from Base to Gecko Profiler, some data may be missing"); + } + + // Now stop Base Profiler (BP), as further recording will be ignored anyway, + // and so that it won't clash with Gecko Profiler (GP) sampling starting + // after the lock is dropped. + // On Linux this is especially important to do before creating the GP + // sampler, because the BP sampler may send a signal (to stop threads to be + // sampled), which the GP would intercept before its own initialization is + // complete and ready to handle such signals. + // Note that even though `profiler_stop()` doesn't immediately destroy and + // join the sampler thread, it safely deactivates it in such a way that the + // thread will soon exit without doing any actual work. + // TODO: Allow non-sampling profiling to continue. + // TODO: Re-start BP after GP shutdown, to capture post-XPCOM shutdown. + baseprofiler::profiler_stop(); + } + +#if defined(GP_PLAT_amd64_windows) || defined(GP_PLAT_arm64_windows) + mozilla::WindowsStackWalkInitialization(); +#endif + + // Fall back to the default values if the passed-in values are unreasonable. + // We want to be able to store at least one full stack. + PowerOfTwo32 capacity = + (aCapacity.Value() >= + ProfileBufferChunkManager::scExpectedMaximumStackSize / scBytesPerEntry) + ? aCapacity + : PROFILER_DEFAULT_ENTRIES; + Maybe<double> duration = aDuration; + + if (aDuration && *aDuration <= 0) { + duration = Nothing(); + } + + double interval = aInterval > 0 ? aInterval : PROFILER_DEFAULT_INTERVAL; + + ActivePS::Create(aLock, profilingStartTime, capacity, interval, aFeatures, + aFilters, aFilterCount, aActiveTabID, duration, + std::move(baseChunkManager)); + + // ActivePS::Create can only succeed or crash. + MOZ_ASSERT(ActivePS::Exists(aLock)); + + // Set up profiling for each registered thread, if appropriate. +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + bool isMainThreadBeingProfiled = false; +#endif + ThreadRegistry::LockedRegistry lockedRegistry; + for (ThreadRegistry::OffThreadRef offThreadRef : lockedRegistry) { + const ThreadRegistrationInfo& info = + offThreadRef.UnlockedConstReaderCRef().Info(); + + ThreadProfilingFeatures threadProfilingFeatures = + ActivePS::ProfilingFeaturesForThread(aLock, info); + if (threadProfilingFeatures != ThreadProfilingFeatures::NotProfiled) { + ThreadRegistry::OffThreadRef::RWFromAnyThreadWithLock lockedThreadData = + offThreadRef.GetLockedRWFromAnyThread(); + ProfiledThreadData* profiledThreadData = ActivePS::AddLiveProfiledThread( + aLock, MakeUnique<ProfiledThreadData>(info)); + lockedThreadData->SetProfilingFeaturesAndData(threadProfilingFeatures, + profiledThreadData, aLock); + lockedThreadData->GetNewCpuTimeInNs(); + if (ActivePS::FeatureJS(aLock)) { + lockedThreadData->StartJSSampling(ActivePS::JSFlags(aLock)); + if (ThreadRegistration::LockedRWOnThread* lockedRWOnThread = + lockedThreadData.GetLockedRWOnThread(); + lockedRWOnThread) { + // We can manually poll the current thread so it starts sampling + // immediately. + lockedRWOnThread->PollJSSampling(); + } else if (info.IsMainThread()) { + // Dispatch a runnable to the main thread to call + // PollJSSampling(), so that we don't have wait for the next JS + // interrupt callback in order to start profiling JS. + TriggerPollJSSamplingOnMainThread(); + } + } +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + if (info.IsMainThread()) { + isMainThreadBeingProfiled = true; + } +#endif + lockedThreadData->ReinitializeOnResume(); + if (ActivePS::FeatureJS(aLock) && lockedThreadData->GetJSContext()) { + profiledThreadData->NotifyReceivedJSContext(0); + } + } + } + + // Setup support for pushing/popping labels in mozglue. + RegisterProfilerLabelEnterExit(MozGlueLabelEnter, MozGlueLabelExit); + +#if defined(GP_OS_android) + if (ActivePS::FeatureJava(aLock)) { + int javaInterval = interval; + // Java sampling doesn't accurately keep up with the sampling rate that is + // lower than 1ms. + if (javaInterval < 1) { + javaInterval = 1; + } + + JNIEnv* env = jni::GetEnvForThread(); + const auto& filters = ActivePS::Filters(aLock); + jni::ObjectArray::LocalRef javaFilters = + jni::ObjectArray::New<jni::String>(filters.length()); + for (size_t i = 0; i < filters.length(); i++) { + javaFilters->SetElement(i, jni::StringParam(filters[i].data(), env)); + } + + // Send the interval-relative entry count, but we have 100000 hard cap in + // the java code, it can't be more than that. + java::GeckoJavaSampler::Start( + javaFilters, javaInterval, + std::round((double)(capacity.Value()) * interval / + (double)(javaInterval))); + } +#endif + +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + if (ActivePS::FeatureNativeAllocations(aLock)) { + if (isMainThreadBeingProfiled) { + mozilla::profiler::enable_native_allocations(); + } else { + NS_WARNING( + "The nativeallocations feature is turned on, but the main thread is " + "not being profiled. The allocations are only stored on the main " + "thread."); + } + } +#endif + + if (ProfilerFeature::HasAudioCallbackTracing(aFeatures)) { + StartAudioCallbackTracing(); + } + + // At the very end, set up RacyFeatures. + RacyFeatures::SetActive(ActivePS::Features(aLock)); + + if (profilersHandOver) { + PROFILER_MARKER_UNTYPED("Profilers handover", PROFILER, + MarkerTiming::IntervalEnd()); + } +} + +RefPtr<GenericPromise> profiler_start(PowerOfTwo32 aCapacity, double aInterval, + uint32_t aFeatures, const char** aFilters, + uint32_t aFilterCount, + uint64_t aActiveTabID, + const Maybe<double>& aDuration) { + LOG("profiler_start"); + + ProfilerParent::ProfilerWillStopIfStarted(); + + SamplerThread* samplerThread = nullptr; + { + PSAutoLock lock; + + // Initialize if necessary. + if (!CorePS::Exists()) { + profiler_init(nullptr); + } + + // Reset the current state if the profiler is running. + if (ActivePS::Exists(lock)) { + // Note: Not invoking callbacks with ProfilingState::Stopping, because + // we're under lock, and also it would not be useful: Any profiling data + // will be discarded, and we're immediately restarting the profiler below + // and then notifying ProfilingState::Started. + samplerThread = locked_profiler_stop(lock); + } + + locked_profiler_start(lock, aCapacity, aInterval, aFeatures, aFilters, + aFilterCount, aActiveTabID, aDuration); + } + +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + // Start counting memory allocations (outside of lock because this may call + // profiler_add_sampled_counter which would attempt to take the lock.) + ActivePS::SetMemoryCounter(mozilla::profiler::install_memory_hooks()); +#endif + + invoke_profiler_state_change_callbacks(ProfilingState::Started); + + // We do these operations with gPSMutex unlocked. The comments in + // profiler_stop() explain why. + if (samplerThread) { + Unused << ProfilerParent::ProfilerStopped(); + NotifyObservers("profiler-stopped"); + delete samplerThread; + } + return NotifyProfilerStarted(aCapacity, aDuration, aInterval, aFeatures, + aFilters, aFilterCount, aActiveTabID); +} + +void profiler_ensure_started(PowerOfTwo32 aCapacity, double aInterval, + uint32_t aFeatures, const char** aFilters, + uint32_t aFilterCount, uint64_t aActiveTabID, + const Maybe<double>& aDuration) { + LOG("profiler_ensure_started"); + + ProfilerParent::ProfilerWillStopIfStarted(); + + bool startedProfiler = false; + SamplerThread* samplerThread = nullptr; + { + PSAutoLock lock; + + // Initialize if necessary. + if (!CorePS::Exists()) { + profiler_init(nullptr); + } + + if (ActivePS::Exists(lock)) { + // The profiler is active. + if (!ActivePS::Equals(lock, aCapacity, aDuration, aInterval, aFeatures, + aFilters, aFilterCount, aActiveTabID)) { + // Stop and restart with different settings. + // Note: Not invoking callbacks with ProfilingState::Stopping, because + // we're under lock, and also it would not be useful: Any profiling data + // will be discarded, and we're immediately restarting the profiler + // below and then notifying ProfilingState::Started. + samplerThread = locked_profiler_stop(lock); + locked_profiler_start(lock, aCapacity, aInterval, aFeatures, aFilters, + aFilterCount, aActiveTabID, aDuration); + startedProfiler = true; + } + } else { + // The profiler is stopped. + locked_profiler_start(lock, aCapacity, aInterval, aFeatures, aFilters, + aFilterCount, aActiveTabID, aDuration); + startedProfiler = true; + } + } + + // We do these operations with gPSMutex unlocked. The comments in + // profiler_stop() explain why. + if (samplerThread) { + Unused << ProfilerParent::ProfilerStopped(); + NotifyObservers("profiler-stopped"); + delete samplerThread; + } + + if (startedProfiler) { + invoke_profiler_state_change_callbacks(ProfilingState::Started); + + Unused << NotifyProfilerStarted(aCapacity, aDuration, aInterval, aFeatures, + aFilters, aFilterCount, aActiveTabID); + } +} + +[[nodiscard]] static SamplerThread* locked_profiler_stop(PSLockRef aLock) { + LOG("locked_profiler_stop"); + + MOZ_RELEASE_ASSERT(CorePS::Exists() && ActivePS::Exists(aLock)); + + // At the very start, clear RacyFeatures. + RacyFeatures::SetInactive(); + + if (ActivePS::FeatureAudioCallbackTracing(aLock)) { + StopAudioCallbackTracing(); + } + +#if defined(GP_OS_android) + if (ActivePS::FeatureJava(aLock)) { + java::GeckoJavaSampler::Stop(); + } +#endif + + // Remove support for pushing/popping labels in mozglue. + RegisterProfilerLabelEnterExit(nullptr, nullptr); + + // Stop sampling live threads. + ThreadRegistry::LockedRegistry lockedRegistry; + for (ThreadRegistry::OffThreadRef offThreadRef : lockedRegistry) { + if (offThreadRef.UnlockedRWForLockedProfilerRef().ProfilingFeatures() == + ThreadProfilingFeatures::NotProfiled) { + continue; + } + + ThreadRegistry::OffThreadRef::RWFromAnyThreadWithLock lockedThreadData = + offThreadRef.GetLockedRWFromAnyThread(); + + lockedThreadData->ClearProfilingFeaturesAndData(aLock); + + if (ActivePS::FeatureJS(aLock)) { + lockedThreadData->StopJSSampling(); + if (ThreadRegistration::LockedRWOnThread* lockedRWOnThread = + lockedThreadData.GetLockedRWOnThread(); + lockedRWOnThread) { + // We are on the thread, we can manually poll the current thread so it + // stops profiling immediately. + lockedRWOnThread->PollJSSampling(); + } else if (lockedThreadData->Info().IsMainThread()) { + // Dispatch a runnable to the main thread to call PollJSSampling(), + // so that we don't have wait for the next JS interrupt callback in + // order to start profiling JS. + TriggerPollJSSamplingOnMainThread(); + } + } + } + +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + if (ActivePS::FeatureNativeAllocations(aLock)) { + mozilla::profiler::disable_native_allocations(); + } +#endif + + // The Stop() call doesn't actually stop Run(); that happens in this + // function's caller when the sampler thread is destroyed. Stop() just gives + // the SamplerThread a chance to do some cleanup with gPSMutex locked. + SamplerThread* samplerThread = ActivePS::Destroy(aLock); + samplerThread->Stop(aLock); + + if (NS_IsMainThread()) { + mozilla::base_profiler_markers_detail:: + ReleaseBufferForMainThreadAddMarker(); + } else { + NS_DispatchToMainThread( + NS_NewRunnableFunction("ReleaseBufferForMainThreadAddMarker", + &mozilla::base_profiler_markers_detail:: + ReleaseBufferForMainThreadAddMarker)); + } + + return samplerThread; +} + +RefPtr<GenericPromise> profiler_stop() { + LOG("profiler_stop"); + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + if (profiler_is_active()) { + invoke_profiler_state_change_callbacks(ProfilingState::Stopping); + } + + ProfilerParent::ProfilerWillStopIfStarted(); + +#if defined(MOZ_REPLACE_MALLOC) && defined(MOZ_PROFILER_MEMORY) + // Remove the hooks early, as native allocations (if they are on) can be + // quite expensive. + mozilla::profiler::remove_memory_hooks(); +#endif + + SamplerThread* samplerThread; + { + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + return GenericPromise::CreateAndResolve(/* unused */ true, __func__); + } + + samplerThread = locked_profiler_stop(lock); + } + + // We notify observers with gPSMutex unlocked. Otherwise we might get a + // deadlock, if code run by these functions calls a profiler function that + // locks gPSMutex, for example when it wants to insert a marker. + // (This has been seen in practise in bug 1346356, when we were still firing + // these notifications synchronously.) + RefPtr<GenericPromise> promise = ProfilerParent::ProfilerStopped(); + NotifyObservers("profiler-stopped"); + + // We delete with gPSMutex unlocked. Otherwise we would get a deadlock: we + // would be waiting here with gPSMutex locked for SamplerThread::Run() to + // return so the join operation within the destructor can complete, but Run() + // needs to lock gPSMutex to return. + // + // Because this call occurs with gPSMutex unlocked, it -- including the final + // iteration of Run()'s loop -- must be able detect deactivation and return + // in a way that's safe with respect to other gPSMutex-locking operations + // that may have occurred in the meantime. + delete samplerThread; + + return promise; +} + +bool profiler_is_paused() { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + return false; + } + + return ActivePS::IsPaused(lock); +} + +/* [[nodiscard]] */ bool profiler_callback_after_sampling( + PostSamplingCallback&& aCallback) { + LOG("profiler_callback_after_sampling"); + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + PSAutoLock lock; + + return ActivePS::AppendPostSamplingCallback(lock, std::move(aCallback)); +} + +RefPtr<GenericPromise> profiler_pause() { + LOG("profiler_pause"); + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + invoke_profiler_state_change_callbacks(ProfilingState::Pausing); + + { + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + return GenericPromise::CreateAndResolve(/* unused */ true, __func__); + } + +#if defined(GP_OS_android) + if (ActivePS::FeatureJava(lock) && !ActivePS::IsSamplingPaused(lock)) { + // Not paused yet, so this is the first pause, let Java know. + // TODO: Distinguish Pause and PauseSampling in Java. + java::GeckoJavaSampler::PauseSampling(); + } +#endif + + RacyFeatures::SetPaused(); + ActivePS::SetIsPaused(lock, true); + ActivePS::Buffer(lock).AddEntry(ProfileBufferEntry::Pause(profiler_time())); + } + + // gPSMutex must be unlocked when we notify, to avoid potential deadlocks. + RefPtr<GenericPromise> promise = ProfilerParent::ProfilerPaused(); + NotifyObservers("profiler-paused"); + return promise; +} + +RefPtr<GenericPromise> profiler_resume() { + LOG("profiler_resume"); + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + { + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + return GenericPromise::CreateAndResolve(/* unused */ true, __func__); + } + + ActivePS::Buffer(lock).AddEntry( + ProfileBufferEntry::Resume(profiler_time())); + ActivePS::SetIsPaused(lock, false); + RacyFeatures::SetUnpaused(); + +#if defined(GP_OS_android) + if (ActivePS::FeatureJava(lock) && !ActivePS::IsSamplingPaused(lock)) { + // Not paused anymore, so this is the last unpause, let Java know. + // TODO: Distinguish Unpause and UnpauseSampling in Java. + java::GeckoJavaSampler::UnpauseSampling(); + } +#endif + } + + // gPSMutex must be unlocked when we notify, to avoid potential deadlocks. + RefPtr<GenericPromise> promise = ProfilerParent::ProfilerResumed(); + NotifyObservers("profiler-resumed"); + + invoke_profiler_state_change_callbacks(ProfilingState::Resumed); + + return promise; +} + +bool profiler_is_sampling_paused() { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + return false; + } + + return ActivePS::IsSamplingPaused(lock); +} + +RefPtr<GenericPromise> profiler_pause_sampling() { + LOG("profiler_pause_sampling"); + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + { + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + return GenericPromise::CreateAndResolve(/* unused */ true, __func__); + } + +#if defined(GP_OS_android) + if (ActivePS::FeatureJava(lock) && !ActivePS::IsSamplingPaused(lock)) { + // Not paused yet, so this is the first pause, let Java know. + // TODO: Distinguish Pause and PauseSampling in Java. + java::GeckoJavaSampler::PauseSampling(); + } +#endif + + RacyFeatures::SetSamplingPaused(); + ActivePS::SetIsSamplingPaused(lock, true); + ActivePS::Buffer(lock).AddEntry( + ProfileBufferEntry::PauseSampling(profiler_time())); + } + + // gPSMutex must be unlocked when we notify, to avoid potential deadlocks. + RefPtr<GenericPromise> promise = ProfilerParent::ProfilerPausedSampling(); + NotifyObservers("profiler-paused-sampling"); + return promise; +} + +RefPtr<GenericPromise> profiler_resume_sampling() { + LOG("profiler_resume_sampling"); + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + { + PSAutoLock lock; + + if (!ActivePS::Exists(lock)) { + return GenericPromise::CreateAndResolve(/* unused */ true, __func__); + } + + ActivePS::Buffer(lock).AddEntry( + ProfileBufferEntry::ResumeSampling(profiler_time())); + ActivePS::SetIsSamplingPaused(lock, false); + RacyFeatures::SetSamplingUnpaused(); + +#if defined(GP_OS_android) + if (ActivePS::FeatureJava(lock) && !ActivePS::IsSamplingPaused(lock)) { + // Not paused anymore, so this is the last unpause, let Java know. + // TODO: Distinguish Unpause and UnpauseSampling in Java. + java::GeckoJavaSampler::UnpauseSampling(); + } +#endif + } + + // gPSMutex must be unlocked when we notify, to avoid potential deadlocks. + RefPtr<GenericPromise> promise = ProfilerParent::ProfilerResumedSampling(); + NotifyObservers("profiler-resumed-sampling"); + return promise; +} + +bool profiler_feature_active(uint32_t aFeature) { + // This function runs both on and off the main thread. + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + // This function is hot enough that we use RacyFeatures, not ActivePS. + return RacyFeatures::IsActiveWithFeature(aFeature); +} + +bool profiler_active_without_feature(uint32_t aFeature) { + // This function runs both on and off the main thread. + + // This function is hot enough that we use RacyFeatures, not ActivePS. + return RacyFeatures::IsActiveWithoutFeature(aFeature); +} + +void profiler_write_active_configuration(JSONWriter& aWriter) { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + PSAutoLock lock; + ActivePS::WriteActiveConfiguration(lock, aWriter); +} + +void profiler_add_sampled_counter(BaseProfilerCount* aCounter) { + DEBUG_LOG("profiler_add_sampled_counter(%s)", aCounter->mLabel); + PSAutoLock lock; + locked_profiler_add_sampled_counter(lock, aCounter); +} + +void profiler_remove_sampled_counter(BaseProfilerCount* aCounter) { + DEBUG_LOG("profiler_remove_sampled_counter(%s)", aCounter->mLabel); + PSAutoLock lock; + locked_profiler_remove_sampled_counter(lock, aCounter); +} + +void profiler_count_bandwidth_bytes(int64_t aCount) { + NS_ASSERTION(profiler_feature_active(ProfilerFeature::Bandwidth), + "Should not call profiler_count_bandwidth_bytes when the " + "Bandwidth feature is not set"); + + ProfilerBandwidthCounter* counter = CorePS::GetBandwidthCounter(); + if (MOZ_UNLIKELY(!counter)) { + counter = new ProfilerBandwidthCounter(); + CorePS::SetBandwidthCounter(counter); + } + + counter->Add(aCount); +} + +ProfilingStack* profiler_register_thread(const char* aName, + void* aGuessStackTop) { + DEBUG_LOG("profiler_register_thread(%s)", aName); + + // This will call `ThreadRegistry::Register()` (see below). + return ThreadRegistration::RegisterThread(aName, aGuessStackTop); +} + +/* static */ +void ThreadRegistry::Register(ThreadRegistration::OnThreadRef aOnThreadRef) { + // Set the thread name (except for the main thread, which is controlled + // elsewhere, and influences the process name on some systems like Linux). + if (!aOnThreadRef.UnlockedConstReaderCRef().Info().IsMainThread()) { + // Make sure we have a nsThread wrapper for the current thread, and that + // NSPR knows its name. + (void)NS_GetCurrentThread(); + NS_SetCurrentThreadName( + aOnThreadRef.UnlockedConstReaderCRef().Info().Name()); + } + + PSAutoLock lock; + + { + RegistryLockExclusive lock{sRegistryMutex}; + MOZ_RELEASE_ASSERT(sRegistryContainer.append(OffThreadRef{aOnThreadRef})); + } + + if (!CorePS::Exists()) { + // CorePS has not been created yet. + // If&when that happens, it will handle already-registered threads then. + return; + } + + (void)locked_register_thread(lock, OffThreadRef{aOnThreadRef}); +} + +void profiler_unregister_thread() { + // This will call `ThreadRegistry::Unregister()` (see below). + ThreadRegistration::UnregisterThread(); +} + +static void locked_unregister_thread( + PSLockRef lock, ThreadRegistration::OnThreadRef aOnThreadRef) { + if (!CorePS::Exists()) { + // This function can be called after the main thread has already shut + // down. + return; + } + + // We don't call StopJSSampling() here; there's no point doing that for a JS + // thread that is in the process of disappearing. + + ThreadRegistration::OnThreadRef::RWOnThreadWithLock lockedThreadData = + aOnThreadRef.GetLockedRWOnThread(); + + ProfiledThreadData* profiledThreadData = + lockedThreadData->GetProfiledThreadData(lock); + lockedThreadData->ClearProfilingFeaturesAndData(lock); + + MOZ_RELEASE_ASSERT( + lockedThreadData->Info().ThreadId() == profiler_current_thread_id(), + "Thread being unregistered has changed its TID"); + + DEBUG_LOG("profiler_unregister_thread: %s", lockedThreadData->Info().Name()); + + if (profiledThreadData && ActivePS::Exists(lock)) { + ActivePS::UnregisterThread(lock, profiledThreadData); + } +} + +/* static */ +void ThreadRegistry::Unregister(ThreadRegistration::OnThreadRef aOnThreadRef) { + PSAutoLock psLock; + locked_unregister_thread(psLock, aOnThreadRef); + + RegistryLockExclusive lock{sRegistryMutex}; + for (OffThreadRef& thread : sRegistryContainer) { + if (thread.IsPointingAt(*aOnThreadRef.mThreadRegistration)) { + sRegistryContainer.erase(&thread); + break; + } + } +} + +void profiler_register_page(uint64_t aTabID, uint64_t aInnerWindowID, + const nsCString& aUrl, + uint64_t aEmbedderInnerWindowID, + bool aIsPrivateBrowsing) { + DEBUG_LOG("profiler_register_page(%" PRIu64 ", %" PRIu64 ", %s, %" PRIu64 + ", %s)", + aTabID, aInnerWindowID, aUrl.get(), aEmbedderInnerWindowID, + aIsPrivateBrowsing ? "true" : "false"); + + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + PSAutoLock lock; + + // When a Browsing context is first loaded, the first url loaded in it will be + // about:blank. Because of that, this call keeps the first non-about:blank + // registration of window and discards the previous one. + RefPtr<PageInformation> pageInfo = new PageInformation( + aTabID, aInnerWindowID, aUrl, aEmbedderInnerWindowID, aIsPrivateBrowsing); + CorePS::AppendRegisteredPage(lock, std::move(pageInfo)); + + // After appending the given page to CorePS, look for the expired + // pages and remove them if there are any. + if (ActivePS::Exists(lock)) { + ActivePS::DiscardExpiredPages(lock); + } +} + +void profiler_unregister_page(uint64_t aRegisteredInnerWindowID) { + PSAutoLock lock; + + if (!CorePS::Exists()) { + // This function can be called after the main thread has already shut down. + return; + } + + // During unregistration, if the profiler is active, we have to keep the + // page information since there may be some markers associated with the given + // page. But if profiler is not active. we have no reason to keep the + // page information here because there can't be any marker associated with it. + if (ActivePS::Exists(lock)) { + ActivePS::UnregisterPage(lock, aRegisteredInnerWindowID); + } else { + CorePS::RemoveRegisteredPage(lock, aRegisteredInnerWindowID); + } +} + +void profiler_clear_all_pages() { + { + PSAutoLock lock; + + if (!CorePS::Exists()) { + // This function can be called after the main thread has already shut + // down. + return; + } + + CorePS::ClearRegisteredPages(lock); + if (ActivePS::Exists(lock)) { + ActivePS::ClearUnregisteredPages(lock); + } + } + + // gPSMutex must be unlocked when we notify, to avoid potential deadlocks. + ProfilerParent::ClearAllPages(); +} + +namespace geckoprofiler::markers::detail { + +Maybe<uint64_t> profiler_get_inner_window_id_from_docshell( + nsIDocShell* aDocshell) { + Maybe<uint64_t> innerWindowID = Nothing(); + if (aDocshell) { + auto outerWindow = aDocshell->GetWindow(); + if (outerWindow) { + auto innerWindow = outerWindow->GetCurrentInnerWindow(); + if (innerWindow) { + innerWindowID = Some(innerWindow->WindowID()); + } + } + } + return innerWindowID; +} + +} // namespace geckoprofiler::markers::detail + +namespace geckoprofiler::markers { + +struct CPUAwakeMarker { + static constexpr Span<const char> MarkerTypeName() { + return MakeStringSpan("Awake"); + } + static void StreamJSONMarkerData(baseprofiler::SpliceableJSONWriter& aWriter, + int64_t aCPUTimeNs, int64_t aCPUId +#ifdef GP_OS_darwin + , + uint32_t aQoS +#endif +#ifdef GP_OS_windows + , + int32_t aAbsolutePriority, + int32_t aRelativePriority, + int32_t aCurrentPriority +#endif + ) { + if (aCPUTimeNs) { + constexpr double NS_PER_MS = 1'000'000; + aWriter.DoubleProperty("CPU Time", double(aCPUTimeNs) / NS_PER_MS); + // CPU Time is only provided for the end marker, the other fields are for + // the start marker. + return; + } + +#ifndef GP_PLAT_arm64_darwin + aWriter.IntProperty("CPU Id", aCPUId); +#endif +#ifdef GP_OS_windows + if (aAbsolutePriority) { + aWriter.IntProperty("absPriority", aAbsolutePriority); + } + if (aCurrentPriority) { + aWriter.IntProperty("curPriority", aCurrentPriority); + } + aWriter.IntProperty("priority", aRelativePriority); +#endif +#ifdef GP_OS_darwin + const char* QoS = ""; + switch (aQoS) { + case QOS_CLASS_USER_INTERACTIVE: + QoS = "User Interactive"; + break; + case QOS_CLASS_USER_INITIATED: + QoS = "User Initiated"; + break; + case QOS_CLASS_DEFAULT: + QoS = "Default"; + break; + case QOS_CLASS_UTILITY: + QoS = "Utility"; + break; + case QOS_CLASS_BACKGROUND: + QoS = "Background"; + break; + default: + QoS = "Unspecified"; + } + + aWriter.StringProperty("QoS", + ProfilerString8View::WrapNullTerminatedString(QoS)); +#endif + } + + static MarkerSchema MarkerTypeDisplay() { + using MS = MarkerSchema; + MS schema{MS::Location::MarkerChart, MS::Location::MarkerTable}; + schema.AddKeyFormat("CPU Time", MS::Format::Duration); +#ifndef GP_PLAT_arm64_darwin + schema.AddKeyFormat("CPU Id", MS::Format::Integer); + schema.SetTableLabel("Awake - CPU Id = {marker.data.CPU Id}"); +#endif +#ifdef GP_OS_windows + schema.AddKeyLabelFormat("priority", "Relative Thread Priority", + MS::Format::Integer); + schema.AddKeyLabelFormat("absPriority", "Base Thread Priority", + MS::Format::Integer); + schema.AddKeyLabelFormat("curPriority", "Current Thread Priority", + MS::Format::Integer); +#endif +#ifdef GP_OS_darwin + schema.AddKeyLabelFormat("QoS", "Quality of Service", MS::Format::String); +#endif + return schema; + } +}; + +} // namespace geckoprofiler::markers + +void profiler_mark_thread_asleep() { + if (!profiler_thread_is_being_profiled_for_markers()) { + return; + } + + uint64_t cpuTimeNs = ThreadRegistration::WithOnThreadRefOr( + [](ThreadRegistration::OnThreadRef aOnThreadRef) { + return aOnThreadRef.UnlockedConstReaderAndAtomicRWRef() + .GetNewCpuTimeInNs(); + }, + 0); + PROFILER_MARKER("Awake", OTHER, MarkerTiming::IntervalEnd(), CPUAwakeMarker, + cpuTimeNs, 0 /* cpuId */ +#if defined(GP_OS_darwin) + , + 0 /* qos_class */ +#endif +#if defined(GP_OS_windows) + , + 0 /* priority */, 0 /* thread priority */, + 0 /* current priority */ +#endif + ); +} + +void profiler_thread_sleep() { + profiler_mark_thread_asleep(); + ThreadRegistration::WithOnThreadRef( + [](ThreadRegistration::OnThreadRef aOnThreadRef) { + aOnThreadRef.UnlockedConstReaderAndAtomicRWRef().SetSleeping(); + }); +} + +#if defined(GP_OS_windows) +# if !defined(__MINGW32__) +enum { + ThreadBasicInformation, +}; +# endif + +struct THREAD_BASIC_INFORMATION { + NTSTATUS ExitStatus; + PVOID TebBaseAddress; + CLIENT_ID ClientId; + KAFFINITY AffMask; + DWORD Priority; + DWORD BasePriority; +}; +#endif + +static mozilla::Atomic<uint64_t, mozilla::MemoryOrdering::Relaxed> gWakeCount( + 0); + +namespace geckoprofiler::markers { +struct WakeUpCountMarker { + static constexpr Span<const char> MarkerTypeName() { + return MakeStringSpan("WakeUpCount"); + } + static void StreamJSONMarkerData(baseprofiler::SpliceableJSONWriter& aWriter, + int32_t aCount, + const ProfilerString8View& aType) { + aWriter.IntProperty("Count", aCount); + aWriter.StringProperty("label", aType); + } + static MarkerSchema MarkerTypeDisplay() { + using MS = MarkerSchema; + MS schema{MS::Location::MarkerChart, MS::Location::MarkerTable}; + schema.AddKeyFormat("Count", MS::Format::Integer); + schema.SetTooltipLabel("{marker.name} - {marker.data.label}"); + schema.SetTableLabel( + "{marker.name} - {marker.data.label}: {marker.data.count}"); + return schema; + } +}; +} // namespace geckoprofiler::markers + +void profiler_record_wakeup_count(const nsACString& aProcessType) { + static uint64_t previousThreadWakeCount = 0; + + uint64_t newWakeups = gWakeCount - previousThreadWakeCount; + if (newWakeups > 0) { + if (newWakeups < std::numeric_limits<int32_t>::max()) { + int32_t newWakeups32 = int32_t(newWakeups); + mozilla::glean::power::total_thread_wakeups.Add(newWakeups32); + mozilla::glean::power::wakeups_per_process_type.Get(aProcessType) + .Add(newWakeups32); + PROFILER_MARKER("Thread Wake-ups", OTHER, {}, WakeUpCountMarker, + newWakeups32, aProcessType); + } + + previousThreadWakeCount += newWakeups; + } + +#ifdef NIGHTLY_BUILD + ThreadRegistry::LockedRegistry lockedRegistry; + for (ThreadRegistry::OffThreadRef offThreadRef : lockedRegistry) { + const ThreadRegistry::UnlockedConstReaderAndAtomicRW& threadData = + offThreadRef.UnlockedConstReaderAndAtomicRWRef(); + threadData.RecordWakeCount(); + } +#endif +} + +void profiler_mark_thread_awake() { + ++gWakeCount; + if (!profiler_thread_is_being_profiled_for_markers()) { + return; + } + + int64_t cpuId = 0; +#if defined(GP_OS_windows) + cpuId = GetCurrentProcessorNumber(); +#elif defined(GP_OS_darwin) +# ifdef GP_PLAT_amd64_darwin + unsigned int eax, ebx, ecx, edx; + __cpuid_count(1, 0, eax, ebx, ecx, edx); + // Check if we have an APIC. + if ((edx & (1 << 9))) { + // APIC ID is bits 24-31 of EBX + cpuId = ebx >> 24; + } +# endif +#else + cpuId = sched_getcpu(); +#endif + +#if defined(GP_OS_windows) + LONG priority; + static const auto get_thread_information_fn = + reinterpret_cast<decltype(&::GetThreadInformation)>(::GetProcAddress( + ::GetModuleHandle(L"Kernel32.dll"), "GetThreadInformation")); + + if (!get_thread_information_fn || + !get_thread_information_fn(GetCurrentThread(), ThreadAbsoluteCpuPriority, + &priority, sizeof(priority))) { + priority = 0; + } + + static const auto nt_query_information_thread_fn = + reinterpret_cast<decltype(&::NtQueryInformationThread)>(::GetProcAddress( + ::GetModuleHandle(L"ntdll.dll"), "NtQueryInformationThread")); + + LONG currentPriority = 0; + if (nt_query_information_thread_fn) { + THREAD_BASIC_INFORMATION threadInfo; + auto status = (*nt_query_information_thread_fn)( + GetCurrentThread(), (THREADINFOCLASS)ThreadBasicInformation, + &threadInfo, sizeof(threadInfo), NULL); + if (NT_SUCCESS(status)) { + currentPriority = threadInfo.Priority; + } + } +#endif + PROFILER_MARKER("Awake", OTHER, MarkerTiming::IntervalStart(), CPUAwakeMarker, + 0 /* CPU time */, cpuId +#if defined(GP_OS_darwin) + , + qos_class_self() +#endif +#if defined(GP_OS_windows) + , + priority, GetThreadPriority(GetCurrentThread()), + currentPriority +#endif + ); +} + +void profiler_thread_wake() { + profiler_mark_thread_awake(); + ThreadRegistration::WithOnThreadRef( + [](ThreadRegistration::OnThreadRef aOnThreadRef) { + aOnThreadRef.UnlockedConstReaderAndAtomicRWRef().SetAwake(); + }); +} + +void profiler_js_interrupt_callback() { + // This function runs on JS threads being sampled. + PollJSSamplingForCurrentThread(); +} + +double profiler_time() { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + TimeDuration delta = TimeStamp::Now() - CorePS::ProcessStartTime(); + return delta.ToMilliseconds(); +} + +bool profiler_capture_backtrace_into(ProfileChunkedBuffer& aChunkedBuffer, + StackCaptureOptions aCaptureOptions) { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + if (!profiler_is_active() || + aCaptureOptions == StackCaptureOptions::NoStack) { + return false; + } + + return ThreadRegistration::WithOnThreadRefOr( + [&](ThreadRegistration::OnThreadRef aOnThreadRef) { + mozilla::Maybe<uint32_t> maybeFeatures = + RacyFeatures::FeaturesIfActiveAndUnpaused(); + if (!maybeFeatures) { + return false; + } + + ProfileBuffer profileBuffer(aChunkedBuffer); + + Registers regs; +#if defined(HAVE_NATIVE_UNWIND) + REGISTERS_SYNC_POPULATE(regs); +#else + regs.Clear(); +#endif + + DoSyncSample(*maybeFeatures, + aOnThreadRef.UnlockedReaderAndAtomicRWOnThreadCRef(), + TimeStamp::Now(), regs, profileBuffer, aCaptureOptions); + + return true; + }, + // If this was called from a non-registered thread, return false and do no + // more work. This can happen from a memory hook. + false); +} + +UniquePtr<ProfileChunkedBuffer> profiler_capture_backtrace() { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + AUTO_PROFILER_LABEL_HOT("profiler_capture_backtrace", PROFILER); + + // Quick is-active and feature check before allocating a buffer. + // If NoMarkerStacks is set, we don't want to capture a backtrace. + if (!profiler_active_without_feature(ProfilerFeature::NoMarkerStacks)) { + return nullptr; + } + + auto buffer = MakeUnique<ProfileChunkedBuffer>( + ProfileChunkedBuffer::ThreadSafety::WithoutMutex, + MakeUnique<ProfileBufferChunkManagerSingle>( + ProfileBufferChunkManager::scExpectedMaximumStackSize)); + + if (!profiler_capture_backtrace_into(*buffer, StackCaptureOptions::Full)) { + return nullptr; + } + + return buffer; +} + +UniqueProfilerBacktrace profiler_get_backtrace() { + UniquePtr<ProfileChunkedBuffer> buffer = profiler_capture_backtrace(); + + if (!buffer) { + return nullptr; + } + + return UniqueProfilerBacktrace( + new ProfilerBacktrace("SyncProfile", std::move(buffer))); +} + +void ProfilerBacktraceDestructor::operator()(ProfilerBacktrace* aBacktrace) { + delete aBacktrace; +} + +bool profiler_is_locked_on_current_thread() { + // This function is used to help users avoid calling `profiler_...` functions + // when the profiler may already have a lock in place, which would prevent a + // 2nd recursive lock (resulting in a crash or a never-ending wait), or a + // deadlock between any two mutexes. So we must return `true` for any of: + // - The main profiler mutex, used by most functions, and/or + // - The buffer mutex, used directly in some functions without locking the + // main mutex, e.g., marker-related functions. + // - The ProfilerParent or ProfilerChild mutex, used to store and process + // buffer chunk updates. + return PSAutoLock::IsLockedOnCurrentThread() || + ThreadRegistry::IsRegistryMutexLockedOnCurrentThread() || + ThreadRegistration::IsDataMutexLockedOnCurrentThread() || + profiler_get_core_buffer().IsThreadSafeAndLockedOnCurrentThread() || + ProfilerParent::IsLockedOnCurrentThread() || + ProfilerChild::IsLockedOnCurrentThread(); +} + +void profiler_set_js_context(JSContext* aCx) { + MOZ_ASSERT(aCx); + ThreadRegistration::WithOnThreadRef( + [&](ThreadRegistration::OnThreadRef aOnThreadRef) { + // The profiler mutex must be locked before the ThreadRegistration's. + PSAutoLock lock; + aOnThreadRef.WithLockedRWOnThread( + [&](ThreadRegistration::LockedRWOnThread& aThreadData) { + aThreadData.SetJSContext(aCx); + + if (!ActivePS::Exists(lock) || !ActivePS::FeatureJS(lock)) { + return; + } + + // This call is on-thread, so we can call PollJSSampling() to + // start JS sampling immediately. + aThreadData.PollJSSampling(); + + if (ProfiledThreadData* profiledThreadData = + aThreadData.GetProfiledThreadData(lock); + profiledThreadData) { + profiledThreadData->NotifyReceivedJSContext( + ActivePS::Buffer(lock).BufferRangeEnd()); + } + }); + }); +} + +void profiler_clear_js_context() { + MOZ_RELEASE_ASSERT(CorePS::Exists()); + + ThreadRegistration::WithOnThreadRef( + [](ThreadRegistration::OnThreadRef aOnThreadRef) { + JSContext* cx = + aOnThreadRef.UnlockedReaderAndAtomicRWOnThreadCRef().GetJSContext(); + if (!cx) { + return; + } + + // The profiler mutex must be locked before the ThreadRegistration's. + PSAutoLock lock; + ThreadRegistration::OnThreadRef::RWOnThreadWithLock lockedThreadData = + aOnThreadRef.GetLockedRWOnThread(); + + if (ProfiledThreadData* profiledThreadData = + lockedThreadData->GetProfiledThreadData(lock); + profiledThreadData && ActivePS::Exists(lock) && + ActivePS::FeatureJS(lock)) { + profiledThreadData->NotifyAboutToLoseJSContext( + cx, CorePS::ProcessStartTime(), ActivePS::Buffer(lock)); + + // Notify the JS context that profiling for this context has + // stopped. Do this by calling StopJSSampling and PollJSSampling + // before nulling out the JSContext. + lockedThreadData->StopJSSampling(); + lockedThreadData->PollJSSampling(); + + lockedThreadData->ClearJSContext(); + + // Tell the thread that we'd like to have JS sampling on this + // thread again, once it gets a new JSContext (if ever). + lockedThreadData->StartJSSampling(ActivePS::JSFlags(lock)); + } else { + // This thread is not being profiled or JS profiling is off, we only + // need to clear the context pointer. + lockedThreadData->ClearJSContext(); + } + }); +} + +static void profiler_suspend_and_sample_thread( + const PSAutoLock* aLockIfAsynchronousSampling, + const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& aThreadData, + JsFrame* aJsFrames, uint32_t aFeatures, ProfilerStackCollector& aCollector, + bool aSampleNative) { + const ThreadRegistrationInfo& info = aThreadData.Info(); + + if (info.IsMainThread()) { + aCollector.SetIsMainThread(); + } + + // Allocate the space for the native stack + NativeStack nativeStack; + + auto collectStack = [&](const Registers& aRegs, const TimeStamp& aNow) { + // The target thread is now suspended. Collect a native backtrace, + // and call the callback. + StackWalkControl* stackWalkControlIfSupported = nullptr; +#if defined(HAVE_FASTINIT_NATIVE_UNWIND) + StackWalkControl stackWalkControl; + if constexpr (StackWalkControl::scIsSupported) { + if (aSampleNative) { + stackWalkControlIfSupported = &stackWalkControl; + } + } +#endif + const uint32_t jsFramesCount = + aJsFrames ? ExtractJsFrames(!aLockIfAsynchronousSampling, aThreadData, + aRegs, aCollector, aJsFrames, + stackWalkControlIfSupported) + : 0; + +#if defined(HAVE_FASTINIT_NATIVE_UNWIND) + if (aSampleNative) { + // We can only use FramePointerStackWalk or MozStackWalk from + // suspend_and_sample_thread as other stackwalking methods may not be + // initialized. +# if defined(USE_FRAME_POINTER_STACK_WALK) + DoFramePointerBacktrace(aThreadData, aRegs, nativeStack, + stackWalkControlIfSupported); +# elif defined(USE_MOZ_STACK_WALK) + DoMozStackWalkBacktrace(aThreadData, aRegs, nativeStack, + stackWalkControlIfSupported); +# else +# error "Invalid configuration" +# endif + + MergeStacks(aFeatures, !aLockIfAsynchronousSampling, aThreadData, aRegs, + nativeStack, aCollector, aJsFrames, jsFramesCount); + } else +#endif + { + MergeStacks(aFeatures, !aLockIfAsynchronousSampling, aThreadData, aRegs, + nativeStack, aCollector, aJsFrames, jsFramesCount); + + aCollector.CollectNativeLeafAddr((void*)aRegs.mPC); + } + }; + + if (!aLockIfAsynchronousSampling) { + // Sampling the current thread, do NOT suspend it! + Registers regs; +#if defined(HAVE_NATIVE_UNWIND) + REGISTERS_SYNC_POPULATE(regs); +#else + regs.Clear(); +#endif + collectStack(regs, TimeStamp::Now()); + } else { + // Suspend, sample, and then resume the target thread. + Sampler sampler(*aLockIfAsynchronousSampling); + TimeStamp now = TimeStamp::Now(); + sampler.SuspendAndSampleAndResumeThread(*aLockIfAsynchronousSampling, + aThreadData, now, collectStack); + + // NOTE: Make sure to disable the sampler before it is destroyed, in + // case the profiler is running at the same time. + sampler.Disable(*aLockIfAsynchronousSampling); + } +} + +// NOTE: aCollector's methods will be called while the target thread is paused. +// Doing things in those methods like allocating -- which may try to claim +// locks -- is a surefire way to deadlock. +void profiler_suspend_and_sample_thread(ProfilerThreadId aThreadId, + uint32_t aFeatures, + ProfilerStackCollector& aCollector, + bool aSampleNative /* = true */) { + if (!aThreadId.IsSpecified() || aThreadId == profiler_current_thread_id()) { + // Sampling the current thread. Get its information from the TLS (no locking + // required.) + ThreadRegistration::WithOnThreadRef( + [&](ThreadRegistration::OnThreadRef aOnThreadRef) { + aOnThreadRef.WithUnlockedReaderAndAtomicRWOnThread( + [&](const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& + aThreadData) { + if (!aThreadData.GetJSContext()) { + // No JSContext, there is no JS frame buffer (and no need for + // it). + profiler_suspend_and_sample_thread( + /* aLockIfAsynchronousSampling = */ nullptr, aThreadData, + /* aJsFrames = */ nullptr, aFeatures, aCollector, + aSampleNative); + } else { + // JSContext is present, we need to lock the thread data to + // access the JS frame buffer. + aOnThreadRef.WithConstLockedRWOnThread( + [&](const ThreadRegistration::LockedRWOnThread& + aLockedThreadData) { + profiler_suspend_and_sample_thread( + /* aLockIfAsynchronousSampling = */ nullptr, + aThreadData, aLockedThreadData.GetJsFrameBuffer(), + aFeatures, aCollector, aSampleNative); + }); + } + }); + }); + } else { + // Lock the profiler before accessing the ThreadRegistry. + PSAutoLock lock; + ThreadRegistry::WithOffThreadRef( + aThreadId, [&](ThreadRegistry::OffThreadRef aOffThreadRef) { + aOffThreadRef.WithLockedRWFromAnyThread( + [&](const ThreadRegistration::UnlockedReaderAndAtomicRWOnThread& + aThreadData) { + JsFrameBuffer& jsFrames = CorePS::JsFrames(lock); + profiler_suspend_and_sample_thread(&lock, aThreadData, jsFrames, + aFeatures, aCollector, + aSampleNative); + }); + }); + } +} + +// END externally visible functions +//////////////////////////////////////////////////////////////////////// |