diff options
Diffstat (limited to '')
| -rw-r--r-- | tools/profiler/public/GeckoProfiler.h | 435 |
1 files changed, 435 insertions, 0 deletions
diff --git a/tools/profiler/public/GeckoProfiler.h b/tools/profiler/public/GeckoProfiler.h new file mode 100644 index 0000000000..f7c045297e --- /dev/null +++ b/tools/profiler/public/GeckoProfiler.h @@ -0,0 +1,435 @@ +/* -*- Mode: C++; tab-width: 2; 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/. */ + +// The Gecko Profiler is an always-on profiler that takes fast and low overhead +// samples of the program execution using only userspace functionality for +// portability. The goal of this module is to provide performance data in a +// generic cross-platform way without requiring custom tools or kernel support. +// +// Samples are collected to form a timeline with optional timeline event +// (markers) used for filtering. The samples include both native stacks and +// platform-independent "label stack" frames. + +#ifndef GeckoProfiler_h +#define GeckoProfiler_h + +// Everything in here is also safe to include unconditionally, and only defines +// empty macros if MOZ_GECKO_PROFILER is unset. +// If your file only uses particular APIs (e.g., only markers), please consider +// including only the needed headers instead of this one, to reduce compilation +// dependencies. +#include "BaseProfiler.h" +#include "ProfileAdditionalInformation.h" +#include "mozilla/ProfilerCounts.h" +#include "mozilla/ProfilerLabels.h" +#include "mozilla/ProfilerMarkers.h" +#include "mozilla/ProfilerState.h" +#include "mozilla/ProfilerThreadSleep.h" +#include "mozilla/ProfilerThreadState.h" +#include "mozilla/ProgressLogger.h" +#include "mozilla/Result.h" +#include "mozilla/ResultVariant.h" + +#ifndef MOZ_GECKO_PROFILER + +# include "mozilla/UniquePtr.h" + +// This file can be #included unconditionally. However, everything within this +// file must be guarded by a #ifdef MOZ_GECKO_PROFILER, *except* for the +// following macros and functions, which encapsulate the most common operations +// and thus avoid the need for many #ifdefs. + +# define PROFILER_REGISTER_THREAD(name) +# define PROFILER_UNREGISTER_THREAD() +# define AUTO_PROFILER_REGISTER_THREAD(name) + +# define PROFILER_JS_INTERRUPT_CALLBACK() + +# define PROFILER_SET_JS_CONTEXT(cx) +# define PROFILER_CLEAR_JS_CONTEXT() + +// Function stubs for when MOZ_GECKO_PROFILER is not defined. + +// This won't be used, it's just there to allow the empty definition of +// `profiler_get_backtrace`. +struct ProfilerBacktrace {}; +using UniqueProfilerBacktrace = mozilla::UniquePtr<ProfilerBacktrace>; + +// Get/Capture-backtrace functions can return nullptr or false, the result +// should be fed to another empty macro or stub anyway. + +static inline UniqueProfilerBacktrace profiler_get_backtrace() { + return nullptr; +} + +// This won't be used, it's just there to allow the empty definitions of +// `profiler_capture_backtrace_into` and `profiler_capture_backtrace`. +struct ProfileChunkedBuffer {}; + +static inline bool profiler_capture_backtrace_into( + mozilla::ProfileChunkedBuffer& aChunkedBuffer, + mozilla::StackCaptureOptions aCaptureOptions) { + return false; +} +static inline mozilla::UniquePtr<mozilla::ProfileChunkedBuffer> +profiler_capture_backtrace() { + return nullptr; +} + +static inline void profiler_set_process_name( + const nsACString& aProcessName, const nsACString* aETLDplus1 = nullptr) {} + +static inline void profiler_received_exit_profile( + const nsACString& aExitProfile) {} + +static inline void profiler_register_page(uint64_t aTabID, + uint64_t aInnerWindowID, + const nsCString& aUrl, + uint64_t aEmbedderInnerWindowID, + bool aIsPrivateBrowsing) {} +static inline void profiler_unregister_page(uint64_t aRegisteredInnerWindowID) { +} + +static inline void GetProfilerEnvVarsForChildProcess( + std::function<void(const char* key, const char* value)>&& aSetEnv) {} + +static inline void profiler_record_wakeup_count( + const nsACString& aProcessType) {} + +#else // !MOZ_GECKO_PROFILER + +# include "js/ProfilingStack.h" +# include "mozilla/Assertions.h" +# include "mozilla/Atomics.h" +# include "mozilla/Attributes.h" +# include "mozilla/BaseProfilerRAIIMacro.h" +# include "mozilla/Maybe.h" +# include "mozilla/PowerOfTwo.h" +# include "mozilla/ThreadLocal.h" +# include "mozilla/TimeStamp.h" +# include "mozilla/UniquePtr.h" +# include "nscore.h" +# include "nsINamed.h" +# include "nsString.h" +# include "nsThreadUtils.h" + +# include <functional> +# include <stdint.h> + +class ProfilerBacktrace; +class ProfilerCodeAddressService; +struct JSContext; + +namespace mozilla { +class ProfileBufferControlledChunkManager; +class ProfileChunkedBuffer; +namespace baseprofiler { +class SpliceableJSONWriter; +} // namespace baseprofiler +} // namespace mozilla +class nsIURI; + +enum class ProfilerError { + IsInactive, + JsonGenerationFailed, +}; + +template <typename T> +using ProfilerResult = mozilla::Result<T, ProfilerError>; + +//--------------------------------------------------------------------------- +// Give information to the profiler +//--------------------------------------------------------------------------- + +// Register/unregister threads with the profiler. Both functions operate the +// same whether the profiler is active or inactive. +# define PROFILER_REGISTER_THREAD(name) \ + do { \ + char stackTop; \ + profiler_register_thread(name, &stackTop); \ + } while (0) +# define PROFILER_UNREGISTER_THREAD() profiler_unregister_thread() +ProfilingStack* profiler_register_thread(const char* name, void* guessStackTop); +void profiler_unregister_thread(); + +// Registers a DOM Window (the JS global `window`) with the profiler. Each +// Window _roughly_ corresponds to a single document loaded within a +// browsing context. Both the Window Id and Browser Id are recorded to allow +// correlating different Windows loaded within the same tab or frame element. +// +// We register pages for each navigations but we do not register +// history.pushState or history.replaceState since they correspond to the same +// Inner Window ID. 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. +// +// "aTabID" is the BrowserId of that document belongs to. +// That's used to determine the tab of that page. +// "aInnerWindowID" is the ID of the `window` global object of that +// document. +// "aUrl" is the URL of the page. +// "aEmbedderInnerWindowID" is the inner window id of embedder. It's used to +// determine sub documents of a page. +// "aIsPrivateBrowsing" is true if this browsing context happens in a +// private browsing context. +void profiler_register_page(uint64_t aTabID, uint64_t aInnerWindowID, + const nsCString& aUrl, + uint64_t aEmbedderInnerWindowID, + bool aIsPrivateBrowsing); +// Unregister page with the profiler. +// +// Take a Inner Window ID and unregister the page entry that has the same ID. +void profiler_unregister_page(uint64_t aRegisteredInnerWindowID); + +// Remove all registered and unregistered pages in the profiler. +void profiler_clear_all_pages(); + +class BaseProfilerCount; +void profiler_add_sampled_counter(BaseProfilerCount* aCounter); +void profiler_remove_sampled_counter(BaseProfilerCount* aCounter); + +// Register and unregister a thread within a scope. +# define AUTO_PROFILER_REGISTER_THREAD(name) \ + mozilla::AutoProfilerRegisterThread PROFILER_RAII(name) + +enum class SamplingState { + JustStopped, // Sampling loop has just stopped without sampling, between the + // callback registration and now. + SamplingPaused, // Profiler is active but sampling loop has gone through a + // pause. + NoStackSamplingCompleted, // A full sampling loop has completed in + // no-stack-sampling mode. + SamplingCompleted // A full sampling loop has completed. +}; + +using PostSamplingCallback = std::function<void(SamplingState)>; + +// Install a callback to be invoked at the end of the next sampling loop. +// - `false` if profiler is not active, `aCallback` will stay untouched. +// - `true` if `aCallback` was successfully moved-from into internal storage, +// and *will* be invoked at the end of the next sampling cycle. Note that this +// will happen on the Sampler thread, and will block further sampling, so +// please be mindful not to block for a long time (e.g., just dispatch a +// runnable to another thread.) Calling profiler functions from the callback +// is allowed. +[[nodiscard]] bool profiler_callback_after_sampling( + PostSamplingCallback&& aCallback); + +// Called by the JSRuntime's operation callback. This is used to start profiling +// on auxiliary threads. Operates the same whether the profiler is active or +// not. +# define PROFILER_JS_INTERRUPT_CALLBACK() profiler_js_interrupt_callback() +void profiler_js_interrupt_callback(); + +// Set and clear the current thread's JSContext. +# define PROFILER_SET_JS_CONTEXT(cx) profiler_set_js_context(cx) +# define PROFILER_CLEAR_JS_CONTEXT() profiler_clear_js_context() +void profiler_set_js_context(JSContext* aCx); +void profiler_clear_js_context(); + +//--------------------------------------------------------------------------- +// Get information from the profiler +//--------------------------------------------------------------------------- + +// Get the chunk manager used in the current profiling session, or null. +mozilla::ProfileBufferControlledChunkManager* +profiler_get_controlled_chunk_manager(); + +// The number of milliseconds since the process started. Operates the same +// whether the profiler is active or inactive. +double profiler_time(); + +// An object of this class is passed to profiler_suspend_and_sample_thread(). +// For each stack frame, one of the Collect methods will be called. +class ProfilerStackCollector { + public: + // Some collectors need to worry about possibly overwriting previous + // generations of data. If that's not an issue, this can return Nothing, + // which is the default behaviour. + virtual mozilla::Maybe<uint64_t> SamplePositionInBuffer() { + return mozilla::Nothing(); + } + virtual mozilla::Maybe<uint64_t> BufferRangeStart() { + return mozilla::Nothing(); + } + + // This method will be called once if the thread being suspended is the main + // thread. Default behaviour is to do nothing. + virtual void SetIsMainThread() {} + + // WARNING: The target thread is suspended when the Collect methods are + // called. Do not try to allocate or acquire any locks, or you could + // deadlock. The target thread will have resumed by the time this function + // returns. + + virtual void CollectNativeLeafAddr(void* aAddr) = 0; + + virtual void CollectJitReturnAddr(void* aAddr) = 0; + + virtual void CollectWasmFrame(const char* aLabel) = 0; + + virtual void CollectProfilingStackFrame( + const js::ProfilingStackFrame& aFrame) = 0; +}; + +// This method suspends the thread identified by aThreadId, samples its +// profiling stack, JS stack, and (optionally) native stack, passing the +// collected frames into aCollector. aFeatures dictates which compiler features +// are used. |Leaf| is the only relevant one. +// Use `ProfilerThreadId{}` (unspecified) to sample the current thread. +void profiler_suspend_and_sample_thread(ProfilerThreadId aThreadId, + uint32_t aFeatures, + ProfilerStackCollector& aCollector, + bool aSampleNative = true); + +struct ProfilerBacktraceDestructor { + void operator()(ProfilerBacktrace*); +}; + +using UniqueProfilerBacktrace = + mozilla::UniquePtr<ProfilerBacktrace, ProfilerBacktraceDestructor>; + +// Immediately capture the current thread's call stack, store it in the provided +// buffer (usually to avoid allocations if you can construct the buffer on the +// stack). Returns false if unsuccessful, or if the profiler is inactive. +bool profiler_capture_backtrace_into( + mozilla::ProfileChunkedBuffer& aChunkedBuffer, + mozilla::StackCaptureOptions aCaptureOptions); + +// Immediately capture the current thread's call stack, and return it in a +// ProfileChunkedBuffer (usually for later use in MarkerStack::TakeBacktrace()). +// May be null if unsuccessful, or if the profiler is inactive. +mozilla::UniquePtr<mozilla::ProfileChunkedBuffer> profiler_capture_backtrace(); + +// Immediately capture the current thread's call stack, and return it in a +// ProfilerBacktrace (usually for later use in marker function that take a +// ProfilerBacktrace). May be null if unsuccessful, or if the profiler is +// inactive. +UniqueProfilerBacktrace profiler_get_backtrace(); + +struct ProfilerStats { + unsigned n = 0; + double sum = 0; + double min = std::numeric_limits<double>::max(); + double max = 0; + void Count(double v) { + ++n; + sum += v; + if (v < min) { + min = v; + } + if (v > max) { + max = v; + } + } +}; + +struct ProfilerBufferInfo { + // Index of the oldest entry. + uint64_t mRangeStart; + // Index of the newest entry. + uint64_t mRangeEnd; + // Buffer capacity in number of 8-byte entries. + uint32_t mEntryCount; + // Sampling stats: Interval between successive samplings. + ProfilerStats mIntervalsUs; + // Sampling stats: Total sampling duration. (Split detail below.) + ProfilerStats mOverheadsUs; + // Sampling stats: Time to acquire the lock before sampling. + ProfilerStats mLockingsUs; + // Sampling stats: Time to discard expired data. + ProfilerStats mCleaningsUs; + // Sampling stats: Time to collect counter data. + ProfilerStats mCountersUs; + // Sampling stats: Time to sample thread stacks. + ProfilerStats mThreadsUs; +}; + +// Get information about the current buffer status. +// Returns Nothing() if the profiler is inactive. +// +// This information may be useful to a user-interface displaying the current +// status of the profiler, allowing the user to get a sense for how fast the +// buffer is being written to, and how much data is visible. +mozilla::Maybe<ProfilerBufferInfo> profiler_get_buffer_info(); + +// Record through glean how many times profiler_thread_wake has been +// called. +void profiler_record_wakeup_count(const nsACString& aProcessType); + +//--------------------------------------------------------------------------- +// Output profiles +//--------------------------------------------------------------------------- + +// Set a user-friendly process name, used in JSON stream. Allows an optional +// detailed name which may include private info (eTLD+1 in fission) +void profiler_set_process_name(const nsACString& aProcessName, + const nsACString* aETLDplus1 = nullptr); + +// Record an exit profile from a child process. +void profiler_received_exit_profile(const nsACString& aExitProfile); + +// Get the profile encoded as a JSON string. A no-op (returning nullptr) if the +// profiler is inactive. +// If aIsShuttingDown is true, the current time is included as the process +// shutdown time in the JSON's "meta" object. +mozilla::UniquePtr<char[]> profiler_get_profile(double aSinceTime = 0, + bool aIsShuttingDown = false); + +// Write the profile for this process (excluding subprocesses) into aWriter. +// Returns a failed result if the profiler is inactive. +ProfilerResult<mozilla::ProfileGenerationAdditionalInformation> +profiler_stream_json_for_this_process( + mozilla::baseprofiler::SpliceableJSONWriter& aWriter, double aSinceTime = 0, + bool aIsShuttingDown = false, + ProfilerCodeAddressService* aService = nullptr, + mozilla::ProgressLogger aProgressLogger = {}); + +// Get the profile and write it into a file. A no-op if the profile is +// inactive. +// +// This function is 'extern "C"' so that it is easily callable from a debugger +// in a build without debugging information (a workaround for +// http://llvm.org/bugs/show_bug.cgi?id=22211). +extern "C" { +void profiler_save_profile_to_file(const char* aFilename); +} + +//--------------------------------------------------------------------------- +// RAII classes +//--------------------------------------------------------------------------- + +namespace mozilla { + +// Convenience class to register and unregister a thread with the profiler. +// Needs to be the first object on the stack of the thread. +class MOZ_RAII AutoProfilerRegisterThread final { + public: + explicit AutoProfilerRegisterThread(const char* aName) { + profiler_register_thread(aName, this); + } + + ~AutoProfilerRegisterThread() { profiler_unregister_thread(); } + + private: + AutoProfilerRegisterThread(const AutoProfilerRegisterThread&) = delete; + AutoProfilerRegisterThread& operator=(const AutoProfilerRegisterThread&) = + delete; +}; + +// Get the MOZ_PROFILER_STARTUP* environment variables that should be +// supplied to a child process that is about to be launched, in order +// to make that child process start with the same profiler settings as +// in the current process. The given function is invoked once for +// each variable to be set. +void GetProfilerEnvVarsForChildProcess( + std::function<void(const char* key, const char* value)>&& aSetEnv); + +} // namespace mozilla + +#endif // !MOZ_GECKO_PROFILER + +#endif // GeckoProfiler_h |