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| -rw-r--r-- | mozglue/baseprofiler/public/BaseProfiler.h | 506 |
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diff --git a/mozglue/baseprofiler/public/BaseProfiler.h b/mozglue/baseprofiler/public/BaseProfiler.h new file mode 100644 index 0000000000..b66ef61126 --- /dev/null +++ b/mozglue/baseprofiler/public/BaseProfiler.h @@ -0,0 +1,506 @@ +/* -*- 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 BaseProfiler_h +#define BaseProfiler_h + +// This file is safe to include unconditionally, and only defines +// empty macros if MOZ_GECKO_PROFILER is not set. + +// These headers are also safe to include unconditionally, with empty macros if +// MOZ_GECKO_PROFILER is not set. +// 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 "mozilla/BaseProfilerCounts.h" +#include "mozilla/BaseProfilerLabels.h" +#include "mozilla/BaseProfilerMarkers.h" +#include "mozilla/BaseProfilerState.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 AUTO_BASE_PROFILER_INIT \ + ::mozilla::baseprofiler::profiler_init_main_thread_id() + +# define BASE_PROFILER_REGISTER_THREAD(name) +# define BASE_PROFILER_UNREGISTER_THREAD() +# define AUTO_BASE_PROFILER_REGISTER_THREAD(name) + +# define AUTO_BASE_PROFILER_THREAD_SLEEP +# define AUTO_BASE_PROFILER_THREAD_WAKE + +// Function stubs for when MOZ_GECKO_PROFILER is not defined. + +namespace mozilla { + +namespace baseprofiler { +// This won't be used, it's just there to allow the empty definition of +// `profiler_get_backtrace`. +struct ProfilerBacktrace {}; +using UniqueProfilerBacktrace = 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; +} + +static inline bool profiler_capture_backtrace_into( + ProfileChunkedBuffer& aChunkedBuffer, StackCaptureOptions aCaptureOptions) { + return false; +} + +static inline UniquePtr<ProfileChunkedBuffer> profiler_capture_backtrace() { + return nullptr; +} + +static inline void profiler_init(void* stackTop) {} + +static inline void profiler_shutdown() {} + +} // namespace baseprofiler +} // namespace mozilla + +#else // !MOZ_GECKO_PROFILER + +# include "BaseProfilingStack.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/TimeStamp.h" +# include "mozilla/UniquePtr.h" + +# include <functional> +# include <stdint.h> +# include <string> + +namespace mozilla { + +class MallocAllocPolicy; +class ProfileChunkedBuffer; +enum class StackCaptureOptions; +template <class T, size_t MinInlineCapacity, class AllocPolicy> +class Vector; + +namespace baseprofiler { + +class ProfilerBacktrace; +class SpliceableJSONWriter; + +//--------------------------------------------------------------------------- +// Start and stop the profiler +//--------------------------------------------------------------------------- + +static constexpr PowerOfTwo32 BASE_PROFILER_DEFAULT_ENTRIES = +# if !defined(GP_PLAT_arm_android) + MakePowerOfTwo32<16 * 1024 * 1024>(); // 16M entries = 128MiB +# else + MakePowerOfTwo32<4 * 1024 * 1024>(); // 4M entries = 32MiB +# endif + +// Startup profiling usually need to capture more data, especially on slow +// systems. +// Note: Keep in sync with GeckoThread.maybeStartGeckoProfiler: +// https://searchfox.org/mozilla-central/source/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoThread.java +static constexpr PowerOfTwo32 BASE_PROFILER_DEFAULT_STARTUP_ENTRIES = +# if !defined(GP_PLAT_arm_android) + mozilla::MakePowerOfTwo32<64 * 1024 * 1024>(); // 64M entries = 512MiB +# else + mozilla::MakePowerOfTwo32<16 * 1024 * 1024>(); // 16M entries = 128MiB +# endif + +// Note: Keep in sync with GeckoThread.maybeStartGeckoProfiler: +// https://searchfox.org/mozilla-central/source/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoThread.java +# define BASE_PROFILER_DEFAULT_INTERVAL 1 /* millisecond */ +# define BASE_PROFILER_MAX_INTERVAL 5000 /* milliseconds */ + +// Initialize the profiler. If MOZ_PROFILER_STARTUP is set the profiler will +// also be started. This call must happen before any other profiler calls +// (except profiler_start(), which will call profiler_init() if it hasn't +// already run). +MFBT_API void profiler_init(void* stackTop); + +# define AUTO_BASE_PROFILER_INIT \ + ::mozilla::baseprofiler::AutoProfilerInit PROFILER_RAII + +// Clean up the profiler module, stopping it if required. This function may +// also save a shutdown profile if requested. No profiler calls should happen +// after this point and all profiling stack labels should have been popped. +MFBT_API void profiler_shutdown(); + +// Start the profiler -- initializing it first if necessary -- with the +// selected options. Stops and restarts the profiler if it is already active. +// After starting the profiler is "active". The samples will be recorded in a +// circular buffer. +// "aCapacity" is the maximum number of 8-byte entries in the profiler's +// circular buffer. +// "aInterval" the sampling interval, measured in millseconds. +// "aFeatures" is the feature set. Features unsupported by this +// platform/configuration are ignored. +// "aFilters" is the list of thread filters. Threads that do not match any +// of the filters are not profiled. A filter matches a thread if +// (a) the thread name contains the filter as a case-insensitive +// substring, or +// (b) the filter is of the form "pid:<n>" where n is the process +// id of the process that the thread is running in. +// "aDuration" is the duration of entries in the profiler's circular buffer. +MFBT_API void profiler_start(PowerOfTwo32 aCapacity, double aInterval, + uint32_t aFeatures, const char** aFilters, + uint32_t aFilterCount, + const Maybe<double>& aDuration = Nothing()); + +// Stop the profiler and discard the profile without saving it. A no-op if the +// profiler is inactive. After stopping the profiler is "inactive". +MFBT_API void profiler_stop(); + +// If the profiler is inactive, start it. If it's already active, restart it if +// the requested settings differ from the current settings. Both the check and +// the state change are performed while the profiler state is locked. +// The only difference to profiler_start is that the current buffer contents are +// not discarded if the profiler is already running with the requested settings. +MFBT_API void profiler_ensure_started( + PowerOfTwo32 aCapacity, double aInterval, uint32_t aFeatures, + const char** aFilters, uint32_t aFilterCount, + const Maybe<double>& aDuration = Nothing()); + +//--------------------------------------------------------------------------- +// Control the profiler +//--------------------------------------------------------------------------- + +// Register/unregister threads with the profiler. Both functions operate the +// same whether the profiler is active or inactive. +# define BASE_PROFILER_REGISTER_THREAD(name) \ + do { \ + char stackTop; \ + ::mozilla::baseprofiler::profiler_register_thread(name, &stackTop); \ + } while (0) +# define BASE_PROFILER_UNREGISTER_THREAD() \ + ::mozilla::baseprofiler::profiler_unregister_thread() +MFBT_API ProfilingStack* profiler_register_thread(const char* name, + void* guessStackTop); +MFBT_API 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. +MFBT_API void profiler_register_page(uint64_t aTabD, uint64_t aInnerWindowID, + const std::string& aUrl, + uint64_t aEmbedderInnerWindowID); + +// Unregister page with the profiler. +// +// Take a Inner Window ID and unregister the page entry that has the same ID. +MFBT_API void profiler_unregister_page(uint64_t aRegisteredInnerWindowID); + +// Remove all registered and unregistered pages in the profiler. +void profiler_clear_all_pages(); + +class BaseProfilerCount; +MFBT_API void profiler_add_sampled_counter(BaseProfilerCount* aCounter); +MFBT_API void profiler_remove_sampled_counter(BaseProfilerCount* aCounter); + +// Register and unregister a thread within a scope. +# define AUTO_BASE_PROFILER_REGISTER_THREAD(name) \ + ::mozilla::baseprofiler::AutoProfilerRegisterThread PROFILER_RAII(name) + +// Pause and resume the profiler. No-ops if the profiler is inactive. While +// paused the profile will not take any samples and will not record any data +// into its buffers. The profiler remains fully initialized in this state. +// This feature will keep JavaScript profiling enabled, thus allowing toggling +// the profiler without invalidating the JIT. +MFBT_API void profiler_pause(); +MFBT_API void profiler_resume(); + +// Only pause and resume the periodic sampling loop, including stack sampling, +// counters, and profiling overheads. +MFBT_API void profiler_pause_sampling(); +MFBT_API void profiler_resume_sampling(); + +// These functions tell the profiler that a thread went to sleep so that we can +// avoid sampling it while it's sleeping. Calling profiler_thread_sleep() +// twice without an intervening profiler_thread_wake() is an error. All three +// functions operate the same whether the profiler is active or inactive. +MFBT_API void profiler_thread_sleep(); +MFBT_API void profiler_thread_wake(); + +// Mark a thread as asleep/awake within a scope. +# define AUTO_BASE_PROFILER_THREAD_SLEEP \ + ::mozilla::baseprofiler::AutoProfilerThreadSleep PROFILER_RAII +# define AUTO_BASE_PROFILER_THREAD_WAKE \ + ::mozilla::baseprofiler::AutoProfilerThreadWake PROFILER_RAII + +//--------------------------------------------------------------------------- +// Get information from the profiler +//--------------------------------------------------------------------------- + +// Get the params used to start the profiler. Returns 0 and an empty vector +// (via outparams) if the profile is inactive. It's possible that the features +// returned may be slightly different to those requested due to required +// adjustments. +MFBT_API void profiler_get_start_params( + int* aEntrySize, Maybe<double>* aDuration, double* aInterval, + uint32_t* aFeatures, Vector<const char*, 0, MallocAllocPolicy>* aFilters); + +// The number of milliseconds since the process started. Operates the same +// whether the profiler is active or inactive. +MFBT_API 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 Maybe<uint64_t> SamplePositionInBuffer() { return Nothing(); } + virtual Maybe<uint64_t> BufferRangeStart() { return 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 CollectProfilingStackFrame( + const 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 `aThreadId`=0 to sample the current thread. +MFBT_API void profiler_suspend_and_sample_thread( + int aThreadId, uint32_t aFeatures, ProfilerStackCollector& aCollector, + bool aSampleNative = true); + +struct ProfilerBacktraceDestructor { + MFBT_API void operator()(ProfilerBacktrace*); +}; + +using UniqueProfilerBacktrace = + 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, if the profiler is inactive, or if +// aCaptureOptions is NoStack. +MFBT_API bool profiler_capture_backtrace_into( + ProfileChunkedBuffer& aChunkedBuffer, 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. +MFBT_API UniquePtr<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. +MFBT_API 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 (us) between successive samplings. + ProfilerStats mIntervalsUs; + // Sampling stats: Total duration (us) of each sampling. (Split detail below.) + ProfilerStats mOverheadsUs; + // Sampling stats: Time (us) to acquire the lock before sampling. + ProfilerStats mLockingsUs; + // Sampling stats: Time (us) to discard expired data. + ProfilerStats mCleaningsUs; + // Sampling stats: Time (us) to collect counter data. + ProfilerStats mCountersUs; + // Sampling stats: Time (us) 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. +MFBT_API Maybe<ProfilerBufferInfo> profiler_get_buffer_info(); + +} // namespace baseprofiler +} // namespace mozilla + +namespace mozilla { +namespace baseprofiler { + +//--------------------------------------------------------------------------- +// Put profiling data into the profiler (markers) +//--------------------------------------------------------------------------- + +MFBT_API void profiler_add_js_marker(const char* aMarkerName, + const char* aMarkerText); + +//--------------------------------------------------------------------------- +// Output profiles +//--------------------------------------------------------------------------- + +// Set a user-friendly process name, used in JSON stream. +MFBT_API void profiler_set_process_name(const std::string& aProcessName, + const std::string* aETLDplus1); + +// 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. +MFBT_API UniquePtr<char[]> profiler_get_profile(double aSinceTime = 0, + bool aIsShuttingDown = false, + bool aOnlyThreads = false); + +// Write the profile for this process (excluding subprocesses) into aWriter. +// Returns false if the profiler is inactive. +MFBT_API bool profiler_stream_json_for_this_process( + SpliceableJSONWriter& aWriter, double aSinceTime = 0, + bool aIsShuttingDown = false, bool aOnlyThreads = false); + +// Get the profile and write it into a file. A no-op if the profile is +// inactive. +// Prefixed with "base" to avoid clashing with Gecko Profiler's extern "C" +// profiler_save_profile_to_file when called from debugger. +MFBT_API void baseprofiler_save_profile_to_file(const char* aFilename); + +//--------------------------------------------------------------------------- +// RAII classes +//--------------------------------------------------------------------------- + +class MOZ_RAII AutoProfilerInit { + public: + explicit AutoProfilerInit() { profiler_init(this); } + + ~AutoProfilerInit() { profiler_shutdown(); } + + private: +}; + +// 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; +}; + +class MOZ_RAII AutoProfilerThreadSleep { + public: + explicit AutoProfilerThreadSleep() { profiler_thread_sleep(); } + + ~AutoProfilerThreadSleep() { profiler_thread_wake(); } + + private: +}; + +// Temporarily wake up the profiling of a thread while servicing events such as +// Asynchronous Procedure Calls (APCs). +class MOZ_RAII AutoProfilerThreadWake { + public: + explicit AutoProfilerThreadWake() + : mIssuedWake(profiler_thread_is_sleeping()) { + if (mIssuedWake) { + profiler_thread_wake(); + } + } + + ~AutoProfilerThreadWake() { + if (mIssuedWake) { + MOZ_ASSERT(!profiler_thread_is_sleeping()); + profiler_thread_sleep(); + } + } + + private: + bool mIssuedWake; +}; + +// 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. +MFBT_API void GetProfilerEnvVarsForChildProcess( + std::function<void(const char* key, const char* value)>&& aSetEnv); + +} // namespace baseprofiler +} // namespace mozilla + +#endif // !MOZ_GECKO_PROFILER + +#endif // BaseProfiler_h |