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/* -*- 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 */
// APIs that control the lifetime of the profiler: Initialization, start, pause,
// resume, stop, and shutdown.
#ifndef ProfilerControl_h
#define ProfilerControl_h
#include "mozilla/BaseProfilerRAIIMacro.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.
enum class IsFastShutdown {
// 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_PROFILER_INIT ::profiler_init_main_thread_id()
// Function stubs for when MOZ_GECKO_PROFILER is not defined.
static inline void profiler_init(void* stackTop) {}
static inline void profiler_shutdown(
IsFastShutdown aIsFastShutdown = IsFastShutdown::No) {}
static inline void profiler_lookup_download_directory() {}
# include "BaseProfiler.h"
# include "mozilla/Attributes.h"
# include "mozilla/Maybe.h"
# include "mozilla/MozPromise.h"
# include "mozilla/PowerOfTwo.h"
# include "mozilla/Vector.h"
// Start and stop the profiler
static constexpr mozilla::PowerOfTwo32 PROFILER_DEFAULT_ENTRIES =
static constexpr mozilla::PowerOfTwo32 PROFILER_DEFAULT_STARTUP_ENTRIES =
static constexpr mozilla::PowerOfTwo32 PROFILER_DEFAULT_SIGHANDLE_ENTRIES =
mozilla::MakePowerOfTwo32<64 * 1024 * 1024>(); // 64M entries = 512MiB
// 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).
void profiler_init(void* stackTop);
void profiler_init_threadmanager();
// Call this as early as possible
# define AUTO_PROFILER_INIT mozilla::AutoProfilerInit PROFILER_RAII
// Call this after the nsThreadManager is Init()ed
# define AUTO_PROFILER_INIT2 mozilla::AutoProfilerInit2 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.
void profiler_shutdown(IsFastShutdown aIsFastShutdown = IsFastShutdown::No);
// 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-bytes 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.
// "aActiveTabID" BrowserId 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.
// "aDuration" is the duration of entries in the profiler's circular buffer.
// Returns as soon as this process' profiler has started, the returned promise
// gets resolved when profilers in sub-processes (if any) have started.
RefPtr<mozilla::GenericPromise> profiler_start(
mozilla::PowerOfTwo32 aCapacity, double aInterval, uint32_t aFeatures,
const char** aFilters, uint32_t aFilterCount, uint64_t aActiveTabID,
const mozilla::Maybe<double>& aDuration = mozilla::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".
// Returns as soon as this process' profiler has stopped, the returned promise
// gets resolved when profilers in sub-processes (if any) have stopped.
RefPtr<mozilla::GenericPromise> 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.
void profiler_ensure_started(
mozilla::PowerOfTwo32 aCapacity, double aInterval, uint32_t aFeatures,
const char** aFilters, uint32_t aFilterCount, uint64_t aActiveTabID,
const mozilla::Maybe<double>& aDuration = mozilla::Nothing());
// Tell the profiler to look up the download directory for writing profiles.
// With some features, such as signal control, we need to know the location of
// a directory where we can save profiles to disk. Because we start the
// profiler before we start the directory service, we can't access the
// download directory at profiler startup. Similarly, when we need to get the
// directory, we often can't, as we're running in non-main-thread contexts
// that don't have access to the directory service. This function gives us a
// third option, by giving us a hook to look for the download directory when
// the time is right. This might be triggered internally (e.g. when we start
// profiling), or externally, e.g. after the directory service is initialised.
void profiler_lookup_download_directory();
// Control the profiler
// 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.
// Timeline markers will still be stored. This feature will keep JavaScript
// profiling enabled, thus allowing toggling the profiler without invalidating
// the JIT.
// Returns as soon as this process' profiler has paused/resumed, the returned
// promise gets resolved when profilers in sub-processes (if any) have
// paused/resumed.
RefPtr<mozilla::GenericPromise> profiler_pause();
RefPtr<mozilla::GenericPromise> profiler_resume();
// Only pause and resume the periodic sampling loop, including stack sampling,
// counters, and profiling overheads.
// Returns as soon as this process' profiler has paused/resumed sampling, the
// returned promise gets resolved when profilers in sub-processes (if any) have
// paused/resumed sampling.
RefPtr<mozilla::GenericPromise> profiler_pause_sampling();
RefPtr<mozilla::GenericPromise> profiler_resume_sampling();
// 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.
void profiler_get_start_params(
int* aEntrySize, mozilla::Maybe<double>* aDuration, double* aInterval,
uint32_t* aFeatures,
mozilla::Vector<const char*, 0, mozilla::MallocAllocPolicy>* aFilters,
uint64_t* aActiveTabID);
// RAII classes
namespace mozilla {
class MOZ_RAII AutoProfilerInit {
explicit AutoProfilerInit() { profiler_init(this); }
~AutoProfilerInit() { profiler_shutdown(); }
class MOZ_RAII AutoProfilerInit2 {
explicit AutoProfilerInit2() { profiler_init_threadmanager(); }
} // namespace mozilla
#endif // ProfilerControl_h