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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 */
#ifndef ProfiledThreadData_h
#define ProfiledThreadData_h
#include "BaseProfilingStack.h"
#include "platform.h"
#include "ProfileBufferEntry.h"
#include "ThreadInfo.h"
#include "mozilla/RefPtr.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/UniquePtr.h"
#include <string>
namespace mozilla {
namespace baseprofiler {
class ProfileBuffer;
// This class contains information about a thread that is only relevant while
// the profiler is running, for any threads (both alive and dead) whose thread
// name matches the "thread filter" in the current profiler run.
// ProfiledThreadData objects may be kept alive even after the thread is
// unregistered, as long as there is still data for that thread in the profiler
// buffer.
// Accesses to this class are protected by the profiler state lock.
// Created as soon as the following are true for the thread:
// - The profiler is running, and
// - the thread matches the profiler's thread filter, and
// - the thread is registered with the profiler.
// So it gets created in response to either (1) the profiler being started (for
// an existing registered thread) or (2) the thread being registered (if the
// profiler is already running).
// The thread may be unregistered during the lifetime of ProfiledThreadData.
// If that happens, NotifyUnregistered() is called.
// This class is the right place to store buffer positions. Profiler buffer
// positions become invalid if the profiler buffer is destroyed, which happens
// when the profiler is stopped.
class ProfiledThreadData final {
explicit ProfiledThreadData(ThreadInfo* aThreadInfo);
void NotifyUnregistered(uint64_t aBufferPosition) {
mLastSample = Nothing();
"JSContext should have been cleared before the thread was "
mUnregisterTime = TimeStamp::Now();
mBufferPositionWhenUnregistered = Some(aBufferPosition);
Maybe<uint64_t> BufferPositionWhenUnregistered() {
return mBufferPositionWhenUnregistered;
Maybe<uint64_t>& LastSample() { return mLastSample; }
void StreamJSON(const ProfileBuffer& aBuffer, SpliceableJSONWriter& aWriter,
const std::string& aProcessName,
const std::string& aETLDplus1,
const TimeStamp& aProcessStartTime, double aSinceTime);
const RefPtr<ThreadInfo> Info() const { return mThreadInfo; }
void NotifyReceivedJSContext(uint64_t aCurrentBufferPosition) {
mBufferPositionWhenReceivedJSContext = Some(aCurrentBufferPosition);
// Group A:
// The following fields are interesting for the entire lifetime of a
// ProfiledThreadData object.
// This thread's thread info.
const RefPtr<ThreadInfo> mThreadInfo;
// Group B:
// The following fields are only used while this thread is alive and
// registered. They become Nothing() once the thread is unregistered.
// When sampling, this holds the position in ActivePS::mBuffer of the most
// recent sample for this thread, or Nothing() if there is no sample for this
// thread in the buffer.
Maybe<uint64_t> mLastSample;
// Only non-Nothing() if the thread currently has a JSContext.
Maybe<uint64_t> mBufferPositionWhenReceivedJSContext;
// Group C:
// The following fields are only used once this thread has been unregistered.
Maybe<uint64_t> mBufferPositionWhenUnregistered;
TimeStamp mUnregisterTime;
// Stream all samples and markers from aBuffer with the given aThreadId (or 0
// for everything, which is assumed to be a single backtrace sample.)
// Returns the thread id of the output sample(s), or 0 if none was present.
BaseProfilerThreadId StreamSamplesAndMarkers(
const char* aName, BaseProfilerThreadId aThreadId,
const ProfileBuffer& aBuffer, SpliceableJSONWriter& aWriter,
const std::string& aProcessName, const std::string& aETLDplus1,
const TimeStamp& aProcessStartTime, const TimeStamp& aRegisterTime,
const TimeStamp& aUnregisterTime, double aSinceTime,
UniqueStacks& aUniqueStacks);
} // namespace baseprofiler
} // namespace mozilla
#endif // ProfiledThreadData_h