// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Adapted from chrome/common/profiler/thread_profiler.h
// TODO(crbug.com/40778431): remove this once //chrome/common/profiler is moved
// to components/profiler.
#ifndef IOS_CHROME_BROWSER_WEB_MODEL_IOS_THREAD_PROFILER_H_
#define IOS_CHROME_BROWSER_WEB_MODEL_IOS_THREAD_PROFILER_H_
#include <memory>
#include "base/functional/callback.h"
#include "base/memory/weak_ptr.h"
#include "base/profiler/process_type.h"
#include "base/profiler/stack_sampling_profiler.h"
#include "base/task/single_thread_task_runner.h"
#include "base/threading/thread.h"
#include "base/threading/thread_checker.h"
#include "base/time/time.h"
#include "components/metrics/public/mojom/call_stack_profile_collector.mojom.h"
#include "mojo/public/cpp/bindings/pending_remote.h"
#include "third_party/metrics_proto/sampled_profile.pb.h"
// PeriodicSamplingScheduler repeatedly schedules periodic sampling of the
// thread through calls to GetTimeToNextCollection(). This class is exposed
// to allow testing.
class PeriodicSamplingScheduler {
public:
PeriodicSamplingScheduler(base::TimeDelta sampling_duration,
double fraction_of_execution_time_to_sample,
base::TimeTicks start_time);
virtual ~PeriodicSamplingScheduler();
PeriodicSamplingScheduler(const PeriodicSamplingScheduler&) = delete;
PeriodicSamplingScheduler& operator=(const PeriodicSamplingScheduler&) =
delete;
// Returns the amount of time between now and the next collection.
base::TimeDelta GetTimeToNextCollection();
protected:
// Virtual to provide seams for test use.
virtual double RandDouble() const;
virtual base::TimeTicks Now() const;
private:
const base::TimeDelta period_duration_;
const base::TimeDelta sampling_duration_;
base::TimeTicks period_start_time_;
};
// IOSThreadProfiler performs startup and periodic profiling of Chrome
// threads.
class IOSThreadProfiler {
public:
~IOSThreadProfiler();
IOSThreadProfiler(const IOSThreadProfiler&) = delete;
IOSThreadProfiler& operator=(const IOSThreadProfiler&) = delete;
// Creates a profiler for a main thread and immediately starts it. This
// function should only be used when profiling the main thread of a
// process. The returned profiler must be destroyed prior to thread exit to
// stop the profiling.
//
// SetMainThreadTaskRunner() should be called after the message loop has been
// started on the thread. It is the caller's responsibility to ensure that
// the instance returned by this function is still alive when the static API
// SetMainThreadTaskRunner() is used. The latter is static to support Chrome's
// set up where the IOSThreadProfiler is created in chrome/app which cannot be
// easily accessed from chrome_browser_main.cc which sets the task runner.
static std::unique_ptr<IOSThreadProfiler> CreateAndStartOnMainThread();
// Sets the task runner when profiling on the main thread. This occurs in a
// separate call from CreateAndStartOnMainThread so that startup profiling can
// occur prior to message loop start. The task runner is associated with the
// instance returned by CreateAndStartOnMainThread(), which must be alive when
// this is called.
static void SetMainThreadTaskRunner(
scoped_refptr<base::SingleThreadTaskRunner> task_runner);
// Get the stack sampling params to use.
static base::StackSamplingProfiler::SamplingParams GetSamplingParams();
// Creates a profiler for a child thread and immediately starts it. This
// should be called from a task posted on the child thread immediately after
// thread start. The thread will be profiled until exit.
static void StartOnChildThread(base::ProfilerThreadType thread);
// Sets the callback to use for reporting browser process profiles. This
// indirection is required to avoid a dependency on unnecessary metrics code
// in child processes.
static void SetBrowserProcessReceiverCallback(
const base::RepeatingCallback<void(base::TimeTicks,
metrics::SampledProfile)>& callback);
// This function must be called within child processes to supply the Service
// Manager's connector, to bind the interface through which a profile is sent
// back to the browser process.
//
// Note that the metrics::CallStackProfileCollector interface also must be
// exposed to the child process, and metrics::mojom::CallStackProfileCollector
// declared in chrome_content_browser_manifest_overlay.json, for the binding
// to succeed.
static void SetCollectorForChildProcess(
mojo::PendingRemote<metrics::mojom::CallStackProfileCollector> collector);
private:
class WorkIdRecorder;
// Creates the profiler. The task runner will be supplied for child threads
// but not for main threads.
IOSThreadProfiler(
base::ProfilerThreadType thread,
scoped_refptr<base::SingleThreadTaskRunner> owning_thread_task_runner =
scoped_refptr<base::SingleThreadTaskRunner>());
// Posts a task on `owning_thread_task_runner` to start the next periodic
// sampling collection on the completion of the previous collection.
static void OnPeriodicCollectionCompleted(
scoped_refptr<base::SingleThreadTaskRunner> owning_thread_task_runner,
base::WeakPtr<IOSThreadProfiler> thread_profiler);
// Sets the task runner when profiling on the main thread. This occurs in a
// separate call from CreateAndStartOnMainThread so that startup profiling can
// occur prior to message loop start.
void SetMainThreadTaskRunnerImpl(
scoped_refptr<base::SingleThreadTaskRunner> task_runner);
// Posts a delayed task to start the next periodic sampling collection.
void ScheduleNextPeriodicCollection();
// Creates a new periodic profiler and initiates a collection with it.
void StartPeriodicSamplingCollection();
const base::ProfilerProcessType process_;
const base::ProfilerThreadType thread_;
scoped_refptr<base::SingleThreadTaskRunner> owning_thread_task_runner_;
std::unique_ptr<WorkIdRecorder> work_id_recorder_;
std::unique_ptr<base::StackSamplingProfiler> startup_profiler_;
std::unique_ptr<base::StackSamplingProfiler> periodic_profiler_;
std::unique_ptr<PeriodicSamplingScheduler> periodic_sampling_scheduler_;
THREAD_CHECKER(thread_checker_);
base::WeakPtrFactory<IOSThreadProfiler> weak_factory_{this};
};
#endif // IOS_CHROME_BROWSER_WEB_MODEL_IOS_THREAD_PROFILER_H_