Revert of Temporary commit to evaluate perf impact of prototype CPU profiler

base/profiler/cpu_profiler.cc

Index: base/profiler/cpu_profiler.cc
diff --git a/base/profiler/cpu_profiler.cc b/base/profiler/cpu_profiler.cc
deleted file mode 100644
index 48014ce4195043911fee1d32425bbd7b2c8e0acb..0000000000000000000000000000000000000000
--- a/base/profiler/cpu_profiler.cc
+++ /dev/null
@@ -1,174 +0,0 @@
-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "base/profiler/cpu_profiler.h"
-
-#include <stddef.h>
-
-#include "base/debug/stack_trace.h"
-#include "base/metrics/field_trial.h"
-#include "base/strings/string_number_conversions.h"
-#include "base/threading/thread_id_name_manager.h"
-#include "base/time/time.h"
-#include "base/timer/elapsed_timer.h"
-
-namespace base {
-
-namespace {
-
-const char kMode[] = "Mode";
-const char kInitialDelay[] = "InitialDelay";
-const char kNumberOfBursts[] = "NumberOfBursts";
-const char kBurstIdleTime[] = "IdleTime";
-const char kNumberOfSamples[] = "NumberOfSamples";
-const char kSamplingSleepTime[] = "SamplingSleepTime";
-
-}  // namespace
-
-class CpuProfiler::SamplingThread : public PlatformThread::Delegate {
- public:
-  SamplingThread(CpuProfiler* cpu_profiler);
-  ~SamplingThread() override;
-
-  // Implementation of PlatformThread::Delegate:
-  void ThreadMain() override;
-
-  void Stop();
-
-  void GetSamples();
-
- private:
-  CpuProfiler* cpu_profiler_;
-
-  bool thread_running_;
-
-  base::WaitableEvent waitable_event_;
-
-  DISALLOW_COPY_AND_ASSIGN(SamplingThread);
-};
-
-CpuProfiler::SamplingThread::SamplingThread(CpuProfiler* cpu_profiler)
-    : cpu_profiler_(cpu_profiler),
-      thread_running_(false),
-      waitable_event_(false, false) {
-}
-
-CpuProfiler::SamplingThread::~SamplingThread() {}
-
-void CpuProfiler::SamplingThread::ThreadMain() {
-  PlatformThread::SetName("Chrome_CPUProfilerThread");
-  thread_running_ = true;
-
-  if (cpu_profiler_->GetStringParam(kMode) == "bursts") {
-    int64 initial_delay = cpu_profiler_->GetInt64Param(kInitialDelay);
-    int number_of_bursts = cpu_profiler_->GetIntParam(kNumberOfBursts);
-    int64 burst_idle_time = cpu_profiler_->GetInt64Param(kBurstIdleTime);
-    int number_of_samples = cpu_profiler_->GetIntParam(kNumberOfSamples);
-    int64 sampling_sleep_time =
-        cpu_profiler_->GetInt64Param(kSamplingSleepTime);
-
-    if (waitable_event_.TimedWait(TimeDelta::FromMicroseconds(initial_delay)))
-      return;
-    for (int i = 0; i < number_of_bursts; ++i) {
-      int64 delta = 0;
-      for (int j = 0; ; ++j) {
-        base::ElapsedTimer time;
-        GetSamples();
-        delta = time.Elapsed().InMicroseconds();
-        if (j == (number_of_samples - 1))
-          break;
-        if (delta < sampling_sleep_time) {
-          if (waitable_event_.TimedWait(
-              TimeDelta::FromMicroseconds(sampling_sleep_time - delta)))
-            return;
-        } else {
-          if (waitable_event_.TimedWait(
-              TimeDelta::FromMicroseconds(sampling_sleep_time)))
-            return;
-        }
-      }
-      if (waitable_event_.TimedWait(
-          TimeDelta::FromMicroseconds(burst_idle_time - delta)))
-        return;
-    }
-  }
-}
-
-void CpuProfiler::SamplingThread::Stop() {
-  waitable_event_.Signal();
-}
-
-void CpuProfiler::SamplingThread::GetSamples() {
-  cpu_profiler_->OnTimer();
-}
-
-void CpuProfiler::SamplingThreadDeleter::operator()(
-    SamplingThread* thread) const {
-  delete thread;
-}
-
-void CpuProfiler::Initialize(const std::map<std::string, std::string>* params) {
-  if (!CpuProfiler::IsPlatformSupported())
-    return;
-
-  std::map<std::string, std::string> default_params;
-  default_params[kMode] = "bursts";
-  default_params[kInitialDelay] = "0"; // 0 sec
-  default_params[kNumberOfBursts] = "1";
-  default_params[kBurstIdleTime] = "10000000"; // 10 sec
-  default_params[kNumberOfSamples] = "300";
-  default_params[kSamplingSleepTime] = "100000"; // 100 ms
-
-  if (!params)
-    SetParams(default_params);
-  else
-    SetParams(*params);
-
-  sampling_thread_.reset(new SamplingThread(this));
-  if (!PlatformThread::Create(0, sampling_thread_.get(),
-                              &sampling_thread_handle_)) {
-    LOG(ERROR) << "failed to create thread";
-  }
-}
-
-void CpuProfiler::Stop() {
-  if (sampling_thread_)
-    sampling_thread_->Stop();
-}
-
-
-std::string CpuProfiler::GetStringParam(const std::string& key) const{
-  const auto entry = params_.find(key);
-  if (entry != params_.end()) {
-    return entry->second;
-  }
-  return "";
-}
-
-int CpuProfiler::GetIntParam(const std::string& key) const {
-  const auto entry = params_.find(key);
-  if (entry != params_.end()) {
-    int output;
-    if (base::StringToInt(entry->second, &output))
-      return output;
-  }
-  return 0;
-}
-
-int64 CpuProfiler::GetInt64Param(const std::string& key) const {
-  const auto entry = params_.find(key);
-  if (entry != params_.end()) {
-    int64 output;
-    if (base::StringToInt64(entry->second, &output))
-      return output;
-  }
-  return 0;
-}
-
-void CpuProfiler::SetParams(
-    const std::map<std::string, std::string>& params) {
-  params_ = params;
-}
-
-}  // namespace base