tracing: remove sampling state profiler

base/trace_event/trace_sampling_thread.cc

Index: base/trace_event/trace_sampling_thread.cc
diff --git a/base/trace_event/trace_sampling_thread.cc b/base/trace_event/trace_sampling_thread.cc
deleted file mode 100644
index 5a0d2f8a024e12f3a23fbc6673bba1bbaedb323a..0000000000000000000000000000000000000000
--- a/base/trace_event/trace_sampling_thread.cc
+++ /dev/null
@@ -1,107 +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 <stddef.h>
-
-#include "base/trace_event/trace_event.h"
-#include "base/trace_event/trace_event_impl.h"
-#include "base/trace_event/trace_log.h"
-#include "base/trace_event/trace_sampling_thread.h"
-
-namespace base {
-namespace trace_event {
-
-class TraceBucketData {
- public:
-  TraceBucketData(base::subtle::AtomicWord* bucket,
-                  const char* name,
-                  TraceSampleCallback callback);
-  ~TraceBucketData();
-
-  TRACE_EVENT_API_ATOMIC_WORD* bucket;
-  const char* bucket_name;
-  TraceSampleCallback callback;
-};
-
-TraceSamplingThread::TraceSamplingThread()
-    : thread_running_(false),
-      waitable_event_for_testing_(WaitableEvent::ResetPolicy::AUTOMATIC,
-                                  WaitableEvent::InitialState::NOT_SIGNALED) {}
-
-TraceSamplingThread::~TraceSamplingThread() {}
-
-void TraceSamplingThread::ThreadMain() {
-  PlatformThread::SetName("Sampling Thread");
-  thread_running_ = true;
-  const int kSamplingFrequencyMicroseconds = 1000;
-  while (!cancellation_flag_.IsSet()) {
-    PlatformThread::Sleep(
-        TimeDelta::FromMicroseconds(kSamplingFrequencyMicroseconds));
-    GetSamples();
-    waitable_event_for_testing_.Signal();
-  }
-}
-
-// static
-void TraceSamplingThread::DefaultSamplingCallback(
-    TraceBucketData* bucket_data) {
-  TRACE_EVENT_API_ATOMIC_WORD category_and_name =
-      TRACE_EVENT_API_ATOMIC_LOAD(*bucket_data->bucket);
-  if (!category_and_name)
-    return;
-  const char* const combined =
-      reinterpret_cast<const char* const>(category_and_name);
-  const char* category_group;
-  const char* name;
-  ExtractCategoryAndName(combined, &category_group, &name);
-  TRACE_EVENT_API_ADD_TRACE_EVENT(
-      TRACE_EVENT_PHASE_SAMPLE,
-      TraceLog::GetCategoryGroupEnabled(category_group), name,
-      trace_event_internal::kGlobalScope, trace_event_internal::kNoId, 0,
-      NULL, NULL, NULL, NULL, 0);
-}
-
-void TraceSamplingThread::GetSamples() {
-  for (size_t i = 0; i < sample_buckets_.size(); ++i) {
-    TraceBucketData* bucket_data = &sample_buckets_[i];
-    bucket_data->callback.Run(bucket_data);
-  }
-}
-
-void TraceSamplingThread::RegisterSampleBucket(
-    TRACE_EVENT_API_ATOMIC_WORD* bucket,
-    const char* const name,
-    TraceSampleCallback callback) {
-  // Access to sample_buckets_ doesn't cause races with the sampling thread
-  // that uses the sample_buckets_, because it is guaranteed that
-  // RegisterSampleBucket is called before the sampling thread is created.
-  DCHECK(!thread_running_);
-  sample_buckets_.push_back(TraceBucketData(bucket, name, callback));
-}
-
-// static
-void TraceSamplingThread::ExtractCategoryAndName(const char* combined,
-                                                 const char** category,
-                                                 const char** name) {
-  *category = combined;
-  *name = &combined[strlen(combined) + 1];
-}
-
-void TraceSamplingThread::Stop() {
-  cancellation_flag_.Set();
-}
-
-void TraceSamplingThread::WaitSamplingEventForTesting() {
-  waitable_event_for_testing_.Wait();
-}
-
-TraceBucketData::TraceBucketData(base::subtle::AtomicWord* bucket,
-                                 const char* name,
-                                 TraceSampleCallback callback)
-    : bucket(bucket), bucket_name(name), callback(callback) {}
-
-TraceBucketData::~TraceBucketData() {}
-
-}  // namespace trace_event
-}  // namespace base