1 files changed, 9 insertions, 37 deletions

diff --git a/chromium/base/task/thread_pool/task_tracker.h b/chromium/base/task/thread_pool/task_tracker.h
index bb5296b7da1..59f0726b8eb 100644
--- a/chromium/base/task/thread_pool/task_tracker.h
+++ b/chromium/base/task/thread_pool/task_tracker.h
@@ -31,7 +31,6 @@
 namespace base {
 
 class ConditionVariable;
-class HistogramBase;
 
 namespace internal {
 
@@ -54,7 +53,8 @@ enum class CanRunPolicy {
 // and records metrics and trace events. This class is thread-safe.
 class BASE_EXPORT TaskTracker {
  public:
-  // |histogram_label| is used as a suffix for histograms, it must not be empty.
+  // |histogram_label| is used to label histograms. No histograms are recorded
+  // if it is empty.
   TaskTracker(StringPiece histogram_label);
 
   virtual ~TaskTracker();
@@ -131,26 +131,15 @@ class BASE_EXPORT TaskTracker {
   // no tasks are blocking shutdown).
   bool IsShutdownComplete() const;
 
-  enum class LatencyHistogramType {
-    // Records the latency of each individual task posted through TaskTracker.
-    TASK_LATENCY,
-    // Records the latency of heartbeat tasks which are independent of current
-    // workload. These avoid a bias towards TASK_LATENCY reporting that high-
-    // priority tasks are "slower" than regular tasks because high-priority
-    // tasks tend to be correlated with heavy workloads.
-    HEARTBEAT_LATENCY,
-  };
-
   // Records two histograms
   // 1. ThreadPool.[label].HeartbeatLatencyMicroseconds.[suffix]:
   //    Now() - posted_time
   // 2. ThreadPool.[label].NumTasksRunWhileQueuing.[suffix]:
   //    GetNumTasksRun() - num_tasks_run_when_posted.
   // [label] is the histogram label provided to the constructor.
-  // [suffix] is derived from |task_priority| and |may_block|.
+  // [suffix] is derived from |task_priority|.
   void RecordHeartbeatLatencyAndTasksRunWhileQueuingHistograms(
       TaskPriority task_priority,
-      bool may_block,
       TimeTicks posted_time,
       int num_tasks_run_when_posted) const;
 
@@ -213,10 +202,9 @@ class BASE_EXPORT TaskTracker {
   // manner.
   void CallFlushCallbackForTesting();
 
-  // Records |Now() - posted_time| to the appropriate |latency_histogram_type|
-  // based on |task_traits|.
-  void RecordLatencyHistogram(LatencyHistogramType latency_histogram_type,
-                              TaskTraits task_traits,
+  // Records |Now() - posted_time| to the
+  // ThreadPool.TaskLatencyMicroseconds.[label].[priority] histogram.
+  void RecordLatencyHistogram(TaskPriority priority,
                               TimeTicks posted_time) const;
 
   void IncrementNumTasksRun();
@@ -230,6 +218,9 @@ class BASE_EXPORT TaskTracker {
 
   TaskAnnotator task_annotator_;
 
+  // Suffix for histograms recorded by this TaskTracker.
+  const std::string histogram_label_;
+
   // Indicates whether logging information about TaskPriority::BEST_EFFORT tasks
   // was enabled with a command line switch.
   const bool has_log_best_effort_tasks_switch_;
@@ -277,25 +268,6 @@ class BASE_EXPORT TaskTracker {
   // a task queued to histogram.
   std::atomic_int num_tasks_run_{0};
 
-  // ThreadPool.TaskLatencyMicroseconds.*,
-  // ThreadPool.HeartbeatLatencyMicroseconds.*, and
-  // ThreadPool.NumTasksRunWhileQueuing.* histograms. The first index is
-  // a TaskPriority. The second index is 0 for non-blocking tasks, 1 for
-  // blocking tasks. Intentionally leaked.
-  // TODO(scheduler-dev): Consider using STATIC_HISTOGRAM_POINTER_GROUP for
-  // these.
-  using TaskPriorityType = std::underlying_type<TaskPriority>::type;
-  static constexpr TaskPriorityType kNumTaskPriorities =
-      static_cast<TaskPriorityType>(TaskPriority::HIGHEST) + 1;
-  static constexpr uint8_t kNumBlockingModes = 2;
-  HistogramBase* const task_latency_histograms_[kNumTaskPriorities]
-                                               [kNumBlockingModes];
-  HistogramBase* const heartbeat_latency_histograms_[kNumTaskPriorities]
-                                                    [kNumBlockingModes];
-  HistogramBase* const
-      num_tasks_run_while_queuing_histograms_[kNumTaskPriorities]
-                                             [kNumBlockingModes];
-
   // Ensures all state (e.g. dangling cleaned up workers) is coalesced before
   // destroying the TaskTracker (e.g. in test environments).
   // Ref. https://crbug.com/827615.