Adding flow traces for blink scheduler events

Source/platform/scheduler/Scheduler.cpp

 // Copyright 2014 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 "config.h"
 #include "platform/scheduler/Scheduler.h"
 
 #include "platform/PlatformThreadData.h"
 #include "platform/Task.h"
 #include "platform/ThreadTimers.h"
 #include "platform/TraceEvent.h"
 #include "public/platform/Platform.h"
 #include "wtf/MainThread.h"
-#include "wtf/ThreadingPrimitives.h"
-
 
 namespace blink {
 
 namespace {
 
 // The time we should stay in CompositorPriority mode for, after a touch event.
 double kLowSchedulerPolicyAfterTouchTimeSeconds = 0.1;
 
 // Can be created from any thread.
 // Note if the scheduler gets shutdown, this may be run after.
@@ skipping 45 matching lines @@
         scheduler->swapQueuesRunPendingTasksAndAllowHighPriorityTaskRunnerPosting();
     }
 };
 
 
 // Can be created from any thread.
 // Note if the scheduler gets shutdown, this may be run after.
 class Scheduler::MainThreadPendingTaskRunner : public WebThread::Task {
 public:
     MainThreadPendingTaskRunner(
-        const Scheduler::Task& task, const TraceLocation& location)
-        : m_task(task, location)
+        const Scheduler::Task& task, const TraceLocation& location, const char* traceName)
+        : m_task(task, location, traceName)
     {
         ASSERT(Scheduler::shared());
     }
 
     // WebThread::Task implementation.
     virtual void run() OVERRIDE
     {
         Scheduler* scheduler = Scheduler::shared();
         // FIXME: This check should't be necessary, tasks should not outlive blink.
         ASSERT(scheduler);
         if (scheduler)
             Scheduler::shared()->runPendingHighPriorityTasksIfInCompositorPriority();
         m_task.run();
     }
 
-    Scheduler::TracedTask m_task;
+    TracedTask m_task;
 };
 
 Scheduler* Scheduler::s_sharedScheduler = nullptr;
 
 void Scheduler::initializeOnMainThread()
 {
     s_sharedScheduler = new Scheduler();
 }
 
 void Scheduler::shutdown()
@@ skipping 33 matching lines @@
 {
     // TODO: Trigger the frame deadline immediately.
 }
 
 void Scheduler::scheduleIdleTask(const TraceLocation& location, const IdleTask& idleTask)
 {
     // TODO: send a real allottedTime here.
     m_mainThread->postTask(new MainThreadIdleTaskAdapter(idleTask, 0, location));
 }
 
-void Scheduler::postTask(const TraceLocation& location, const Task& task)
-{
-    m_mainThread->postTask(new MainThreadPendingTaskRunner(task, location));
-}
-
-void Scheduler::postInputTask(const TraceLocation& location, const Task& task)
+void Scheduler::postHighPriorityTaskInternal(const TraceLocation& location, const Task& task, const char* traceName)
 {
     Locker<Mutex> lock(m_pendingTasksMutex);
-    m_pendingHighPriorityTasks.append(TracedTask(task, location));
+
+    m_pendingHighPriorityTasks.append(TracedTask(task, location, traceName));
     atomicIncrement(&m_highPriorityTaskCount);
     maybePostMainThreadPendingHighPriorityTaskRunner();
     TRACE_COUNTER1(TRACE_DISABLED_BY_DEFAULT("blink.scheduler"), "PendingHighPriorityTasks", m_highPriorityTaskCount);
 }
 
+void Scheduler::postTask(const TraceLocation& location, const Task& task)
+{
+    m_mainThread->postTask(new MainThreadPendingTaskRunner(task, location, "Scheduler::MainThreadTask"));
+}
+
+void Scheduler::postInputTask(const TraceLocation& location, const Task& task)
+{
+    postHighPriorityTaskInternal(location, task, "Scheduler::InputTask");
+}
+
 void Scheduler::didReceiveInputEvent()
 {
     enterSchedulerPolicy(CompositorPriority);
 }
 
 void Scheduler::postCompositorTask(const TraceLocation& location, const Task& task)
 {
-    Locker<Mutex> lock(m_pendingTasksMutex);
-    m_pendingHighPriorityTasks.append(TracedTask(task, location));
-    atomicIncrement(&m_highPriorityTaskCount);
-    maybePostMainThreadPendingHighPriorityTaskRunner();
-    TRACE_COUNTER1(TRACE_DISABLED_BY_DEFAULT("blink.scheduler"), "PendingHighPriorityTasks", m_highPriorityTaskCount);
+    postHighPriorityTaskInternal(location, task, "Scheduler::CompositorTask");
 }
 
 void Scheduler::maybePostMainThreadPendingHighPriorityTaskRunner()
 {
     ASSERT(m_pendingTasksMutex.locked());
     if (m_highPriorityTaskRunnerPosted)
         return;
     m_mainThread->postTask(new MainThreadPendingHighPriorityTaskRunner());
     m_highPriorityTaskRunnerPosted = true;
 }
@@ skipping 136 matching lines @@
 void Scheduler::enterSchedulerPolicyLocked(SchedulerPolicy schedulerPolicy)
 {
     ASSERT(m_pendingTasksMutex.locked());
     if (schedulerPolicy == CompositorPriority)
         m_compositorPriorityPolicyEndTimeSeconds = Platform::current()->monotonicallyIncreasingTime() + kLowSchedulerPolicyAfterTouchTimeSeconds;
 
     releaseStore(&m_schedulerPolicy, schedulerPolicy);
     TRACE_COUNTER1(TRACE_DISABLED_BY_DEFAULT("blink.scheduler"), "SchedulerPolicy", schedulerPolicy);
 }
 
-void Scheduler::TracedTask::run()
-{
-    TRACE_EVENT2("blink", "TracedTask::run",
-        "src_file", m_location.fileName(),
-        "src_func", m_location.functionName());
-    m_task();
-}
-
 } // namespace blink