Reland 179911 and 179910

gpu/command_buffer/service/gpu_scheduler.cc

 // Copyright (c) 2012 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 "gpu/command_buffer/service/gpu_scheduler.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/debug/trace_event.h"
@@ skipping 47 matching lines @@
   if (!PollUnscheduleFences())
     return;
 
   // One of the unschedule fence tasks might have unscheduled us.
   if (!IsScheduled())
     return;
 
   base::TimeTicks begin_time(base::TimeTicks::HighResNow());
   error::Error error = error::kNoError;
   while (!parser_->IsEmpty()) {
-    if (preempt_by_counter_.get() &&
-        !was_preempted_ &&
-        !preempt_by_counter_->IsZero()) {
-      TRACE_COUNTER_ID1("gpu","GpuScheduler::Preempted", this, 1);
-      was_preempted_ = true;
+    if (IsPreempted())
       break;
-    } else if (was_preempted_) {
-      TRACE_COUNTER_ID1("gpu","GpuScheduler::Preempted", this, 0);
-      was_preempted_ = false;
-    }
 
     DCHECK(IsScheduled());
     DCHECK(unschedule_fences_.empty());
 
     error = parser_->ProcessCommand();
 
     if (error == error::kDeferCommandUntilLater) {
       DCHECK(unscheduled_count_ > 0);
       break;
     }
@@ skipping 160 matching lines @@
     while (!unschedule_fences_.empty()) {
       unschedule_fences_.front()->task.Run();
       unschedule_fences_.pop();
       SetScheduled(true);
     }
   }
 
   return true;
 }
 
+bool GpuScheduler::IsPreempted() {
+  if (!preemption_flag_.get())
+    return false;
+
+  if (!was_preempted_ && !preemption_flag_->IsSet()) {
+    TRACE_COUNTER_ID1("gpu", "GpuScheduler::Preempted", this, 1);
+    was_preempted_ = true;
+  } else if (was_preempted_) {
+    TRACE_COUNTER_ID1("gpu", "GpuScheduler::Preempted", this, 0);
+    was_preempted_ = false;
+  }
+
+  return !preemption_flag_->IsSet();
+}
+
 void GpuScheduler::RescheduleTimeOut() {
   int new_count = unscheduled_count_ + rescheduled_count_;
 
   rescheduled_count_ = 0;
 
   while (unscheduled_count_)
     SetScheduled(true);
 
   rescheduled_count_ = new_count;
 }
 
 GpuScheduler::UnscheduleFence::UnscheduleFence(
     gfx::GLFence* fence_, base::Closure task_): fence(fence_), task(task_) {
 }
 
 GpuScheduler::UnscheduleFence::~UnscheduleFence() {
 }
 
 }  // namespace gpu