Reland - Refactor signaling in RWP

cc/raster/task_graph_work_queue.cc

 // 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 "cc/raster/task_graph_work_queue.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 177 matching lines @@
   // taking top priority task.
   if (!ready_to_run_tasks.empty()) {
     ready_to_run_namespaces.push_back(task_namespace);
     std::push_heap(ready_to_run_namespaces.begin(),
                    ready_to_run_namespaces.end(),
                    CompareTaskNamespacePriority(category));
   }
 
   // Add task to |running_tasks|.
   task_namespace->running_tasks.push_back(task.task);
+  running_task_count_[category]++;
 
   return task;
 }
 
 void TaskGraphWorkQueue::CompleteTask(const PrioritizedTask& completed_task) {
   TaskNamespace* task_namespace = completed_task.task_namespace;
   scoped_refptr<Task> task(completed_task.task);
 
   // Remove task from |running_tasks|.
   auto it = std::find(task_namespace->running_tasks.begin(),
                       task_namespace->running_tasks.end(), task);
   DCHECK(it != task_namespace->running_tasks.end());
   std::swap(*it, task_namespace->running_tasks.back());
   task_namespace->running_tasks.pop_back();
+  running_task_count_[completed_task.category]--;
 
   // Now iterate over all dependents to decrement dependencies and check if they
   // are ready to run.
   bool ready_to_run_namespaces_has_heap_properties = true;
   for (DependentIterator it(&task_namespace->graph, task.get()); it; ++it) {
     TaskGraph::Node& dependent_node = *it;
 
     DCHECK_LT(0u, dependent_node.dependencies);
     dependent_node.dependencies--;
     // Task is ready if it has no dependencies. Add it to |ready_to_run_tasks_|.
@@ skipping 67 matching lines @@
 
   for (const TaskGraph::Node& node : graph->nodes) {
     if (dependents[node.task] != node.dependencies)
       return true;
   }
 
   return false;
 }
 
 }  // namespace cc