cc: Add tracing for unused memory in resource pool.

This includes the amount of unused memory in the resource pool
in "DidManage" traces and adds a trace counter that is updated
each time ManageTiles is called.

BUG=272453

Review URL: https://chromiumcodereview.appspot.com/23208002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@217686 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 15 insertions, 2 deletions

diff --git a/cc/resources/resource_pool.h b/cc/resources/resource_pool.h
index 2304a50..309bf33 100644
--- a/cc/resources/resource_pool.h
+++ b/cc/resources/resource_pool.h
@@ -44,6 +44,9 @@ class CC_EXPORT ResourcePool {
                             size_t max_unused_memory_usage_bytes,
                             size_t num_resources_limit);
 
+  size_t total_memory_usage_bytes() const {
+    return memory_usage_bytes_;
+  }
   size_t acquired_memory_usage_bytes() const {
     return memory_usage_bytes_ - unused_memory_usage_bytes_;
   }
diff --git a/cc/resources/tile_manager.cc b/cc/resources/tile_manager.cc
index 9968195..7cf5096 100644
--- a/cc/resources/tile_manager.cc
+++ b/cc/resources/tile_manager.cc
@@ -362,12 +362,16 @@ void TileManager::ManageTiles() {
                          &tiles_that_need_to_be_rasterized);
   CleanUpUnusedImageDecodeTasks();
 
+  // Finally, schedule rasterizer tasks.
+  ScheduleTasks(tiles_that_need_to_be_rasterized);
+
   TRACE_EVENT_INSTANT1(
       "cc", "DidManage", TRACE_EVENT_SCOPE_THREAD,
       "state", TracedValue::FromValue(BasicStateAsValue().release()));
 
-  // Finally, schedule rasterizer tasks.
-  ScheduleTasks(tiles_that_need_to_be_rasterized);
+  TRACE_COUNTER_ID1("cc", "unused_memory_bytes", this,
+                    resource_pool_->total_memory_usage_bytes() -
+                    resource_pool_->acquired_memory_usage_bytes());
 }
 
 bool TileManager::UpdateVisibleTiles() {
@@ -390,9 +394,11 @@ bool TileManager::UpdateVisibleTiles() {
 void TileManager::GetMemoryStats(
     size_t* memory_required_bytes,
     size_t* memory_nice_to_have_bytes,
+    size_t* memory_allocated_bytes,
     size_t* memory_used_bytes) const {
   *memory_required_bytes = 0;
   *memory_nice_to_have_bytes = 0;
+  *memory_allocated_bytes = resource_pool_->total_memory_usage_bytes();
   *memory_used_bytes = resource_pool_->acquired_memory_usage_bytes();
   for (TileMap::const_iterator it = tiles_.begin();
        it != tiles_.end();
@@ -439,13 +445,16 @@ scoped_ptr<base::Value> TileManager::GetMemoryRequirementsAsValue() const {
 
   size_t memory_required_bytes;
   size_t memory_nice_to_have_bytes;
+  size_t memory_allocated_bytes;
   size_t memory_used_bytes;
   GetMemoryStats(&memory_required_bytes,
                  &memory_nice_to_have_bytes,
+                 &memory_allocated_bytes,
                  &memory_used_bytes);
   requirements->SetInteger("memory_required_bytes", memory_required_bytes);
   requirements->SetInteger("memory_nice_to_have_bytes",
                            memory_nice_to_have_bytes);
+  requirements->SetInteger("memory_allocated_bytes", memory_allocated_bytes);
   requirements->SetInteger("memory_used_bytes", memory_used_bytes);
   return requirements.PassAs<base::Value>();
 }
diff --git a/cc/resources/tile_manager.h b/cc/resources/tile_manager.h
index 2e226c9..7957fc8 100644
--- a/cc/resources/tile_manager.h
+++ b/cc/resources/tile_manager.h
@@ -69,6 +69,7 @@ class CC_EXPORT TileManager : public RasterWorkerPoolClient {
   scoped_ptr<base::Value> AllTilesAsValue() const;
   void GetMemoryStats(size_t* memory_required_bytes,
                       size_t* memory_nice_to_have_bytes,
+                      size_t* memory_allocated_bytes,
                       size_t* memory_used_bytes) const;
 
   const MemoryHistory::Entry& memory_stats_from_last_assign() const {