cc: Keep track of busy resources in ResourcePool

cc/resources/resource_pool.cc

Index: cc/resources/resource_pool.cc
diff --git a/cc/resources/resource_pool.cc b/cc/resources/resource_pool.cc
index cef86ded1788d770100d996a1b2d2afc3de42718..2eacf248bee8e14fe552f0d8f1a3a756a578f722 100644
--- a/cc/resources/resource_pool.cc
+++ b/cc/resources/resource_pool.cc
@@ -82,7 +82,11 @@ void ResourcePool::ReleaseResource(
   }
 
   unused_memory_usage_bytes_ += resource->bytes();

[reveman, 2013/10/31 19:41:49]

This needs to be moved to CheckConsumedResources() instead.

-  unused_resources_.push_back(resource.release());
+
+  if (resource_provider_->InUseByConsumer(resource->id()))

[reveman, 2013/10/30 14:56:02]

Can we remove this check and always add released resources to
|consumed_resources_|? I'd prefer to only check InUseByConsumer in one place.

[danakj, 2013/10/30 15:12:40]

Yes you can RP holds onto it until it comes back from the parent before really
deleting it. 

[reveman, 2013/10/30 18:50:47]

I assume this is a reply to the above comment about destroying resources
currently in use by consumer. I'm not sure it's a good idea to allow these
resources to be removed from the pool if destruction is delayed as it would
cause the memory usage accounting here to be off.

[jadahl, 2013/10/31 08:38:42]

As far as I can see, this should be fine, as we always rebuild the list before
starting to schedule new tasks.

[reveman, 2013/10/31 19:41:49]

Yes, let's remove the ResourceUsageTooHigh() code above and always add the
resource to consumed_resources_ here.

+    consumed_resources_.push_back(resource.release());
+  else
+    unused_resources_.push_back(resource.release());
 }
 
 void ResourcePool::SetResourceUsageLimits(
@@ -127,4 +131,16 @@ bool ResourcePool::ResourceUsageTooHigh() {
   return false;
 }
 
+void ResourcePool::CheckConsumedResources() {
+  ResourceList::iterator it = consumed_resources_.begin();
+  while (it != consumed_resources_.end()) {

[reveman, 2013/10/30 14:56:02]

nit: consider using a temporary "Resource* resource = *it;" here. that's more
consistent with other loops in this file. 

+    if (!resource_provider_->InUseByConsumer((*it)->id())) {
+      unused_resources_.push_back(*it);
+      it = consumed_resources_.erase(it);
+    } else {
+      ++it;
+    }
+  }
+}
+
 }  // namespace cc