gpu: Thread-safe command buffer state lookup.

gpu/ipc/in_process_command_buffer.cc

Index: gpu/ipc/in_process_command_buffer.cc
diff --git a/gpu/ipc/in_process_command_buffer.cc b/gpu/ipc/in_process_command_buffer.cc
index a30b1e17e7ba1a1a4d304a13f5f999ea5b8ebefd..437cdc7dae86a3811ae0b1be61d7e457aac44ff7 100644
--- a/gpu/ipc/in_process_command_buffer.cc
+++ b/gpu/ipc/in_process_command_buffer.cc
@@ -617,16 +617,19 @@ void InProcessCommandBuffer::OrderingBarrier(int32_t put_offset) {
   Flush(put_offset);
 }
 
-void InProcessCommandBuffer::WaitForTokenInRange(int32_t start, int32_t end) {
+CommandBuffer::State InProcessCommandBuffer::WaitForTokenInRange(int32_t start,
+                                                                 int32_t end) {
   CheckSequencedThread();
   while (!InRange(start, end, GetLastToken()) &&
          last_state_.error == gpu::error::kNoError) {
     flush_event_.Wait();
   }
+  return last_state_;
 }
 
-void InProcessCommandBuffer::WaitForGetOffsetInRange(int32_t start,
-                                                     int32_t end) {
+CommandBuffer::State InProcessCommandBuffer::WaitForGetOffsetInRange(
+    int32_t start,
+    int32_t end) {
   CheckSequencedThread();
 
   GetStateFast();
@@ -635,6 +638,7 @@ void InProcessCommandBuffer::WaitForGetOffsetInRange(int32_t start,
     flush_event_.Wait();
     GetStateFast();
   }
+  return last_state_;
 }
 
 void InProcessCommandBuffer::SetGetBuffer(int32_t shm_id) {
@@ -1030,6 +1034,11 @@ bool InProcessCommandBuffer::IsFenceSyncFlushReceived(uint64_t release) {
   return IsFenceSyncFlushed(release);
 }
 
+bool InProcessCommandBuffer::IsFenceSyncReleased(uint64_t release) {
+  State state = GetStateFast();
+  return release <= state.release_count;
+}
+
 void InProcessCommandBuffer::SignalSyncToken(const SyncToken& sync_token,
                                              const base::Closure& callback) {
   CheckSequencedThread();