gpu: Thread-safe command buffer state lookup.

gpu/command_buffer/client/cmd_buffer_helper_test.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.
 
 // Tests for the Command Buffer Helper.
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
@@ skipping 50 matching lines @@
       last_flush_ = put_offset;
     }
   }
 
   void LockFlush() { flush_locked_ = true; }
 
   void UnlockFlush() { flush_locked_ = false; }
 
   int FlushCount() { return flush_count_; }
 
-  void WaitForGetOffsetInRange(int32_t start, int32_t end) override {
+  State WaitForGetOffsetInRange(int32_t start, int32_t end) override {
     // Flush only if it's required to unblock this Wait.
     if (last_flush_ != -1 &&
         !CommandBuffer::InRange(start, end, previous_put_offset_)) {
       previous_put_offset_ = last_flush_;
       CommandBufferService::Flush(last_flush_);
       last_flush_ = -1;
     }
-    CommandBufferService::WaitForGetOffsetInRange(start, end);
+    return CommandBufferService::WaitForGetOffsetInRange(start, end);
   }
 
  private:
   bool flush_locked_;
   int last_flush_;
   int previous_put_offset_;
   int flush_count_;
   DISALLOW_COPY_AND_ASSIGN(CommandBufferServiceLocked);
 };
 
@@ skipping 150 matching lines @@
         // we're on the bottom side, check we are below get.
         EXPECT_GT(parser_get, limit);
       }
     }
   }
 
   int32_t GetGetOffset() { return command_buffer_->GetLastState().get_offset; }
 
   int32_t GetPutOffset() { return command_buffer_->GetPutOffset(); }
 
-  int32_t GetHelperGetOffset() { return helper_->get_offset(); }
+  int32_t GetHelperGetOffset() { return helper_->cached_get_offset_; }
 
   int32_t GetHelperPutOffset() { return helper_->put_; }
 
   uint32_t GetHelperFlushGeneration() { return helper_->flush_generation(); }
 
   error::Error GetError() {
     return command_buffer_->GetLastState().error;
   }
 
   CommandBufferOffset get_helper_put() { return helper_->put_; }
@@ skipping 502 matching lines @@
   helper_->OrderingBarrier();
   flush_count2 = command_buffer_->FlushCount();
   helper_->OrderingBarrier();
   flush_count3 = command_buffer_->FlushCount();
 
   EXPECT_EQ(flush_count2, flush_count1 + 1);
   EXPECT_EQ(flush_count3, flush_count2 + 1);
 }
 
 }  // namespace gpu