1 // Copyright 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef CC_SCHEDULER_RATE_LIMITER_H_ 6 #define CC_SCHEDULER_RATE_LIMITER_H_ 7 8 #include "base/memory/ref_counted.h" 9 10 namespace base { class SingleThreadTaskRunner; } 11 12 namespace WebKit { class WebGraphicsContext3D; } 13 14 namespace cc { 15 16 class RateLimiterClient { 17 public: 18 virtual void RateLimit() = 0; 19 20 protected: 21 virtual ~RateLimiterClient() {} 22 }; 23 24 // A RateLimiter can be used to make sure that a single context does not 25 // dominate all execution time. To use, construct a RateLimiter class around 26 // the context and call Start() whenever calls are made on the context outside 27 // of normal flow control. RateLimiter will block if the context is too far 28 // ahead of the compositor. 29 class RateLimiter : public base::RefCounted<RateLimiter> { 30 public: 31 static scoped_refptr<RateLimiter> Create( 32 WebKit::WebGraphicsContext3D* context, 33 RateLimiterClient* client, 34 base::SingleThreadTaskRunner* task_runner); 35 36 void Start(); 37 38 // Context and client will not be accessed after Stop(). 39 void Stop(); 40 41 private: 42 friend class base::RefCounted<RateLimiter>; 43 44 RateLimiter(WebKit::WebGraphicsContext3D* context, 45 RateLimiterClient* client, 46 base::SingleThreadTaskRunner* task_runner); 47 ~RateLimiter(); 48 49 void RateLimitContext(); 50 51 WebKit::WebGraphicsContext3D* context_; 52 bool active_; 53 RateLimiterClient* client_; 54 base::SingleThreadTaskRunner* task_runner_; 55 56 DISALLOW_COPY_AND_ASSIGN(RateLimiter); 57 }; 58 59 } // namespace cc 60 61 #endif // CC_SCHEDULER_RATE_LIMITER_H_ 62
