1 /* 2 * Copyright (C) 2014 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_HEAP_IMPL_GC_TASK_RUNNER_H_ 32 #define THIRD_PARTY_BLINK_RENDERER_PLATFORM_HEAP_IMPL_GC_TASK_RUNNER_H_ 33 34 #include <memory> 35 #include "base/location.h" 36 #include "third_party/blink/renderer/platform/heap/thread_state.h" 37 #include "third_party/blink/renderer/platform/scheduler/public/thread.h" 38 #include "third_party/blink/renderer/platform/wtf/cross_thread_functional.h" 39 40 namespace blink { 41 42 class GCTaskObserver final : public Thread::TaskObserver { 43 USING_FAST_MALLOC(GCTaskObserver); 44 45 public: GCTaskObserver()46 GCTaskObserver() : nesting_(0) {} 47 ~GCTaskObserver()48 ~GCTaskObserver() override { 49 // m_nesting can be 1 if this was unregistered in a task and 50 // didProcessTask was not called. 51 DCHECK(!nesting_ || nesting_ == 1); 52 } 53 WillProcessTask(const base::PendingTask &,bool)54 void WillProcessTask(const base::PendingTask&, bool) override { nesting_++; } 55 DidProcessTask(const base::PendingTask &)56 void DidProcessTask(const base::PendingTask&) override { 57 // In the production code WebKit::initialize is called from inside the 58 // message loop so we can get didProcessTask() without corresponding 59 // willProcessTask once. This is benign. 60 if (nesting_) 61 nesting_--; 62 63 ThreadState::Current()->SafePoint(nesting_ 64 ? BlinkGC::kHeapPointersOnStack 65 : BlinkGC::kNoHeapPointersOnStack); 66 } 67 68 private: 69 int nesting_; 70 }; 71 72 class GCTaskRunner final { 73 USING_FAST_MALLOC(GCTaskRunner); 74 75 public: GCTaskRunner(Thread * thread)76 explicit GCTaskRunner(Thread* thread) 77 : gc_task_observer_(std::make_unique<GCTaskObserver>()), thread_(thread) { 78 thread_->AddTaskObserver(gc_task_observer_.get()); 79 } 80 ~GCTaskRunner()81 ~GCTaskRunner() { thread_->RemoveTaskObserver(gc_task_observer_.get()); } 82 83 private: 84 std::unique_ptr<GCTaskObserver> gc_task_observer_; 85 Thread* thread_; 86 }; 87 88 } // namespace blink 89 90 #endif // THIRD_PARTY_BLINK_RENDERER_PLATFORM_HEAP_IMPL_GC_TASK_RUNNER_H_ 91