1 // Copyright 2013 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 #include "content/renderer/render_process_visibility_manager.h" 6 7 #include "base/logging.h" 8 #include "base/memory/memory_pressure_listener.h" 9 10 namespace content { 11 12 RenderProcessVisibilityManager::RenderProcessVisibilityManager() 13 : num_visible_render_widgets_(0) { 14 } 15 16 RenderProcessVisibilityManager::~RenderProcessVisibilityManager() { 17 } 18 19 // static 20 RenderProcessVisibilityManager* RenderProcessVisibilityManager::GetInstance() { 21 return Singleton<RenderProcessVisibilityManager>::get(); 22 } 23 24 void RenderProcessVisibilityManager::WidgetVisibilityChanged(bool visible) { 25 #if !defined(SYSTEM_NATIVELY_SIGNALS_MEMORY_PRESSURE) 26 num_visible_render_widgets_ += visible ? 1 : -1; 27 DCHECK_LE(0, num_visible_render_widgets_); 28 if (num_visible_render_widgets_ == 0) { 29 // TODO(vollick): Remove this this heavy-handed approach once we're polling 30 // the real system memory pressure. 31 base::MemoryPressureListener::NotifyMemoryPressure( 32 base::MemoryPressureListener::MEMORY_PRESSURE_MODERATE); 33 } 34 #endif 35 } 36 37 } // namespace content 38