aw: Track UI request GL separately from other threads

android_webview/browser/deferred_gpu_command_service.cc

 // Copyright 2014 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.
 
 #include "android_webview/browser/deferred_gpu_command_service.h"
 
 #include "android_webview/browser/gl_view_renderer_manager.h"
 #include "android_webview/browser/shared_renderer_state.h"
+#include "base/debug/trace_event.h"
 #include "base/synchronization/lock.h"
 #include "content/public/browser/android/synchronous_compositor.h"
 #include "gpu/command_buffer/service/shader_translator_cache.h"
 
 namespace android_webview {
 
 namespace {
 
 // TODO(boliu): Consider using base/atomicops.h.
 class ThreadSafeBool {
  public:
   ThreadSafeBool();
   void Set(bool boolean);
   bool Get();
+  bool GetAndSet();
 
  private:
   base::Lock lock_;
   bool boolean_;
   DISALLOW_COPY_AND_ASSIGN(ThreadSafeBool);
 };
 
 ThreadSafeBool::ThreadSafeBool() : boolean_(false) {
 }
 
 void ThreadSafeBool::Set(bool boolean) {
   base::AutoLock lock(lock_);
   boolean_ = boolean;
 }
 
+bool ThreadSafeBool::GetAndSet() {
+  base::AutoLock lock(lock_);
+  bool rv = boolean_;
+  boolean_ = true;
+  return rv;
+}
+
 bool ThreadSafeBool::Get() {
   base::AutoLock lock(lock_);
   return boolean_;
 }
 
 base::LazyInstance<ThreadSafeBool> g_request_pending =
     LAZY_INSTANCE_INITIALIZER;
 
+// Because request is posted to UI thread, have to treat requests on UI thread
+// specifically because UI can immediately block waiting for the request.
+base::LazyInstance<ThreadSafeBool> g_request_pending_on_ui =
+    LAZY_INSTANCE_INITIALIZER;
+
 base::LazyInstance<scoped_refptr<DeferredGpuCommandService> >
     g_service = LAZY_INSTANCE_INITIALIZER;
 }  // namespace
 
 base::LazyInstance<base::ThreadLocalBoolean> ScopedAllowGL::allow_gl;
 
 // static
 bool ScopedAllowGL::IsAllowed() {
   return allow_gl.Get().Get();
 }
 
 ScopedAllowGL::ScopedAllowGL() {
   DCHECK(!allow_gl.Get().Get());
   allow_gl.Get().Set(true);
 
   if (g_service.Get())
     g_service.Get()->RunTasks();
 }
 
 ScopedAllowGL::~ScopedAllowGL() {
   allow_gl.Get().Set(false);
   g_request_pending.Get().Set(false);
+  g_request_pending_on_ui.Get().Set(false);
 
   DeferredGpuCommandService* service = g_service.Get();
   if (service) {
     service->RunTasks();
     if (service->HasIdleWork()) {
       service->RequestProcessGL();
     }
   }
 }
 
 // static
 void DeferredGpuCommandService::SetInstance() {
   if (!g_service.Get()) {
     g_service.Get() = new DeferredGpuCommandService;
     content::SynchronousCompositor::SetGpuService(g_service.Get());
 
     // Initialize global booleans.
     g_request_pending.Get().Set(false);
+    g_request_pending_on_ui.Get().Set(false);
   }
 }
 
 // static
 DeferredGpuCommandService* DeferredGpuCommandService::GetInstance() {
   DCHECK(g_service.Get().get());
   return g_service.Get().get();
 }
 
 DeferredGpuCommandService::DeferredGpuCommandService() {}
 
 DeferredGpuCommandService::~DeferredGpuCommandService() {
   base::AutoLock lock(tasks_lock_);
   DCHECK(tasks_.empty());
 }
 
 // This method can be called on any thread.
 // static
 void DeferredGpuCommandService::RequestProcessGL() {
   SharedRendererState* renderer_state =
       GLViewRendererManager::GetInstance()->GetMostRecentlyDrawn();
   if (!renderer_state) {
     LOG(ERROR) << "No hardware renderer. Deadlock likely";
     return;
   }
 
-  if (!g_request_pending.Get().Get()) {
+  bool on_ui_thread = renderer_state->CurrentlyOnUIThread();
+  bool need_request = on_ui_thread ? !g_request_pending_on_ui.Get().GetAndSet()
+                                   : !g_request_pending.Get().GetAndSet();
+  if (need_request) {
     g_request_pending.Get().Set(true);
     renderer_state->ClientRequestDrawGL();
   }
 }
 
 // Called from different threads!
 void DeferredGpuCommandService::ScheduleTask(const base::Closure& task) {
   {
     base::AutoLock lock(tasks_lock_);
     tasks_.push(task);
@@ skipping 13 matching lines @@
 void DeferredGpuCommandService::ScheduleIdleWork(
     const base::Closure& callback) {
   {
     base::AutoLock lock(tasks_lock_);
     idle_tasks_.push(std::make_pair(base::Time::Now(), callback));
   }
   RequestProcessGL();
 }
 
 void DeferredGpuCommandService::PerformIdleWork(bool is_idle) {
+  TRACE_EVENT1("android_webview",
+               "DeferredGpuCommandService::PerformIdleWork",
+               "is_idle",
+               is_idle);
   DCHECK(ScopedAllowGL::IsAllowed());
   static const base::TimeDelta kMaxIdleAge =
       base::TimeDelta::FromMilliseconds(16);
 
   const base::Time now = base::Time::Now();
   while (HasIdleWork()) {
     base::Closure task;
     {
       base::AutoLock lock(tasks_lock_);
       if (!is_idle) {
@@ skipping 42 matching lines @@
 
 void DeferredGpuCommandService::AddRef() const {
   base::RefCountedThreadSafe<DeferredGpuCommandService>::AddRef();
 }
 
 void DeferredGpuCommandService::Release() const {
   base::RefCountedThreadSafe<DeferredGpuCommandService>::Release();
 }
 
 }  // namespace android_webview