Add a testing pref to let the GPU process restart multiple times. (bug 1305941, r=mattwoodrow)

gfx/ipc/GPUProcessManager.cpp

@@ -59,6 +59,7 @@ GPUProcessManager::Shutdown()
 GPUProcessManager::GPUProcessManager()
  : mTaskFactory(this),
    mNextLayerTreeId(0),
+   mNumProcessAttempts(0),
    mProcess(nullptr),
    mGPUChild(nullptr)
 {
@@ -107,7 +108,7 @@ GPUProcessManager::OnXPCOMShutdown()
 }
 
 void
-GPUProcessManager::EnableGPUProcess()
+GPUProcessManager::LaunchGPUProcess()
 {
   if (mProcess) {
     return;
@@ -116,6 +117,8 @@ GPUProcessManager::EnableGPUProcess()
   // Start the Vsync I/O thread so can use it as soon as the process launches.
   EnsureVsyncIOThread();
 
+  mNumProcessAttempts++;
+
   // The subprocess is launched asynchronously, so we wait for a callback to
   // acquire the IPDL actor.
   mProcess = new GPUProcessHost(this);
@@ -127,6 +130,10 @@ GPUProcessManager::EnableGPUProcess()
 void
 GPUProcessManager::DisableGPUProcess(const char* aMessage)
 {
+  if (!gfxConfig::IsEnabled(Feature::GPU_PROCESS)) {
+    return;
+  }
+
   gfxConfig::SetFailed(Feature::GPU_PROCESS, FeatureStatus::Failed, aMessage);
   gfxCriticalNote << aMessage;
 
@@ -247,6 +254,13 @@ GPUProcessManager::OnProcessUnexpectedShutdown(GPUProcessHost* aHost)
 
   DestroyProcess();
 
+  if (mNumProcessAttempts > uint32_t(gfxPrefs::GPUProcessDevMaxRestarts())) {
+    DisableGPUProcess("GPU processed crashed too many times");
+  }
+  if (gfxConfig::IsEnabled(Feature::GPU_PROCESS)) {
+    LaunchGPUProcess();
+  }
+
   // The shutdown and restart sequence for the GPU process is as follows:
   //
   //  (1) The GPU process dies. IPDL will enqueue an ActorDestroy message on

gfx/ipc/GPUProcessManager.h

@@ -73,7 +73,7 @@ public:
   ~GPUProcessManager();
 
   // If not using a GPU process, launch a new GPU process asynchronously.
-  void EnableGPUProcess();
+  void LaunchGPUProcess();
 
   // Ensure that GPU-bound methods can be used. If no GPU process is being
   // used, or one is launched and ready, this function returns immediately.
@@ -194,6 +194,7 @@ private:
   ipc::TaskFactory<GPUProcessManager> mTaskFactory;
   RefPtr<VsyncIOThreadHolder> mVsyncIOThread;
   uint64_t mNextLayerTreeId;
+  uint32_t mNumProcessAttempts;
 
   nsTArray<RefPtr<RemoteCompositorSession>> mRemoteSessions;
   nsTArray<GPUProcessListener*> mListeners;

gfx/thebes/gfxPlatform.cpp

@@ -2178,7 +2178,7 @@ gfxPlatform::InitAcceleration()
 
     if (gpuProc.IsEnabled()) {
       GPUProcessManager* gpu = GPUProcessManager::Get();
-      gpu->EnableGPUProcess();
+      gpu->LaunchGPUProcess();
     }
   }
 }

gfx/thebes/gfxPrefs.h

@@ -479,6 +479,7 @@ private:
   DECL_GFX_PREF(Live, "layers.frame-counter",                  DrawFrameCounter, bool, false);
   DECL_GFX_PREF(Once, "layers.gpu-process.dev.enabled",        GPUProcessDevEnabled, bool, false);
   DECL_GFX_PREF(Once, "layers.gpu-process.dev.timeout_ms",     GPUProcessDevTimeoutMs, int32_t, 5000);
+  DECL_GFX_PREF(Live, "layers.gpu-process.dev.max_restarts",   GPUProcessDevMaxRestarts, int32_t, 0);
   DECL_GFX_PREF(Once, "layers.gralloc.disable",                DisableGralloc, bool, false);
   DECL_GFX_PREF(Live, "layers.low-precision-buffer",           UseLowPrecisionBuffer, bool, false);
   DECL_GFX_PREF(Live, "layers.low-precision-opacity",          LowPrecisionOpacity, float, 1.0f);