Bug 1880503 - Handle sync IPC timeout in UiCompositorControllerChild. r=aosmond

Extend the sync IPC timeout mechanism in CompositorManagerChild to
additionally cover UiCompositorControllerChild. As
UiCompositorControllerChild runs on the Android UI thread, we ensure
GPUProcessManager::KillProcess dispatches to the gecko main thread.

Along with the previous patch in this series this should provide us
with crash reports when the Android UI thread is hung waiting for the
GPU process to reply.

Differential Revision: https://phabricator.services.mozilla.com/D202167

gfx/ipc/GPUProcessHost.cpp

@@ -212,6 +212,8 @@ void GPUProcessHost::OnChannelClosed() {
 }
 
 void GPUProcessHost::KillHard(bool aGenerateMinidump) {
+  MOZ_ASSERT(NS_IsMainThread());
+
   if (mGPUChild && aGenerateMinidump) {
     mGPUChild->GeneratePairedMinidump();
   }

gfx/ipc/GPUProcessManager.cpp

@@ -1122,6 +1122,13 @@ void GPUProcessManager::CleanShutdown() {
 }
 
 void GPUProcessManager::KillProcess(bool aGenerateMinidump) {
+  if (!NS_IsMainThread()) {
+    RefPtr<Runnable> task = mTaskFactory.NewRunnableMethod(
+        &GPUProcessManager::KillProcess, aGenerateMinidump);
+    NS_DispatchToMainThread(task.forget());
+    return;
+  }
+
   if (!mProcess) {
     return;
   }

gfx/layers/ipc/UiCompositorControllerChild.cpp

@@ -13,6 +13,7 @@
 #include "mozilla/layers/UiCompositorControllerParent.h"
 #include "mozilla/gfx/GPUProcessManager.h"
 #include "mozilla/ipc/Endpoint.h"
+#include "mozilla/StaticPrefs_layers.h"
 #include "mozilla/StaticPtr.h"
 #include "nsBaseWidget.h"
 #include "nsProxyRelease.h"
@@ -287,6 +288,8 @@ void UiCompositorControllerChild::OpenForGPUProcess(
     return;
   }
 
+  SetReplyTimeout();
+
   SendCachedValues();
   // Let Ui thread know the connection is open;
   RecvToolbarAnimatorMessageFromCompositor(COMPOSITOR_CONTROLLER_OPEN);
@@ -346,5 +349,20 @@ void UiCompositorControllerChild::OnCompositorSurfaceChanged(
 }
 #endif
 
+void UiCompositorControllerChild::SetReplyTimeout() {
+#ifndef DEBUG
+  // Add a timeout for release builds to kill GPU process when it hangs.
+  const int32_t timeout =
+      StaticPrefs::layers_gpu_process_ipc_reply_timeout_ms_AtStartup();
+  SetReplyTimeoutMs(timeout);
+#endif
+}
+
+bool UiCompositorControllerChild::ShouldContinueFromReplyTimeout() {
+  gfxCriticalNote << "Killing GPU process due to IPC reply timeout";
+  gfx::GPUProcessManager::Get()->KillProcess(/* aGenerateMinidump */ true);
+  return false;
+}
+
 }  // namespace layers
 }  // namespace mozilla

gfx/layers/ipc/UiCompositorControllerChild.h

@@ -94,6 +94,9 @@ class UiCompositorControllerChild final
   void OpenForGPUProcess(Endpoint<PUiCompositorControllerChild>&& aEndpoint);
   void SendCachedValues();
 
+  void SetReplyTimeout();
+  bool ShouldContinueFromReplyTimeout() override;
+
   bool mIsOpen;
   uint64_t mProcessToken;
   Maybe<gfx::IntRect> mResize;