Bug 1564127 - Check if GPU/VR process has connected with the parent process. r=kip

This issue happens when VR/GPU haven't connected with the parent process via IPC protocol, and we are trying to access its IPC Child when it is still null. It is possible to be happened when GPU/VR process is killed/shutdown, and we are trying to launch a new VR process. We need to check these status before completing our VR process's launch.

Differential Revision: https://phabricator.services.mozilla.com/D46540

--HG--
extra : moz-landing-system : lando

Author: daoshengmu

gfx/vr/ipc/VRProcessManager.cpp

@@ -154,6 +154,11 @@ bool VRProcessManager::CreateGPUBridges(
 bool VRProcessManager::CreateGPUVRManager(
     base::ProcessId aOtherProcess,
     mozilla::ipc::Endpoint<PVRGPUChild>* aOutEndpoint) {
+  if (mProcess && !mProcess->IsConnected()) {
+    NS_WARNING("VR process haven't connected with the parent process yet");
+    return false;
+  }
+
   base::ProcessId vrparentPid = mProcess
                                     ? mProcess->OtherPid()  // VR process id.
                                     : base::GetCurrentProcId();

gfx/vr/ipc/VRProcessParent.cpp

@@ -96,7 +96,7 @@ bool VRProcessParent::WaitForLaunch() {
   // immediately set up the IPDL actor and fire callbacks. The IO thread will
   // still dispatch a notification to the main thread - we'll just ignore it.
   bool result = GeckoChildProcessHost::WaitUntilConnected(timeoutMs);
-  InitAfterConnect(result);
+  result &= InitAfterConnect(result);
   return result;
 }
 
@@ -138,14 +138,22 @@ void VRProcessParent::DestroyProcess() {
   }
 }
 
-void VRProcessParent::InitAfterConnect(bool aSucceeded) {
+bool VRProcessParent::InitAfterConnect(bool aSucceeded) {
   MOZ_ASSERT(mLaunchPhase == LaunchPhase::Waiting);
   MOZ_ASSERT(!mVRChild);
 
   mLaunchPhase = LaunchPhase::Complete;
   mPrefSerializer = nullptr;
 
   if (aSucceeded) {
+    GPUChild* gpuChild = GPUProcessManager::Get()->GetGPUChild();
+    if (!gpuChild) {
+      NS_WARNING(
+          "GPU process haven't connected with the parent process yet"
+          "when creating VR process.");
+      return false;
+    }
+
     mVRChild = MakeUnique<VRChild>(this);
 
     DebugOnly<bool> rv =
@@ -159,10 +167,6 @@ void VRProcessParent::InitAfterConnect(bool aSucceeded) {
     }
 
     // Make vr-gpu process connection
-    GPUChild* gpuChild = GPUProcessManager::Get()->GetGPUChild();
-    // Add logs for Bug 1565000 to figure out why gpuChild can't be access.
-    MOZ_RELEASE_ASSERT(gpuChild, "gpuChild is null.");
-
     Endpoint<PVRGPUChild> vrGPUBridge;
     VRProcessManager* vpm = VRProcessManager::Get();
     DebugOnly<bool> opened =
@@ -171,6 +175,8 @@ void VRProcessParent::InitAfterConnect(bool aSucceeded) {
 
     Unused << gpuChild->SendInitVR(std::move(vrGPUBridge));
   }
+
+  return true;
 }
 
 void VRProcessParent::KillHard(const char* aReason) {

gfx/vr/ipc/VRProcessParent.h

@@ -66,7 +66,7 @@ class VRProcessParent final : public mozilla::ipc::GeckoChildProcessHost {
 
   DISALLOW_COPY_AND_ASSIGN(VRProcessParent);
 
-  void InitAfterConnect(bool aSucceeded);
+  bool InitAfterConnect(bool aSucceeded);
   void KillHard(const char* aReason);
 
   UniquePtr<VRChild> mVRChild;