From 77de4f7263e376e55b521514e02132b5f987d940 Mon Sep 17 00:00:00 2001
From: Coroiu Cristina <ccoroiu@mozilla.com>
Date: Sat, 26 Jan 2019 01:46:32 +0200
Subject: [PATCH] Backed out changeset e0034670b26a (bug 1514417) as requested
 by daoshengmu

---
 gfx/vr/gfxVRExternal.cpp     | 8 ++------
 gfx/vr/gfxVRExternal.h       | 1 -
 gfx/vr/service/VRService.cpp | 7 -------
 gfx/vr/service/VRService.h   | 3 ---
 4 files changed, 2 insertions(+), 17 deletions(-)

diff --git a/gfx/vr/gfxVRExternal.cpp b/gfx/vr/gfxVRExternal.cpp
index a4f006f61ddf..b982a84b8c0b 100644
--- a/gfx/vr/gfxVRExternal.cpp
+++ b/gfx/vr/gfxVRExternal.cpp
@@ -426,8 +426,8 @@ VRSystemManagerExternal::VRSystemManagerExternal(
     VRExternalShmem* aAPIShmem /* = nullptr*/)
     : mExternalShmem(aAPIShmem)
 #if !defined(MOZ_WIDGET_ANDROID)
-    , mMutex("VRSystemManagerExternal::mMutex")
-    , mSameProcess(aAPIShmem != nullptr)
+      ,
+      mSameProcess(aAPIShmem != nullptr)
 #endif
 {
 #if defined(XP_MACOSX)
@@ -844,10 +844,6 @@ void VRSystemManagerExternal::PushState(VRBrowserState* aBrowserState,
       pthread_mutex_unlock((pthread_mutex_t*)&(mExternalShmem->browserMutex));
     }
 #else
-    // We need this MutexAutoLock to avoid mAPIShmem happens deadlock issue
-    // when both of VRService and VRSubmitFrame threads are writing/reading
-    // it from the memory.
-    MutexAutoLock lock(mMutex);
     mExternalShmem->browserGenerationA++;
     memcpy((void*)&(mExternalShmem->browserState), (void*)aBrowserState,
            sizeof(VRBrowserState));
diff --git a/gfx/vr/gfxVRExternal.h b/gfx/vr/gfxVRExternal.h
index 1b0429fefbb1..d129350e27bc 100644
--- a/gfx/vr/gfxVRExternal.h
+++ b/gfx/vr/gfxVRExternal.h
@@ -134,7 +134,6 @@ class VRSystemManagerExternal : public VRSystemManager {
 
   volatile VRExternalShmem* mExternalShmem;
 #if !defined(MOZ_WIDGET_ANDROID)
-  Mutex mMutex;
   bool mSameProcess;
 #endif
   TimeStamp mEarliestRestartTime;
diff --git a/gfx/vr/service/VRService.cpp b/gfx/vr/service/VRService.cpp
index 1b8664c99b0b..b622a460e9f1 100644
--- a/gfx/vr/service/VRService.cpp
+++ b/gfx/vr/service/VRService.cpp
@@ -68,9 +68,6 @@ VRService::VRService()
       mTargetShmemFile(0),
       mLastHapticState{},
       mFrameStartTime{},
-#if !defined(MOZ_WIDGET_ANDROID)
-      mMutex("VRService::mMutex"),
-#endif
       mVRProcessEnabled(gfxPrefs::VRProcessEnabled()) {
   // When we have the VR process, we map the memory
   // of mAPIShmem from GPU process.
@@ -459,10 +456,6 @@ void VRService::PullState(mozilla::gfx::VRBrowserState& aState) {
     pthread_mutex_unlock((pthread_mutex_t*)&(mExternalShmem->browserMutex));
   }
 #else
-  // We need this MutexAutoLock to avoid mAPIShmem happens deadlock issue
-  // when both of VRService and VRSubmitFrame threads are writing/reading
-  // it from the memory.
-  MutexAutoLock lock(mMutex);
   VRExternalShmem tmp;
   if (mAPIShmem->browserGenerationA != mBrowserGeneration) {
     memcpy(&tmp, mAPIShmem, sizeof(VRExternalShmem));
diff --git a/gfx/vr/service/VRService.h b/gfx/vr/service/VRService.h
index 1a6f955d8259..32eddab50c1d 100644
--- a/gfx/vr/service/VRService.h
+++ b/gfx/vr/service/VRService.h
@@ -63,9 +63,6 @@ class VRService {
   base::ProcessHandle mTargetShmemFile;
   VRHapticState mLastHapticState[kVRHapticsMaxCount];
   TimeStamp mFrameStartTime[kVRFrameTimingHistoryDepth];
-#if !defined(MOZ_WIDGET_ANDROID)
-  Mutex mMutex;
-#endif
   // We store the value of gfxPrefs::VRProcessEnabled() in mVRProcessEnabled.
   // This allows us to read the value in the VRService destructor, after
   // gfxPrefs has been shut down.  We should investigate why gfxPrefs