From 3dffe95932ffb4d062728ce9885da55a4b396086 Mon Sep 17 00:00:00 2001
From: Robert O'Callahan <robert@ocallahan.org>
Date: Wed, 4 Sep 2013 23:13:06 +1200
Subject: [PATCH] Bug 904926. Remove unnecessary lock. r=cpearce

--HG--
extra : rebase_source : 0088907b65ff3ce2e1f15b2bb1b5e0cdb7126f24
---
 content/media/MediaDecoder.cpp |  6 ++----
 content/media/MediaDecoder.h   | 18 ++++++++++--------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/content/media/MediaDecoder.cpp b/content/media/MediaDecoder.cpp
index 11457dcd96e..c1ff95aa917 100644
--- a/content/media/MediaDecoder.cpp
+++ b/content/media/MediaDecoder.cpp
@@ -362,7 +362,6 @@ MediaDecoder::MediaDecoder() :
   mInitialVolume(0.0),
   mInitialPlaybackRate(1.0),
   mInitialPreservesPitch(true),
-  mRequestedSeekTime(-1.0),
   mDuration(-1),
   mTransportSeekable(true),
   mMediaSeekable(true),
@@ -372,6 +371,7 @@ MediaDecoder::MediaDecoder() :
   mIsExitingDormant(false),
   mPlayState(PLAY_STATE_PAUSED),
   mNextState(PLAY_STATE_PAUSED),
+  mRequestedSeekTime(-1.0),
   mCalledResourceLoaded(false),
   mIgnoreProgressData(false),
   mInfiniteStream(false),
@@ -708,8 +708,7 @@ bool
 MediaDecoder::IsDataCachedToEndOfResource()
 {
   NS_ASSERTION(!mShuttingDown, "Don't call during shutdown!");
-  GetReentrantMonitor().AssertCurrentThreadIn();
-
+  ReentrantMonitorAutoEnter mon(GetReentrantMonitor());
   return (mResource &&
           mResource->IsDataCachedToEndOfResource(mDecoderPosition));
 }
@@ -755,7 +754,6 @@ void MediaDecoder::MetadataLoaded(int aChannels, int aRate, bool aHasAudio, bool
 
   // Only inform the element of FirstFrameLoaded if not doing a load() in order
   // to fulfill a seek, otherwise we'll get multiple loadedfirstframe events.
-  ReentrantMonitorAutoEnter mon(GetReentrantMonitor());
   bool notifyResourceIsLoaded = !mCalledResourceLoaded &&
                                 IsDataCachedToEndOfResource();
   if (mOwner) {
diff --git a/content/media/MediaDecoder.h b/content/media/MediaDecoder.h
index 78ea87dcfb3..65d62454c4a 100644
--- a/content/media/MediaDecoder.h
+++ b/content/media/MediaDecoder.h
@@ -692,7 +692,7 @@ public:
   // Call on the main thread only.
   void FirstFrameLoaded();
 
-  // Returns true if the resource has been loaded. Must be in monitor.
+  // Returns true if the resource has been loaded. Acquires the monitor.
   // Call from any thread.
   virtual bool IsDataCachedToEndOfResource();
 
@@ -946,13 +946,6 @@ public:
   double mInitialPlaybackRate;
   bool mInitialPreservesPitch;
 
-  // Position to seek to when the seek notification is received by the
-  // decode thread. Written by the main thread and read via the
-  // decode thread. Synchronised using mReentrantMonitor. If the
-  // value is negative then no seek has been requested. When a seek is
-  // started this is reset to negative.
-  double mRequestedSeekTime;
-
   // Duration of the media resource. Set to -1 if unknown.
   // Set when the metadata is loaded. Accessed on the main thread
   // only.
@@ -1055,6 +1048,15 @@ public:
   // This can only be PLAY_STATE_PAUSED or PLAY_STATE_PLAYING.
   PlayState mNextState;
 
+  // Position to seek to when the seek notification is received by the
+  // decode thread.
+  // This can only be changed on the main thread while holding the decoder
+  // monitor. Thus, it can be safely read while holding the decoder monitor
+  // OR on the main thread.
+  // If the value is negative then no seek has been requested. When a seek is
+  // started this is reset to negative.
+  double mRequestedSeekTime;
+
   // True when we have fully loaded the resource and reported that
   // to the element (i.e. reached NETWORK_LOADED state).
   // Accessed on the main thread only.