Bug 1062654 - Part 4: Fix Link/Unlink Apple video frameworks cycle. r=rillian

Prefer VideoToolbox when HW acceleration is available. Otherwise use VDA when available

content/media/fmp4/MP4Decoder.cpp

@@ -21,9 +21,7 @@
 #include "FFmpegRuntimeLinker.h"
 #endif
 #ifdef MOZ_APPLEMEDIA
-#include "apple/AppleVDALinker.h"
-#include "apple/AppleCMLinker.h"
-#include "apple/AppleVTLinker.h"
+#include "apple/AppleDecoderModule.h"
 #endif
 
 namespace mozilla {
@@ -152,12 +150,7 @@ IsAppleAvailable()
     // Disabled by preference.
     return false;
   }
-  // Attempt to load the required frameworks.
-  bool haveVDA = AppleVDALinker::Link();
-  bool haveCoreMedia = AppleCMLinker::Link();
-  bool haveVideoToolbox = AppleVTLinker::Link();
-
-  return haveVDA || (haveCoreMedia && haveVideoToolbox);
+  return NS_SUCCEEDED(AppleDecoderModule::CanDecode());
 #endif
 }
 

content/media/fmp4/apple/AppleCMLinker.cpp

@@ -92,6 +92,7 @@ AppleCMLinker::Unlink()
     LOG("Unlinking CoreMedia framework.");
     dlclose(sLink);
     sLink = nullptr;
+    sLinkStatus = LinkStatus_INIT;
   }
 }
 

content/media/fmp4/apple/AppleDecoderModule.cpp

@@ -16,8 +16,11 @@
 
 namespace mozilla {
 
+bool AppleDecoderModule::sInitialized = false;
 bool AppleDecoderModule::sIsVTAvailable = false;
+bool AppleDecoderModule::sIsVTHWAvailable = false;
 bool AppleDecoderModule::sIsVDAAvailable = false;
+bool AppleDecoderModule::sForceVDA = false;
 
 AppleDecoderModule::AppleDecoderModule()
 {
@@ -33,7 +36,9 @@ AppleDecoderModule::Init()
 {
   MOZ_ASSERT(NS_IsMainThread(), "Must be on main thread.");
 
-  if (!Preferences::GetBool("media.apple.mp4.enabled", false)) {
+  sForceVDA = Preferences::GetBool("media.apple.forcevda", false);
+
+  if (sInitialized) {
     return;
   }
 
@@ -45,18 +50,72 @@ AppleDecoderModule::Init()
   // dlopen VideoToolbox.framework if it's available.
   // We must link both CM and VideoToolbox framework to allow for proper
   // paired Link/Unlink calls
-  sIsVTAvailable = AppleVTLinker::Link() && haveCoreMedia;
+  bool haveVideoToolbox = AppleVTLinker::Link();
+  sIsVTAvailable = haveCoreMedia && haveVideoToolbox;
+
+  sIsVTHWAvailable = AppleVTLinker::skPropHWAccel != nullptr;
+
+  if (sIsVDAAvailable) {
+    AppleVDALinker::Unlink();
+  }
+  if (sIsVTAvailable) {
+    AppleVTLinker::Unlink();
+    AppleCMLinker::Unlink();
+  }
+  sInitialized = true;
 }
 
+class InitTask : public nsRunnable {
+public:
+  NS_IMETHOD Run() MOZ_OVERRIDE {
+    MOZ_ASSERT(NS_IsMainThread(), "Must be on main thread.");
+    AppleDecoderModule::Init();
+    return NS_OK;
+  }
+};
+
+/* static */
+nsresult
+AppleDecoderModule::CanDecode()
+{
+  if (!sInitialized) {
+    if (NS_IsMainThread()) {
+      Init();
+    } else {
+      nsRefPtr<nsIRunnable> task(new InitTask());
+      NS_DispatchToMainThread(task, NS_DISPATCH_SYNC);
+    }
+  }
+
+  return (sIsVDAAvailable || sIsVTAvailable) ? NS_OK : NS_ERROR_NO_INTERFACE;
+}
+
+class LinkTask : public nsRunnable {
+public:
+  NS_IMETHOD Run() MOZ_OVERRIDE {
+    MOZ_ASSERT(NS_IsMainThread(), "Must be on main thread.");
+    MOZ_ASSERT(AppleDecoderModule::sInitialized);
+    if (AppleDecoderModule::sIsVDAAvailable) {
+      AppleVDALinker::Link();
+    }
+    if (AppleDecoderModule::sIsVTAvailable) {
+      AppleVTLinker::Link();
+      AppleCMLinker::Link();
+    }
+    return NS_OK;
+  }
+};
+
 nsresult
 AppleDecoderModule::Startup()
 {
-  // We don't have any per-instance initialization to do.
-  // Check whether ::Init() above succeeded to know if
-  // we're functional.
   if (!sIsVDAAvailable && !sIsVTAvailable) {
     return NS_ERROR_FAILURE;
   }
+
+  nsRefPtr<nsIRunnable> task(new LinkTask());
+  NS_DispatchToMainThread(task, NS_DISPATCH_SYNC);
+
   return NS_OK;
 }
 
@@ -64,9 +123,14 @@ class UnlinkTask : public nsRunnable {
 public:
   NS_IMETHOD Run() MOZ_OVERRIDE {
     MOZ_ASSERT(NS_IsMainThread(), "Must be on main thread.");
-    AppleVDALinker::Unlink();
-    AppleVTLinker::Unlink();
-    AppleCMLinker::Unlink();
+    MOZ_ASSERT(AppleDecoderModule::sInitialized);
+    if (AppleDecoderModule::sIsVDAAvailable) {
+      AppleVDALinker::Unlink();
+    }
+    if (AppleDecoderModule::sIsVTAvailable) {
+      AppleVTLinker::Unlink();
+      AppleCMLinker::Unlink();
+    }
     return NS_OK;
   }
 };
@@ -88,7 +152,7 @@ AppleDecoderModule::CreateH264Decoder(const mp4_demuxer::VideoDecoderConfig& aCo
 {
   nsRefPtr<MediaDataDecoder> decoder;
 
-  if (sIsVDAAvailable) {
+  if (sIsVDAAvailable && (!sIsVTHWAvailable || sForceVDA)) {
     decoder =
       AppleVDADecoder::CreateVDADecoder(aConfig,
                                         aVideoTaskQueue,

content/media/fmp4/apple/AppleDecoderModule.h

@@ -41,9 +41,18 @@ public:
   virtual bool SupportsAudioMimeType(const char* aMimeType) MOZ_OVERRIDE;
 
   static void Init();
+  static nsresult CanDecode();
+
 private:
+  friend class InitTask;
+  friend class LinkTask;
+  friend class UnlinkTask;
+
+  static bool sInitialized;
   static bool sIsVTAvailable;
+  static bool sIsVTHWAvailable;
   static bool sIsVDAAvailable;
+  static bool sForceVDA;
 };
 
 } // namespace mozilla

content/media/fmp4/apple/AppleVDALinker.cpp

@@ -101,6 +101,7 @@ AppleVDALinker::Unlink()
     skPropHeight = nullptr;
     skPropSourceFormat = nullptr;
     skPropAVCCData = nullptr;
+    sLinkStatus = LinkStatus_INIT;
   }
 }
 

content/media/fmp4/apple/AppleVTLinker.cpp

@@ -89,6 +89,7 @@ AppleVTLinker::Unlink()
     dlclose(sLink);
     sLink = nullptr;
     skPropHWAccel = nullptr;
+    sLinkStatus = LinkStatus_INIT;
   }
 }