Modified: trunk/Source/WebCore/ChangeLog (283684 => 283685)
--- trunk/Source/WebCore/ChangeLog 2021-10-07 00:32:40 UTC (rev 283684)
+++ trunk/Source/WebCore/ChangeLog 2021-10-07 00:43:09 UTC (rev 283685)
@@ -1,3 +1,28 @@
+2021-10-06 Jean-Yves Avenard <[email protected]>
+
+ Have SourceBufferPrivateAVJObjC use WorkQueue instead of dispatch_async
+ https://bugs.webkit.org/show_bug.cgi?id=230881
+ rdar://83429276
+
+ This change is twofold:
+ 1- dispatch_async takes an objective-C block which doesn't support C++ move
+ semantics. As such the lambda would be copied including the captured variables.
+ When use with a non-thread safe refcounted object it could lead to a race
+ on the refcount which would result in a leak.
+ By using a WorkQueue instead, we avoid the above problem.
+ 2- We want to unify in the media code how threads are created and task
+ dispatched: WorkQueue is a nice solution.
+
+ Reviewed by Chris Dumez.
+
+ No observable difference.
+
+ * platform/graphics/avfoundation/objc/SourceBufferPrivateAVFObjC.h:
+ * platform/graphics/avfoundation/objc/SourceBufferPrivateAVFObjC.mm:
+ (WebCore::SourceBufferPrivateAVFObjC::SourceBufferPrivateAVFObjC):
+ (WebCore::SourceBufferPrivateAVFObjC::append):
+ (WebCore::SourceBufferPrivateAVFObjC::resetParserState):
+
2021-10-06 Tyler Wilcock <[email protected]>
AX: Make AccessibilityObjectInterface::contents return-by-value instead of return-by-out-parameter
Modified: trunk/Source/WebCore/platform/graphics/avfoundation/objc/SourceBufferPrivateAVFObjC.h (283684 => 283685)
--- trunk/Source/WebCore/platform/graphics/avfoundation/objc/SourceBufferPrivateAVFObjC.h 2021-10-07 00:32:40 UTC (rev 283684)
+++ trunk/Source/WebCore/platform/graphics/avfoundation/objc/SourceBufferPrivateAVFObjC.h 2021-10-07 00:43:09 UTC (rev 283685)
@@ -56,6 +56,10 @@
typedef struct opaqueCMSampleBuffer *CMSampleBufferRef;
typedef const struct opaqueCMFormatDescription *CMFormatDescriptionRef;
+namespace WTF {
+class WorkQueue;
+}
+
namespace WebCore {
class CDMInstance;
@@ -206,7 +210,7 @@
RetainPtr<NSError> m_hdcpError;
Box<BinarySemaphore> m_hasSessionSemaphore;
Box<Semaphore> m_abortSemaphore;
- OSObjectPtr<dispatch_group_t> m_isAppendingGroup;
+ const Ref<WTF::WorkQueue> m_appendQueue;
RefPtr<WebCoreDecompressionSession> m_decompressionSession;
MediaSourcePrivateAVFObjC* m_mediaSource;
Modified: trunk/Source/WebCore/platform/graphics/avfoundation/objc/SourceBufferPrivateAVFObjC.mm (283684 => 283685)
--- trunk/Source/WebCore/platform/graphics/avfoundation/objc/SourceBufferPrivateAVFObjC.mm 2021-10-07 00:32:40 UTC (rev 283684)
+++ trunk/Source/WebCore/platform/graphics/avfoundation/objc/SourceBufferPrivateAVFObjC.mm 2021-10-07 00:43:09 UTC (rev 283685)
@@ -60,6 +60,7 @@
#import <wtf/SoftLinking.h>
#import <wtf/WTFSemaphore.h>
#import <wtf/WeakPtr.h>
+#import <wtf/WorkQueue.h>
#import <wtf/text/AtomString.h>
#import <wtf/text/CString.h>
#import <wtf/text/StringToIntegerConversion.h>
@@ -304,7 +305,7 @@
SourceBufferPrivateAVFObjC::SourceBufferPrivateAVFObjC(MediaSourcePrivateAVFObjC* parent, Ref<SourceBufferParser>&& parser)
: m_parser(WTFMove(parser))
, m_errorListener(adoptNS([[WebAVSampleBufferErrorListener alloc] initWithParent:makeWeakPtr(*this)]))
- , m_isAppendingGroup(adoptOSObject(dispatch_group_create()))
+ , m_appendQueue(WorkQueue::create("SourceBufferPrivateAVFObjC data parser queue"))
, m_mediaSource(parent)
, m_mapID(nextMapID())
#if !RELEASE_LOG_DISABLED
@@ -562,16 +563,6 @@
UNUSED_PARAM(hasSessionSemaphore);
}
-static dispatch_queue_t globalDataParserQueue()
-{
- static dispatch_queue_t globalQueue;
- static dispatch_once_t onceToken;
- dispatch_once(&onceToken, ^{
- globalQueue = dispatch_queue_create("SourceBufferPrivateAVFObjC data parser queue", DISPATCH_QUEUE_CONCURRENT);
- });
- return globalQueue;
-}
-
void SourceBufferPrivateAVFObjC::append(Ref<SharedBuffer>&& data)
{
ALWAYS_LOG(LOGIDENTIFIER, "data length = ", data->size());
@@ -646,9 +637,8 @@
});
m_parsingSucceeded = true;
- dispatch_group_enter(m_isAppendingGroup.get());
- dispatch_async(globalDataParserQueue(), [data = "" weakThis = m_appendWeakFactory.createWeakPtr(*this), parser = m_parser, isAppendingGroup = m_isAppendingGroup, abortCalled = m_abortCalled]() mutable {
+ m_appendQueue->dispatch([data = "" weakThis = m_appendWeakFactory.createWeakPtr(*this), parser = m_parser, abortCalled = m_abortCalled]() mutable {
parser->appendData(WTFMove(data), [weakThis = WTFMove(weakThis), abortCalled]() mutable {
callOnMainThread([weakThis = WTFMove(weakThis), abortCalled] {
if (!weakThis || abortCalled != weakThis->m_abortCalled)
@@ -662,7 +652,6 @@
weakThis->appendCompleted();
});
});
- dispatch_group_leave(isAppendingGroup.get());
});
}
@@ -708,7 +697,8 @@
{
ALWAYS_LOG(LOGIDENTIFIER);
- dispatch_group_wait(m_isAppendingGroup.get(), DISPATCH_TIME_FOREVER);
+ // Wait until all tasks in the workqueue have run.
+ m_appendQueue->dispatchSync([] { });
m_mediaSamples.clear();
m_hasPendingAppendCompletedCallback = false;
m_processingInitializationSegment = false;
