Changeset 279500 in webkit

Timestamp:

Jul 2, 2021, 12:09:52 AM (5 years ago)

Author:

youenn@apple.com

Message:

Make LocalSampleBufferDisplayLayer::requestNotificationWhenReadyForVideoData hop to main thread before hopping to processing thread
​https://bugs.webkit.org/show_bug.cgi?id=227444
<rdar://79413368>

Reviewed by Chris Dumez.

It is safer to hop to main thread in requestNotificationWhenReadyForVideoData callback so that we can check weakThis safely.
When in main thread, hop to processing thread if LocalSampleBufferDisplayLayer is alive.

• platform/graphics/avfoundation/objc/LocalSampleBufferDisplayLayer.mm:

(WebCore::LocalSampleBufferDisplayLayer::~LocalSampleBufferDisplayLayer):
(WebCore::LocalSampleBufferDisplayLayer::requestNotificationWhenReadyForVideoData):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/avfoundation/objc/LocalSampleBufferDisplayLayer.mm (modified) (3 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2021-07-02  Youenn Fablet  <youenn@apple.com>
+
+        Make LocalSampleBufferDisplayLayer::requestNotificationWhenReadyForVideoData hop to main thread before hopping to processing thread
+        https://bugs.webkit.org/show_bug.cgi?id=227444
+        <rdar://79413368>
+
+        Reviewed by Chris Dumez.
+
+        It is safer to hop to main thread in requestNotificationWhenReadyForVideoData callback so that we can check weakThis safely.
+        When in main thread, hop to processing thread if LocalSampleBufferDisplayLayer is alive.
+
+        * platform/graphics/avfoundation/objc/LocalSampleBufferDisplayLayer.mm:
+        (WebCore::LocalSampleBufferDisplayLayer::~LocalSampleBufferDisplayLayer):
+        (WebCore::LocalSampleBufferDisplayLayer::requestNotificationWhenReadyForVideoData):
+
 2021-06-30  Darin Adler  <darin@apple.com>
 

trunk/Source/WebCore/platform/graphics/avfoundation/objc/LocalSampleBufferDisplayLayer.mm

@@ -157 +157 @@
 #endif
 {
+    ASSERT(isMainThread());
 }
 
@@ -187 +188 @@
 LocalSampleBufferDisplayLayer::~LocalSampleBufferDisplayLayer()
 {
+    ASSERT(isMainThread());
+
     m_processingQueue->dispatchSync([] { });
 
@@ -392 +395 @@
 {
     auto weakThis = makeWeakPtr(*this);
-    [m_sampleBufferDisplayLayer requestMediaDataWhenReadyOnQueue:m_processingQueue->dispatchQueue() usingBlock:^{
+    [m_sampleBufferDisplayLayer requestMediaDataWhenReadyOnQueue:dispatch_get_main_queue() usingBlock:^{
         if (!weakThis)
             return;
 
-        [m_sampleBufferDisplayLayer stopRequestingMediaData];
-
-        while (!m_pendingVideoSampleQueue.isEmpty()) {
-            if (![m_sampleBufferDisplayLayer isReadyForMoreMediaData]) {
-                requestNotificationWhenReadyForVideoData();
-                return;
+        m_processingQueue->dispatch([this] {
+            [m_sampleBufferDisplayLayer stopRequestingMediaData];
+
+            while (!m_pendingVideoSampleQueue.isEmpty()) {
+                if (![m_sampleBufferDisplayLayer isReadyForMoreMediaData]) {
+                    requestNotificationWhenReadyForVideoData();
+                    return;
+                }
+                auto sample = m_pendingVideoSampleQueue.takeFirst();
+                enqueueSampleBuffer(sample);
             }
-            auto sample = m_pendingVideoSampleQueue.takeFirst();
-            enqueueSampleBuffer(sample);
-        }
+        });
     }];
 }