Bug 230881 – Have SourceBufferPrivateAVJObjC use WorkQueue instead of dispatch_async

• Status: RESOLVED
• Resolution: FIXED
• Component: Media

[Jean-Yves Avenard [:jya]]

Have SourceBufferPrivateAVJObjC use WorkQueue instead of dispatch_async

[Jean-Yves Avenard [:jya]]

Created attachment 439440 [details]
Patch

Hopefully no error in Windows / Linux, can't compile locally

[Jean-Yves Avenard [:jya]]

Created attachment 439442 [details]
Patch

[Jean-Yves Avenard [:jya]]

Created attachment 439453 [details]
Patch

[Jean-Yves Avenard [:jya]]

rdar://problem/83429276

[Jean-Yves Avenard [:jya]]

*** Bug 230663 has been marked as a duplicate of this bug. ***

[Jean-Yves Avenard [:jya]]

Created attachment 440171 [details]
Patch

Add additional explanation in Changelog

[Chris Dumez]

Comment on attachment 440171 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=440171&action=review

> Source/WTF/wtf/cocoa/WorkQueueCocoa.cpp:59
> +    dispatch_group_enter(m_dispatchGroup.get());

I don't think this is the right level of abstraction and I don't think we want to pay the cost of dispatch_group_enter / dispatch_group_leave for *every* dispatch call, simply to support awaitIdle() at one call site.

If we really wanted to support this, I think we would introduce the concept of group, like in the dispatch API. That said, for this patch, I don't think we need the concept of group or awaitIdle() at all.

> Source/WebCore/platform/graphics/avfoundation/objc/SourceBufferPrivateAVFObjC.mm:700
> +    m_appendQueue->awaitIdle();

Since you have a dedicated queue now, why can't you simply m_appendQueue->dispatchSync() to make sure all previous tasks have completed and hang while waiting?

The previous code was using the concept of group because we were using a shared global queue.

[Jean-Yves Avenard [:jya]]

Created attachment 440328 [details]
Patch

[EWS]

Committed r283685 (242621@main): <https://commits.webkit.org/242621@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 440328 [details].