[GPUProcess] Regression(r268632) Garbage is rendered on speakers when using WebAudio

[Chris Dumez]

garbage is rendered on speakers when using WebAudio and when enabling the GPU Process.

Easily testable with this demo:
https://webaudiodemos.appspot.com/MIDIDrums/index.html

This is a regression from using a CARingBuffer.

[Chris Dumez]

Created attachment 413644 [details]
Patch

[Peng Liu]

Comment on attachment 413644 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=413644&action=review

> Source/WebKit/ChangeLog:14
> +        remain to processed (usually 0). As a result, RemoteAudioDestinationProxy::renderOnRenderingThead()

Good catch! I misunderstood the comment of PushPullFIFO::pull(). The return value of this function is the number of samples *left* in the FIFO, not the number of samples fetched from the FIFO.

> Source/WebKit/WebProcess/GPU/media/RemoteAudioDestinationProxy.cpp:140
>          completionHandler(0, 0);

Not a problem of this patch. But we have to early return here after calling completionHandler().

[Chris Dumez]

Created attachment 413697 [details]
Patch

[EWS]

Committed r269630: <https://trac.webkit.org/changeset/269630>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 413697 [details].

[Radar WebKit Bug Importer]

<rdar://problem/71245599>