Am 10.09.20 um 13:17 schrieb zhou qi: > From e8c2e283f0954de255a32ea70d577d5e61992399 Mon Sep 17 00:00:00 2001 > From: Qi Zhou <atm...@outlook.com> > Date: Thu, 10 Sep 2020 19:09:29 +0800 > Subject: [PATCH] Fix video playback slowdown when spice client no audio > enabled > > You will get video playback slowdown on the following cases > > 1. use official spice client with audio channel disabled, use > --spice-disable-audio > option > 2. thirtpart client doesn't implement audio channel > > ref: > https://github.com/qemu/qemu/commit/fb35c2cec58985f0b8d2733f1b91927542eeb3fd > Signed-off-by: Qi Zhou <atm...@outlook.com> > --- > audio/audio.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/audio/audio.c b/audio/audio.c > index ce8c6dec5f..50febe190f 100644 > --- a/audio/audio.c > +++ b/audio/audio.c > @@ -1091,7 +1091,11 @@ static size_t audio_pcm_hw_run_out(HWVoiceOut *hw, > size_t live) > while (live) { > size_t size, decr, proc; > void *buf = hw->pcm_ops->get_buffer_out(hw, &size); > - if (!buf || size == 0) { > + > + if (!buf) { > + hw->mix_buf->pos = (hw->mix_buf->pos + live) % hw->mix_buf->size; > + return clipped + live; > + } else if ( size == 0) { > break; > } >
Hello Qi, your patch breaks audio playback with the dsoundaudio backend. I suggest you make the following changes: - Test for size == 0 first and leave the loop in that case. - For buf == NULL drop size bytes. Don't leave the loop with break or return. - Verify all audio backends adhere to the new rules and fix them if necessary. It's quite possible no patches are needed. - Rate limit the audio stream in function line_out_get_buffer() in audio/spiceaudio.c for the noaudio case too. Have a look at audio/spiceaudio.c at version v4.1.0. The code there was correct. Please don't forget to run scripts/checkpatch.pl on your next patches and don't forget to CC the maintainer. With best regards, Volker
