audio/hda: detect output buffer overruns

If some event caused some larger playback hickup the fine-grained timer
adjust isn't able to recover.  Use a buffer overruns as indicator for
that.  Reset timer adjust logic in case we detected one.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20180622111200.30561-5-kraxel@redhat.com
This commit is contained in:
Gerd Hoffmann 2018-06-22 13:11:59 +02:00
parent 8ced066923
commit 4501ee16c7
2 changed files with 10 additions and 0 deletions

View file

@ -325,6 +325,15 @@ static void hda_audio_output_cb(void *opaque, int avail)
int64_t to_transfer = audio_MIN(wpos - rpos, avail);
if (wpos - rpos == B_SIZE) {
/* drop buffer, reset timer adjust */
st->rpos = 0;
st->wpos = 0;
st->buft_start = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
trace_hda_audio_overrun(st->node->name);
return;
}
hda_timer_sync_adjust(st, (wpos - rpos) - to_transfer - (B_SIZE >> 1));
while (to_transfer) {

View file

@ -22,3 +22,4 @@ milkymist_ac97_out_cb_transferred(int transferred) "transferred %d"
hda_audio_running(const char *stream, int nr, bool running) "st %s, nr %d, run %d"
hda_audio_format(const char *stream, int chan, const char *fmt, int freq) "st %s, %d x %s @ %d Hz"
hda_audio_adjust(const char *stream, int pos) "st %s, pos %d"
hda_audio_overrun(const char *stream) "st %s"