[RFC PATCH 6/9] dsnoop: The stop threshold was not implemented correctly

Mark Hills mark at xwax.org
Fri Jun 12 11:55:27 CEST 2020


The previous implementation would mean that stop_threshold behaved
erratically. The intent is to detect that the buffer is too full,
and stop.

In practice, I don't think this was a bug in practice for applications
which don't adjust the stop_threshold. The line above catches those cases.
---
 src/pcm/pcm_dsnoop.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pcm/pcm_dsnoop.c b/src/pcm/pcm_dsnoop.c
index c64df381..790d944c 100644
--- a/src/pcm/pcm_dsnoop.c
+++ b/src/pcm/pcm_dsnoop.c
@@ -165,7 +165,7 @@ static int snd_pcm_dsnoop_sync_ptr(snd_pcm_t *pcm)
 	// printf("sync ptr diff = %li\n", diff);
 	if (pcm->stop_threshold >= pcm->boundary)	/* don't care */
 		return 0;
-	if ((avail = snd_pcm_mmap_capture_hw_avail(pcm)) >= pcm->stop_threshold) {
+	if ((avail = snd_pcm_mmap_capture_avail(pcm)) >= pcm->stop_threshold) {
 		gettimestamp(&dsnoop->trigger_tstamp, pcm->tstamp_type);
 		dsnoop->state = SND_PCM_STATE_XRUN;
 		dsnoop->avail_max = avail;
-- 
2.17.5



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