[alsa-devel] [PATCH] PCM: snd_pcm_dmix_drain() maybe blocked after suspend and resume
After suspend and resume, the alsa driver is stopped. But if alsa-lib run into snd_pcm_dmix_drain(), it need to wait avail >= pcm->stop_threshold, otherwise, it will not exit the loop, so finally it is blocked at poll() of snd_pcm_wait_nocheck(pcm, -1). This patch is to add state check after snd_pcm_wait_nocheck(pcm, -1), if the state is SND_PCM_STATE_SUSPENDED, then return error.
Signed-off-by: Shengjiu Wang shengjiu.wang@freescale.com --- src/pcm/pcm_dmix.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/src/pcm/pcm_dmix.c b/src/pcm/pcm_dmix.c index babde6a..0cc318e 100644 --- a/src/pcm/pcm_dmix.c +++ b/src/pcm/pcm_dmix.c @@ -647,6 +647,12 @@ static int snd_pcm_dmix_drain(snd_pcm_t *pcm) if (dmix->state == SND_PCM_STATE_DRAINING) { snd_pcm_dmix_sync_area(pcm); snd_pcm_wait_nocheck(pcm, -1); + switch (snd_pcm_state(pcm)) { + case SND_PCM_STATE_SUSPENDED: + return -ESTRPIPE; + default: + break; + } snd_pcm_direct_clear_timer_queue(dmix); /* force poll to wait */ } } while (dmix->state == SND_PCM_STATE_DRAINING);
At Mon, 8 Jun 2015 17:38:11 +0800, Shengjiu Wang wrote:
After suspend and resume, the alsa driver is stopped. But if alsa-lib run into snd_pcm_dmix_drain(), it need to wait avail >= pcm->stop_threshold, otherwise, it will not exit the loop, so finally it is blocked at poll() of snd_pcm_wait_nocheck(pcm, -1). This patch is to add state check after snd_pcm_wait_nocheck(pcm, -1), if the state is SND_PCM_STATE_SUSPENDED, then return error.
Signed-off-by: Shengjiu Wang shengjiu.wang@freescale.com
src/pcm/pcm_dmix.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/src/pcm/pcm_dmix.c b/src/pcm/pcm_dmix.c index babde6a..0cc318e 100644 --- a/src/pcm/pcm_dmix.c +++ b/src/pcm/pcm_dmix.c @@ -647,6 +647,12 @@ static int snd_pcm_dmix_drain(snd_pcm_t *pcm) if (dmix->state == SND_PCM_STATE_DRAINING) { snd_pcm_dmix_sync_area(pcm); snd_pcm_wait_nocheck(pcm, -1);
switch (snd_pcm_state(pcm)) {
It's better (shorter) to call snd_pcm_state(dmix->spcm) in this case.
And, I think we should have the check of SND_PCM_STATE_SUSPENDED at the beginning of snd_pcm_dmix_drain() before entering to the loop, too.
Last but not least, the very same bug is present for dshare. Could you fix this together?
thanks,
Takashi
case SND_PCM_STATE_SUSPENDED:return -ESTRPIPE;default:break;} snd_pcm_direct_clear_timer_queue(dmix); /* force poll to wait */-- 1.7.9.5
On Mon, Jun 08, 2015 at 01:31:41PM +0200, Takashi Iwai wrote:
At Mon, 8 Jun 2015 17:38:11 +0800, Shengjiu Wang wrote:
After suspend and resume, the alsa driver is stopped. But if alsa-lib run into snd_pcm_dmix_drain(), it need to wait avail >= pcm->stop_threshold, otherwise, it will not exit the loop, so finally it is blocked at poll() of snd_pcm_wait_nocheck(pcm, -1). This patch is to add state check after snd_pcm_wait_nocheck(pcm, -1), if the state is SND_PCM_STATE_SUSPENDED, then return error.
Signed-off-by: Shengjiu Wang shengjiu.wang@freescale.com
src/pcm/pcm_dmix.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/src/pcm/pcm_dmix.c b/src/pcm/pcm_dmix.c index babde6a..0cc318e 100644 --- a/src/pcm/pcm_dmix.c +++ b/src/pcm/pcm_dmix.c @@ -647,6 +647,12 @@ static int snd_pcm_dmix_drain(snd_pcm_t *pcm) if (dmix->state == SND_PCM_STATE_DRAINING) { snd_pcm_dmix_sync_area(pcm); snd_pcm_wait_nocheck(pcm, -1);
switch (snd_pcm_state(pcm)) {It's better (shorter) to call snd_pcm_state(dmix->spcm) in this case.
And, I think we should have the check of SND_PCM_STATE_SUSPENDED at the beginning of snd_pcm_dmix_drain() before entering to the loop, too.
Last but not least, the very same bug is present for dshare. Could you fix this together?
Ok, I will refine the patch. But one thing I don't understand is that why need to check the SND_PCM_STATE_SUSPENDED before entering the loop, seems check the state in the loop can resolve the issue.
Best regards wang shengjiu
thanks,
Takashi
case SND_PCM_STATE_SUSPENDED:return -ESTRPIPE;default:break;} snd_pcm_direct_clear_timer_queue(dmix); /* force poll to wait */-- 1.7.9.5
At Tue, 9 Jun 2015 10:35:41 +0800, Shengjiu Wang wrote:
On Mon, Jun 08, 2015 at 01:31:41PM +0200, Takashi Iwai wrote:
At Mon, 8 Jun 2015 17:38:11 +0800, Shengjiu Wang wrote:
After suspend and resume, the alsa driver is stopped. But if alsa-lib run into snd_pcm_dmix_drain(), it need to wait avail >= pcm->stop_threshold, otherwise, it will not exit the loop, so finally it is blocked at poll() of snd_pcm_wait_nocheck(pcm, -1). This patch is to add state check after snd_pcm_wait_nocheck(pcm, -1), if the state is SND_PCM_STATE_SUSPENDED, then return error.
Signed-off-by: Shengjiu Wang shengjiu.wang@freescale.com
src/pcm/pcm_dmix.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/src/pcm/pcm_dmix.c b/src/pcm/pcm_dmix.c index babde6a..0cc318e 100644 --- a/src/pcm/pcm_dmix.c +++ b/src/pcm/pcm_dmix.c @@ -647,6 +647,12 @@ static int snd_pcm_dmix_drain(snd_pcm_t *pcm) if (dmix->state == SND_PCM_STATE_DRAINING) { snd_pcm_dmix_sync_area(pcm); snd_pcm_wait_nocheck(pcm, -1);
switch (snd_pcm_state(pcm)) {It's better (shorter) to call snd_pcm_state(dmix->spcm) in this case.
And, I think we should have the check of SND_PCM_STATE_SUSPENDED at the beginning of snd_pcm_dmix_drain() before entering to the loop, too.
Last but not least, the very same bug is present for dshare. Could you fix this together?
Ok, I will refine the patch. But one thing I don't understand is that why need to check the SND_PCM_STATE_SUSPENDED before entering the loop, seems check the state in the loop can resolve the issue.
It's just a minor optimization. The check isn't done at the beginning of the loop but after a few other calls (sync_ptr and sync_area) to be skipped at PM.
Takashi
participants (2)
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Shengjiu Wang -
Takashi Iwai