diff options
author | Takashi Iwai <tiwai@suse.de> | 2005-05-31 12:35:31 (GMT) |
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committer | Jaroslav Kysela <perex@suse.cz> | 2005-06-22 10:27:53 (GMT) |
commit | 21cb2a2ec5818cbba01bcb7f24388670322c77f9 (patch) | |
tree | abd491e1b613f200970359546185619228d3ec02 /sound | |
parent | ce43fbaececc82196d321671159483b3287de128 (diff) | |
download | linux-fsl-qoriq-21cb2a2ec5818cbba01bcb7f24388670322c77f9.tar.xz |
[ALSA] Fix races between PCM drain and other ops
PCM Midlevel
Fix semaphore races between PCM drain and other ops.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound')
-rw-r--r-- | sound/core/pcm_native.c | 70 |
1 files changed, 36 insertions, 34 deletions
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index 4e58241..10c2c98 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -1368,43 +1368,32 @@ static int snd_pcm_drain(snd_pcm_substream_t *substream) if (runtime->status->state == SNDRV_PCM_STATE_OPEN) return -EBADFD; - down_read(&snd_pcm_link_rwsem); snd_power_lock(card); if (runtime->status->state == SNDRV_PCM_STATE_SUSPENDED) { result = snd_power_wait(card, SNDRV_CTL_POWER_D0, substream->ffile); - if (result < 0) - goto _unlock; + if (result < 0) { + snd_power_unlock(card); + return result; + } } /* allocate temporary record for drain sync */ + down_read(&snd_pcm_link_rwsem); if (snd_pcm_stream_linked(substream)) { drec = kmalloc(substream->group->count * sizeof(*drec), GFP_KERNEL); if (! drec) { - result = -ENOMEM; - goto _unlock; + up_read(&snd_pcm_link_rwsem); + snd_power_unlock(card); + return -ENOMEM; } } else drec = &drec_tmp; - snd_pcm_stream_lock_irq(substream); - /* resume pause */ - if (runtime->status->state == SNDRV_PCM_STATE_PAUSED) - snd_pcm_pause(substream, 0); - - /* pre-start/stop - all running streams are changed to DRAINING state */ - result = snd_pcm_action(&snd_pcm_action_drain_init, substream, 0); - if (result < 0) - goto _end; - - /* check streams with PLAYBACK & DRAINING */ + /* count only playback streams */ num_drecs = 0; snd_pcm_group_for_each(pos, substream) { snd_pcm_substream_t *s = snd_pcm_group_substream_entry(pos); runtime = s->runtime; - if (runtime->status->state != SNDRV_PCM_STATE_DRAINING) { - runtime->status->state = SNDRV_PCM_STATE_SETUP; - continue; - } if (s->stream == SNDRV_PCM_STREAM_PLAYBACK) { d = &drec[num_drecs++]; d->substream = s; @@ -1418,9 +1407,21 @@ static int snd_pcm_drain(snd_pcm_substream_t *substream) runtime->stop_threshold = runtime->buffer_size; } } - + up_read(&snd_pcm_link_rwsem); if (! num_drecs) - goto _end; + goto _error; + + snd_pcm_stream_lock_irq(substream); + /* resume pause */ + if (runtime->status->state == SNDRV_PCM_STATE_PAUSED) + snd_pcm_pause(substream, 0); + + /* pre-start/stop - all running streams are changed to DRAINING state */ + result = snd_pcm_action(&snd_pcm_action_drain_init, substream, 0); + if (result < 0) { + snd_pcm_stream_unlock_irq(substream); + goto _error; + } for (;;) { long tout; @@ -1428,6 +1429,15 @@ static int snd_pcm_drain(snd_pcm_substream_t *substream) result = -ERESTARTSYS; break; } + /* all finished? */ + for (i = 0; i < num_drecs; i++) { + runtime = drec[i].substream->runtime; + if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) + break; + } + if (i == num_drecs) + break; /* yes, all drained */ + set_current_state(TASK_INTERRUPTIBLE); snd_pcm_stream_unlock_irq(substream); snd_power_unlock(card); @@ -1444,15 +1454,11 @@ static int snd_pcm_drain(snd_pcm_substream_t *substream) } break; } - /* all finished? */ - for (i = 0; i < num_drecs; i++) { - runtime = drec[i].substream->runtime; - if (runtime->status->state == SNDRV_PCM_STATE_DRAINING) - break; - } - if (i == num_drecs) - break; } + + snd_pcm_stream_unlock_irq(substream); + + _error: for (i = 0; i < num_drecs; i++) { d = &drec[i]; runtime = d->substream->runtime; @@ -1460,13 +1466,9 @@ static int snd_pcm_drain(snd_pcm_substream_t *substream) runtime->stop_threshold = d->stop_threshold; } - _end: - snd_pcm_stream_unlock_irq(substream); if (drec != &drec_tmp) kfree(drec); - _unlock: snd_power_unlock(card); - up_read(&snd_pcm_link_rwsem); return result; } |