ALSA: pcm: Update the state properly before notification
Some state changes (e.g. snd_pcm_stop()) sets the runtime state after
calling snd_timer_notify(). This is basically racy, since the
notification may wakes up the user even before the state change.
Although the possibility is low, we should set the state before the
notifications.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index ca224fa..dfb5031 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -1052,10 +1052,10 @@
struct snd_pcm_runtime *runtime = substream->runtime;
if (runtime->status->state != state) {
snd_pcm_trigger_tstamp(substream);
+ runtime->status->state = state;
if (substream->timer)
snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MSTOP,
&runtime->trigger_tstamp);
- runtime->status->state = state;
}
wake_up(&runtime->sleep);
wake_up(&runtime->tsleep);
@@ -1204,11 +1204,11 @@
{
struct snd_pcm_runtime *runtime = substream->runtime;
snd_pcm_trigger_tstamp(substream);
+ runtime->status->suspended_state = runtime->status->state;
+ runtime->status->state = SNDRV_PCM_STATE_SUSPENDED;
if (substream->timer)
snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MSUSPEND,
&runtime->trigger_tstamp);
- runtime->status->suspended_state = runtime->status->state;
- runtime->status->state = SNDRV_PCM_STATE_SUSPENDED;
wake_up(&runtime->sleep);
wake_up(&runtime->tsleep);
}
@@ -1311,10 +1311,10 @@
{
struct snd_pcm_runtime *runtime = substream->runtime;
snd_pcm_trigger_tstamp(substream);
+ runtime->status->state = runtime->status->suspended_state;
if (substream->timer)
snd_timer_notify(substream->timer, SNDRV_TIMER_EVENT_MRESUME,
&runtime->trigger_tstamp);
- runtime->status->state = runtime->status->suspended_state;
}
static struct action_ops snd_pcm_action_resume = {
