ALSA: pcm_core: Fix wake_up() optimization
This change fixes the "ALSA: pcm_lib - optimize wake_up() calls for PCM I/O"
commit. New sleeping queue is introduced to separate user space and kernel
space wake_ups. runtime->nowake is renamed to twake (transfer wake).
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index e26fb3c..3bc9bca 100644
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -311,8 +311,9 @@
struct snd_pcm_mmap_control *control;
/* -- locking / scheduling -- */
- unsigned int nowake: 1; /* no wakeup (data-copy in progress) */
- wait_queue_head_t sleep;
+ unsigned int twake: 1; /* do transfer (!poll) wakeup */
+ wait_queue_head_t sleep; /* poll sleep */
+ wait_queue_head_t tsleep; /* transfer sleep */
struct fasync_struct *fasync;
/* -- private section -- */
diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index df57a0e..0d428d0 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -894,6 +894,7 @@
memset((void*)runtime->control, 0, size);
init_waitqueue_head(&runtime->sleep);
+ init_waitqueue_head(&runtime->tsleep);
runtime->status->state = SNDRV_PCM_STATE_OPEN;
diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c
index 5417f7d..e2a817e 100644
--- a/sound/core/pcm_lib.c
+++ b/sound/core/pcm_lib.c
@@ -285,8 +285,8 @@
return -EPIPE;
}
}
- if (!runtime->nowake && avail >= runtime->control->avail_min)
- wake_up(&runtime->sleep);
+ if (avail >= runtime->control->avail_min)
+ wake_up(runtime->twake ? &runtime->tsleep : &runtime->sleep);
return 0;
}
@@ -1692,7 +1692,7 @@
long tout;
init_waitqueue_entry(&wait, current);
- add_wait_queue(&runtime->sleep, &wait);
+ add_wait_queue(&runtime->tsleep, &wait);
for (;;) {
if (signal_pending(current)) {
err = -ERESTARTSYS;
@@ -1735,7 +1735,7 @@
break;
}
_endloop:
- remove_wait_queue(&runtime->sleep, &wait);
+ remove_wait_queue(&runtime->tsleep, &wait);
*availp = avail;
return err;
}
@@ -1794,7 +1794,7 @@
goto _end_unlock;
}
- runtime->nowake = 1;
+ runtime->twake = 1;
while (size > 0) {
snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
snd_pcm_uframes_t avail;
@@ -1816,7 +1816,7 @@
if (frames > cont)
frames = cont;
if (snd_BUG_ON(!frames)) {
- runtime->nowake = 0;
+ runtime->twake = 0;
snd_pcm_stream_unlock_irq(substream);
return -EINVAL;
}
@@ -1855,7 +1855,7 @@
}
}
_end_unlock:
- runtime->nowake = 0;
+ runtime->twake = 0;
if (xfer > 0 && err >= 0)
snd_pcm_update_state(substream, runtime);
snd_pcm_stream_unlock_irq(substream);
@@ -2016,7 +2016,7 @@
goto _end_unlock;
}
- runtime->nowake = 1;
+ runtime->twake = 1;
while (size > 0) {
snd_pcm_uframes_t frames, appl_ptr, appl_ofs;
snd_pcm_uframes_t avail;
@@ -2045,7 +2045,7 @@
if (frames > cont)
frames = cont;
if (snd_BUG_ON(!frames)) {
- runtime->nowake = 0;
+ runtime->twake = 0;
snd_pcm_stream_unlock_irq(substream);
return -EINVAL;
}
@@ -2078,7 +2078,7 @@
xfer += frames;
}
_end_unlock:
- runtime->nowake = 0;
+ runtime->twake = 0;
if (xfer > 0 && err >= 0)
snd_pcm_update_state(substream, runtime);
snd_pcm_stream_unlock_irq(substream);
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 27284f6..56ec35e 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -919,6 +919,7 @@
runtime->status->state = state;
}
wake_up(&runtime->sleep);
+ wake_up(&runtime->tsleep);
}
static struct action_ops snd_pcm_action_stop = {
@@ -1004,6 +1005,7 @@
SNDRV_TIMER_EVENT_MPAUSE,
&runtime->trigger_tstamp);
wake_up(&runtime->sleep);
+ wake_up(&runtime->tsleep);
} else {
runtime->status->state = SNDRV_PCM_STATE_RUNNING;
if (substream->timer)
@@ -1061,6 +1063,7 @@
runtime->status->suspended_state = runtime->status->state;
runtime->status->state = SNDRV_PCM_STATE_SUSPENDED;
wake_up(&runtime->sleep);
+ wake_up(&runtime->tsleep);
}
static struct action_ops snd_pcm_action_suspend = {