2 files changed, 53 insertions, 41 deletions

diff --git a/sound/core/control.c b/sound/core/control.c
index 9aa15bfc7936..649d3217590e 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -348,6 +348,40 @@ static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
 	return 0;
 }
 
+/* add a new kcontrol object; call with card->controls_rwsem locked */
+static int __snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
+{
+	struct snd_ctl_elem_id id;
+	unsigned int idx;
+	unsigned int count;
+
+	id = kcontrol->id;
+	if (id.index > UINT_MAX - kcontrol->count)
+		return -EINVAL;
+
+	if (snd_ctl_find_id(card, &id)) {
+		dev_err(card->dev,
+			"control %i:%i:%i:%s:%i is already present\n",
+			id.iface, id.device, id.subdevice, id.name, id.index);
+		return -EBUSY;
+	}
+
+	if (snd_ctl_find_hole(card, kcontrol->count) < 0)
+		return -ENOMEM;
+
+	list_add_tail(&kcontrol->list, &card->controls);
+	card->controls_count += kcontrol->count;
+	kcontrol->id.numid = card->last_numid + 1;
+	card->last_numid += kcontrol->count;
+
+	id = kcontrol->id;
+	count = kcontrol->count;
+	for (idx = 0; idx < count; idx++, id.index++, id.numid++)
+		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
+
+	return 0;
+}
+
 /**
  * snd_ctl_add - add the control instance to the card
  * @card: the card instance
@@ -364,45 +398,18 @@ static int snd_ctl_find_hole(struct snd_card *card, unsigned int count)
  */
 int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
 {
-	struct snd_ctl_elem_id id;
-	unsigned int idx;
-	unsigned int count;
 	int err = -EINVAL;
 
 	if (! kcontrol)
 		return err;
 	if (snd_BUG_ON(!card || !kcontrol->info))
 		goto error;
-	id = kcontrol->id;
-	if (id.index > UINT_MAX - kcontrol->count)
-		goto error;
 
 	down_write(&card->controls_rwsem);
-	if (snd_ctl_find_id(card, &id)) {
-		up_write(&card->controls_rwsem);
-		dev_err(card->dev, "control %i:%i:%i:%s:%i is already present\n",
-					id.iface,
-					id.device,
-					id.subdevice,
-					id.name,
-					id.index);
-		err = -EBUSY;
-		goto error;
-	}
-	if (snd_ctl_find_hole(card, kcontrol->count) < 0) {
-		up_write(&card->controls_rwsem);
-		err = -ENOMEM;
-		goto error;
-	}
-	list_add_tail(&kcontrol->list, &card->controls);
-	card->controls_count += kcontrol->count;
-	kcontrol->id.numid = card->last_numid + 1;
-	card->last_numid += kcontrol->count;
-	id = kcontrol->id;
-	count = kcontrol->count;
+	err = __snd_ctl_add(card, kcontrol);
 	up_write(&card->controls_rwsem);
-	for (idx = 0; idx < count; idx++, id.index++, id.numid++)
-		snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_ADD, &id);
+	if (err < 0)
+		goto error;
 	return 0;
 
  error:
@@ -1361,9 +1368,12 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file,
 		kctl->tlv.c = snd_ctl_elem_user_tlv;
 
 	/* This function manage to free the instance on failure. */
-	err = snd_ctl_add(card, kctl);
-	if (err < 0)
-		return err;
+	down_write(&card->controls_rwsem);
+	err = __snd_ctl_add(card, kctl);
+	if (err < 0) {
+		snd_ctl_free_one(kctl);
+		goto unlock;
+	}
 	offset = snd_ctl_get_ioff(kctl, &info->id);
 	snd_ctl_build_ioff(&info->id, kctl, offset);
 	/*
@@ -1374,10 +1384,10 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file,
 	 * which locks the element.
 	 */
 
-	down_write(&card->controls_rwsem);
 	card->user_ctl_count++;
-	up_write(&card->controls_rwsem);
 
+ unlock:
+	up_write(&card->controls_rwsem);
 	return 0;
 }
 
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 66c90f486af9..818dff1de545 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -36,6 +36,7 @@
 #include <sound/timer.h>
 #include <sound/minors.h>
 #include <linux/uio.h>
+#include <linux/delay.h>
 
 #include "pcm_local.h"
 
@@ -91,12 +92,12 @@ static DECLARE_RWSEM(snd_pcm_link_rwsem);
  * and this may lead to a deadlock when the code path takes read sem
  * twice (e.g. one in snd_pcm_action_nonatomic() and another in
  * snd_pcm_stream_lock()).  As a (suboptimal) workaround, let writer to
- * spin until it gets the lock.
+ * sleep until all the readers are completed without blocking by writer.
  */
-static inline void down_write_nonblock(struct rw_semaphore *lock)
+static inline void down_write_nonfifo(struct rw_semaphore *lock)
 {
 	while (!down_write_trylock(lock))
-		cond_resched();
+		msleep(1);
 }
 
 #define PCM_LOCK_DEFAULT	0
@@ -1967,7 +1968,7 @@ static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
 		res = -ENOMEM;
 		goto _nolock;
 	}
-	down_write_nonblock(&snd_pcm_link_rwsem);
+	down_write_nonfifo(&snd_pcm_link_rwsem);
 	write_lock_irq(&snd_pcm_link_rwlock);
 	if (substream->runtime->status->state == SNDRV_PCM_STATE_OPEN ||
 	    substream->runtime->status->state != substream1->runtime->status->state ||
@@ -2014,7 +2015,7 @@ static int snd_pcm_unlink(struct snd_pcm_substream *substream)
 	struct snd_pcm_substream *s;
 	int res = 0;
 
-	down_write_nonblock(&snd_pcm_link_rwsem);
+	down_write_nonfifo(&snd_pcm_link_rwsem);
 	write_lock_irq(&snd_pcm_link_rwlock);
 	if (!snd_pcm_stream_linked(substream)) {
 		res = -EALREADY;
@@ -2369,7 +2370,8 @@ int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream)
 
 static void pcm_release_private(struct snd_pcm_substream *substream)
 {
-	snd_pcm_unlink(substream);
+	if (snd_pcm_stream_linked(substream))
+		snd_pcm_unlink(substream);
 }
 
 void snd_pcm_release_substream(struct snd_pcm_substream *substream)