summaryrefslogtreecommitdiffstats
path: root/sound/core/pcm_native.c
diff options
context:
space:
mode:
authorTakashi Iwai <tiwai@suse.de>2019-01-13 09:40:21 +0100
committerTakashi Iwai <tiwai@suse.de>2019-01-21 16:39:54 +0100
commita41c4cb913b53bf74f1ec66a4b96057626c87009 (patch)
treea063f1c6b8276a20ac40e407e77454ae303d1860 /sound/core/pcm_native.c
parent73365cb10b280e539bad14e129e0d8434418bb79 (diff)
downloadlinux-a41c4cb913b53bf74f1ec66a4b96057626c87009.tar.bz2
ALSA: pcm: Make PCM linked list consistent while re-grouping
Make a common helper to re-assign the PCM link using list_move() instead of open code with manual list_del() and list_add_tail(). This assures the consistency and we can get rid of snd_pcm_group.count field -- its purpose is only to check whether the list is singular, and we can know it by list_is_singular() call now. Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/core/pcm_native.c')
-rw-r--r--sound/core/pcm_native.c34
1 files changed, 20 insertions, 14 deletions
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 9e4e289e5703..1a56bb1ad780 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -1131,6 +1131,13 @@ static int snd_pcm_action_single(const struct action_ops *ops,
return res;
}
+static void snd_pcm_group_assign(struct snd_pcm_substream *substream,
+ struct snd_pcm_group *new_group)
+{
+ substream->group = new_group;
+ list_move(&substream->link_list, &new_group->substreams);
+}
+
/*
* Note: call with stream lock
*/
@@ -1995,14 +2002,10 @@ static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
goto _end;
}
if (!snd_pcm_stream_linked(substream)) {
- substream->group = group;
+ snd_pcm_group_assign(substream, group);
group = NULL;
- list_add_tail(&substream->link_list, &substream->group->substreams);
- substream->group->count = 1;
}
- list_add_tail(&substream1->link_list, &substream->group->substreams);
- substream->group->count++;
- substream1->group = substream->group;
+ snd_pcm_group_assign(substream1, substream->group);
_end:
write_unlock_irq(&snd_pcm_link_rwlock);
up_write(&snd_pcm_link_rwsem);
@@ -2015,14 +2018,13 @@ static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
static void relink_to_local(struct snd_pcm_substream *substream)
{
- substream->group = &substream->self_group;
- INIT_LIST_HEAD(&substream->self_group.substreams);
- list_add_tail(&substream->link_list, &substream->self_group.substreams);
+ snd_pcm_group_assign(substream, &substream->self_group);
}
static int snd_pcm_unlink(struct snd_pcm_substream *substream)
{
struct snd_pcm_substream *s;
+ struct snd_pcm_group *group;
int res = 0;
down_write_nonfifo(&snd_pcm_link_rwsem);
@@ -2031,16 +2033,20 @@ static int snd_pcm_unlink(struct snd_pcm_substream *substream)
res = -EALREADY;
goto _end;
}
- list_del(&substream->link_list);
- substream->group->count--;
- if (substream->group->count == 1) { /* detach the last stream, too */
+
+ group = substream->group;
+
+ relink_to_local(substream);
+
+ /* detach the last stream, too */
+ if (list_is_singular(&group->substreams)) {
snd_pcm_group_for_each_entry(s, substream) {
relink_to_local(s);
break;
}
- kfree(substream->group);
+ kfree(group);
}
- relink_to_local(substream);
+
_end:
write_unlock_irq(&snd_pcm_link_rwlock);
up_write(&snd_pcm_link_rwsem);