diff options
| author | Takashi Iwai <tiwai@suse.de> | 2024-08-09 12:42:30 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2024-08-09 14:24:55 +0200 |
| commit | 38ea4c3dc306edf6f4e483e8ad9cb8d33943afde (patch) | |
| tree | 241b50a1da29ca1bafcd5115ca43d3567aec3f38 /sound/core/oss | |
| parent | f428cc9eac6e29d57579be4978ba210c344322ea (diff) | |
ALSA: control: Optimize locking for look-up
For a fast look-up of a control element via either numid or name
matching (enabled via CONFIG_SND_CTL_FAST_LOOKUP), a locking isn't
needed at all thanks to Xarray. OTOH, the locking is still needed for
a slow linked-list traversal, and that's rather a rare case.
In this patch, we reduce the use of locking at snd_ctl_find_*() API
functions, and switch from controls_rwsem to controls_rwlock for
avoiding unnecessary lock inversions. This also resulted in a nice
cleanup, as *_unlocked() version of snd_ctl_find_*() APIs can be
dropped.
snd_ctl_find_id_mixer_unlocked() is still left just as an alias of
snd_ctl_find_id_mixer(), since soc-card.c has a wrapper and there are
several users. Once after converting there, we can remove it later.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20240809104234.8488-3-tiwai@suse.de
Diffstat (limited to 'sound/core/oss')
| -rw-r--r-- | sound/core/oss/mixer_oss.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/sound/core/oss/mixer_oss.c b/sound/core/oss/mixer_oss.c index 6a0508093ea6..33bf9a220ada 100644 --- a/sound/core/oss/mixer_oss.c +++ b/sound/core/oss/mixer_oss.c @@ -510,7 +510,7 @@ static struct snd_kcontrol *snd_mixer_oss_test_id(struct snd_mixer_oss *mixer, c id.iface = SNDRV_CTL_ELEM_IFACE_MIXER; strscpy(id.name, name, sizeof(id.name)); id.index = index; - return snd_ctl_find_id_locked(card, &id); + return snd_ctl_find_id(card, &id); } static void snd_mixer_oss_get_volume1_vol(struct snd_mixer_oss_file *fmixer, @@ -526,7 +526,7 @@ static void snd_mixer_oss_get_volume1_vol(struct snd_mixer_oss_file *fmixer, if (numid == ID_UNKNOWN) return; guard(rwsem_read)(&card->controls_rwsem); - kctl = snd_ctl_find_numid_locked(card, numid); + kctl = snd_ctl_find_numid(card, numid); if (!kctl) return; uinfo = kzalloc(sizeof(*uinfo), GFP_KERNEL); @@ -559,7 +559,7 @@ static void snd_mixer_oss_get_volume1_sw(struct snd_mixer_oss_file *fmixer, if (numid == ID_UNKNOWN) return; guard(rwsem_read)(&card->controls_rwsem); - kctl = snd_ctl_find_numid_locked(card, numid); + kctl = snd_ctl_find_numid(card, numid); if (!kctl) return; uinfo = kzalloc(sizeof(*uinfo), GFP_KERNEL); @@ -619,7 +619,7 @@ static void snd_mixer_oss_put_volume1_vol(struct snd_mixer_oss_file *fmixer, if (numid == ID_UNKNOWN) return; guard(rwsem_read)(&card->controls_rwsem); - kctl = snd_ctl_find_numid_locked(card, numid); + kctl = snd_ctl_find_numid(card, numid); if (!kctl) return; uinfo = kzalloc(sizeof(*uinfo), GFP_KERNEL); @@ -656,7 +656,7 @@ static void snd_mixer_oss_put_volume1_sw(struct snd_mixer_oss_file *fmixer, if (numid == ID_UNKNOWN) return; guard(rwsem_read)(&card->controls_rwsem); - kctl = snd_ctl_find_numid_locked(card, numid); + kctl = snd_ctl_find_numid(card, numid); if (!kctl) return; uinfo = kzalloc(sizeof(*uinfo), GFP_KERNEL); |