kernel/linux.git/include/sound/control.h, branch v6.19.11

Merge branch 'topic/control-lookup-rwlock' into for-next

2024-08-09T12:25:24+00:00

Pull control lookup optimization changes. Signed-off-by: Takashi Iwai

ASoC: Drop snd_soc_*_get_kcontrol_locked()

2024-08-09T12:24:55+00:00

The recent cleanup in ALSA control core made no difference between snd_ctl_find_id_mixer() and snd_ctl_find_id_mixer_locked(), and the latter is to be dropped. The only user of the left API was ASoC, and that's snd_soc_card_get_kcontrol_locked() and snd_soc_component_get_kcontrol_locked(). This patch drops those functions and rewrites those users to call the variant without locked instead. The test of the API became superfluous, hence dropped as well. As all callers of snd_ctl_find_id_mixer_locked() are gone, snd_ctl_find_id_mixer_locked() is finally dropped, too. Reviewed-by: Mark Brown Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20240809104234.8488-4-tiwai@suse.de

ALSA: control: Optimize locking for look-up

2024-08-09T12:24:55+00:00

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 Link: https://patch.msgid.link/20240809104234.8488-3-tiwai@suse.de

ALSA: control: Annotate snd_kcontrol with __counted_by()

2024-07-30T05:45:37+00:00

struct snd_kcontrol contains a flex array of snd_kcontrol_volatile objects at its end, and the array size is stored in count field. This can be annotated gracefully with __counted_by() for catching possible array overflows. One additional change is the order of the count field initialization; The assignment of the count field is moved before assignment of vd[] elements for avoiding false-positive warnings from compilers. Link: https://patch.msgid.link/20240726152840.8629-1-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: control: Introduce snd_ctl_find_id_mixer_locked()

2024-04-02T14:54:47+00:00

Adds wrapper function snd_ctl_find_id_mixer_locked(). This is identical to snd_ctl_find_id_mixer() except that it can be called from code that is already holding controls_rwsem. Signed-off-by: Richard Fitzgerald Reviewed-by: Takashi Iwai Link: https://msgid.link/r/20240401100210.61277-2-rf@opensource.cirrus.com Signed-off-by: Mark Brown

ALSA: vmaster: Add snd_ctl_add_followers() helper

2023-07-21T07:37:47+00:00

Add a new helper to add multiple vmaster followers in a shot. The same function was open-coded in various places, and this helper replaces them. Link: https://lore.kernel.org/r/20230721071643.3631-2-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: control: Introduce snd_ctl_find_id_mixer()

2023-07-21T07:10:38+00:00

A commonly seen pattern is to run snd_ctl_find_id() for a mixer control element with a given string. Let's provide a standard helper for achieving that for simplifying the code. Link: https://lore.kernel.org/r/20230720082108.31346-2-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: control: Introduce unlocked version for snd_ctl_find_*() helpers

2023-07-20T08:03:00+00:00

For reducing the unnecessary use of controls_rwsem in the drivers, this patch adds a new variant for snd_ctl_find_*() helpers: snd_ctl_find_id_locked() and snd_ctl_find_numid_locked() look for a kctl element inside the card->controls_rwsem -- that is, doing the very same as what snd_ctl_find_id() and snd_ctl_find_numid() did until now. snd_ctl_find_id() and snd_ctl_find_numid() remain same, i.e. still unlocked version, but they will be switched to locked version once after all callers are replaced. The patch also replaces the calls of snd_ctl_find_id() and snd_ctl_find_numid() in a few places; all of those are places where we know that the functions are called properly with controls_rwsem held. All others are without rwsem (although they should have been). After this patch, we'll turn on the locking in snd_ctl_find_id() and snd_ctl_find_numid() to be more race-free. Link: https://lore.kernel.org/r/20230718141304.1032-10-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: control: Make snd_ctl_find_id() argument const

2023-07-20T08:02:59+00:00

The id object passed to snd_ctl_find_id() is only read, and we can mark it with const gracefully. Link: https://lore.kernel.org/r/20230718141304.1032-9-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: control: add snd_ctl_rename()

2022-10-21T06:17:08+00:00

Add a snd_ctl_rename() function that takes care of updating the control hash entries for callers that already have the relevant struct snd_kcontrol at hand and hold the control write lock (or simply haven't registered the card yet). Fixes: c27e1efb61c5 ("ALSA: control: Use xarray for faster lookups") Cc: stable@vger.kernel.org Signed-off-by: Maciej S. Szmigiero Link: https://lore.kernel.org/r/4170b71117ea81357a4f7eb8410f7cde20836c70.1666296963.git.maciej.szmigiero@oracle.com Signed-off-by: Takashi Iwai