From: Takashi Iwai <tiwai@suse.de>
To: alsa-devel@alsa-project.org
Subject: [alsa-devel] [PATCH 1/3] ALSA: timer: Unify master/slave linking code
Date: Thu, 7 Nov 2019 20:20:06 +0100 [thread overview]
Message-ID: <20191107192008.32331-2-tiwai@suse.de> (raw)
In-Reply-To: <20191107192008.32331-1-tiwai@suse.de>
The code in both snd_timer_check_master() and snd_timer_check_slave()
are almost identical, both check whether the master/slave link and
does linkage. Factor out the common code and call it from both
functions for readability.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
sound/core/timer.c | 66 +++++++++++++++++++++++++++---------------------------
1 file changed, 33 insertions(+), 33 deletions(-)
diff --git a/sound/core/timer.c b/sound/core/timer.c
index 013f0e69ff0f..21c2d25e4074 100644
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -163,6 +163,28 @@ static void snd_timer_request(struct snd_timer_id *tid)
#endif
+/* move the slave if it belongs to the master; return 1 if match */
+static int check_matching_master_slave(struct snd_timer_instance *master,
+ struct snd_timer_instance *slave)
+{
+ if (slave->slave_class != master->slave_class ||
+ slave->slave_id != master->slave_id)
+ return 0;
+ if (master->timer->num_instances >= master->timer->max_instances)
+ return -EBUSY;
+ list_move_tail(&slave->open_list, &master->slave_list_head);
+ master->timer->num_instances++;
+ spin_lock_irq(&slave_active_lock);
+ spin_lock(&master->timer->lock);
+ slave->master = master;
+ slave->timer = master->timer;
+ if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
+ list_add_tail(&slave->active_list, &master->slave_active_head);
+ spin_unlock(&master->timer->lock);
+ spin_unlock_irq(&slave_active_lock);
+ return 1;
+}
+
/*
* look for a master instance matching with the slave id of the given slave.
* when found, relink the open_link of the slave.
@@ -173,27 +195,18 @@ static int snd_timer_check_slave(struct snd_timer_instance *slave)
{
struct snd_timer *timer;
struct snd_timer_instance *master;
+ int err = 0;
/* FIXME: it's really dumb to look up all entries.. */
list_for_each_entry(timer, &snd_timer_list, device_list) {
list_for_each_entry(master, &timer->open_list_head, open_list) {
- if (slave->slave_class == master->slave_class &&
- slave->slave_id == master->slave_id) {
- if (master->timer->num_instances >=
- master->timer->max_instances)
- return -EBUSY;
- list_move_tail(&slave->open_list,
- &master->slave_list_head);
- master->timer->num_instances++;
- spin_lock_irq(&slave_active_lock);
- slave->master = master;
- slave->timer = master->timer;
- spin_unlock_irq(&slave_active_lock);
- return 0;
- }
+ err = check_matching_master_slave(master, slave);
+ if (err != 0) /* match found or error */
+ goto out;
}
}
- return 0;
+ out:
+ return err < 0 ? err : 0;
}
/*
@@ -205,28 +218,15 @@ static int snd_timer_check_slave(struct snd_timer_instance *slave)
static int snd_timer_check_master(struct snd_timer_instance *master)
{
struct snd_timer_instance *slave, *tmp;
+ int err = 0;
/* check all pending slaves */
list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
- if (slave->slave_class == master->slave_class &&
- slave->slave_id == master->slave_id) {
- if (master->timer->num_instances >=
- master->timer->max_instances)
- return -EBUSY;
- list_move_tail(&slave->open_list, &master->slave_list_head);
- master->timer->num_instances++;
- spin_lock_irq(&slave_active_lock);
- spin_lock(&master->timer->lock);
- slave->master = master;
- slave->timer = master->timer;
- if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
- list_add_tail(&slave->active_list,
- &master->slave_active_head);
- spin_unlock(&master->timer->lock);
- spin_unlock_irq(&slave_active_lock);
- }
+ err = check_matching_master_slave(master, slave);
+ if (err < 0)
+ break;
}
- return 0;
+ return err < 0 ? err : 0;
}
static int snd_timer_close_locked(struct snd_timer_instance *timeri,
--
2.16.4
_______________________________________________
Alsa-devel mailing list
Alsa-devel@alsa-project.org
https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
next prev parent reply other threads:[~2019-11-07 19:22 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-07 19:20 [alsa-devel] [PATCH 0/3] ALSA: timer: A few more fixes Takashi Iwai
2019-11-07 19:20 ` Takashi Iwai [this message]
2019-11-07 19:20 ` [alsa-devel] [PATCH 2/3] ALSA: timer: Make snd_timer_close() returning void Takashi Iwai
2019-11-07 19:20 ` [alsa-devel] [PATCH 3/3] ALSA: timer: Fix possible race at assigning a timer instance Takashi Iwai
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20191107192008.32331-2-tiwai@suse.de \
--to=tiwai@suse.de \
--cc=alsa-devel@alsa-project.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).