Commit a02f7a17 authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: seq: ports: Use guard() for locking 



We can simplify the code gracefully with new guard() macro and co for
automatic cleanup of locks.

Only the code refactoring, and no functional changes.

Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20240227085306.9764-15-tiwai@suse.de
parent 6768bd10

sound/core/seq/seq_ports.c

+49 −65
Original line number Diff line number Diff line
@@ -48,17 +48,15 @@ struct snd_seq_client_port *snd_seq_port_use_ptr(struct snd_seq_client *client, 


	if (client == NULL)

		return NULL;

	read_lock(&client->ports_lock);

	guard(read_lock)(&client->ports_lock);

	list_for_each_entry(port, &client->ports_list_head, list) {

		if (port->addr.port == num) {

			if (port->closing)

				break; /* deleting now */

			snd_use_lock_use(&port->use_lock);

			read_unlock(&client->ports_lock);

			return port;

		}

	}

	read_unlock(&client->ports_lock);

	return NULL;		/* not found */

}
@@ -73,7 +71,7 @@ struct snd_seq_client_port *snd_seq_port_query_nearest(struct snd_seq_client *cl 


	num = pinfo->addr.port;

	found = NULL;

	read_lock(&client->ports_lock);

	guard(read_lock)(&client->ports_lock);

	list_for_each_entry(port, &client->ports_list_head, list) {

		if ((port->capability & SNDRV_SEQ_PORT_CAP_INACTIVE) &&

		    !check_inactive)
@@ -93,7 +91,6 @@ struct snd_seq_client_port *snd_seq_port_query_nearest(struct snd_seq_client *cl 
		else

			snd_use_lock_use(&found->use_lock);

	}

	read_unlock(&client->ports_lock);

	return found;

}
@@ -145,13 +142,12 @@ int snd_seq_create_port(struct snd_seq_client *client, int port, 
	snd_use_lock_use(&new_port->use_lock);



	num = max(port, 0);

	mutex_lock(&client->ports_mutex);

	write_lock_irq(&client->ports_lock);

	guard(mutex)(&client->ports_mutex);

	guard(write_lock_irq)(&client->ports_lock);

	list_for_each_entry(p, &client->ports_list_head, list) {

		if (p->addr.port == port) {

			kfree(new_port);

			num = -EBUSY;

			goto unlock;

			return -EBUSY;

		}

		if (p->addr.port > num)

			break;
@@ -164,9 +160,6 @@ int snd_seq_create_port(struct snd_seq_client *client, int port, 
	new_port->addr.port = num;	/* store the port number in the port */

	sprintf(new_port->name, "port-%d", num);

	*port_ret = new_port;

 unlock:

	write_unlock_irq(&client->ports_lock);

	mutex_unlock(&client->ports_mutex);



	return num;

}
@@ -281,8 +274,8 @@ int snd_seq_delete_port(struct snd_seq_client *client, int port) 
{

	struct snd_seq_client_port *found = NULL, *p;



	mutex_lock(&client->ports_mutex);

	write_lock_irq(&client->ports_lock);

	scoped_guard(mutex, &client->ports_mutex) {

		guard(write_lock_irq)(&client->ports_lock);

		list_for_each_entry(p, &client->ports_list_head, list) {

			if (p->addr.port == port) {

				/* ok found.  delete from the list at first */
@@ -292,8 +285,7 @@ int snd_seq_delete_port(struct snd_seq_client *client, int port) 
				break;

			}

		}

	write_unlock_irq(&client->ports_lock);

	mutex_unlock(&client->ports_mutex);

	}

	if (found)

		return port_delete(client, found);

	else
@@ -309,8 +301,8 @@ int snd_seq_delete_all_ports(struct snd_seq_client *client) 
	/* move the port list to deleted_list, and

	 * clear the port list in the client data.

	 */

	mutex_lock(&client->ports_mutex);

	write_lock_irq(&client->ports_lock);

	guard(mutex)(&client->ports_mutex);

	scoped_guard(write_lock_irq, &client->ports_lock) {

		if (!list_empty(&client->ports_list_head)) {

			list_add(&deleted_list, &client->ports_list_head);

			list_del_init(&client->ports_list_head);
@@ -318,7 +310,7 @@ int snd_seq_delete_all_ports(struct snd_seq_client *client) 
			INIT_LIST_HEAD(&deleted_list);

		}

		client->num_ports = 0;

	write_unlock_irq(&client->ports_lock);

	}



	/* remove each port in deleted_list */

	list_for_each_entry_safe(port, tmp, &deleted_list, list) {
@@ -326,7 +318,6 @@ int snd_seq_delete_all_ports(struct snd_seq_client *client) 
		snd_seq_system_client_ev_port_exit(port->addr.client, port->addr.port);

		port_delete(client, port);

	}

	mutex_unlock(&client->ports_mutex);

	return 0;

}
@@ -506,42 +497,37 @@ static int check_and_subscribe_port(struct snd_seq_client *client, 
	int err;



	grp = is_src ? &port->c_src : &port->c_dest;

	err = -EBUSY;

	down_write(&grp->list_mutex);

	guard(rwsem_write)(&grp->list_mutex);

	if (exclusive) {

		if (!list_empty(&grp->list_head))

			goto __error;

			return -EBUSY;

	} else {

		if (grp->exclusive)

			goto __error;

			return -EBUSY;

		/* check whether already exists */

		list_for_each(p, &grp->list_head) {

			s = get_subscriber(p, is_src);

			if (match_subs_info(&subs->info, &s->info))

				goto __error;

				return -EBUSY;

		}

	}



	err = subscribe_port(client, port, grp, &subs->info, ack);

	if (err < 0) {

		grp->exclusive = 0;

		goto __error;

		return err;

	}



	/* add to list */

	write_lock_irq(&grp->list_lock);

	guard(write_lock_irq)(&grp->list_lock);

	if (is_src)

		list_add_tail(&subs->src_list, &grp->list_head);

	else

		list_add_tail(&subs->dest_list, &grp->list_head);

	grp->exclusive = exclusive;

	atomic_inc(&subs->ref_count);

	write_unlock_irq(&grp->list_lock);

	err = 0;



 __error:

	up_write(&grp->list_mutex);

	return err;

	return 0;

}



/* called with grp->list_mutex held */
@@ -556,12 +542,12 @@ static void __delete_and_unsubscribe_port(struct snd_seq_client *client, 


	grp = is_src ? &port->c_src : &port->c_dest;

	list = is_src ? &subs->src_list : &subs->dest_list;

	write_lock_irq(&grp->list_lock);

	scoped_guard(write_lock_irq, &grp->list_lock) {

		empty = list_empty(list);

		if (!empty)

			list_del_init(list);

		grp->exclusive = 0;

	write_unlock_irq(&grp->list_lock);

	}



	if (!empty)

		unsubscribe_port(client, port, grp, &subs->info, ack);
@@ -575,9 +561,8 @@ static void delete_and_unsubscribe_port(struct snd_seq_client *client, 
	struct snd_seq_port_subs_info *grp;



	grp = is_src ? &port->c_src : &port->c_dest;

	down_write(&grp->list_mutex);

	guard(rwsem_write)(&grp->list_mutex);

	__delete_and_unsubscribe_port(client, port, subs, is_src, ack);

	up_write(&grp->list_mutex);

}



/* connect two ports */
@@ -639,7 +624,7 @@ int snd_seq_port_disconnect(struct snd_seq_client *connector, 
	/* always start from deleting the dest port for avoiding concurrent

	 * deletions

	 */

	down_write(&dest->list_mutex);

	scoped_guard(rwsem_write, &dest->list_mutex) {

		/* look for the connection */

		list_for_each_entry(subs, &dest->list_head, dest_list) {

			if (match_subs_info(info, &subs->info)) {
@@ -650,7 +635,7 @@ int snd_seq_port_disconnect(struct snd_seq_client *connector, 
				break;

			}

		}

	up_write(&dest->list_mutex);

	}

	if (err < 0)

		return err;
@@ -669,7 +654,7 @@ int snd_seq_port_get_subscription(struct snd_seq_port_subs_info *src_grp, 
	struct snd_seq_subscribers *s;

	int err = -ENOENT;



	down_read(&src_grp->list_mutex);

	guard(rwsem_read)(&src_grp->list_mutex);

	list_for_each_entry(s, &src_grp->list_head, src_list) {

		if (addr_match(dest_addr, &s->info.dest)) {

			*subs = s->info;
@@ -677,7 +662,6 @@ int snd_seq_port_get_subscription(struct snd_seq_port_subs_info *src_grp, 
			break;

		}

	}

	up_read(&src_grp->list_mutex);

	return err;

}