Commit 6053a712 authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: aloop: Replace tasklet with work 

The tasklet is an old API that should be deprecated, usually can be
converted to another decent API.  In aloop driver, a tasklet is still
used for offloading the timer event task.  It can be achieved
gracefully with a work queued, too.

This patch replaces the tasklet usage in aloop driver with a simple
work.

Link: https://lore.kernel.org/r/20200903104131.21097-6-tiwai@suse.de


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 45e4d67f

sound/drivers/aloop.c

+11 −12
Original line number Diff line number Diff line
@@ -110,7 +110,7 @@ struct loopback_cable { 
	struct {

		int stream;

		struct snd_timer_id id;

		struct tasklet_struct event_tasklet;

		struct work_struct event_work;

		struct snd_timer_instance *instance;

	} snd_timer;

};
@@ -309,8 +309,8 @@ static int loopback_snd_timer_close_cable(struct loopback_pcm *dpcm) 
	 */

	snd_timer_close(cable->snd_timer.instance);



	/* wait till drain tasklet has finished if requested */

	tasklet_kill(&cable->snd_timer.event_tasklet);

	/* wait till drain work has finished if requested */

	cancel_work_sync(&cable->snd_timer.event_work);



	snd_timer_instance_free(cable->snd_timer.instance);

	memset(&cable->snd_timer, 0, sizeof(cable->snd_timer));
@@ -794,11 +794,11 @@ static void loopback_snd_timer_function(struct snd_timer_instance *timeri, 
					  resolution);

}



static void loopback_snd_timer_tasklet(unsigned long arg)

static void loopback_snd_timer_work(struct work_struct *work)

{

	struct snd_timer_instance *timeri = (struct snd_timer_instance *)arg;

	struct loopback_cable *cable = timeri->callback_data;

	struct loopback_cable *cable;



	cable = container_of(work, struct loopback_cable, snd_timer.event_work);

	loopback_snd_timer_period_elapsed(cable, SNDRV_TIMER_EVENT_MSTOP, 0);

}
@@ -828,9 +828,9 @@ static void loopback_snd_timer_event(struct snd_timer_instance *timeri, 
		 * state the streaming will be aborted by the usual timeout. It

		 * should not be aborted here because may be the timer sound

		 * card does only a recovery and the timer is back soon.

		 * This tasklet triggers loopback_snd_timer_tasklet()

		 * This work triggers loopback_snd_timer_work()

		 */

		tasklet_schedule(&cable->snd_timer.event_tasklet);

		schedule_work(&cable->snd_timer.event_work);

	}

}
@@ -1124,7 +1124,7 @@ static int loopback_snd_timer_open(struct loopback_pcm *dpcm) 
		err = -ENOMEM;

		goto exit;

	}

	/* The callback has to be called from another tasklet. If

	/* The callback has to be called from another work. If

	 * SNDRV_TIMER_IFLG_FAST is specified it will be called from the

	 * snd_pcm_period_elapsed() call of the selected sound card.

	 * snd_pcm_period_elapsed() helds snd_pcm_stream_lock_irqsave().
@@ -1137,9 +1137,8 @@ static int loopback_snd_timer_open(struct loopback_pcm *dpcm) 
	timeri->callback_data = (void *)cable;

	timeri->ccallback = loopback_snd_timer_event;



	/* initialise a tasklet used for draining */

	tasklet_init(&cable->snd_timer.event_tasklet,

		     loopback_snd_timer_tasklet, (unsigned long)timeri);

	/* initialise a work used for draining */

	INIT_WORK(&cable->snd_timer.event_work, loopback_snd_timer_work);



	/* The mutex loopback->cable_lock is kept locked.

	 * Therefore snd_timer_open() cannot be called a second time

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