Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 10aa7cad authored by Anna-Maria Gleixner's avatar Anna-Maria Gleixner Committed by Takashi Iwai
Browse files

ALSA: pcm: Hide local_irq_disable/enable() and local_irqsave/restore() 



The snd_pcm_stream_lock_irq*() functions decouple disabling interrupts
from the actual locking process. This does not work as expected if the
locking primitives are replaced like on preempt-rt.

Provide one function for locking which uses correct locking primitives.

Signed-off-by: default avatarAnna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 9ea19e7e

sound/core/pcm_native.c

+57 −28
Original line number Diff line number Diff line
@@ -99,6 +99,57 @@ static inline void down_write_nonblock(struct rw_semaphore *lock) 
		cond_resched();

}



#define PCM_LOCK_DEFAULT	0

#define PCM_LOCK_IRQ	1

#define PCM_LOCK_IRQSAVE	2



static unsigned long __snd_pcm_stream_lock_mode(struct snd_pcm_substream *substream,

						unsigned int mode)

{

	unsigned long flags = 0;

	if (substream->pcm->nonatomic) {

		down_read_nested(&snd_pcm_link_rwsem, SINGLE_DEPTH_NESTING);

		mutex_lock(&substream->self_group.mutex);

	} else {

		switch (mode) {

		case PCM_LOCK_DEFAULT:

			read_lock(&snd_pcm_link_rwlock);

			break;

		case PCM_LOCK_IRQ:

			read_lock_irq(&snd_pcm_link_rwlock);

			break;

		case PCM_LOCK_IRQSAVE:

			read_lock_irqsave(&snd_pcm_link_rwlock, flags);

			break;

		}

		spin_lock(&substream->self_group.lock);

	}

	return flags;

}



static void __snd_pcm_stream_unlock_mode(struct snd_pcm_substream *substream,

					 unsigned int mode, unsigned long flags)

{

	if (substream->pcm->nonatomic) {

		mutex_unlock(&substream->self_group.mutex);

		up_read(&snd_pcm_link_rwsem);

	} else {

		spin_unlock(&substream->self_group.lock);



		switch (mode) {

		case PCM_LOCK_DEFAULT:

			read_unlock(&snd_pcm_link_rwlock);

			break;

		case PCM_LOCK_IRQ:

			read_unlock_irq(&snd_pcm_link_rwlock);

			break;

		case PCM_LOCK_IRQSAVE:

			read_unlock_irqrestore(&snd_pcm_link_rwlock, flags);

			break;

		}

	}

}



/**

 * snd_pcm_stream_lock - Lock the PCM stream

 * @substream: PCM substream
@@ -109,13 +160,7 @@ static inline void down_write_nonblock(struct rw_semaphore *lock) 
 */

void snd_pcm_stream_lock(struct snd_pcm_substream *substream)

{

	if (substream->pcm->nonatomic) {

		down_read_nested(&snd_pcm_link_rwsem, SINGLE_DEPTH_NESTING);

		mutex_lock(&substream->self_group.mutex);

	} else {

		read_lock(&snd_pcm_link_rwlock);

		spin_lock(&substream->self_group.lock);

	}

	__snd_pcm_stream_lock_mode(substream, PCM_LOCK_DEFAULT);

}

EXPORT_SYMBOL_GPL(snd_pcm_stream_lock);
@@ -127,13 +172,7 @@ EXPORT_SYMBOL_GPL(snd_pcm_stream_lock); 
 */

void snd_pcm_stream_unlock(struct snd_pcm_substream *substream)

{

	if (substream->pcm->nonatomic) {

		mutex_unlock(&substream->self_group.mutex);

		up_read(&snd_pcm_link_rwsem);

	} else {

		spin_unlock(&substream->self_group.lock);

		read_unlock(&snd_pcm_link_rwlock);

	}

	__snd_pcm_stream_unlock_mode(substream, PCM_LOCK_DEFAULT, 0);

}

EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock);
@@ -147,9 +186,7 @@ EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock); 
 */

void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream)

{

	if (!substream->pcm->nonatomic)

		local_irq_disable();

	snd_pcm_stream_lock(substream);

	__snd_pcm_stream_lock_mode(substream, PCM_LOCK_IRQ);

}

EXPORT_SYMBOL_GPL(snd_pcm_stream_lock_irq);
@@ -161,19 +198,13 @@ EXPORT_SYMBOL_GPL(snd_pcm_stream_lock_irq); 
 */

void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream)

{

	snd_pcm_stream_unlock(substream);

	if (!substream->pcm->nonatomic)

		local_irq_enable();

	__snd_pcm_stream_unlock_mode(substream, PCM_LOCK_IRQ, 0);

}

EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irq);



unsigned long _snd_pcm_stream_lock_irqsave(struct snd_pcm_substream *substream)

{

	unsigned long flags = 0;

	if (!substream->pcm->nonatomic)

		local_irq_save(flags);

	snd_pcm_stream_lock(substream);

	return flags;

	return __snd_pcm_stream_lock_mode(substream, PCM_LOCK_IRQSAVE);

}

EXPORT_SYMBOL_GPL(_snd_pcm_stream_lock_irqsave);
@@ -187,9 +218,7 @@ EXPORT_SYMBOL_GPL(_snd_pcm_stream_lock_irqsave); 
void snd_pcm_stream_unlock_irqrestore(struct snd_pcm_substream *substream,

				      unsigned long flags)

{

	snd_pcm_stream_unlock(substream);

	if (!substream->pcm->nonatomic)

		local_irq_restore(flags);

	__snd_pcm_stream_unlock_mode(substream, PCM_LOCK_IRQSAVE, flags);

}

EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irqrestore);