Commit 8b21ac87 authored by Benjamin Marzinski's avatar Benjamin Marzinski Committed by Mike Snitzer
Browse files

dm-delay: remove timer_lock 



Instead of manually checking the timer details in queue_timeout(), call
timer_reduce() to start the timer or reduce the expiration time. This
avoids needing a lock.

Signed-off-by: default avatarBenjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@kernel.org>
parent c542ee14

drivers/md/dm-delay.c

+1 −9
Original line number Diff line number Diff line
@@ -28,7 +28,6 @@ struct delay_class { 


struct delay_c {

	struct timer_list delay_timer;

	struct mutex timer_lock;

	struct mutex process_bios_lock; /* hold while removing bios to be processed from list */

	spinlock_t delayed_bios_lock; /* hold on all accesses to delayed_bios list */

	struct workqueue_struct *kdelayd_wq;
@@ -60,12 +59,7 @@ static void handle_delayed_timer(struct timer_list *t) 


static void queue_timeout(struct delay_c *dc, unsigned long expires)

{

	mutex_lock(&dc->timer_lock);



	if (!timer_pending(&dc->delay_timer) || expires < dc->delay_timer.expires)

		mod_timer(&dc->delay_timer, expires);



	mutex_unlock(&dc->timer_lock);

	timer_reduce(&dc->delay_timer, expires);

}



static inline bool delay_is_fast(struct delay_c *dc)
@@ -176,7 +170,6 @@ static void delay_dtr(struct dm_target *ti) 
		kthread_stop(dc->worker);



	mutex_destroy(&dc->process_bios_lock);

	mutex_destroy(&dc->timer_lock);



	kfree(dc);

}
@@ -234,7 +227,6 @@ static int delay_ctr(struct dm_target *ti, unsigned int argc, char **argv) 


	ti->private = dc;

	INIT_LIST_HEAD(&dc->delayed_bios);

	mutex_init(&dc->timer_lock);

	mutex_init(&dc->process_bios_lock);

	spin_lock_init(&dc->delayed_bios_lock);

	dc->may_delay = true;