Commit 6bcd658f authored by Mikulas Patocka's avatar Mikulas Patocka Committed by Mike Snitzer
Browse files

dm kcopyd: avoid spin_lock_irqsave from process context 



The functions "pop", "push_head", "do_work" can only be called from
process context. Therefore, replace spin_lock_irq{save,restore} with
spin_{lock,unlock}_irq.

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent db2351eb

drivers/md/dm-kcopyd.c

+6 −9
Original line number Original line Diff line number Diff line
@@ -437,9 +437,8 @@ static struct kcopyd_job *pop(struct list_head *jobs, 
			      struct dm_kcopyd_client *kc)

			      struct dm_kcopyd_client *kc)

{

{

	struct kcopyd_job *job = NULL;

	struct kcopyd_job *job = NULL;

	unsigned long flags;





	spin_lock_irqsave(&kc->job_lock, flags);

	spin_lock_irq(&kc->job_lock);





	if (!list_empty(jobs)) {

	if (!list_empty(jobs)) {

		if (jobs == &kc->io_jobs)

		if (jobs == &kc->io_jobs)
@@ -449,7 +448,7 @@ static struct kcopyd_job *pop(struct list_head *jobs, 
			list_del(&job->list);

			list_del(&job->list);

		}

		}

	}

	}

	spin_unlock_irqrestore(&kc->job_lock, flags);

	spin_unlock_irq(&kc->job_lock);





	return job;

	return job;

}

}
@@ -467,12 +466,11 @@ static void push(struct list_head *jobs, struct kcopyd_job *job) 




static void push_head(struct list_head *jobs, struct kcopyd_job *job)

static void push_head(struct list_head *jobs, struct kcopyd_job *job)

{

{

	unsigned long flags;

	struct dm_kcopyd_client *kc = job->kc;

	struct dm_kcopyd_client *kc = job->kc;





	spin_lock_irqsave(&kc->job_lock, flags);

	spin_lock_irq(&kc->job_lock);

	list_add(&job->list, jobs);

	list_add(&job->list, jobs);

	spin_unlock_irqrestore(&kc->job_lock, flags);

	spin_unlock_irq(&kc->job_lock);

}

}





/*

/*
@@ -648,7 +646,6 @@ static void do_work(struct work_struct *work) 
	struct dm_kcopyd_client *kc = container_of(work,

	struct dm_kcopyd_client *kc = container_of(work,

					struct dm_kcopyd_client, kcopyd_work);

					struct dm_kcopyd_client, kcopyd_work);

	struct blk_plug plug;

	struct blk_plug plug;

	unsigned long flags;





	/*

	/*

	 * The order that these are called is *very* important.

	 * The order that these are called is *very* important.
@@ -657,9 +654,9 @@ static void do_work(struct work_struct *work) 
	 * list.  io jobs call wake when they complete and it all

	 * list.  io jobs call wake when they complete and it all

	 * starts again.

	 * starts again.

	 */

	 */

	spin_lock_irqsave(&kc->job_lock, flags);

	spin_lock_irq(&kc->job_lock);

	list_splice_tail_init(&kc->callback_jobs, &kc->complete_jobs);

	list_splice_tail_init(&kc->callback_jobs, &kc->complete_jobs);

	spin_unlock_irqrestore(&kc->job_lock, flags);

	spin_unlock_irq(&kc->job_lock);





	blk_start_plug(&plug);

	blk_start_plug(&plug);

	process_jobs(&kc->complete_jobs, kc, run_complete_job);

	process_jobs(&kc->complete_jobs, kc, run_complete_job);