Commit db2351eb authored by Mikulas Patocka's avatar Mikulas Patocka Committed by Mike Snitzer
Browse files

dm kcopyd: avoid useless atomic operations 



The functions set_bit and clear_bit are atomic. We don't need
atomicity when making flags for dm-kcopyd. So, change them to direct
manipulation of the flags.

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
parent 6b06dd5a

drivers/md/dm-kcopyd.c

+10 −10
Original line number Original line Diff line number Diff line
@@ -341,7 +341,7 @@ static void client_free_pages(struct dm_kcopyd_client *kc) 
struct kcopyd_job {

struct kcopyd_job {

	struct dm_kcopyd_client *kc;

	struct dm_kcopyd_client *kc;

	struct list_head list;

	struct list_head list;

	unsigned long flags;

	unsigned flags;





	/*

	/*

	 * Error state of the job.

	 * Error state of the job.
@@ -418,7 +418,7 @@ static struct kcopyd_job *pop_io_job(struct list_head *jobs, 
	 * constraint and sequential writes that are at the right position.

	 * constraint and sequential writes that are at the right position.

	 */

	 */

	list_for_each_entry(job, jobs, list) {

	list_for_each_entry(job, jobs, list) {

		if (job->rw == READ || !test_bit(DM_KCOPYD_WRITE_SEQ, &job->flags)) {

		if (job->rw == READ || !(job->flags & BIT(DM_KCOPYD_WRITE_SEQ))) {

			list_del(&job->list);

			list_del(&job->list);

			return job;

			return job;

		}

		}
@@ -525,7 +525,7 @@ static void complete_io(unsigned long error, void *context) 
		else

		else

			job->read_err = 1;

			job->read_err = 1;





		if (!test_bit(DM_KCOPYD_IGNORE_ERROR, &job->flags)) {

		if (!(job->flags & BIT(DM_KCOPYD_IGNORE_ERROR))) {

			push(&kc->complete_jobs, job);

			push(&kc->complete_jobs, job);

			wake(kc);

			wake(kc);

			return;

			return;
@@ -565,7 +565,7 @@ static int run_io_job(struct kcopyd_job *job) 
	 * If we need to write sequentially and some reads or writes failed,

	 * If we need to write sequentially and some reads or writes failed,

	 * no point in continuing.

	 * no point in continuing.

	 */

	 */

	if (test_bit(DM_KCOPYD_WRITE_SEQ, &job->flags) &&

	if (job->flags & BIT(DM_KCOPYD_WRITE_SEQ) &&

	    job->master_job->write_err) {

	    job->master_job->write_err) {

		job->write_err = job->master_job->write_err;

		job->write_err = job->master_job->write_err;

		return -EIO;

		return -EIO;
@@ -709,7 +709,7 @@ static void segment_complete(int read_err, unsigned long write_err, 
	 * Only dispatch more work if there hasn't been an error.

	 * Only dispatch more work if there hasn't been an error.

	 */

	 */

	if ((!job->read_err && !job->write_err) ||

	if ((!job->read_err && !job->write_err) ||

	    test_bit(DM_KCOPYD_IGNORE_ERROR, &job->flags)) {

	    job->flags & BIT(DM_KCOPYD_IGNORE_ERROR)) {

		/* get the next chunk of work */

		/* get the next chunk of work */

		progress = job->progress;

		progress = job->progress;

		count = job->source.count - progress;

		count = job->source.count - progress;
@@ -801,10 +801,10 @@ void dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from, 
	 * we need to write sequentially. If one of the destination is a

	 * we need to write sequentially. If one of the destination is a

	 * host-aware device, then leave it to the caller to choose what to do.

	 * host-aware device, then leave it to the caller to choose what to do.

	 */

	 */

	if (!test_bit(DM_KCOPYD_WRITE_SEQ, &job->flags)) {

	if (!(job->flags & BIT(DM_KCOPYD_WRITE_SEQ))) {

		for (i = 0; i < job->num_dests; i++) {

		for (i = 0; i < job->num_dests; i++) {

			if (bdev_zoned_model(dests[i].bdev) == BLK_ZONED_HM) {

			if (bdev_zoned_model(dests[i].bdev) == BLK_ZONED_HM) {

				set_bit(DM_KCOPYD_WRITE_SEQ, &job->flags);

				job->flags |= BIT(DM_KCOPYD_WRITE_SEQ);

				break;

				break;

			}

			}

		}

		}
@@ -813,9 +813,9 @@ void dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from, 
	/*

	/*

	 * If we need to write sequentially, errors cannot be ignored.

	 * If we need to write sequentially, errors cannot be ignored.

	 */

	 */

	if (test_bit(DM_KCOPYD_WRITE_SEQ, &job->flags) &&

	if (job->flags & BIT(DM_KCOPYD_WRITE_SEQ) &&

	    test_bit(DM_KCOPYD_IGNORE_ERROR, &job->flags))

	    job->flags & BIT(DM_KCOPYD_IGNORE_ERROR))

		clear_bit(DM_KCOPYD_IGNORE_ERROR, &job->flags);

		job->flags &= ~BIT(DM_KCOPYD_IGNORE_ERROR);





	if (from) {

	if (from) {

		job->source = *from;

		job->source = *from;

drivers/md/dm-raid1.c

+1 −1
Original line number Original line Diff line number Diff line
@@ -364,7 +364,7 @@ static void recover(struct mirror_set *ms, struct dm_region *reg) 




	/* hand to kcopyd */

	/* hand to kcopyd */

	if (!errors_handled(ms))

	if (!errors_handled(ms))

		set_bit(DM_KCOPYD_IGNORE_ERROR, &flags);

		flags |= BIT(DM_KCOPYD_IGNORE_ERROR);





	dm_kcopyd_copy(ms->kcopyd_client, &from, ms->nr_mirrors - 1, to,

	dm_kcopyd_copy(ms->kcopyd_client, &from, ms->nr_mirrors - 1, to,

		       flags, recovery_complete, reg);

		       flags, recovery_complete, reg);

drivers/md/dm-zoned-reclaim.c

+1 −1
Original line number Original line Diff line number Diff line
@@ -134,7 +134,7 @@ static int dmz_reclaim_copy(struct dmz_reclaim *zrc, 
	dst_zone_block = dmz_start_block(zmd, dst_zone);

	dst_zone_block = dmz_start_block(zmd, dst_zone);





	if (dmz_is_seq(dst_zone))

	if (dmz_is_seq(dst_zone))

		set_bit(DM_KCOPYD_WRITE_SEQ, &flags);

		flags |= BIT(DM_KCOPYD_WRITE_SEQ);





	while (block < end_block) {

	while (block < end_block) {

		if (src_zone->dev->flags & DMZ_BDEV_DYING)

		if (src_zone->dev->flags & DMZ_BDEV_DYING)