From db2351eb22e42c5e29ce0caa967a10bb34efabb5 Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <mpatocka@redhat.com>
Date: Wed, 26 May 2021 10:16:01 -0400
Subject: [PATCH] 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: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
---
drivers/md/dm-kcopyd.c | 20 ++++++++++----------
drivers/md/dm-raid1.c | 2 +-
drivers/md/dm-zoned-reclaim.c | 2 +-
3 files changed, 12 insertions(+), 12 deletions(-)
diff --git a/drivers/md/dm-kcopyd.c b/drivers/md/dm-kcopyd.c
index 1bbe4a34ef4c..d85a65a4274e 100644
--- a/drivers/md/dm-kcopyd.c
+++ b/drivers/md/dm-kcopyd.c
@@ -341,7 +341,7 @@ static void client_free_pages(struct dm_kcopyd_client *kc)
struct kcopyd_job {
struct dm_kcopyd_client *kc;
struct list_head list;
- unsigned long flags;
+ unsigned flags;
/*
* 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.
*/
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);
return job;
}
@@ -525,7 +525,7 @@ static void complete_io(unsigned long error, void *context)
else
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);
wake(kc);
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,
* 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->write_err = job->master_job->write_err;
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.
*/
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 */
progress = job->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
* 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++) {
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;
}
}
@@ -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 (test_bit(DM_KCOPYD_WRITE_SEQ, &job->flags) &&
- test_bit(DM_KCOPYD_IGNORE_ERROR, &job->flags))
- clear_bit(DM_KCOPYD_IGNORE_ERROR, &job->flags);
+ if (job->flags & BIT(DM_KCOPYD_WRITE_SEQ) &&
+ job->flags & BIT(DM_KCOPYD_IGNORE_ERROR))
+ job->flags &= ~BIT(DM_KCOPYD_IGNORE_ERROR);
if (from) {
job->source = *from;
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c
index b0a82f29a2e4..ebb4810cc3b4 100644
--- a/drivers/md/dm-raid1.c
+++ b/drivers/md/dm-raid1.c
@@ -364,7 +364,7 @@ static void recover(struct mirror_set *ms, struct dm_region *reg)
/* hand to kcopyd */
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,
flags, recovery_complete, reg);
diff --git a/drivers/md/dm-zoned-reclaim.c b/drivers/md/dm-zoned-reclaim.c
index 9c0ecc9568a4..d58db9a27e6c 100644
--- a/drivers/md/dm-zoned-reclaim.c
+++ b/drivers/md/dm-zoned-reclaim.c
@@ -134,7 +134,7 @@ static int dmz_reclaim_copy(struct dmz_reclaim *zrc,
dst_zone_block = dmz_start_block(zmd, 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) {
if (src_zone->dev->flags & DMZ_BDEV_DYING)