From: Goldwyn Rodrigues <rgold...@suse.com>
Bail and status to EAGAIN if raid10 is going to wait for:
+ barriers
+ reshape operation
+ Too many queued requests
Signed-off-by: Goldwyn Rodrigues <rgold...@suse.com>
---
drivers/md/raid10.c | 62 ++++++++++++++++++++++++++++++++++++++++-------------
1 file changed, 47 insertions(+), 15 deletions(-)
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 5026e7ad51d3..6d80438c5040 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -978,8 +978,9 @@ static void lower_barrier(struct r10conf *conf)
wake_up(&conf->wait_barrier);
}
-static void wait_barrier(struct r10conf *conf)
+static bool wait_barrier(struct r10conf *conf, bool nowait)
{
+ bool ret = true;
spin_lock_irq(&conf->resync_lock);
if (conf->barrier) {
conf->nr_waiting++;
@@ -993,19 +994,23 @@ static void wait_barrier(struct r10conf *conf)
* count down.
*/
raid10_log(conf->mddev, "wait barrier");
- wait_event_lock_irq(conf->wait_barrier,
- !conf->barrier ||
- (atomic_read(&conf->nr_pending) &&
- current->bio_list &&
- (!bio_list_empty(¤t->bio_list[0]) ||
- !bio_list_empty(¤t->bio_list[1]))),
- conf->resync_lock);
+ if (!nowait)
+ wait_event_lock_irq(conf->wait_barrier,
+ !conf->barrier ||
+ (atomic_read(&conf->nr_pending) &&
+ current->bio_list &&
+
(!bio_list_empty(¤t->bio_list[0]) ||
+
!bio_list_empty(¤t->bio_list[1]))),
+ conf->resync_lock);
+ else
+ ret = false;
conf->nr_waiting--;
if (!conf->nr_waiting)
wake_up(&conf->wait_barrier);
}
atomic_inc(&conf->nr_pending);
spin_unlock_irq(&conf->resync_lock);
+ return ret;
}
static void allow_barrier(struct r10conf *conf)
@@ -1158,7 +1163,10 @@ static void raid10_read_request(struct mddev *mddev,
struct bio *bio,
* thread has put up a bar for new requests.
* Continue immediately if no resync is active currently.
*/
- wait_barrier(conf);
+ if (!wait_barrier(conf, bio->bi_opf & REQ_NOWAIT)) {
+ bio_wouldblock_error(bio);
+ return;
+ }
sectors = r10_bio->sectors;
while (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
@@ -1169,12 +1177,16 @@ static void raid10_read_request(struct mddev *mddev,
struct bio *bio,
* pass
*/
raid10_log(conf->mddev, "wait reshape");
+ if (bio->bi_opf & REQ_NOWAIT) {
+ bio_wouldblock_error(bio);
+ return;
+ }
allow_barrier(conf);
wait_event(conf->wait_barrier,
conf->reshape_progress <= bio->bi_iter.bi_sector ||
conf->reshape_progress >= bio->bi_iter.bi_sector +
sectors);
- wait_barrier(conf);
+ wait_barrier(conf, false);
}
rdev = read_balance(conf, r10_bio, &max_sectors);
@@ -1308,7 +1320,10 @@ static void raid10_write_request(struct mddev *mddev,
struct bio *bio,
* thread has put up a bar for new requests.
* Continue immediately if no resync is active currently.
*/
- wait_barrier(conf);
+ if (!wait_barrier(conf, bio->bi_opf & REQ_NOWAIT)) {
+ bio_wouldblock_error(bio);
+ return;
+ }
sectors = r10_bio->sectors;
while (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
@@ -1319,12 +1334,16 @@ static void raid10_write_request(struct mddev *mddev,
struct bio *bio,
* pass
*/
raid10_log(conf->mddev, "wait reshape");
+ if (bio->bi_opf & REQ_NOWAIT) {
+ bio_wouldblock_error(bio);
+ return;
+ }
allow_barrier(conf);
wait_event(conf->wait_barrier,
conf->reshape_progress <= bio->bi_iter.bi_sector ||
conf->reshape_progress >= bio->bi_iter.bi_sector +
sectors);
- wait_barrier(conf);
+ wait_barrier(conf, false);
}
if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
@@ -1339,6 +1358,10 @@ static void raid10_write_request(struct mddev *mddev,
struct bio *bio,
BIT(MD_SB_CHANGE_DEVS) |
BIT(MD_SB_CHANGE_PENDING));
md_wakeup_thread(mddev->thread);
raid10_log(conf->mddev, "wait reshape metadata");
+ if (bio->bi_opf & REQ_NOWAIT) {
+ bio_wouldblock_error(bio);
+ return;
+ }
wait_event(mddev->sb_wait,
!test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags));
@@ -1348,6 +1371,10 @@ static void raid10_write_request(struct mddev *mddev,
struct bio *bio,
if (conf->pending_count >= max_queued_requests) {
md_wakeup_thread(mddev->thread);
raid10_log(mddev, "wait queued");
+ if (bio->bi_opf & REQ_NOWAIT) {
+ bio_wouldblock_error(bio);
+ return;
+ }
wait_event(conf->wait_barrier,
conf->pending_count < max_queued_requests);
}
@@ -1454,6 +1481,11 @@ static void raid10_write_request(struct mddev *mddev,
struct bio *bio,
int j;
int d;
+ if (bio->bi_opf & REQ_NOWAIT) {
+ bio_wouldblock_error(bio);
+ return;
+ }
+
for (j = 0; j < i; j++) {
if (r10_bio->devs[j].bio) {
d = r10_bio->devs[j].devnum;
@@ -1474,7 +1506,7 @@ static void raid10_write_request(struct mddev *mddev,
struct bio *bio,
allow_barrier(conf);
raid10_log(conf->mddev, "wait rdev %d blocked",
blocked_rdev->raid_disk);
md_wait_for_blocked_rdev(blocked_rdev, mddev);
- wait_barrier(conf);
+ wait_barrier(conf, false);
goto retry_write;
}
@@ -1703,7 +1735,7 @@ static void print_conf(struct r10conf *conf)
static void close_sync(struct r10conf *conf)
{
- wait_barrier(conf);
+ wait_barrier(conf, false);
allow_barrier(conf);
mempool_destroy(conf->r10buf_pool);
@@ -4347,7 +4379,7 @@ static sector_t reshape_request(struct mddev *mddev,
sector_t sector_nr,
if (need_flush ||
time_after(jiffies, conf->reshape_checkpoint + 10*HZ)) {
/* Need to update reshape_position in metadata */
- wait_barrier(conf);
+ wait_barrier(conf, false);
mddev->reshape_position = conf->reshape_progress;
if (mddev->reshape_backwards)
mddev->curr_resync_completed = raid10_size(mddev, 0, 0)
--
2.12.3
--
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