diff options
| author |   NeilBrown <neilb@suse.de> | 2006-05-01 12:15:47 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@g5.osdl.org> | 2006-05-01 18:17:42 -0700 |
| commit | 5e7dd2ab6b9bdfa60e19b8739e6b2a204fd4f477 (patch) | |
| tree | f9d3ac455ea67f1ea23e7e41848ac422506c474b /drivers/md | |
| parent | [PATCH] md: Improve detection of lack of barrier support in raid1 (diff) | |
| download | linux-dev-5e7dd2ab6b9bdfa60e19b8739e6b2a204fd4f477.tar.xz linux-dev-5e7dd2ab6b9bdfa60e19b8739e6b2a204fd4f477.zip | |
[PATCH] md: Fix 'rdev->nr_pending' count when retrying barrier requests
When retrying a failed BIO_RW_BARRIER request, we need to keep the reference
in ->nr_pending over the whole retry. Currently, we only hold the reference
if the failed request is the *last* one to finish - which is silly, because it
would normally be the first to finish.
So move the rdev_dec_pending call up into the didn't-fail branch. As the rdev
isn't used in the later code, calling rdev_dec_pending earlier doesn't hurt.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/raid1.c | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index b8c13c897ccb..4070eff6f0f8 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -319,6 +319,7 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int set_bit(BarriersNotsupp, &conf->mirrors[mirror].rdev->flags); set_bit(R1BIO_BarrierRetry, &r1_bio->state); r1_bio->mddev->barriers_work = 0; + /* Don't rdev_dec_pending in this branch - keep it for the retry */ } else { /* * this branch is our 'one mirror IO has finished' event handler: @@ -365,6 +366,7 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int } } } + rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); } /* * @@ -374,11 +376,9 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int if (atomic_dec_and_test(&r1_bio->remaining)) { if (test_bit(R1BIO_BarrierRetry, &r1_bio->state)) { reschedule_retry(r1_bio); - /* Don't dec_pending yet, we want to hold - * the reference over the retry - */ goto out; } + /* it really is the end of this request */ if (test_bit(R1BIO_BehindIO, &r1_bio->state)) { /* free extra copy of the data pages */ int i = bio->bi_vcnt; @@ -393,8 +393,6 @@ static int raid1_end_write_request(struct bio *bio, unsigned int bytes_done, int md_write_end(r1_bio->mddev); raid_end_bio_io(r1_bio); } - - rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); out: if (to_put) bio_put(to_put); @@ -1414,6 +1412,7 @@ static void raid1d(mddev_t *mddev) * Better resubmit without the barrier. * We know which devices to resubmit for, because * all others have had their bios[] entry cleared. + * We already have a nr_pending reference on these rdevs. */ int i; clear_bit(R1BIO_BarrierRetry, &r1_bio->state); |