diff options
author | NeilBrown <neilb@suse.com> | 2017-04-05 14:05:51 +1000 |
---|---|---|
committer | Shaohua Li <shli@fb.com> | 2017-04-11 10:16:50 -0700 |
commit | dd7a8f5dee81ffb1794df1103f07c63fd4f1d766 (patch) | |
tree | 75548d262b86202ad305a47491522c499098c783 | |
parent | 545250f2480911f053b092d4229d9f83a9dff222 (diff) | |
download | linux-dd7a8f5dee81ffb1794df1103f07c63fd4f1d766.tar.bz2 |
md/raid5: make chunk_aligned_read() split bios more cleanly.
chunk_aligned_read() currently uses fs_bio_set - which is meant for
filesystems to use - and loops if multiple splits are needed, which is
not best practice.
As this is only used for READ requests, not writes, it is unlikely
to cause a problem. However it is best to be consistent in how
we split bios, and to follow the pattern used in raid1/raid10.
So create a private bioset, bio_split, and use it to perform a single
split, submitting the remainder to generic_make_request() for later
processing.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
-rw-r--r-- | drivers/md/raid5.c | 33 | ||||
-rw-r--r-- | drivers/md/raid5.h | 1 |
2 files changed, 18 insertions, 16 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index f3692ff4262b..356cd9c7c753 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5246,24 +5246,20 @@ static int raid5_read_one_chunk(struct mddev *mddev, struct bio *raid_bio) static struct bio *chunk_aligned_read(struct mddev *mddev, struct bio *raid_bio) { struct bio *split; + sector_t sector = raid_bio->bi_iter.bi_sector; + unsigned chunk_sects = mddev->chunk_sectors; + unsigned sectors = chunk_sects - (sector & (chunk_sects-1)); - do { - sector_t sector = raid_bio->bi_iter.bi_sector; - unsigned chunk_sects = mddev->chunk_sectors; - unsigned sectors = chunk_sects - (sector & (chunk_sects-1)); - - if (sectors < bio_sectors(raid_bio)) { - split = bio_split(raid_bio, sectors, GFP_NOIO, fs_bio_set); - bio_chain(split, raid_bio); - } else - split = raid_bio; + if (sectors < bio_sectors(raid_bio)) { + struct r5conf *conf = mddev->private; + split = bio_split(raid_bio, sectors, GFP_NOIO, conf->bio_split); + bio_chain(split, raid_bio); + generic_make_request(raid_bio); + raid_bio = split; + } - if (!raid5_read_one_chunk(mddev, split)) { - if (split != raid_bio) - generic_make_request(raid_bio); - return split; - } - } while (split != raid_bio); + if (!raid5_read_one_chunk(mddev, raid_bio)) + return raid_bio; return NULL; } @@ -6747,6 +6743,8 @@ static void free_conf(struct r5conf *conf) if (conf->disks[i].extra_page) put_page(conf->disks[i].extra_page); kfree(conf->disks); + if (conf->bio_split) + bioset_free(conf->bio_split); kfree(conf->stripe_hashtbl); kfree(conf->pending_data); kfree(conf); @@ -6922,6 +6920,9 @@ static struct r5conf *setup_conf(struct mddev *mddev) goto abort; } + conf->bio_split = bioset_create(BIO_POOL_SIZE, 0); + if (!conf->bio_split) + goto abort; conf->mddev = mddev; if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL) diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h index cdc7f92e1806..625c7f16fd6b 100644 --- a/drivers/md/raid5.h +++ b/drivers/md/raid5.h @@ -646,6 +646,7 @@ struct r5conf { int pool_size; /* number of disks in stripeheads in pool */ spinlock_t device_lock; struct disk_info *disks; + struct bio_set *bio_split; /* When taking over an array from a different personality, we store * the new thread here until we fully activate the array. |