diff options
| author | Yu Kuai <yukuai3@huawei.com> | 2023-05-29 16:11:06 +0300 |
|---|---|---|
| committer | Song Liu <song@kernel.org> | 2023-06-14 01:25:44 +0300 |
| commit | 460af1f9d9e62acce4a21f9bd00b5bcd5963bcd4 (patch) | |
| tree | ff7b4f55aac50289863c129e1d5a8e4ce1c3ce42 | |
| parent | 9efcc2c3df7612eea02daa159ae7c6ac44420513 (diff) | |
| download | linux-460af1f9d9e62acce4a21f9bd00b5bcd5963bcd4.tar.xz | |
md/raid1-10: limit the number of plugged bio
bio can be added to plug infinitely, and following writeback test can
trigger huge amount of plugged bio:
Test script:
modprobe brd rd_nr=4 rd_size=10485760
mdadm -CR /dev/md0 -l10 -n4 /dev/ram[0123] --assume-clean --bitmap=internal
echo 0 > /proc/sys/vm/dirty_background_ratio
fio -filename=/dev/md0 -ioengine=libaio -rw=write -bs=4k -numjobs=1 -iodepth=128 -name=test
Test result:
Monitor /sys/block/md0/inflight will found that inflight keep increasing
until fio finish writing, after running for about 2 minutes:
[root@fedora ~]# cat /sys/block/md0/inflight
0 4474191
Fix the problem by limiting the number of plugged bio based on the number
of copies for original bio.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230529131106.2123367-8-yukuai1@huaweicloud.com
| -rw-r--r-- | drivers/md/raid1-10.c | 9 | ||||
| -rw-r--r-- | drivers/md/raid1.c | 2 | ||||
| -rw-r--r-- | drivers/md/raid10.c | 2 |
3 files changed, 10 insertions, 3 deletions
diff --git a/drivers/md/raid1-10.c b/drivers/md/raid1-10.c index c62bcb17c67b..169ebe296f2d 100644 --- a/drivers/md/raid1-10.c +++ b/drivers/md/raid1-10.c @@ -21,6 +21,7 @@ #define IO_MADE_GOOD ((struct bio *)2) #define BIO_SPECIAL(bio) ((unsigned long)bio <= 2) +#define MAX_PLUG_BIO 32 /* for managing resync I/O pages */ struct resync_pages { @@ -31,6 +32,7 @@ struct resync_pages { struct raid1_plug_cb { struct blk_plug_cb cb; struct bio_list pending; + unsigned int count; }; static void rbio_pool_free(void *rbio, void *data) @@ -129,7 +131,7 @@ static inline void raid1_submit_write(struct bio *bio) } static inline bool raid1_add_bio_to_plug(struct mddev *mddev, struct bio *bio, - blk_plug_cb_fn unplug) + blk_plug_cb_fn unplug, int copies) { struct raid1_plug_cb *plug = NULL; struct blk_plug_cb *cb; @@ -149,6 +151,11 @@ static inline bool raid1_add_bio_to_plug(struct mddev *mddev, struct bio *bio, plug = container_of(cb, struct raid1_plug_cb, cb); bio_list_add(&plug->pending, bio); + if (++plug->count / MAX_PLUG_BIO >= copies) { + list_del(&cb->list); + cb->callback(cb, false); + } + return true; } diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 334ed76d3c5a..dd25832eb045 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1565,7 +1565,7 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, r1_bio->sector); /* flush_pending_writes() needs access to the rdev so...*/ mbio->bi_bdev = (void *)rdev; - if (!raid1_add_bio_to_plug(mddev, mbio, raid1_unplug)) { + if (!raid1_add_bio_to_plug(mddev, mbio, raid1_unplug, disks)) { spin_lock_irqsave(&conf->device_lock, flags); bio_list_add(&conf->pending_bio_list, mbio); spin_unlock_irqrestore(&conf->device_lock, flags); diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index f890f549086b..d0de8c9fb3cf 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1314,7 +1314,7 @@ static void raid10_write_one_disk(struct mddev *mddev, struct r10bio *r10_bio, atomic_inc(&r10_bio->remaining); - if (!raid1_add_bio_to_plug(mddev, mbio, raid10_unplug)) { + if (!raid1_add_bio_to_plug(mddev, mbio, raid10_unplug, conf->copies)) { spin_lock_irqsave(&conf->device_lock, flags); bio_list_add(&conf->pending_bio_list, mbio); spin_unlock_irqrestore(&conf->device_lock, flags); |