diff options
| author | Xiao Ni <xni@redhat.com> | 2023-02-03 13:13:44 +0800 |
|---|---|---|
| committer | Song Liu <song@kernel.org> | 2023-02-08 15:46:57 -0800 |
| commit | 76fed01420bb8b0e282745a4945925b25751d42b (patch) | |
| tree | cfd8694bedd41a4a5cb6a3a9c7899704182fcfe4 /drivers/md/md.c | |
| parent | 0abe39dec065133e3f92a52219c3728fe7d7617f (diff) | |
md: account io_acct_set usage with active_io
io_acct_set was enabled for raid0/raid5 io accounting. bios that contain
md_io_acct are allocated in the i/o path. There isn't a good method to
monitor if these bios are all finished and freed. In the takeover process,
io_acct_set (which is used for bios with md_io_acct) need to be freed.
However, if some bios finish after io_acct_set is freed, it may trigger
the following panic:
[ 6973.767999] RIP: 0010:mempool_free+0x52/0x80
[ 6973.786098] Call Trace:
[ 6973.786549] md_end_io_acct+0x31/0x40
[ 6973.787227] blk_update_request+0x224/0x380
[ 6973.787994] blk_mq_end_request+0x1a/0x130
[ 6973.788739] blk_complete_reqs+0x35/0x50
[ 6973.789456] __do_softirq+0xd7/0x2c8
[ 6973.790114] ? sort_range+0x20/0x20
[ 6973.790763] run_ksoftirqd+0x2a/0x40
[ 6973.791400] smpboot_thread_fn+0xb5/0x150
[ 6973.792114] kthread+0x10b/0x130
[ 6973.792724] ? set_kthread_struct+0x50/0x50
[ 6973.793491] ret_from_fork+0x1f/0x40
Fix this by increasing and decreasing active_io for each bio with
md_io_acct so that mddev_suspend() will wait until all bios from
io_acct_set finish before freeing io_acct_set.
Reported-by: Fine Fan <ffan@redhat.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Diffstat (limited to 'drivers/md/md.c')
| -rw-r--r-- | drivers/md/md.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 1961105712b7..927a43db5dfb 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -8628,12 +8628,15 @@ static void md_end_io_acct(struct bio *bio) { struct md_io_acct *md_io_acct = bio->bi_private; struct bio *orig_bio = md_io_acct->orig_bio; + struct mddev *mddev = md_io_acct->mddev; orig_bio->bi_status = bio->bi_status; bio_end_io_acct(orig_bio, md_io_acct->start_time); bio_put(bio); bio_endio(orig_bio); + + percpu_ref_put(&mddev->active_io); } /* @@ -8649,10 +8652,13 @@ void md_account_bio(struct mddev *mddev, struct bio **bio) if (!blk_queue_io_stat(bdev->bd_disk->queue)) return; + percpu_ref_get(&mddev->active_io); + clone = bio_alloc_clone(bdev, *bio, GFP_NOIO, &mddev->io_acct_set); md_io_acct = container_of(clone, struct md_io_acct, bio_clone); md_io_acct->orig_bio = *bio; md_io_acct->start_time = bio_start_io_acct(*bio); + md_io_acct->mddev = mddev; clone->bi_end_io = md_end_io_acct; clone->bi_private = md_io_acct; |