diff options
| author | Coly Li <colyli@suse.de> | 2019-06-28 14:59:47 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2019-06-28 16:39:16 +0300 |
| commit | 97ba3b816e2cdea798398bc8486125f79f2453c1 (patch) | |
| tree | 26e65edffab7d5f9a61d55eceef7a6449da427c6 | |
| parent | a59ff6ccc2bf2e2934b31bbf734f0bc04b5ec78a (diff) | |
| download | linux-97ba3b816e2cdea798398bc8486125f79f2453c1.tar.xz | |
bcache: acquire bch_register_lock later in cached_dev_detach_finish()
Now there is variable bcache_is_reboot to prevent device register or
unregister during reboot, it is unncessary to still hold mutex lock
bch_register_lock before stopping writeback_rate_update kworker and
writeback kthread. And if the stopping kworker or kthread holding
bch_register_lock inside their routine (we used to have such problem
in writeback thread, thanks to Junhui Wang fixed it), it is very easy
to introduce deadlock during reboot/shutdown procedure.
Therefore in this patch, the location to acquire bch_register_lock is
moved to the location before calling calc_cached_dev_sectors(). Which
is later then original location in cached_dev_detach_finish().
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | drivers/md/bcache/super.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index a88238ad5da1..40d857e690f9 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1018,7 +1018,6 @@ static void cached_dev_detach_finish(struct work_struct *w) BUG_ON(!test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags)); BUG_ON(refcount_read(&dc->count)); - mutex_lock(&bch_register_lock); if (test_and_clear_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags)) cancel_writeback_rate_update_dwork(dc); @@ -1034,6 +1033,8 @@ static void cached_dev_detach_finish(struct work_struct *w) bch_write_bdev_super(dc, &cl); closure_sync(&cl); + mutex_lock(&bch_register_lock); + calc_cached_dev_sectors(dc->disk.c); bcache_device_detach(&dc->disk); list_move(&dc->list, &uncached_devices); |