diff options
| author | Johannes Thumshirn <johannes.thumshirn@wdc.com> | 2021-07-06 01:32:38 +0900 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2021-07-07 17:42:57 +0200 |
| commit | 9cc0b837e14ae913581ec1ea6e979a738f71b0fd (patch) | |
| tree | e7f7cb63b520e9a19809fe605d994343419e2832 /fs | |
| parent | abb99cfdaf0759f8a619e5fecf52ccccdf310c8c (diff) | |
btrfs: don't block if we can't acquire the reclaim lock
If we can't acquire the reclaim_bgs_lock on block group reclaim, we
block until it is free. This can potentially stall for a long time.
While reclaim of block groups is necessary for a good user experience on
a zoned file system, there still is no need to block as it is best
effort only, just like when we're deleting unused block groups.
CC: stable@vger.kernel.org # 5.13
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/block-group.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index c557327b4545..9e7d9d0c763d 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1498,7 +1498,15 @@ void btrfs_reclaim_bgs_work(struct work_struct *work) if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) return; - mutex_lock(&fs_info->reclaim_bgs_lock); + /* + * Long running balances can keep us blocked here for eternity, so + * simply skip reclaim if we're unable to get the mutex. + */ + if (!mutex_trylock(&fs_info->reclaim_bgs_lock)) { + btrfs_exclop_finish(fs_info); + return; + } + spin_lock(&fs_info->unused_bgs_lock); while (!list_empty(&fs_info->reclaim_bgs)) { u64 zone_unusable; |