diff options
Diffstat (limited to 'fs/btrfs/block-group.c')
-rw-r--r-- | fs/btrfs/block-group.c | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 0dcf7fecaf55..91440ef79a26 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1678,6 +1678,17 @@ void btrfs_reclaim_bgs_work(struct work_struct *work) up_write(&space_info->groups_sem); goto next; } + + /* + * Cache the zone_unusable value before turning the block group + * to read only. As soon as the block group is read only it's + * zone_unusable value gets moved to the block group's read-only + * bytes and isn't available for calculations anymore. We also + * cache it before unlocking the block group, to prevent races + * (reports from KCSAN and such tools) with tasks updating it. + */ + zone_unusable = bg->zone_unusable; + spin_unlock(&bg->lock); /* @@ -1693,13 +1704,6 @@ void btrfs_reclaim_bgs_work(struct work_struct *work) goto next; } - /* - * Cache the zone_unusable value before turning the block group - * to read only. As soon as the blog group is read only it's - * zone_unusable value gets moved to the block group's read-only - * bytes and isn't available for calculations anymore. - */ - zone_unusable = bg->zone_unusable; ret = inc_block_group_ro(bg, 0); up_write(&space_info->groups_sem); if (ret < 0) |