diff options
| -rw-r--r-- | fs/btrfs/block-group.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 7dba9028c80c..de9aeb3733cf 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 +#include <linux/list_sort.h> #include "misc.h" #include "ctree.h" #include "block-group.h" @@ -1486,6 +1487,21 @@ void btrfs_mark_bg_unused(struct btrfs_block_group *bg) spin_unlock(&fs_info->unused_bgs_lock); } +/* + * We want block groups with a low number of used bytes to be in the beginning + * of the list, so they will get reclaimed first. + */ +static int reclaim_bgs_cmp(void *unused, const struct list_head *a, + const struct list_head *b) +{ + const struct btrfs_block_group *bg1, *bg2; + + bg1 = list_entry(a, struct btrfs_block_group, bg_list); + bg2 = list_entry(b, struct btrfs_block_group, bg_list); + + return bg1->used > bg2->used; +} + void btrfs_reclaim_bgs_work(struct work_struct *work) { struct btrfs_fs_info *fs_info = @@ -1510,6 +1526,12 @@ void btrfs_reclaim_bgs_work(struct work_struct *work) } spin_lock(&fs_info->unused_bgs_lock); + /* + * Sort happens under lock because we can't simply splice it and sort. + * The block groups might still be in use and reachable via bg_list, + * and their presence in the reclaim_bgs list must be preserved. + */ + list_sort(NULL, &fs_info->reclaim_bgs, reclaim_bgs_cmp); while (!list_empty(&fs_info->reclaim_bgs)) { u64 zone_unusable; int ret = 0; |