diff options
| -rw-r--r-- | fs/btrfs/block-group.c | 55 |
1 files changed, 31 insertions, 24 deletions
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 221df35da49b..a8129f1ce78c 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1456,6 +1456,32 @@ out: } /* + * Link the block_group to a list via bg_list. + * + * @bg: The block_group to link to the list. + * @list: The list to link it to. + * + * Use this rather than list_add_tail() directly to ensure proper respect + * to locking and refcounting. + * + * Returns: true if the bg was linked with a refcount bump and false otherwise. + */ +static bool btrfs_link_bg_list(struct btrfs_block_group *bg, struct list_head *list) +{ + struct btrfs_fs_info *fs_info = bg->fs_info; + bool added = false; + + spin_lock(&fs_info->unused_bgs_lock); + if (list_empty(&bg->bg_list)) { + btrfs_get_block_group(bg); + list_add_tail(&bg->bg_list, list); + added = true; + } + spin_unlock(&fs_info->unused_bgs_lock); + return added; +} + +/* * Process the unused_bgs list and remove any that don't have any allocated * space inside of them. */ @@ -1570,8 +1596,7 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info) * drop under the "next" label for the * fs_info->unused_bgs list. */ - btrfs_get_block_group(block_group); - list_add_tail(&block_group->bg_list, &retry_list); + btrfs_link_bg_list(block_group, &retry_list); trace_btrfs_skip_unused_block_group(block_group); spin_unlock(&block_group->lock); @@ -1968,20 +1993,8 @@ void btrfs_reclaim_bgs_work(struct work_struct *work) spin_unlock(&space_info->lock); next: - if (ret && !READ_ONCE(space_info->periodic_reclaim)) { - /* Refcount held by the reclaim_bgs list after splice. */ - spin_lock(&fs_info->unused_bgs_lock); - /* - * This block group might be added to the unused list - * during the above process. Move it back to the - * reclaim list otherwise. - */ - if (list_empty(&bg->bg_list)) { - btrfs_get_block_group(bg); - list_add_tail(&bg->bg_list, &retry_list); - } - spin_unlock(&fs_info->unused_bgs_lock); - } + if (ret && !READ_ONCE(space_info->periodic_reclaim)) + btrfs_link_bg_list(bg, &retry_list); btrfs_put_block_group(bg); mutex_unlock(&fs_info->reclaim_bgs_lock); @@ -2021,13 +2034,8 @@ void btrfs_mark_bg_to_reclaim(struct btrfs_block_group *bg) { struct btrfs_fs_info *fs_info = bg->fs_info; - spin_lock(&fs_info->unused_bgs_lock); - if (list_empty(&bg->bg_list)) { - btrfs_get_block_group(bg); + if (btrfs_link_bg_list(bg, &fs_info->reclaim_bgs)) trace_btrfs_add_reclaim_block_group(bg); - list_add_tail(&bg->bg_list, &fs_info->reclaim_bgs); - } - spin_unlock(&fs_info->unused_bgs_lock); } static int read_bg_from_eb(struct btrfs_fs_info *fs_info, const struct btrfs_key *key, @@ -2940,8 +2948,7 @@ struct btrfs_block_group *btrfs_make_block_group(struct btrfs_trans_handle *tran } #endif - btrfs_get_block_group(cache); - list_add_tail(&cache->bg_list, &trans->new_bgs); + btrfs_link_bg_list(cache, &trans->new_bgs); btrfs_inc_delayed_refs_rsv_bg_inserts(fs_info); set_avail_alloc_bits(fs_info, type); |