This is a note to let you know that I've just added the patch titled
btrfs: move out now unused BG from the reclaim list
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
btrfs-move-out-now-unused-bg-from-the-reclaim-list.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d822ad0705cb53beec76fbb1c67670088f9199b6
Author: Naohiro Aota <naota@xxxxxxxxx>
Date: Tue Jun 6 14:36:34 2023 +0900
btrfs: move out now unused BG from the reclaim list
[ Upstream commit a9f189716cf15913c453299d72f69c51a9b0f86b ]
An unused block group is easy to remove to free up space and should be
reclaimed fast. Such block group can often already be a target of the
reclaim process. As we check list_empty(&bg->bg_list), we keep it in the
reclaim list. That block group is never reclaimed until the file system
is filled e.g. up to 75%.
Instead, we can move unused block group to the unused list and delete it
fast.
Fixes: 18bb8bbf13c1 ("btrfs: zoned: automatically reclaim zones")
CC: stable@xxxxxxxxxxxxxxx # 5.15+
Reviewed-by: Filipe Manana <fdmanana@xxxxxxxx>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Signed-off-by: Naohiro Aota <naohiro.aota@xxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index d24cef671c1aa..4ca6828586af5 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -1475,11 +1475,14 @@ void btrfs_mark_bg_unused(struct btrfs_block_group *bg)
{
struct btrfs_fs_info *fs_info = bg->fs_info;
+ trace_btrfs_add_unused_block_group(bg);
spin_lock(&fs_info->unused_bgs_lock);
if (list_empty(&bg->bg_list)) {
btrfs_get_block_group(bg);
- trace_btrfs_add_unused_block_group(bg);
list_add_tail(&bg->bg_list, &fs_info->unused_bgs);
+ } else {
+ /* Pull out the block group from the reclaim_bgs list. */
+ list_move_tail(&bg->bg_list, &fs_info->unused_bgs);
}
spin_unlock(&fs_info->unused_bgs_lock);
}
