This is a note to let you know that I've just added the patch titled
btrfs: reset block group chunk force if we have to wait
to the 5.4-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-reset-block-group-chunk-force-if-we-have-to-wait.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 1314ca78b2c35d3e7d0f097268a2ee6dc0d369ef Mon Sep 17 00:00:00 2001
From: Josef Bacik <josef@xxxxxxxxxxxxxx>
Date: Mon, 13 Jun 2022 18:31:17 -0400
Subject: btrfs: reset block group chunk force if we have to wait
From: Josef Bacik <josef@xxxxxxxxxxxxxx>
commit 1314ca78b2c35d3e7d0f097268a2ee6dc0d369ef upstream.
If you try to force a chunk allocation, but you race with another chunk
allocation, you will end up waiting on the chunk allocation that just
occurred and then allocate another chunk. If you have many threads all
doing this at once you can way over-allocate chunks.
Fix this by resetting force to NO_FORCE, that way if we think we need to
allocate we can, otherwise we don't force another chunk allocation if
one is already happening.
Reviewed-by: Filipe Manana <fdmanana@xxxxxxxx>
CC: stable@xxxxxxxxxxxxxxx # 5.4+
Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/block-group.c | 1 +
1 file changed, 1 insertion(+)
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -2938,6 +2938,7 @@ int btrfs_chunk_alloc(struct btrfs_trans
* attempt.
*/
wait_for_alloc = true;
+ force = CHUNK_ALLOC_NO_FORCE;
spin_unlock(&space_info->lock);
mutex_lock(&fs_info->chunk_mutex);
mutex_unlock(&fs_info->chunk_mutex);
Patches currently in stable-queue which might be from josef@xxxxxxxxxxxxxx are
queue-5.4/btrfs-reset-block-group-chunk-force-if-we-have-to-wait.patch
