commit 2d192fc4c1abeb0d04d1c8cd54405ff4a0b0255b upstream. There is a user report about "btrfs filesystem defrag" causing 120s timeout problem. For btrfs_defrag_file() it will iterate all file extents if called from defrag ioctl, thus it can take a long time. There is no reason not to release the CPU during such a long operation. Add cond_resched() after defragged one cluster. CC: stable@xxxxxxxxxxxxxxx # 5.15 Link: https://lore.kernel.org/linux-btrfs/10e51417-2203-f0a4-2021-86c8511cc367@xxxxxxx Signed-off-by: Qu Wenruo <wqu@xxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> --- fs/btrfs/ioctl.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 6a863b3f6de0..38a1b68c7851 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1581,6 +1581,7 @@ int btrfs_defrag_file(struct inode *inode, struct file *file, last_len = 0; } } + cond_resched(); } ret = defrag_count; -- 2.35.1
