diff mbox series

[for,v5.15,1/2] btrfs: don't hold CPU for too long when defragging a file

Message ID 67dd6f0e69c59a8554d7a2977939f94221af00c1.1644994950.git.wqu@suse.com
State New
Headers show
Series [for,v5.15,1/2] btrfs: don't hold CPU for too long when defragging a file | expand

Commit Message

Qu Wenruo Feb. 16, 2022, 7:09 a.m. UTC 
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@vger.kernel.org # 5.15
Link: https://lore.kernel.org/linux-btrfs/10e51417-2203-f0a4-2021-86c8511cc367@gmx.com
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/ioctl.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Qu Wenruo Feb. 18, 2022, 12:06 a.m. UTC | #1 
On 2022/2/18 03:48, Greg KH wrote:
> On Thu, Feb 17, 2022 at 08:41:51PM +0100, Holger Hoffstätte wrote:
>> On 2022-02-17 20:01, Greg KH wrote:
>>> On Wed, Feb 16, 2022 at 03:09:07PM +0800, Qu Wenruo wrote:
>>>> commit 2d192fc4c1abeb0d04d1c8cd54405ff4a0b0255b upstream.
>>>
>>> This commit is already in 5.15.22.
>>
>> It most certainly is not
>
> Commit 2d192fc4c1abeb0d04d1c8cd54405ff4a0b0255b is in 5.15.22.
>
>> since it applies cleanly in 5.15.24.
>> The correct upstream commit of this patch is ea0eba69a2a8125229b1b6011644598039bc53aa
>
> Ah, no wonder the confusion.  For obvious reasons, I can not take this
> as-is :)

My bad, wrong commit hash...

>
> thanks,
>
> greg k-h
diff mbox series

Patch

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;