btrfs: avoid monopolizing a core when activating a swap file

commit 2c8507c63f5498d4ee4af404a8e44ceae4345056 upstream.

During swap activation we iterate over the extents of a file and we can
have many thousands of them, so we can end up in a busy loop monopolizing
a core. Avoid this by doing a voluntary reschedule after processing each
extent.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Filipe Manana 2024-12-09 16:43:44 +00:00 committed by Greg Kroah-Hartman
parent 30080cdde6
commit 3d770d44dd

View file

@ -7679,6 +7679,8 @@ noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
ret = -EAGAIN; ret = -EAGAIN;
goto out; goto out;
} }
cond_resched();
} }
btrfs_release_path(path); btrfs_release_path(path);