leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Btrfs: remove rcu_barrier in btrfs_close_devices

Browse Source 
It was introduced because btrfs used to do blkdev_put in a deferred
work, now that btrfs has blkdev_put in place, this rcu_barrier can be
removed.

modprobe -r btrfs will do btrfs_cleanup_fs_uuids(), where it cleanup
every %fs_devices on the list, but when we do btrfs_close_devices(), we
have replaced the devices on the list with dummy ones which only have
the same name and uuid, so modprobe -r btrfs will free those instead of
what we were using, this change won't cause a problem for it.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ copied 2nd paragraph from mailinglist discussion ]
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Liu Bo 2017-10-10 15:51:02 -06:00 committed by David Sterba
parent 8577787fac
commit 47dba17171
1 changed files with 0 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
fs/btrfs/volumes.c
View File

@ -936,12 +936,6 @@ int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
__btrfs_close_devices(fs_devices); __btrfs_close_devices(fs_devices);
free_fs_devices(fs_devices); free_fs_devices(fs_devices);
} }
/*
* Wait for rcu kworkers under __btrfs_close_devices
* to finish all blkdev_puts so device is really
* free when umount is done.
*/
rcu_barrier();
return ret; return ret;
} }