writeback: fix WB_SYNC_NONE writeback from umount

Browse source

When umount calls sync_filesystem(), we first do a WB_SYNC_NONE
writeback to kick off writeback of pending dirty inodes, then follow
that up with a WB_SYNC_ALL to wait for it. Since umount already holds
the sb s_umount mutex, WB_SYNC_NONE ends up doing nothing and all
writeback happens as WB_SYNC_ALL. This can greatly slow down umount,
since WB_SYNC_ALL writeback is a data integrity operation and thus
a bigger hammer than simple WB_SYNC_NONE. For barrier aware file systems
it's a lot slower.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

...

This commit is contained in:

Jens Axboe 2010-05-17 12:55:07 +02:00

parent 69b62d01ec

commit e913fc825d

5 changed files with 51 additions and 15 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

48

fs/fs-writeback.c

View file

2

fs/sync.c

View file

2

include/linux/backing-dev.h

View file

10

include/linux/writeback.h

View file

4

mm/page-writeback.c

View file