mpage: make __mpage_writepage() honor cgroup writeback
__mpage_writepage() is used to implement mpage_writepages() which in
turn is used for ->writepages() of various filesystems. All writeback
logic is now updated to handle cgroup writeback and the block cgroup
to issue IOs for is encoded in writeback_control and can be retrieved
using wbc_blkcg_css(); however, __mpage_writepage() currently ignores
the blkcg indicated by wbc and issues all bio's without explicit blkcg
association.
This patch updates __mpage_writepage() so that the issued bio's are
associated with wbc_blkcg_css().
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/mpage.c b/fs/mpage.c
index 587c7ed..84921b2 100644
--- a/fs/mpage.c
+++ b/fs/mpage.c
@@ -595,6 +595,8 @@
alloc_new:
if (bio == NULL) {
+ struct cgroup_subsys_state *blkcg_css;
+
if (first_unmapped == blocks_per_page) {
if (!bdev_write_page(bdev, blocks[0] << (blkbits - 9),
page, wbc)) {
@@ -606,6 +608,10 @@
bio_get_nr_vecs(bdev), GFP_NOFS|__GFP_HIGH);
if (bio == NULL)
goto confused;
+
+ blkcg_css = wbc_blkcg_css(wbc);
+ if (blkcg_css)
+ bio_associate_blkcg(bio, blkcg_css);
}
/*
