writeback, blkcg: associate each blkcg_gq with the corresponding bdi_writeback_congested
authorTejun Heo <tj@kernel.org>
Fri, 22 May 2015 21:13:38 +0000 (17:13 -0400)
committerJens Axboe <axboe@fb.com>
Tue, 2 Jun 2015 14:33:35 +0000 (08:33 -0600)
commitce7acfeaf0363c8b75810908448f61af04d38f91
treed1f45850fc6a225662f1e959d26572f70539a24b
parent52ebea749aaed195245701a8f90a23d672c7a933
writeback, blkcg: associate each blkcg_gq with the corresponding bdi_writeback_congested

A blkg (blkcg_gq) can be congested and decongested independently from
other blkgs on the same request_queue.  Accordingly, for cgroup
writeback support, the congestion status at bdi (backing_dev_info)
should be split and updated separately from matching blkg's.

This patch prepares by adding blkg->wb_congested and associating a
blkg with its matching per-blkcg bdi_writeback_congested on creation.

v2: Updated to associate bdi_writeback_congested instead of
    bdi_writeback.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
block/blk-cgroup.c
include/linux/blk-cgroup.h