diff options
author | Tejun Heo <tj@kernel.org> | 2015-08-18 14:55:18 -0700 |
---|---|---|
committer | Jens Axboe <axboe@fb.com> | 2015-08-18 15:49:17 -0700 |
commit | 85b6bc9db6d5ab6980b43c38b5cbd11d24414ce4 (patch) | |
tree | 7389d8656738b72cc7c8c7569247db31800d9246 /include/linux/blk-cgroup.h | |
parent | 24f290466f79a6497f1654f64b9a841872cba3ca (diff) | |
download | blackbird-op-linux-85b6bc9db6d5ab6980b43c38b5cbd11d24414ce4.tar.gz blackbird-op-linux-85b6bc9db6d5ab6980b43c38b5cbd11d24414ce4.zip |
blkcg: move root blkg lookup optimization from throtl_lookup_tg() to __blkg_lookup()
Currently, both throttle and cfq policies implement their own root
blkg (blkcg_gq) lookup fast path. This patch moves root blkg
optimization from throtl_lookup_tg() to __blkg_lookup(). cfq-iosched
currently doesn't use blkg_lookup() but will be converted and drop the
optimization too.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Arianna Avanzini <avanzini.arianna@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'include/linux/blk-cgroup.h')
-rw-r--r-- | include/linux/blk-cgroup.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index d5b54aa50582..0609bce69f68 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -249,6 +249,9 @@ static inline struct blkcg_gq *__blkg_lookup(struct blkcg *blkcg, { struct blkcg_gq *blkg; + if (blkcg == &blkcg_root) + return q->root_blkg; + blkg = rcu_dereference(blkcg->blkg_hint); if (blkg && blkg->q == q) return blkg; |