diff options
| author | Dennis Zhou (Facebook) | 2018-09-11 14:41:29 -0400 |
|---|---|---|
| committer | Jens Axboe | 2018-09-21 20:29:06 -0600 |
| commit | a7b39b4e961c4e2b3ed837803a7441a65c90ce33 (patch) | |
| tree | 7dda6dda4a341971504ccd16a44dbda27d57a0f8 /include/linux | |
| parent | 07b05bcc3213ac9f8c28c9d835b4bf3d5798cc60 (diff) | |
blkcg: always associate a bio with a blkg
Previously, blkg's were only assigned as needed by blk-iolatency and
blk-throttle. bio->css was also always being associated while blkg was
being looked up and then thrown away in blkcg_bio_issue_check.
This patch begins the cleanup of bio->css and bio->bi_blkg by always
associating a blkg in blkcg_bio_issue_check. This tries to create the
blkg, but if it is not possible, falls back to using the root_blkg of
the request_queue. Therefore, a bio will always be associated with a
blkg. The duplicate association logic is removed from blk-throttle and
blk-iolatency.
Signed-off-by: Dennis Zhou <dennisszhou@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/bio.h | 3 | ||||
| -rw-r--r-- | include/linux/blk-cgroup.h | 16 |
2 files changed, 5 insertions, 14 deletions
diff --git a/include/linux/bio.h b/include/linux/bio.h index 14b4fa266357..829cd0bb407d 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -542,11 +542,14 @@ static inline int bio_associate_blkcg_from_page(struct bio *bio, #ifdef CONFIG_BLK_CGROUP int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css); int bio_associate_blkg(struct bio *bio, struct blkcg_gq *blkg); +int bio_associate_create_blkg(struct request_queue *q, struct bio *bio); void bio_disassociate_task(struct bio *bio); void bio_clone_blkcg_association(struct bio *dst, struct bio *src); #else /* CONFIG_BLK_CGROUP */ static inline int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css) { return 0; } +static inline int bio_associate_create_blkg(struct request_queue *q, + struct bio *bio) { return 0; } static inline void bio_disassociate_task(struct bio *bio) { } static inline void bio_clone_blkcg_association(struct bio *dst, struct bio *src) { } diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index 1fbff1bbb651..6e33ad1d92b4 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -900,29 +900,17 @@ static inline bool blk_throtl_bio(struct request_queue *q, struct blkcg_gq *blkg static inline bool blkcg_bio_issue_check(struct request_queue *q, struct bio *bio) { - struct blkcg *blkcg; struct blkcg_gq *blkg; bool throtl = false; rcu_read_lock(); - /* associate blkcg if bio hasn't attached one */ - bio_associate_blkcg(bio, NULL); - blkcg = bio_blkcg(bio); - - blkg = blkg_lookup(blkcg, q); - if (unlikely(!blkg)) { - spin_lock_irq(q->queue_lock); - blkg = __blkg_lookup_create(blkcg, q); - if (IS_ERR(blkg)) - blkg = NULL; - spin_unlock_irq(q->queue_lock); - } + bio_associate_create_blkg(q, bio); + blkg = bio->bi_blkg; throtl = blk_throtl_bio(q, blkg, bio); if (!throtl) { - blkg = blkg ?: q->root_blkg; /* * If the bio is flagged with BIO_QUEUE_ENTERED it means this * is a split bio and we would have already accounted for the |