nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

blkcg: rename blkg_try_get to blkg_tryget

Browse source 
blkg reference counting now uses percpu_ref rather than atomic_t. Let's
make this consistent with css_tryget. This renames blkg_try_get to
blkg_tryget and now returns a bool rather than the blkg or NULL.

Signed-off-by: Dennis Zhou <dennisszhou@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Dennis Zhou (Facebook) 2018-09-11 14:41:37 -04:00 committed by Jens Axboe
parent b3b9f24f5f
commit 101246ec02
4 changed files with 9 additions and 12 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

2
block/bio.c
View file

@ -1974,7 +1974,7 @@ int bio_associate_blkg(struct bio *bio, struct blkcg_gq *blkg)
{ {
if (unlikely(bio->bi_blkg)) if (unlikely(bio->bi_blkg))
return -EBUSY; return -EBUSY;
bio->bi_blkg = blkg_try_get_closest(blkg); bio->bi_blkg = blkg_tryget_closest(blkg);
return 0; return 0;
} }

3
block/blk-cgroup.c
View file

@ -1794,8 +1794,7 @@ void blkcg_maybe_throttle_current(void)
blkg = blkg_lookup(blkcg, q); blkg = blkg_lookup(blkcg, q);
if (!blkg) if (!blkg)
goto out; goto out;
blkg = blkg_try_get(blkg); if (!blkg_tryget(blkg))
if (!blkg)
goto out; goto out;
rcu_read_unlock(); rcu_read_unlock();

2
block/blk-iolatency.c
View file

@ -625,7 +625,7 @@ static void blkiolatency_timer_fn(struct timer_list *t)
* We could be exiting, don't access the pd unless we have a * We could be exiting, don't access the pd unless we have a
* ref on the blkg. * ref on the blkg.
*/ */
if (!blkg_try_get(blkg)) if (!blkg_tryget(blkg))
continue; continue;
iolat = blkg_to_lat(blkg); iolat = blkg_to_lat(blkg);

14
include/linux/blk-cgroup.h
View file

@ -494,27 +494,25 @@ static inline void blkg_get(struct blkcg_gq *blkg)
} }
/** /**
* blkg_try_get - try and get a blkg reference * blkg_tryget - try and get a blkg reference
* @blkg: blkg to get * @blkg: blkg to get
* *
* This is for use when doing an RCU lookup of the blkg. We may be in the midst * This is for use when doing an RCU lookup of the blkg. We may be in the midst
* of freeing this blkg, so we can only use it if the refcnt is not zero. * of freeing this blkg, so we can only use it if the refcnt is not zero.
*/ */
static inline struct blkcg_gq *blkg_try_get(struct blkcg_gq *blkg) static inline bool blkg_tryget(struct blkcg_gq *blkg)
{ {
if (percpu_ref_tryget(&blkg->refcnt)) return percpu_ref_tryget(&blkg->refcnt);
return blkg;
return NULL;
} }
/** /**
* blkg_try_get_closest - try and get a blkg ref on the closet blkg * blkg_tryget_closest - try and get a blkg ref on the closet blkg
* @blkg: blkg to get * @blkg: blkg to get
* *
* This walks up the blkg tree to find the closest non-dying blkg and returns * This walks up the blkg tree to find the closest non-dying blkg and returns
* the blkg that it did association with as it may not be the passed in blkg. * the blkg that it did association with as it may not be the passed in blkg.
*/ */
static inline struct blkcg_gq *blkg_try_get_closest(struct blkcg_gq *blkg) static inline struct blkcg_gq *blkg_tryget_closest(struct blkcg_gq *blkg)
{ {
while (!percpu_ref_tryget(&blkg->refcnt)) while (!percpu_ref_tryget(&blkg->refcnt))
blkg = blkg->parent; blkg = blkg->parent;
@ -599,7 +597,7 @@ static inline struct request_list *blk_get_rl(struct request_queue *q,
if (unlikely(!blkg)) if (unlikely(!blkg))
blkg = __blkg_lookup_create(blkcg, q); blkg = __blkg_lookup_create(blkcg, q);
if (!blkg_try_get(blkg)) if (!blkg_tryget(blkg))
goto rl_use_root; goto rl_use_root;
rcu_read_unlock(); rcu_read_unlock();