blkcg: rename blkg_try_get() to blkg_tryget()

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 <dennis@kernel.org>
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 2018-12-05 12:10:39 -05:00 committed by Jens Axboe
parent 7fcf2b033b
commit 7754f669ff
4 changed files with 8 additions and 11 deletions

View File

@ -1990,7 +1990,7 @@ static void __bio_associate_blkg(struct bio *bio, struct blkcg_gq *blkg)
{
bio_disassociate_blkg(bio);
bio->bi_blkg = blkg_try_get_closest(blkg);
bio->bi_blkg = blkg_tryget_closest(blkg);
}
/**

View File

@ -1736,8 +1736,7 @@ void blkcg_maybe_throttle_current(void)
blkg = blkg_lookup(blkcg, q);
if (!blkg)
goto out;
blkg = blkg_try_get(blkg);
if (!blkg)
if (!blkg_tryget(blkg))
goto out;
rcu_read_unlock();

View File

@ -698,7 +698,7 @@ static void blkiolatency_timer_fn(struct timer_list *t)
* We could be exiting, don't access the pd unless we have a
* ref on the blkg.
*/
if (!blkg_try_get(blkg))
if (!blkg_tryget(blkg))
continue;
iolat = blkg_to_lat(blkg);

View File

@ -491,27 +491,25 @@ 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
*
* 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.
*/
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 blkg;
return NULL;
return percpu_ref_tryget(&blkg->refcnt);
}
/**
* 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
*
* 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.
*/
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))
blkg = blkg->parent;