diff options
Diffstat (limited to 'block/blk-cgroup.h')
| -rw-r--r-- | block/blk-cgroup.h | 17 |
1 files changed, 7 insertions, 10 deletions
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index cbb7f943f78a..1c401b057151 100644 --- a/block/blk-cgroup.h +++ b/block/blk-cgroup.h @@ -18,6 +18,7 @@ #include <linux/seq_file.h> #include <linux/radix-tree.h> #include <linux/blkdev.h> +#include <linux/atomic.h> /* Max limits for throttle policy */ #define THROTL_IOPS_MAX UINT_MAX @@ -104,7 +105,7 @@ struct blkcg_gq { struct request_list rl; /* reference count */ - int refcnt; + atomic_t refcnt; /* is this blkg online? protected by both blkcg and q locks */ bool online; @@ -257,13 +258,12 @@ static inline int blkg_path(struct blkcg_gq *blkg, char *buf, int buflen) * blkg_get - get a blkg reference * @blkg: blkg to get * - * The caller should be holding queue_lock and an existing reference. + * The caller should be holding an existing reference. */ static inline void blkg_get(struct blkcg_gq *blkg) { - lockdep_assert_held(blkg->q->queue_lock); - WARN_ON_ONCE(!blkg->refcnt); - blkg->refcnt++; + WARN_ON_ONCE(atomic_read(&blkg->refcnt) <= 0); + atomic_inc(&blkg->refcnt); } void __blkg_release_rcu(struct rcu_head *rcu); @@ -271,14 +271,11 @@ void __blkg_release_rcu(struct rcu_head *rcu); /** * blkg_put - put a blkg reference * @blkg: blkg to put - * - * The caller should be holding queue_lock. */ static inline void blkg_put(struct blkcg_gq *blkg) { - lockdep_assert_held(blkg->q->queue_lock); - WARN_ON_ONCE(blkg->refcnt <= 0); - if (!--blkg->refcnt) + WARN_ON_ONCE(atomic_read(&blkg->refcnt) <= 0); + if (atomic_dec_and_test(&blkg->refcnt)) call_rcu(&blkg->rcu_head, __blkg_release_rcu); } |