diff options
| author | Alex Shi <alex.shi@linaro.org> | 2014-07-10 14:12:42 +0800 |
|---|---|---|
| committer | Alex Shi <alex.shi@linaro.org> | 2014-07-10 14:12:42 +0800 |
| commit | 8e887160e24f2d31ed208074170b487e99867a70 (patch) | |
| tree | c72134917218086b28006f35f916362dce7b9de2 /block | |
| parent | 76293380920d7ec221620603e07082eebedb99f4 (diff) | |
| parent | d8e045867020ad8d258b1c21ae86930f5449bfd3 (diff) | |
Merge branch 'linux-linaro-lsk-v3.14' into linux-linaro-lsk-v3.14-android
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-cgroup.c | 7 | ||||
| -rw-r--r-- | block/blk-cgroup.h | 17 |
2 files changed, 9 insertions, 15 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 4e491d9b5292..dd0dd2d4ceca 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -80,7 +80,7 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct request_queue *q, blkg->q = q; INIT_LIST_HEAD(&blkg->q_node); blkg->blkcg = blkcg; - blkg->refcnt = 1; + atomic_set(&blkg->refcnt, 1); /* root blkg uses @q->root_rl, init rl only for !root blkgs */ if (blkcg != &blkcg_root) { @@ -399,11 +399,8 @@ void __blkg_release_rcu(struct rcu_head *rcu_head) /* release the blkcg and parent blkg refs this blkg has been holding */ css_put(&blkg->blkcg->css); - if (blkg->parent) { - spin_lock_irq(blkg->q->queue_lock); + if (blkg->parent) blkg_put(blkg->parent); - spin_unlock_irq(blkg->q->queue_lock); - } blkg_free(blkg); } diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index 86154eab9523..c135f5660702 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; @@ -253,13 +254,12 @@ 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); @@ -267,14 +267,11 @@ 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); } |