aboutsummaryrefslogtreecommitdiff
path: root/block
diff options
context:
space:
mode:
authorAlex Shi <alex.shi@linaro.org>2014-07-10 14:12:42 +0800
committerAlex Shi <alex.shi@linaro.org>2014-07-10 14:12:42 +0800
commit8e887160e24f2d31ed208074170b487e99867a70 (patch)
treec72134917218086b28006f35f916362dce7b9de2 /block
parent76293380920d7ec221620603e07082eebedb99f4 (diff)
parentd8e045867020ad8d258b1c21ae86930f5449bfd3 (diff)
downloadlinux-linaro-stable-8e887160e24f2d31ed208074170b487e99867a70.tar.gz
Merge branch 'linux-linaro-lsk-v3.14' into linux-linaro-lsk-v3.14-android
Diffstat (limited to 'block')
-rw-r--r--block/blk-cgroup.c7
-rw-r--r--block/blk-cgroup.h17
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);
}