diff options
| author | Tejun Heo <tj@kernel.org> | 2013-01-09 08:05:13 -0800 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2013-01-09 08:05:13 -0800 |
| commit | 548bc8e1b38e48653a90f48f636f8d253504f8a2 (patch) | |
| tree | db4aca3e40185423e465ef5a67f44658ff292443 | |
| parent | 16b3de6652c7aef151f38726faf90f0dbc9e9c71 (diff) | |
block: RCU free request_queue
RCU free request_queue so that blkcg_gq->q can be dereferenced under
RCU lock. This will be used to implement hierarchical stats.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
| -rw-r--r-- | block/blk-sysfs.c | 9 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 2 |
2 files changed, 10 insertions, 1 deletions
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 788147797a7..6206a934eb8 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -497,6 +497,13 @@ queue_attr_store(struct kobject *kobj, struct attribute *attr, return res; } +static void blk_free_queue_rcu(struct rcu_head *rcu_head) +{ + struct request_queue *q = container_of(rcu_head, struct request_queue, + rcu_head); + kmem_cache_free(blk_requestq_cachep, q); +} + /** * blk_release_queue: - release a &struct request_queue when it is no longer needed * @kobj: the kobj belonging to the request queue to be released @@ -538,7 +545,7 @@ static void blk_release_queue(struct kobject *kobj) bdi_destroy(&q->backing_dev_info); ida_simple_remove(&blk_queue_ida, q->id); - kmem_cache_free(blk_requestq_cachep, q); + call_rcu(&q->rcu_head, blk_free_queue_rcu); } static const struct sysfs_ops queue_sysfs_ops = { diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index f94bc83011e..406343c43cd 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -19,6 +19,7 @@ #include <linux/gfp.h> #include <linux/bsg.h> #include <linux/smp.h> +#include <linux/rcupdate.h> #include <asm/scatterlist.h> @@ -437,6 +438,7 @@ struct request_queue { /* Throttle data */ struct throtl_data *td; #endif + struct rcu_head rcu_head; }; #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ |