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Diffstat (limited to 'block/blk-cgroup.c')
-rw-r--r--block/blk-cgroup.c24
1 files changed, 9 insertions, 15 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index e9e3b038c70..27d39a810cb 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -500,7 +500,7 @@ static struct blkio_group *blkg_alloc(struct blkio_cgroup *blkcg,
return NULL;
spin_lock_init(&blkg->stats_lock);
- rcu_assign_pointer(blkg->q, q);
+ blkg->q = q;
INIT_LIST_HEAD(&blkg->q_node);
blkg->blkcg = blkcg;
blkg->refcnt = 1;
@@ -611,7 +611,6 @@ struct blkio_group *blkg_lookup_create(struct blkio_cgroup *blkcg,
hlist_add_head_rcu(&blkg->blkcg_node, &blkcg->blkg_list);
list_add(&blkg->q_node, &q->blkg_list);
- q->nr_blkgs++;
spin_unlock(&blkcg->lock);
out:
@@ -648,9 +647,6 @@ static void blkg_destroy(struct blkio_group *blkg)
list_del_init(&blkg->q_node);
hlist_del_init_rcu(&blkg->blkcg_node);
- WARN_ON_ONCE(q->nr_blkgs <= 0);
- q->nr_blkgs--;
-
/*
* Put the reference taken at the time of creation so that when all
* queues are gone, group can be destroyed.
@@ -1232,8 +1228,9 @@ static int blkio_read_blkg_stats(struct blkio_cgroup *blkcg,
struct hlist_node *n;
uint64_t cgroup_total = 0;
- rcu_read_lock();
- hlist_for_each_entry_rcu(blkg, n, &blkcg->blkg_list, blkcg_node) {
+ spin_lock_irq(&blkcg->lock);
+
+ hlist_for_each_entry(blkg, n, &blkcg->blkg_list, blkcg_node) {
const char *dname = blkg_dev_name(blkg);
int plid = BLKIOFILE_POLICY(cft->private);
@@ -1243,15 +1240,16 @@ static int blkio_read_blkg_stats(struct blkio_cgroup *blkcg,
cgroup_total += blkio_get_stat_cpu(blkg, plid,
cb, dname, type);
} else {
- spin_lock_irq(&blkg->stats_lock);
+ spin_lock(&blkg->stats_lock);
cgroup_total += blkio_get_stat(blkg, plid,
cb, dname, type);
- spin_unlock_irq(&blkg->stats_lock);
+ spin_unlock(&blkg->stats_lock);
}
}
if (show_total)
cb->fill(cb, "Total", cgroup_total);
- rcu_read_unlock();
+
+ spin_unlock_irq(&blkcg->lock);
return 0;
}
@@ -1583,28 +1581,24 @@ static int blkiocg_pre_destroy(struct cgroup_subsys *subsys,
{
struct blkio_cgroup *blkcg = cgroup_to_blkio_cgroup(cgroup);
- rcu_read_lock();
spin_lock_irq(&blkcg->lock);
while (!hlist_empty(&blkcg->blkg_list)) {
struct blkio_group *blkg = hlist_entry(blkcg->blkg_list.first,
struct blkio_group, blkcg_node);
- struct request_queue *q = rcu_dereference(blkg->q);
+ struct request_queue *q = blkg->q;
if (spin_trylock(q->queue_lock)) {
blkg_destroy(blkg);
spin_unlock(q->queue_lock);
} else {
spin_unlock_irq(&blkcg->lock);
- rcu_read_unlock();
cpu_relax();
- rcu_read_lock();
spin_lock(&blkcg->lock);
}
}
spin_unlock_irq(&blkcg->lock);
- rcu_read_unlock();
return 0;
}