1 files changed, 40 insertions, 44 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index d02bbf88de13..60bb049b6106 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -376,17 +376,16 @@ int blkiocg_del_blkio_group(struct blkio_group *blkg)
 
         rcu_read_lock();
         css = css_lookup(&blkio_subsys, blkg->blkcg_id);
-        if (!css)
-                goto out;
-
-        blkcg = container_of(css, struct blkio_cgroup, css);
-        spin_lock_irqsave(&blkcg->lock, flags);
-        if (!hlist_unhashed(&blkg->blkcg_node)) {
-                __blkiocg_del_blkio_group(blkg);
-                ret = 0;
+        if (css) {
+                blkcg = container_of(css, struct blkio_cgroup, css);
+                spin_lock_irqsave(&blkcg->lock, flags);
+                if (!hlist_unhashed(&blkg->blkcg_node)) {
+                        __blkiocg_del_blkio_group(blkg);
+                        ret = 0;
+                }
+                spin_unlock_irqrestore(&blkcg->lock, flags);
         }
-        spin_unlock_irqrestore(&blkcg->lock, flags);
-out:
+
         rcu_read_unlock();
         return ret;
 }
@@ -815,17 +814,15 @@ static int blkiocg_weight_device_read(struct cgroup *cgrp, struct cftype *cft,
         seq_printf(m, "dev\tweight\n");
 
         blkcg = cgroup_to_blkio_cgroup(cgrp);
-        if (list_empty(&blkcg->policy_list))
-                goto out;
-
-        spin_lock_irq(&blkcg->lock);
-        list_for_each_entry(pn, &blkcg->policy_list, node) {
-                seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev),
-                           MINOR(pn->dev), pn->weight);
+        if (!list_empty(&blkcg->policy_list)) {
+                spin_lock_irq(&blkcg->lock);
+                list_for_each_entry(pn, &blkcg->policy_list, node) {
+                        seq_printf(m, "%u:%u\t%u\n", MAJOR(pn->dev),
+                                   MINOR(pn->dev), pn->weight);
+                }
+                spin_unlock_irq(&blkcg->lock);
         }
-        spin_unlock_irq(&blkcg->lock);
 
-out:
         return 0;
 }
 
@@ -917,40 +914,39 @@ static void blkiocg_destroy(struct cgroup_subsys *subsys, struct cgroup *cgroup)
         struct blkio_policy_node *pn, *pntmp;
 
         rcu_read_lock();
-remove_entry:
-        spin_lock_irqsave(&blkcg->lock, flags);
+        do {
+                spin_lock_irqsave(&blkcg->lock, flags);
 
-        if (hlist_empty(&blkcg->blkg_list)) {
-                spin_unlock_irqrestore(&blkcg->lock, flags);
-                goto done;
-        }
+                if (hlist_empty(&blkcg->blkg_list)) {
+                        spin_unlock_irqrestore(&blkcg->lock, flags);
+                        break;
+                }
 
-        blkg = hlist_entry(blkcg->blkg_list.first, struct blkio_group,
-                                blkcg_node);
-        key = rcu_dereference(blkg->key);
-        __blkiocg_del_blkio_group(blkg);
+                blkg = hlist_entry(blkcg->blkg_list.first, struct blkio_group,
+                                        blkcg_node);
+                key = rcu_dereference(blkg->key);
+                __blkiocg_del_blkio_group(blkg);
 
-        spin_unlock_irqrestore(&blkcg->lock, flags);
+                spin_unlock_irqrestore(&blkcg->lock, flags);
 
-        /*
-         * This blkio_group is being unlinked as associated cgroup is going
-         * away. Let all the IO controlling policies know about this event.
-         *
-         * Currently this is static call to one io controlling policy. Once
-         * we have more policies in place, we need some dynamic registration
-         * of callback function.
-         */
-        spin_lock(&blkio_list_lock);
-        list_for_each_entry(blkiop, &blkio_list, list)
-                blkiop->ops.blkio_unlink_group_fn(key, blkg);
-        spin_unlock(&blkio_list_lock);
-        goto remove_entry;
+                /*
+                 * This blkio_group is being unlinked as associated cgroup is
+                 * going away. Let all the IO controlling policies know about
+                 * this event. Currently this is static call to one io
+                 * controlling policy. Once we have more policies in place, we
+                 * need some dynamic registration of callback function.
+                 */
+                spin_lock(&blkio_list_lock);
+                list_for_each_entry(blkiop, &blkio_list, list)
+                        blkiop->ops.blkio_unlink_group_fn(key, blkg);
+                spin_unlock(&blkio_list_lock);
+        } while (1);
 
-done:
         list_for_each_entry_safe(pn, pntmp, &blkcg->policy_list, node) {
                 blkio_policy_delete_node(pn);
                 kfree(pn);
         }
+
         free_css_id(&blkio_subsys, &blkcg->css);
         rcu_read_unlock();
         if (blkcg != &blkio_root_cgroup)