diff options
| -rw-r--r-- | block/blk-cgroup.c | 84 |
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) |