From 3c96cb32d318f323c1bf972a4c66821f8499e34d Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 13 Apr 2012 13:11:34 -0700 Subject: blkcg: drop stuff unused after per-queue policy activation update * All_q_list is unused. Drop all_q_{mutex|list}. * @for_root of blkg_lookup_create() is always %false when called from outside blk-cgroup.c proper. Factor out __blkg_lookup_create() so that it doesn't check whether @q is bypassing and use the underscored version for the @for_root callsite. * blkg_destroy_all() is used only from blkcg proper and @destroy_root is always %true. Make it static and drop @destroy_root. Signed-off-by: Tejun Heo Cc: Vivek Goyal Signed-off-by: Jens Axboe --- block/blk-cgroup.c | 61 ++++++++++++++++++------------------------------------ 1 file changed, 20 insertions(+), 41 deletions(-) (limited to 'block/blk-cgroup.c') diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index d6d59ad105b..10f0d2fc0b2 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -25,8 +25,6 @@ #define MAX_KEY_LEN 100 static DEFINE_MUTEX(blkcg_pol_mutex); -static DEFINE_MUTEX(all_q_mutex); -static LIST_HEAD(all_q_list); struct blkio_cgroup blkio_root_cgroup = { .cfq_weight = 2 * CFQ_WEIGHT_DEFAULT }; EXPORT_SYMBOL_GPL(blkio_root_cgroup); @@ -179,9 +177,8 @@ struct blkio_group *blkg_lookup(struct blkio_cgroup *blkcg, } EXPORT_SYMBOL_GPL(blkg_lookup); -struct blkio_group *blkg_lookup_create(struct blkio_cgroup *blkcg, - struct request_queue *q, - bool for_root) +static struct blkio_group *__blkg_lookup_create(struct blkio_cgroup *blkcg, + struct request_queue *q) __releases(q->queue_lock) __acquires(q->queue_lock) { struct blkio_group *blkg; @@ -189,13 +186,6 @@ struct blkio_group *blkg_lookup_create(struct blkio_cgroup *blkcg, WARN_ON_ONCE(!rcu_read_lock_held()); lockdep_assert_held(q->queue_lock); - /* - * This could be the first entry point of blkcg implementation and - * we shouldn't allow anything to go through for a bypassing queue. - */ - if (unlikely(blk_queue_bypass(q)) && !for_root) - return ERR_PTR(blk_queue_dead(q) ? -EINVAL : -EBUSY); - blkg = __blkg_lookup(blkcg, q); if (blkg) return blkg; @@ -223,6 +213,18 @@ struct blkio_group *blkg_lookup_create(struct blkio_cgroup *blkcg, out: return blkg; } + +struct blkio_group *blkg_lookup_create(struct blkio_cgroup *blkcg, + struct request_queue *q) +{ + /* + * This could be the first entry point of blkcg implementation and + * we shouldn't allow anything to go through for a bypassing queue. + */ + if (unlikely(blk_queue_bypass(q))) + return ERR_PTR(blk_queue_dead(q) ? -EINVAL : -EBUSY); + return __blkg_lookup_create(blkcg, q); +} EXPORT_SYMBOL_GPL(blkg_lookup_create); static void blkg_destroy(struct blkio_group *blkg) @@ -249,12 +251,10 @@ static void blkg_destroy(struct blkio_group *blkg) /** * blkg_destroy_all - destroy all blkgs associated with a request_queue * @q: request_queue of interest - * @destroy_root: whether to destroy root blkg or not * - * Destroy blkgs associated with @q. If @destroy_root is %true, all are - * destroyed; otherwise, root blkg is left alone. + * Destroy all blkgs associated with @q. */ -void blkg_destroy_all(struct request_queue *q, bool destroy_root) +static void blkg_destroy_all(struct request_queue *q) { struct blkio_group *blkg, *n; @@ -263,10 +263,6 @@ void blkg_destroy_all(struct request_queue *q, bool destroy_root) list_for_each_entry_safe(blkg, n, &q->blkg_list, q_node) { struct blkio_cgroup *blkcg = blkg->blkcg; - /* skip root? */ - if (!destroy_root && blkg->blkcg == &blkio_root_cgroup) - continue; - spin_lock(&blkcg->lock); blkg_destroy(blkg); spin_unlock(&blkcg->lock); @@ -274,7 +270,6 @@ void blkg_destroy_all(struct request_queue *q, bool destroy_root) spin_unlock_irq(q->queue_lock); } -EXPORT_SYMBOL_GPL(blkg_destroy_all); static void blkg_rcu_free(struct rcu_head *rcu_head) { @@ -492,7 +487,7 @@ int blkg_conf_prep(struct blkio_cgroup *blkcg, spin_lock_irq(disk->queue->queue_lock); if (blkcg_policy_enabled(disk->queue, pol)) - blkg = blkg_lookup_create(blkcg, disk->queue, false); + blkg = blkg_lookup_create(blkcg, disk->queue); else blkg = ERR_PTR(-EINVAL); @@ -625,20 +620,9 @@ done: */ int blkcg_init_queue(struct request_queue *q) { - int ret; - might_sleep(); - ret = blk_throtl_init(q); - if (ret) - return ret; - - mutex_lock(&all_q_mutex); - INIT_LIST_HEAD(&q->all_q_node); - list_add_tail(&q->all_q_node, &all_q_list); - mutex_unlock(&all_q_mutex); - - return 0; + return blk_throtl_init(q); } /** @@ -662,12 +646,7 @@ void blkcg_drain_queue(struct request_queue *q) */ void blkcg_exit_queue(struct request_queue *q) { - mutex_lock(&all_q_mutex); - list_del_init(&q->all_q_node); - mutex_unlock(&all_q_mutex); - - blkg_destroy_all(q, true); - + blkg_destroy_all(q); blk_throtl_exit(q); } @@ -741,7 +720,7 @@ int blkcg_activate_policy(struct request_queue *q, spin_lock_irq(q->queue_lock); rcu_read_lock(); - blkg = blkg_lookup_create(&blkio_root_cgroup, q, true); + blkg = __blkg_lookup_create(&blkio_root_cgroup, q); rcu_read_unlock(); if (IS_ERR(blkg)) { -- cgit v1.2.3