diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-cgroup.c | 24 | ||||
| -rw-r--r-- | block/blk-cgroup.h | 4 | ||||
| -rw-r--r-- | block/blk-throttle.c | 33 | ||||
| -rw-r--r-- | block/cfq-iosched.c | 24 |
4 files changed, 12 insertions, 73 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index e9e3b038c702..27d39a810cb6 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; } diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index df73040a6a5f..66eaefefcbd2 100644 --- a/block/blk-cgroup.h +++ b/block/blk-cgroup.h @@ -176,8 +176,8 @@ struct blkg_policy_data { }; struct blkio_group { - /* Pointer to the associated request_queue, RCU protected */ - struct request_queue __rcu *q; + /* Pointer to the associated request_queue */ + struct request_queue *q; struct list_head q_node; struct hlist_node blkcg_node; struct blkio_cgroup *blkcg; diff --git a/block/blk-throttle.c b/block/blk-throttle.c index e35ee7aeea69..bfa5168249eb 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -1046,39 +1046,8 @@ int blk_throtl_init(struct request_queue *q) void blk_throtl_exit(struct request_queue *q) { - struct throtl_data *td = q->td; - bool wait; - - BUG_ON(!td); - + BUG_ON(!q->td); throtl_shutdown_wq(q); - - /* If there are other groups */ - spin_lock_irq(q->queue_lock); - wait = q->nr_blkgs; - spin_unlock_irq(q->queue_lock); - - /* - * Wait for tg_to_blkg(tg)->q accessors to exit their grace periods. - * Do this wait only if there are other undestroyed groups out - * there (other than root group). This can happen if cgroup deletion - * path claimed the responsibility of cleaning up a group before - * queue cleanup code get to the group. - * - * Do not call synchronize_rcu() unconditionally as there are drivers - * which create/delete request queue hundreds of times during scan/boot - * and synchronize_rcu() can take significant time and slow down boot. - */ - if (wait) - synchronize_rcu(); - - /* - * Just being safe to make sure after previous flush if some body did - * update limits through cgroup and another work got queued, cancel - * it. - */ - throtl_shutdown_wq(q); - kfree(q->td); } diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 393eaa59913b..9e386d9bcb79 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -3449,7 +3449,6 @@ static void cfq_exit_queue(struct elevator_queue *e) { struct cfq_data *cfqd = e->elevator_data; struct request_queue *q = cfqd->queue; - bool wait = false; cfq_shutdown_timer_wq(cfqd); @@ -3462,31 +3461,8 @@ static void cfq_exit_queue(struct elevator_queue *e) spin_unlock_irq(q->queue_lock); -#ifdef CONFIG_BLK_CGROUP - /* - * If there are groups which we could not unlink from blkcg list, - * wait for a rcu period for them to be freed. - */ - spin_lock_irq(q->queue_lock); - wait = q->nr_blkgs; - spin_unlock_irq(q->queue_lock); -#endif cfq_shutdown_timer_wq(cfqd); - /* - * Wait for cfqg->blkg->key accessors to exit their grace periods. - * Do this wait only if there are other unlinked groups out - * there. This can happen if cgroup deletion path claimed the - * responsibility of cleaning up a group before queue cleanup code - * get to the group. - * - * Do not call synchronize_rcu() unconditionally as there are drivers - * which create/delete request queue hundreds of times during scan/boot - * and synchronize_rcu() can take significant time and slow down boot. - */ - if (wait) - synchronize_rcu(); - #ifndef CONFIG_CFQ_GROUP_IOSCHED kfree(cfqd->root_group); #endif |