diff options
Diffstat (limited to 'block/cfq-iosched.c')
| -rw-r--r-- | block/cfq-iosched.c | 105 |
1 files changed, 53 insertions, 52 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 37e2da9cbb0..1c3f41b9d5d 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -229,7 +229,7 @@ struct cfq_data { struct request_queue *queue; /* Root service tree for cfq_groups */ struct cfq_rb_root grp_service_tree; - struct cfq_group root_group; + struct cfq_group *root_group; /* * The priority currently being served @@ -1012,6 +1012,25 @@ static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg, cfq_blkiocg_set_start_empty_time(&cfqg->blkg); } +/** + * cfq_init_cfqg_base - initialize base part of a cfq_group + * @cfqg: cfq_group to initialize + * + * Initialize the base part which is used whether %CONFIG_CFQ_GROUP_IOSCHED + * is enabled or not. + */ +static void cfq_init_cfqg_base(struct cfq_group *cfqg) +{ + struct cfq_rb_root *st; + int i, j; + + for_each_cfqg_st(cfqg, i, j, st) + *st = CFQ_RB_ROOT; + RB_CLEAR_NODE(&cfqg->rb_node); + + cfqg->ttime.last_end_request = jiffies; +} + #ifdef CONFIG_CFQ_GROUP_IOSCHED static inline struct cfq_group *cfqg_of_blkg(struct blkio_group *blkg) { @@ -1063,19 +1082,14 @@ static void cfq_init_add_cfqg_lists(struct cfq_data *cfqd, */ static struct cfq_group * cfq_alloc_cfqg(struct cfq_data *cfqd) { - struct cfq_group *cfqg = NULL; - int i, j, ret; - struct cfq_rb_root *st; + struct cfq_group *cfqg; + int ret; cfqg = kzalloc_node(sizeof(*cfqg), GFP_ATOMIC, cfqd->queue->node); if (!cfqg) return NULL; - for_each_cfqg_st(cfqg, i, j, st) - *st = CFQ_RB_ROOT; - RB_CLEAR_NODE(&cfqg->rb_node); - - cfqg->ttime.last_end_request = jiffies; + cfq_init_cfqg_base(cfqg); /* * Take the initial reference that will be released on destroy @@ -1106,7 +1120,7 @@ cfq_find_cfqg(struct cfq_data *cfqd, struct blkio_cgroup *blkcg) * Avoid lookup in this case */ if (blkcg == &blkio_root_cgroup) - cfqg = &cfqd->root_group; + cfqg = cfqd->root_group; else cfqg = cfqg_of_blkg(blkiocg_lookup_group(blkcg, cfqd->queue, BLKIO_POLICY_PROP)); @@ -1166,7 +1180,7 @@ static struct cfq_group *cfq_get_cfqg(struct cfq_data *cfqd, } if (!cfqg) - cfqg = &cfqd->root_group; + cfqg = cfqd->root_group; cfq_init_add_cfqg_lists(cfqd, cfqg, blkcg); return cfqg; @@ -1182,7 +1196,7 @@ static void cfq_link_cfqq_cfqg(struct cfq_queue *cfqq, struct cfq_group *cfqg) { /* Currently, all async queues are mapped to root group */ if (!cfq_cfqq_sync(cfqq)) - cfqg = &cfqq->cfqd->root_group; + cfqg = cfqq->cfqd->root_group; cfqq->cfqg = cfqg; /* cfqq reference on cfqg */ @@ -1283,7 +1297,7 @@ static bool cfq_clear_queue(struct request_queue *q) static struct cfq_group *cfq_get_cfqg(struct cfq_data *cfqd, struct blkio_cgroup *blkcg) { - return &cfqd->root_group; + return cfqd->root_group; } static inline struct cfq_group *cfq_ref_get_cfqg(struct cfq_group *cfqg) @@ -3671,9 +3685,8 @@ static void cfq_exit_queue(struct elevator_queue *e) if (wait) synchronize_rcu(); -#ifdef CONFIG_CFQ_GROUP_IOSCHED - /* Free up per cpu stats for root group */ - free_percpu(cfqd->root_group.blkg.stats_cpu); +#ifndef CONFIG_CFQ_GROUP_IOSCHED + kfree(cfqd->root_group); #endif kfree(cfqd); } @@ -3681,52 +3694,40 @@ static void cfq_exit_queue(struct elevator_queue *e) static int cfq_init_queue(struct request_queue *q) { struct cfq_data *cfqd; - int i, j; - struct cfq_group *cfqg; - struct cfq_rb_root *st; + int i; cfqd = kmalloc_node(sizeof(*cfqd), GFP_KERNEL | __GFP_ZERO, q->node); if (!cfqd) return -ENOMEM; + cfqd->queue = q; + q->elevator->elevator_data = cfqd; + /* Init root service tree */ cfqd->grp_service_tree = CFQ_RB_ROOT; - /* Init root group */ - cfqg = &cfqd->root_group; - for_each_cfqg_st(cfqg, i, j, st) - *st = CFQ_RB_ROOT; - RB_CLEAR_NODE(&cfqg->rb_node); - - /* Give preference to root group over other groups */ - cfqg->weight = 2*BLKIO_WEIGHT_DEFAULT; - + /* Init root group and prefer root group over other groups by default */ #ifdef CONFIG_CFQ_GROUP_IOSCHED - /* - * Set root group reference to 2. One reference will be dropped when - * all groups on cfqd->cfqg_list are being deleted during queue exit. - * Other reference will remain there as we don't want to delete this - * group as it is statically allocated and gets destroyed when - * throtl_data goes away. - */ - cfqg->ref = 2; + rcu_read_lock(); + spin_lock_irq(q->queue_lock); - if (blkio_alloc_blkg_stats(&cfqg->blkg)) { - kfree(cfqg); + cfqd->root_group = cfq_get_cfqg(cfqd, &blkio_root_cgroup); + + spin_unlock_irq(q->queue_lock); + rcu_read_unlock(); +#else + cfqd->root_group = kzalloc_node(sizeof(*cfqd->root_group), + GFP_KERNEL, cfqd->queue->node); + if (cfqd->root_group) + cfq_init_cfqg_base(cfqd->root_group); +#endif + if (!cfqd->root_group) { kfree(cfqd); return -ENOMEM; } - rcu_read_lock(); + cfqd->root_group->weight = 2*BLKIO_WEIGHT_DEFAULT; - cfq_blkiocg_add_blkio_group(&blkio_root_cgroup, &cfqg->blkg, - cfqd->queue, 0); - rcu_read_unlock(); - cfqd->nr_blkcg_linked_grps++; - - /* Add group on cfqd->cfqg_list */ - hlist_add_head(&cfqg->cfqd_node, &cfqd->cfqg_list); -#endif /* * Not strictly needed (since RB_ROOT just clears the node and we * zeroed cfqd on alloc), but better be safe in case someone decides @@ -3738,14 +3739,14 @@ static int cfq_init_queue(struct request_queue *q) /* * Our fallback cfqq if cfq_find_alloc_queue() runs into OOM issues. * Grab a permanent reference to it, so that the normal code flow - * will not attempt to free it. + * will not attempt to free it. oom_cfqq is linked to root_group + * but shouldn't hold a reference as it'll never be unlinked. Lose + * the reference from linking right away. */ cfq_init_cfqq(cfqd, &cfqd->oom_cfqq, 1, 0); cfqd->oom_cfqq.ref++; - cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, &cfqd->root_group); - - cfqd->queue = q; - q->elevator->elevator_data = cfqd; + cfq_link_cfqq_cfqg(&cfqd->oom_cfqq, cfqd->root_group); + cfq_put_cfqg(cfqd->root_group); init_timer(&cfqd->idle_slice_timer); cfqd->idle_slice_timer.function = cfq_idle_slice_timer; |