X-Git-Url: https://git.stricted.de/?a=blobdiff_plain;f=block%2Fblk-cgroup.c;h=f3b44a65fc7ad5f127bee8bcbadf5b486a7e5c71;hb=79df9b40b3d0fd275b4d6eae6068706871e95da5;hp=e7dee617358e810aec57ff25162ff95604fabb3c;hpb=d5d96ed2d89ea228bdc27980b8ee4c94422ddef5;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index e7dee617358e..f3b44a65fc7a 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -31,27 +31,6 @@ EXPORT_SYMBOL_GPL(blkcg_root); static struct blkcg_policy *blkcg_policy[BLKCG_MAX_POLS]; -struct blkcg *cgroup_to_blkcg(struct cgroup *cgroup) -{ - return container_of(cgroup_subsys_state(cgroup, blkio_subsys_id), - struct blkcg, css); -} -EXPORT_SYMBOL_GPL(cgroup_to_blkcg); - -static struct blkcg *task_blkcg(struct task_struct *tsk) -{ - return container_of(task_subsys_state(tsk, blkio_subsys_id), - struct blkcg, css); -} - -struct blkcg *bio_blkcg(struct bio *bio) -{ - if (bio && bio->bi_css) - return container_of(bio->bi_css, struct blkcg, css); - return task_blkcg(current); -} -EXPORT_SYMBOL_GPL(bio_blkcg); - static bool blkcg_policy_enabled(struct request_queue *q, const struct blkcg_policy *pol) { @@ -84,6 +63,7 @@ static void blkg_free(struct blkcg_gq *blkg) kfree(pd); } + blk_exit_rl(&blkg->rl); kfree(blkg); } @@ -91,16 +71,18 @@ static void blkg_free(struct blkcg_gq *blkg) * blkg_alloc - allocate a blkg * @blkcg: block cgroup the new blkg is associated with * @q: request_queue the new blkg is associated with + * @gfp_mask: allocation mask to use * * Allocate a new blkg assocating @blkcg and @q. */ -static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct request_queue *q) +static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct request_queue *q, + gfp_t gfp_mask) { struct blkcg_gq *blkg; int i; /* alloc and init base part */ - blkg = kzalloc_node(sizeof(*blkg), GFP_ATOMIC, q->node); + blkg = kzalloc_node(sizeof(*blkg), gfp_mask, q->node); if (!blkg) return NULL; @@ -109,6 +91,13 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct request_queue *q) blkg->blkcg = blkcg; blkg->refcnt = 1; + /* root blkg uses @q->root_rl, init rl only for !root blkgs */ + if (blkcg != &blkcg_root) { + if (blk_init_rl(&blkg->rl, q, gfp_mask)) + goto err_free; + blkg->rl.blkg = blkg; + } + for (i = 0; i < BLKCG_MAX_POLS; i++) { struct blkcg_policy *pol = blkcg_policy[i]; struct blkg_policy_data *pd; @@ -117,11 +106,9 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct request_queue *q) continue; /* alloc per-policy data and attach it to blkg */ - pd = kzalloc_node(pol->pd_size, GFP_ATOMIC, q->node); - if (!pd) { - blkg_free(blkg); - return NULL; - } + pd = kzalloc_node(pol->pd_size, gfp_mask, q->node); + if (!pd) + goto err_free; blkg->pd[i] = pd; pd->blkg = blkg; @@ -132,6 +119,10 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct request_queue *q) } return blkg; + +err_free: + blkg_free(blkg); + return NULL; } static struct blkcg_gq *__blkg_lookup(struct blkcg *blkcg, @@ -175,9 +166,13 @@ struct blkcg_gq *blkg_lookup(struct blkcg *blkcg, struct request_queue *q) } EXPORT_SYMBOL_GPL(blkg_lookup); +/* + * If @new_blkg is %NULL, this function tries to allocate a new one as + * necessary using %GFP_ATOMIC. @new_blkg is always consumed on return. + */ static struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg, - struct request_queue *q) - __releases(q->queue_lock) __acquires(q->queue_lock) + struct request_queue *q, + struct blkcg_gq *new_blkg) { struct blkcg_gq *blkg; int ret; @@ -189,24 +184,26 @@ static struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg, blkg = __blkg_lookup(blkcg, q); if (blkg) { rcu_assign_pointer(blkcg->blkg_hint, blkg); - return blkg; + goto out_free; } /* blkg holds a reference to blkcg */ - if (!css_tryget(&blkcg->css)) - return ERR_PTR(-EINVAL); + if (!css_tryget(&blkcg->css)) { + blkg = ERR_PTR(-EINVAL); + goto out_free; + } /* allocate */ - ret = -ENOMEM; - blkg = blkg_alloc(blkcg, q); - if (unlikely(!blkg)) - goto err_put; + if (!new_blkg) { + new_blkg = blkg_alloc(blkcg, q, GFP_ATOMIC); + if (unlikely(!new_blkg)) { + blkg = ERR_PTR(-ENOMEM); + goto out_put; + } + } + blkg = new_blkg; /* insert */ - ret = radix_tree_preload(GFP_ATOMIC); - if (ret) - goto err_free; - spin_lock(&blkcg->lock); ret = radix_tree_insert(&blkcg->blkg_tree, q->id, blkg); if (likely(!ret)) { @@ -215,15 +212,15 @@ static struct blkcg_gq *__blkg_lookup_create(struct blkcg *blkcg, } spin_unlock(&blkcg->lock); - radix_tree_preload_end(); - if (!ret) return blkg; -err_free: - blkg_free(blkg); -err_put: + + blkg = ERR_PTR(ret); +out_put: css_put(&blkcg->css); - return ERR_PTR(ret); +out_free: + blkg_free(new_blkg); + return blkg; } struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg, @@ -235,7 +232,7 @@ struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg, */ if (unlikely(blk_queue_bypass(q))) return ERR_PTR(blk_queue_dead(q) ? -EINVAL : -EBUSY); - return __blkg_lookup_create(blkcg, q); + return __blkg_lookup_create(blkcg, q, NULL); } EXPORT_SYMBOL_GPL(blkg_lookup_create); @@ -313,6 +310,38 @@ void __blkg_release(struct blkcg_gq *blkg) } EXPORT_SYMBOL_GPL(__blkg_release); +/* + * The next function used by blk_queue_for_each_rl(). It's a bit tricky + * because the root blkg uses @q->root_rl instead of its own rl. + */ +struct request_list *__blk_queue_next_rl(struct request_list *rl, + struct request_queue *q) +{ + struct list_head *ent; + struct blkcg_gq *blkg; + + /* + * Determine the current blkg list_head. The first entry is + * root_rl which is off @q->blkg_list and mapped to the head. + */ + if (rl == &q->root_rl) { + ent = &q->blkg_list; + } else { + blkg = container_of(rl, struct blkcg_gq, rl); + ent = &blkg->q_node; + } + + /* walk to the next list_head, skip root blkcg */ + ent = ent->next; + if (ent == &q->root_blkg->q_node) + ent = ent->next; + if (ent == &q->blkg_list) + return NULL; + + blkg = container_of(ent, struct blkcg_gq, q_node); + return &blkg->rl; +} + static int blkcg_reset_stats(struct cgroup *cgroup, struct cftype *cftype, u64 val) { @@ -734,24 +763,36 @@ int blkcg_activate_policy(struct request_queue *q, struct blkcg_gq *blkg; struct blkg_policy_data *pd, *n; int cnt = 0, ret; + bool preloaded; if (blkcg_policy_enabled(q, pol)) return 0; + /* preallocations for root blkg */ + blkg = blkg_alloc(&blkcg_root, q, GFP_KERNEL); + if (!blkg) + return -ENOMEM; + + preloaded = !radix_tree_preload(GFP_KERNEL); + blk_queue_bypass_start(q); /* make sure the root blkg exists and count the existing blkgs */ spin_lock_irq(q->queue_lock); rcu_read_lock(); - blkg = __blkg_lookup_create(&blkcg_root, q); + blkg = __blkg_lookup_create(&blkcg_root, q, blkg); rcu_read_unlock(); + if (preloaded) + radix_tree_preload_end(); + if (IS_ERR(blkg)) { ret = PTR_ERR(blkg); goto out_unlock; } q->root_blkg = blkg; + q->root_rl.blkg = blkg; list_for_each_entry(blkg, &q->blkg_list, q_node) cnt++;