diff options
Diffstat (limited to 'block/blk-cgroup.c')
| -rw-r--r-- | block/blk-cgroup.c | 91 |
1 files changed, 81 insertions, 10 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 31610ae0ebff..9f97da52d006 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -9,6 +9,10 @@ * * Copyright (C) 2009 Vivek Goyal <vgoyal@redhat.com> * Nauman Rafique <nauman@google.com> + * + * For policy-specific per-blkcg data: + * Copyright (C) 2015 Paolo Valente <paolo.valente@unimore.it> + * Arianna Avanzini <avanzini.arianna@gmail.com> */ #include <linux/ioprio.h> #include <linux/kdev_t.h> @@ -27,8 +31,7 @@ static DEFINE_MUTEX(blkcg_pol_mutex); -struct blkcg blkcg_root = { .cfq_weight = 2 * CFQ_WEIGHT_DEFAULT, - .cfq_leaf_weight = 2 * CFQ_WEIGHT_DEFAULT, }; +struct blkcg blkcg_root; EXPORT_SYMBOL_GPL(blkcg_root); struct cgroup_subsys_state * const blkcg_root_css = &blkcg_root.css; @@ -827,6 +830,8 @@ static struct cgroup_subsys_state * blkcg_css_alloc(struct cgroup_subsys_state *parent_css) { struct blkcg *blkcg; + struct cgroup_subsys_state *ret; + int i; if (!parent_css) { blkcg = &blkcg_root; @@ -834,11 +839,35 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css) } blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL); - if (!blkcg) - return ERR_PTR(-ENOMEM); + if (!blkcg) { + ret = ERR_PTR(-ENOMEM); + goto free_blkcg; + } + + for (i = 0; i < BLKCG_MAX_POLS ; i++) { + struct blkcg_policy *pol = blkcg_policy[i]; + struct blkcg_policy_data *cpd; + + /* + * If the policy hasn't been attached yet, wait for it + * to be attached before doing anything else. Otherwise, + * check if the policy requires any specific per-cgroup + * data: if it does, allocate and initialize it. + */ + if (!pol || !pol->cpd_size) + continue; + + BUG_ON(blkcg->pd[i]); + cpd = kzalloc(pol->cpd_size, GFP_KERNEL); + if (!cpd) { + ret = ERR_PTR(-ENOMEM); + goto free_pd_blkcg; + } + blkcg->pd[i] = cpd; + cpd->plid = i; + pol->cpd_init_fn(blkcg); + } - blkcg->cfq_weight = CFQ_WEIGHT_DEFAULT; - blkcg->cfq_leaf_weight = CFQ_WEIGHT_DEFAULT; done: spin_lock_init(&blkcg->lock); INIT_RADIX_TREE(&blkcg->blkg_tree, GFP_ATOMIC); @@ -847,6 +876,14 @@ done: INIT_LIST_HEAD(&blkcg->cgwb_list); #endif return &blkcg->css; + +free_pd_blkcg: + for (i--; i >= 0; i--) + kfree(blkcg->pd[i]); + +free_blkcg: + kfree(blkcg); + return ret; } /** @@ -1000,8 +1037,10 @@ int blkcg_activate_policy(struct request_queue *q, const struct blkcg_policy *pol) { LIST_HEAD(pds); + LIST_HEAD(cpds); struct blkcg_gq *blkg; - struct blkg_policy_data *pd, *n; + struct blkg_policy_data *pd, *nd; + struct blkcg_policy_data *cpd, *cnd; int cnt = 0, ret; if (blkcg_policy_enabled(q, pol)) @@ -1014,6 +1053,10 @@ int blkcg_activate_policy(struct request_queue *q, cnt++; spin_unlock_irq(q->queue_lock); + /* + * Allocate per-blkg and per-blkcg policy data + * for all existing blkgs. + */ while (cnt--) { pd = kzalloc_node(pol->pd_size, GFP_KERNEL, q->node); if (!pd) { @@ -1021,26 +1064,50 @@ int blkcg_activate_policy(struct request_queue *q, goto out_free; } list_add_tail(&pd->alloc_node, &pds); + + if (!pol->cpd_size) + continue; + cpd = kzalloc_node(pol->cpd_size, GFP_KERNEL, q->node); + if (!cpd) { + ret = -ENOMEM; + goto out_free; + } + list_add_tail(&cpd->alloc_node, &cpds); } /* - * Install the allocated pds. With @q bypassing, no new blkg + * Install the allocated pds and cpds. With @q bypassing, no new blkg * should have been created while the queue lock was dropped. */ spin_lock_irq(q->queue_lock); list_for_each_entry(blkg, &q->blkg_list, q_node) { - if (WARN_ON(list_empty(&pds))) { + if (WARN_ON(list_empty(&pds)) || + WARN_ON(pol->cpd_size && list_empty(&cpds))) { /* umm... this shouldn't happen, just abort */ ret = -ENOMEM; goto out_unlock; } + cpd = list_first_entry(&cpds, struct blkcg_policy_data, + alloc_node); + list_del_init(&cpd->alloc_node); pd = list_first_entry(&pds, struct blkg_policy_data, alloc_node); list_del_init(&pd->alloc_node); /* grab blkcg lock too while installing @pd on @blkg */ spin_lock(&blkg->blkcg->lock); + if (!pol->cpd_size) + goto no_cpd; + if (!blkg->blkcg->pd[pol->plid]) { + /* Per-policy per-blkcg data */ + blkg->blkcg->pd[pol->plid] = cpd; + cpd->plid = pol->plid; + pol->cpd_init_fn(blkg->blkcg); + } else { /* must free it as it has already been extracted */ + kfree(cpd); + } +no_cpd: blkg->pd[pol->plid] = pd; pd->blkg = blkg; pd->plid = pol->plid; @@ -1055,8 +1122,10 @@ out_unlock: spin_unlock_irq(q->queue_lock); out_free: blk_queue_bypass_end(q); - list_for_each_entry_safe(pd, n, &pds, alloc_node) + list_for_each_entry_safe(pd, nd, &pds, alloc_node) kfree(pd); + list_for_each_entry_safe(cpd, cnd, &cpds, alloc_node) + kfree(cpd); return ret; } EXPORT_SYMBOL_GPL(blkcg_activate_policy); @@ -1093,6 +1162,8 @@ void blkcg_deactivate_policy(struct request_queue *q, kfree(blkg->pd[pol->plid]); blkg->pd[pol->plid] = NULL; + kfree(blkg->blkcg->pd[pol->plid]); + blkg->blkcg->pd[pol->plid] = NULL; spin_unlock(&blkg->blkcg->lock); } |