From 814376483e7d85b69a70634633f1f9d01c6ee0cf Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 18 Aug 2015 14:55:15 -0700 Subject: [PATCH] blkcg: minor updates around blkcg_policy_data * Rename blkcg->pd[] to blkcg->cpd[] so that cpd is consistently used for blkcg_policy_data. * Make blkcg_policy->cpd_init_fn() take blkcg_policy_data instead of blkcg. This makes it consistent with blkg_policy_data methods and to-be-added cpd alloc/free methods. * blkcg_policy_data->blkcg and cpd_to_blkcg() added so that cpd_init_fn() can determine the associated blkcg from blkcg_policy_data. v2: blkcg_policy_data->blkcg initializations were missing. Added. Signed-off-by: Tejun Heo Cc: Vivek Goyal Cc: Arianna Avanzini Signed-off-by: Jens Axboe --- block/blk-cgroup.c | 24 +++++++++++++----------- block/cfq-iosched.c | 11 +++++------ include/linux/blk-cgroup.h | 14 ++++++++++---- 3 files changed, 28 insertions(+), 21 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 8343450cffe2..247c42c8c83b 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -821,7 +821,7 @@ static void blkcg_css_free(struct cgroup_subsys_state *css) mutex_unlock(&blkcg_pol_mutex); for (i = 0; i < BLKCG_MAX_POLS; i++) - kfree(blkcg->pd[i]); + kfree(blkcg->cpd[i]); kfree(blkcg); } @@ -857,15 +857,16 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css) if (!pol || !pol->cpd_size) continue; - BUG_ON(blkcg->pd[i]); + BUG_ON(blkcg->cpd[i]); cpd = kzalloc(pol->cpd_size, GFP_KERNEL); if (!cpd) { ret = ERR_PTR(-ENOMEM); goto free_pd_blkcg; } - blkcg->pd[i] = cpd; + blkcg->cpd[i] = cpd; + cpd->blkcg = blkcg; cpd->plid = i; - pol->cpd_init_fn(blkcg); + pol->cpd_init_fn(cpd); } spin_lock_init(&blkcg->lock); @@ -881,7 +882,7 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css) free_pd_blkcg: for (i--; i >= 0; i--) - kfree(blkcg->pd[i]); + kfree(blkcg->cpd[i]); free_blkcg: kfree(blkcg); mutex_unlock(&blkcg_pol_mutex); @@ -1168,9 +1169,10 @@ int blkcg_policy_register(struct blkcg_policy *pol) goto err_free_cpds; } - blkcg->pd[pol->plid] = cpd; + blkcg->cpd[pol->plid] = cpd; + cpd->blkcg = blkcg; cpd->plid = pol->plid; - pol->cpd_init_fn(blkcg); + pol->cpd_init_fn(cpd); } } @@ -1186,8 +1188,8 @@ int blkcg_policy_register(struct blkcg_policy *pol) err_free_cpds: if (pol->cpd_size) { list_for_each_entry(blkcg, &all_blkcgs, all_blkcgs_node) { - kfree(blkcg->pd[pol->plid]); - blkcg->pd[pol->plid] = NULL; + kfree(blkcg->cpd[pol->plid]); + blkcg->cpd[pol->plid] = NULL; } } blkcg_policy[pol->plid] = NULL; @@ -1222,8 +1224,8 @@ void blkcg_policy_unregister(struct blkcg_policy *pol) if (pol->cpd_size) { list_for_each_entry(blkcg, &all_blkcgs, all_blkcgs_node) { - kfree(blkcg->pd[pol->plid]); - blkcg->pd[pol->plid] = NULL; + kfree(blkcg->cpd[pol->plid]); + blkcg->cpd[pol->plid] = NULL; } } blkcg_policy[pol->plid] = NULL; diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 95e6b0cbaa84..dd6ea9ee6245 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -220,7 +220,7 @@ struct cfqg_stats { /* Per-cgroup data */ struct cfq_group_data { /* must be the first member */ - struct blkcg_policy_data pd; + struct blkcg_policy_data cpd; unsigned int weight; unsigned int leaf_weight; @@ -612,7 +612,7 @@ static inline struct cfq_group *pd_to_cfqg(struct blkg_policy_data *pd) static struct cfq_group_data *cpd_to_cfqgd(struct blkcg_policy_data *cpd) { - return cpd ? container_of(cpd, struct cfq_group_data, pd) : NULL; + return cpd ? container_of(cpd, struct cfq_group_data, cpd) : NULL; } static inline struct blkcg_gq *cfqg_to_blkg(struct cfq_group *cfqg) @@ -1568,12 +1568,11 @@ static void cfqg_stats_init(struct cfqg_stats *stats) #endif } -static void cfq_cpd_init(const struct blkcg *blkcg) +static void cfq_cpd_init(struct blkcg_policy_data *cpd) { - struct cfq_group_data *cgd = - cpd_to_cfqgd(blkcg->pd[blkcg_policy_cfq.plid]); + struct cfq_group_data *cgd = cpd_to_cfqgd(cpd); - if (blkcg == &blkcg_root) { + if (cpd_to_blkcg(cpd) == &blkcg_root) { cgd->weight = 2 * CFQ_WEIGHT_DEFAULT; cgd->leaf_weight = 2 * CFQ_WEIGHT_DEFAULT; } else { diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index ddd4b8b252c7..7988d4749fff 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -45,7 +45,7 @@ struct blkcg { struct blkcg_gq *blkg_hint; struct hlist_head blkg_list; - struct blkcg_policy_data *pd[BLKCG_MAX_POLS]; + struct blkcg_policy_data *cpd[BLKCG_MAX_POLS]; struct list_head all_blkcgs_node; #ifdef CONFIG_CGROUP_WRITEBACK @@ -88,7 +88,8 @@ struct blkg_policy_data { * each policy handle per-blkcg data. */ struct blkcg_policy_data { - /* the policy id this per-policy data belongs to */ + /* the blkcg and policy id this per-policy data belongs to */ + struct blkcg *blkcg; int plid; }; @@ -123,7 +124,7 @@ struct blkcg_gq { struct rcu_head rcu_head; }; -typedef void (blkcg_pol_init_cpd_fn)(const struct blkcg *blkcg); +typedef void (blkcg_pol_init_cpd_fn)(struct blkcg_policy_data *cpd); typedef struct blkg_policy_data *(blkcg_pol_alloc_pd_fn)(gfp_t gfp, int node); typedef void (blkcg_pol_init_pd_fn)(struct blkg_policy_data *pd); typedef void (blkcg_pol_online_pd_fn)(struct blkg_policy_data *pd); @@ -243,7 +244,7 @@ static inline struct blkg_policy_data *blkg_to_pd(struct blkcg_gq *blkg, static inline struct blkcg_policy_data *blkcg_to_cpd(struct blkcg *blkcg, struct blkcg_policy *pol) { - return blkcg ? blkcg->pd[pol->plid] : NULL; + return blkcg ? blkcg->cpd[pol->plid] : NULL; } /** @@ -257,6 +258,11 @@ static inline struct blkcg_gq *pd_to_blkg(struct blkg_policy_data *pd) return pd ? pd->blkg : NULL; } +static inline struct blkcg *cpd_to_blkcg(struct blkcg_policy_data *cpd) +{ + return cpd ? cpd->blkcg : NULL; +} + /** * blkg_path - format cgroup path of blkg * @blkg: blkg of interest