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| author | Tejun Heo <tj@kernel.org> | 2013-01-09 08:05:12 -0800 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2013-01-09 08:05:12 -0800 |
| commit | f427d909648aa592c9588d0f66b5b457752a0cd1 (patch) | |
| tree | d6f91a6d46a1302f0cca6137851f0806364b7965 /block | |
| parent | b276a876a014c5fa58a16f247c0933f6c42112e3 (diff) | |
| download | kernel-common-f427d909648aa592c9588d0f66b5b457752a0cd1.tar.gz kernel-common-f427d909648aa592c9588d0f66b5b457752a0cd1.tar.bz2 kernel-common-f427d909648aa592c9588d0f66b5b457752a0cd1.zip | |
blkcg: implement blkcg_policy->on/offline_pd_fn() and blkcg_gq->online
Add two blkcg_policy methods, ->online_pd_fn() and ->offline_pd_fn(),
which are invoked as the policy_data gets activated and deactivated
while holding both blkcg and q locks.
Also, add blkcg_gq->online bool, which is set and cleared as the
blkcg_gq gets activated and deactivated. This flag also is toggled
while holding both blkcg and q locks.
These will be used to implement hierarchical stats.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-cgroup.c | 21 | ||||
| -rw-r--r-- | block/blk-cgroup.h | 7 |
2 files changed, 27 insertions, 1 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 3a8de321d1f6..4d625d28e070 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -182,7 +182,7 @@ static struct blkcg_gq *blkg_create(struct blkcg *blkcg, struct blkcg_gq *new_blkg) { struct blkcg_gq *blkg; - int ret; + int i, ret; WARN_ON_ONCE(!rcu_read_lock_held()); lockdep_assert_held(q->queue_lock); @@ -218,7 +218,15 @@ static struct blkcg_gq *blkg_create(struct blkcg *blkcg, if (likely(!ret)) { hlist_add_head_rcu(&blkg->blkcg_node, &blkcg->blkg_list); list_add(&blkg->q_node, &q->blkg_list); + + for (i = 0; i < BLKCG_MAX_POLS; i++) { + struct blkcg_policy *pol = blkcg_policy[i]; + + if (blkg->pd[i] && pol->pd_online_fn) + pol->pd_online_fn(blkg); + } } + blkg->online = true; spin_unlock(&blkcg->lock); if (!ret) @@ -291,6 +299,7 @@ EXPORT_SYMBOL_GPL(blkg_lookup_create); static void blkg_destroy(struct blkcg_gq *blkg) { struct blkcg *blkcg = blkg->blkcg; + int i; lockdep_assert_held(blkg->q->queue_lock); lockdep_assert_held(&blkcg->lock); @@ -299,6 +308,14 @@ static void blkg_destroy(struct blkcg_gq *blkg) WARN_ON_ONCE(list_empty(&blkg->q_node)); WARN_ON_ONCE(hlist_unhashed(&blkg->blkcg_node)); + for (i = 0; i < BLKCG_MAX_POLS; i++) { + struct blkcg_policy *pol = blkcg_policy[i]; + + if (blkg->pd[i] && pol->pd_offline_fn) + pol->pd_offline_fn(blkg); + } + blkg->online = false; + radix_tree_delete(&blkcg->blkg_tree, blkg->q->id); list_del_init(&blkg->q_node); hlist_del_init_rcu(&blkg->blkcg_node); @@ -956,6 +973,8 @@ void blkcg_deactivate_policy(struct request_queue *q, /* grab blkcg lock too while removing @pd from @blkg */ spin_lock(&blkg->blkcg->lock); + if (pol->pd_offline_fn) + pol->pd_offline_fn(blkg); if (pol->pd_exit_fn) pol->pd_exit_fn(blkg); diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index 40f5b9768aac..678e89ed8ecb 100644 --- a/block/blk-cgroup.h +++ b/block/blk-cgroup.h @@ -106,12 +106,17 @@ struct blkcg_gq { /* reference count */ int refcnt; + /* is this blkg online? protected by both blkcg and q locks */ + bool online; + struct blkg_policy_data *pd[BLKCG_MAX_POLS]; struct rcu_head rcu_head; }; typedef void (blkcg_pol_init_pd_fn)(struct blkcg_gq *blkg); +typedef void (blkcg_pol_online_pd_fn)(struct blkcg_gq *blkg); +typedef void (blkcg_pol_offline_pd_fn)(struct blkcg_gq *blkg); typedef void (blkcg_pol_exit_pd_fn)(struct blkcg_gq *blkg); typedef void (blkcg_pol_reset_pd_stats_fn)(struct blkcg_gq *blkg); @@ -124,6 +129,8 @@ struct blkcg_policy { /* operations */ blkcg_pol_init_pd_fn *pd_init_fn; + blkcg_pol_online_pd_fn *pd_online_fn; + blkcg_pol_offline_pd_fn *pd_offline_fn; blkcg_pol_exit_pd_fn *pd_exit_fn; blkcg_pol_reset_pd_stats_fn *pd_reset_stats_fn; }; |