diff options
| author |   Tejun Heo <tj@kernel.org> | 2012-03-05 13:15:04 -0800 |
|---|---|---|
| committer |   Jens Axboe <axboe@kernel.dk> | 2012-03-06 21:27:22 +0100 |
| commit | 035d10b2fa7e5f7e9bf9465dbc39c35affd5ac32 (patch) | |
| tree | 6a712eb1b505e8163d28f8709980e581a08b572c | |
| parent | blkcg: use q and plid instead of opaque void * for blkio_group association (diff) | |
| download | linux-dev-035d10b2fa7e5f7e9bf9465dbc39c35affd5ac32.tar.xz linux-dev-035d10b2fa7e5f7e9bf9465dbc39c35affd5ac32.zip | |
blkcg: add blkio_policy[] array and allow one policy per policy ID
Block cgroup policies are maintained in a linked list and,
theoretically, multiple policies sharing the same policy ID are
allowed.
This patch temporarily restricts one policy per plid and adds
blkio_policy[] array which indexes registered policy types by plid.
Both the restriction and blkio_policy[] array are transitional and
will be removed once API cleanup is complete.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/blk-cgroup.c | 10 | ||||
| -rw-r--r-- | block/blk-cgroup.h | 2 |
2 files changed, 12 insertions, 0 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 5e50ca1f5b47..f1b08d3cba55 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -29,6 +29,8 @@ static LIST_HEAD(blkio_list); struct blkio_cgroup blkio_root_cgroup = { .weight = 2*BLKIO_WEIGHT_DEFAULT }; EXPORT_SYMBOL_GPL(blkio_root_cgroup); +static struct blkio_policy_type *blkio_policy[BLKIO_NR_POLICIES]; + static struct cgroup_subsys_state *blkiocg_create(struct cgroup_subsys *, struct cgroup *); static int blkiocg_can_attach(struct cgroup_subsys *, struct cgroup *, @@ -1694,7 +1696,11 @@ static void blkiocg_attach(struct cgroup_subsys *ss, struct cgroup *cgrp, void blkio_policy_register(struct blkio_policy_type *blkiop) { spin_lock(&blkio_list_lock); + + BUG_ON(blkio_policy[blkiop->plid]); + blkio_policy[blkiop->plid] = blkiop; list_add_tail(&blkiop->list, &blkio_list); + spin_unlock(&blkio_list_lock); } EXPORT_SYMBOL_GPL(blkio_policy_register); @@ -1702,7 +1708,11 @@ EXPORT_SYMBOL_GPL(blkio_policy_register); void blkio_policy_unregister(struct blkio_policy_type *blkiop) { spin_lock(&blkio_list_lock); + + BUG_ON(blkio_policy[blkiop->plid] != blkiop); + blkio_policy[blkiop->plid] = NULL; list_del_init(&blkiop->list); + spin_unlock(&blkio_list_lock); } EXPORT_SYMBOL_GPL(blkio_policy_unregister); diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index 41c960b99c57..562fa55d97b1 100644 --- a/block/blk-cgroup.h +++ b/block/blk-cgroup.h @@ -19,6 +19,8 @@ enum blkio_policy_id { BLKIO_POLICY_PROP = 0, /* Proportional Bandwidth division */ BLKIO_POLICY_THROTL, /* Throttling */ + + BLKIO_NR_POLICIES, }; /* Max limits for throttle policy */ |