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| author | Tejun Heo <tj@kernel.org> | 2015-08-18 14:55:08 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2015-08-18 15:49:16 -0700 |
| commit | bc915e61cde25d0b429f536cec9e83039bf23504 (patch) | |
| tree | 9782354c7f36f1fcc3c2ada7b12937c45b309028 /block | |
| parent | 994b78327458ea14a1743196ee0560c73ace37f3 (diff) | |
| download | linux-bc915e61cde25d0b429f536cec9e83039bf23504.tar.gz linux-bc915e61cde25d0b429f536cec9e83039bf23504.tar.bz2 linux-bc915e61cde25d0b429f536cec9e83039bf23504.zip | |
blkcg: remove unnecessary blkcg_root handling from css_alloc/free paths
blkcg_css_alloc() bypasses policy data allocation and blkcg_css_free()
bypasses policy data and blkcg freeing for blkcg_root. There's no
reason to to treat policy data any differently for blkcg_root. If the
root css gets allocated after policies are registered, policy
registration path will add policy data; otherwise, the alloc path
will. The free path isn't never invoked for root csses.
This patch removes the unnecessary special handling of blkcg_root from
css_alloc/free paths.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-cgroup.c | 25 |
1 files changed, 10 insertions, 15 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index cd251830038a..f91a4e09e0c9 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -823,18 +823,15 @@ static void blkcg_css_offline(struct cgroup_subsys_state *css) static void blkcg_css_free(struct cgroup_subsys_state *css) { struct blkcg *blkcg = css_to_blkcg(css); + int i; mutex_lock(&blkcg_pol_mutex); list_del(&blkcg->all_blkcgs_node); mutex_unlock(&blkcg_pol_mutex); - if (blkcg != &blkcg_root) { - int i; - - for (i = 0; i < BLKCG_MAX_POLS; i++) - kfree(blkcg->pd[i]); - kfree(blkcg); - } + for (i = 0; i < BLKCG_MAX_POLS; i++) + kfree(blkcg->pd[i]); + kfree(blkcg); } static struct cgroup_subsys_state * @@ -848,13 +845,12 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css) if (!parent_css) { blkcg = &blkcg_root; - goto done; - } - - blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL); - if (!blkcg) { - ret = ERR_PTR(-ENOMEM); - goto free_blkcg; + } else { + blkcg = kzalloc(sizeof(*blkcg), GFP_KERNEL); + if (!blkcg) { + ret = ERR_PTR(-ENOMEM); + goto free_blkcg; + } } for (i = 0; i < BLKCG_MAX_POLS ; i++) { @@ -881,7 +877,6 @@ blkcg_css_alloc(struct cgroup_subsys_state *parent_css) pol->cpd_init_fn(blkcg); } -done: spin_lock_init(&blkcg->lock); INIT_RADIX_TREE(&blkcg->blkg_tree, GFP_NOWAIT); INIT_HLIST_HEAD(&blkcg->blkg_list); |