diff options
| author | Tejun Heo <tj@kernel.org> | 2014-05-04 21:09:14 +0200 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2014-05-04 21:09:14 +0200 |
| commit | 15a4c835e4ed3e60dd68727cd1907e3dd89563f4 (patch) | |
| tree | 849cef1af88267720ec75def1c05ffe0f41e310e /mm/memcontrol.c | |
| parent | cgroup: update init_css() into init_and_link_css() (diff) | |
| download | linux-15a4c835e4ed3e60dd68727cd1907e3dd89563f4.tar.xz linux-15a4c835e4ed3e60dd68727cd1907e3dd89563f4.zip | |
cgroup, memcg: implement css->id and convert css_from_id() to use it
Until now, cgroup->id has been used to identify all the associated
csses and css_from_id() takes cgroup ID and returns the matching css
by looking up the cgroup and then dereferencing the css associated
with it; however, now that the lifetimes of cgroup and css are
separate, this is incorrect and breaks on the unified hierarchy when a
controller is disabled and enabled back again before the previous
instance is released.
This patch adds css->id which is a subsystem-unique ID and converts
css_from_id() to look up by the new css->id instead. memcg is the
only user of css_from_id() and also converted to use css->id instead.
For traditional hierarchies, this shouldn't make any functional
difference.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jianyu Zhan <nasa4836@gmail.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Diffstat (limited to 'mm/memcontrol.c')
| -rw-r--r-- | mm/memcontrol.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 1d0b29715b73..c3f82f69ef58 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -527,7 +527,7 @@ static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg) static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg) { - return memcg->css.cgroup->id; + return memcg->css.id; } static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id) @@ -6401,7 +6401,7 @@ mem_cgroup_css_online(struct cgroup_subsys_state *css) struct mem_cgroup *memcg = mem_cgroup_from_css(css); struct mem_cgroup *parent = mem_cgroup_from_css(css_parent(css)); - if (css->cgroup->id > MEM_CGROUP_ID_MAX) + if (css->id > MEM_CGROUP_ID_MAX) return -ENOSPC; if (!parent) |