Re: [PATCH v2] memcg: add mem_cgroup_from_css() helper

Gavin Shan
2012-07-23T02:09:08Z

For this case, we usually fix the build error on top of linux-next.
It seems that you're changing the original patch and send again, which
isn't reasonable, man :-)

Thanks,
Gavin

>Changelog v2:
>* fix too many args to mem_cgroup_from_css() (spotted by Kirill A. Shutemov)
>* fix kernel build failed (spotted by Fengguang)
>
>Add a mem_cgroup_from_css() helper to replace open-coded invokations of
>container_of(). To clarify the code and to add a little more type safety.
>
>Acked-by: Michal Hocko <mhocko@suse.cz>
>Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
>
>---
> mm/memcontrol.c | 19 +++++++++++--------
> 1 files changed, 11 insertions(+), 8 deletions(-)
>
>diff --git a/mm/memcontrol.c b/mm/memcontrol.c
>index 883283d..f0c7639 100644
>--- a/mm/memcontrol.c
>+++ b/mm/memcontrol.c
>@@ -407,6 +407,12 @@ enum charge_type {
> static void mem_cgroup_get(struct mem_cgroup *memcg);
> static void mem_cgroup_put(struct mem_cgroup *memcg);
>
>+static inline
>+struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *s)
>+{
>+ return container_of(s, struct mem_cgroup, css);
>+}
>+
> /* Writing them here to avoid exposing memcg's inner layout */
> #ifdef CONFIG_CGROUP_MEM_RES_CTLR_KMEM
> #include <net/sock.h>
>@@ -864,9 +870,8 @@ static void memcg_check_events(struct mem_cgroup *memcg, struct page *page)
>
> struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont)
> {
>- return container_of(cgroup_subsys_state(cont,
>- mem_cgroup_subsys_id), struct mem_cgroup,
>- css);
>+ return mem_cgroup_from_css(cgroup_subsys_state(cont,
>+ mem_cgroup_subsys_id));
> }
>
> struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p)
>@@ -879,8 +884,7 @@ struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p)
> if (unlikely(!p))
> return NULL;
>
>- return container_of(task_subsys_state(p, mem_cgroup_subsys_id),
>- struct mem_cgroup, css);
>+ return mem_cgroup_from_css(task_subsys_state(p, mem_cgroup_subsys_id));
> }
>
> struct mem_cgroup *try_get_mem_cgroup_from_mm(struct mm_struct *mm)
>@@ -966,8 +970,7 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root,
> css = css_get_next(&mem_cgroup_subsys, id + 1, &root->css, &id);
> if (css) {
> if (css == &root->css || css_tryget(css))
>- memcg = container_of(css,
>- struct mem_cgroup, css);
>+ memcg = mem_cgroup_from_css(css);
> } else
> id = 0;
> rcu_read_unlock();
>@@ -2429,7 +2432,7 @@ static struct mem_cgroup *mem_cgroup_lookup(unsigned short id)
> css = css_lookup(&mem_cgroup_subsys, id);
> if (!css)
> return NULL;
>- return container_of(css, struct mem_cgroup, css);
>+ return mem_cgroup_from_css(css);
> }
>
> struct mem_cgroup *try_get_mem_cgroup_from_page(struct page *page)
>--
>1.7.7.6