From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753773Ab2GWBpj (ORCPT ); Sun, 22 Jul 2012 21:45:39 -0400 Received: from e28smtp06.in.ibm.com ([122.248.162.6]:45356 "EHLO e28smtp06.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753747Ab2GWBpg (ORCPT ); Sun, 22 Jul 2012 21:45:36 -0400 From: Wanpeng Li To: Andrew Morton Cc: Fengguang Wu , Seth Jennings , "Kirill A. Shutemov" , linux-mm@kvack.org, Michal Hocko , Johannes Weiner , KAMEZAWAHiroyuki , Gavin Shan , linux-kernel@vger.kernel.org, Wanpeng Li Subject: [PATCH v2] memcg: add mem_cgroup_from_css() helper Date: Mon, 23 Jul 2012 09:44:23 +0800 Message-Id: <1343007863-18144-1-git-send-email-liwanp@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.5.4 x-cbid: 12072301-9574-0000-0000-000003A9704E Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Signed-off-by: Wanpeng Li --- 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 @@ -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