From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: [PATCH 06/51] memcg: add mem_cgroup_root_css Date: Fri, 22 May 2015 17:13:20 -0400 Message-ID: <1432329245-5844-7-git-send-email-tj@kernel.org> References: <1432329245-5844-1-git-send-email-tj@kernel.org> Cc: linux-kernel@vger.kernel.org, jack@suse.cz, hch@infradead.org, hannes@cmpxchg.org, linux-fsdevel@vger.kernel.org, vgoyal@redhat.com, lizefan@huawei.com, cgroups@vger.kernel.org, linux-mm@kvack.org, mhocko@suse.cz, clm@fb.com, fengguang.wu@intel.com, david@fromorbit.com, gthelen@google.com, khlebnikov@yandex-team.ru, Tejun Heo To: axboe@kernel.dk Return-path: In-Reply-To: <1432329245-5844-1-git-send-email-tj@kernel.org> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org Add global mem_cgroup_root_css which points to the root memcg css. This will be used by cgroup writeback support. If memcg is disabled, it's defined as ERR_PTR(-EINVAL). Signed-off-by: Tejun Heo Cc: Johannes Weiner aCc: Michal Hocko --- include/linux/memcontrol.h | 4 ++++ mm/memcontrol.c | 2 ++ 2 files changed, 6 insertions(+) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 5fe6411..294498f 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -68,6 +68,8 @@ enum mem_cgroup_events_index { }; #ifdef CONFIG_MEMCG +extern struct cgroup_subsys_state *mem_cgroup_root_css; + void mem_cgroup_events(struct mem_cgroup *memcg, enum mem_cgroup_events_index idx, unsigned int nr); @@ -196,6 +198,8 @@ void mem_cgroup_split_huge_fixup(struct page *head); #else /* CONFIG_MEMCG */ struct mem_cgroup; +#define mem_cgroup_root_css ((struct cgroup_subsys_state *)ERR_PTR(-EINVAL)) + static inline void mem_cgroup_events(struct mem_cgroup *memcg, enum mem_cgroup_events_index idx, unsigned int nr) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index c23c1a3..b22a92b 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -77,6 +77,7 @@ EXPORT_SYMBOL(memory_cgrp_subsys); #define MEM_CGROUP_RECLAIM_RETRIES 5 static struct mem_cgroup *root_mem_cgroup __read_mostly; +struct cgroup_subsys_state *mem_cgroup_root_css __read_mostly; /* Whether the swap controller is active */ #ifdef CONFIG_MEMCG_SWAP @@ -4441,6 +4442,7 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) /* root ? */ if (parent_css == NULL) { root_mem_cgroup = memcg; + mem_cgroup_root_css = &memcg->css; page_counter_init(&memcg->memory, NULL); memcg->high = PAGE_COUNTER_MAX; memcg->soft_limit = PAGE_COUNTER_MAX; -- 2.4.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org