From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kamezawa Hiroyuki Subject: Re: [patch] mm, memcg: avoid unnecessary function call when memcg is disabled fix Date: Wed, 21 Nov 2012 13:11:11 +0900 Message-ID: <50AC545F.5080303@jp.fujitsu.com> References: <20121120134932.055bc192.akpm@linux-foundation.org> <50AC282A.4070309@jp.fujitsu.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: David Rientjes Cc: Andrew Morton , Johannes Weiner , Michal Hocko , Hugh Dickins , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org (2012/11/21 11:48), David Rientjes wrote: > Move the check for !mm out of line as suggested by Andrew. > > Signed-off-by: David Rientjes Thank you very much ! Acked-by: KAMEZAWA Hiroyuki > --- > include/linux/memcontrol.h | 2 +- > mm/memcontrol.c | 3 +++ > 2 files changed, 4 insertions(+), 1 deletion(-) > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > --- a/include/linux/memcontrol.h > +++ b/include/linux/memcontrol.h > @@ -185,7 +185,7 @@ void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx); > static inline void mem_cgroup_count_vm_event(struct mm_struct *mm, > enum vm_event_item idx) > { > - if (mem_cgroup_disabled() || !mm) > + if (mem_cgroup_disabled()) > return; > __mem_cgroup_count_vm_event(mm, idx); > } > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1021,6 +1021,9 @@ void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx) > { > struct mem_cgroup *memcg; > > + if (!mm) > + return; > + > rcu_read_lock(); > memcg = mem_cgroup_from_task(rcu_dereference(mm->owner)); > if (unlikely(!memcg)) >