From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-f197.google.com (mail-qk0-f197.google.com [209.85.220.197]) by kanga.kvack.org (Postfix) with ESMTP id 144E56B0005 for ; Mon, 4 Jul 2016 06:39:43 -0400 (EDT) Received: by mail-qk0-f197.google.com with SMTP id r68so158971266qka.3 for ; Mon, 04 Jul 2016 03:39:43 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id x18si1667122qtx.42.2016.07.04.03.39.42 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 04 Jul 2016 03:39:42 -0700 (PDT) Date: Mon, 4 Jul 2016 12:39:32 +0200 From: Oleg Nesterov Subject: Re: [PATCH 3/8] mm,oom: Use list of mm_struct used by OOM victims. Message-ID: <20160704103931.GA3882@redhat.com> References: <201607031135.AAH95347.MVOHQtFJFLOOFS@I-love.SAKURA.ne.jp> <201607031138.AHB35971.FLVQOtJFOMFHSO@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201607031138.AHB35971.FLVQOtJFOMFHSO@I-love.SAKURA.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa Cc: linux-mm@kvack.org, akpm@linux-foundation.org, rientjes@google.com, vdavydov@parallels.com, mst@redhat.com, mhocko@suse.com, mhocko@kernel.org Tetsuo, I'll try to actually read this series later, although I will leave the actual review to maintainers anyway... Just a couple of questions for now, On 07/03, Tetsuo Handa wrote: > > --- a/kernel/fork.c > +++ b/kernel/fork.c > @@ -722,6 +722,7 @@ static inline void __mmput(struct mm_struct *mm) > } > if (mm->binfmt) > module_put(mm->binfmt->module); > + exit_oom_mm(mm); Is it strictly necessary? At first glance not. Sooner or later oom_reaper() should find this mm_struct and do exit_oom_mm(). And given that mm->mm_users is already 0 the "extra" __oom_reap_vmas() doesn't really hurt. It would be nice to remove exit_oom_mm() from __mmput(); it takes the global spinlock for the very unlikely case, and if we can avoid it here then perhaps we can remove ->oom_mm from mm_struct. Oleg. -- 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