From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f43.google.com (mail-pa0-f43.google.com [209.85.220.43]) by kanga.kvack.org (Postfix) with ESMTP id A2B296B0254 for ; Tue, 1 Mar 2016 04:28:30 -0500 (EST) Received: by mail-pa0-f43.google.com with SMTP id fy10so108820504pac.1 for ; Tue, 01 Mar 2016 01:28:30 -0800 (PST) Received: from mx2.parallels.com (mx2.parallels.com. [199.115.105.18]) by mx.google.com with ESMTPS id t63si49266489pfa.240.2016.03.01.01.28.29 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 01 Mar 2016 01:28:29 -0800 (PST) From: Vladimir Davydov Subject: [PATCH -mm] oom: make oom_reaper_list single linked Date: Tue, 1 Mar 2016 12:28:20 +0300 Message-ID: <1456824500-30661-1-git-send-email-vdavydov@virtuozzo.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Michal Hocko , Tetsuo Handa , linux-mm@kvack.org, linux-kernel@vger.kernel.org Entries are only added/removed from oom_reaper_list at head so we can use a single linked list and hence save a word in task_struct. Signed-off-by: Vladimir Davydov --- include/linux/sched.h | 2 +- mm/oom_kill.c | 15 +++++++-------- 2 files changed, 8 insertions(+), 9 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 2118e963fba7..7b76e65595c3 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1853,7 +1853,7 @@ struct task_struct { #endif int pagefault_disabled; #ifdef CONFIG_MMU - struct list_head oom_reaper_list; + struct task_struct *oom_reaper_list; #endif /* CPU-specific state of this task */ struct thread_struct thread; diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 5d5eca9d6737..1a91d9a26bc9 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -423,7 +423,7 @@ bool oom_killer_disabled __read_mostly; */ static struct task_struct *oom_reaper_th; static DECLARE_WAIT_QUEUE_HEAD(oom_reaper_wait); -static LIST_HEAD(oom_reaper_list); +static struct task_struct *oom_reaper_list; static DEFINE_SPINLOCK(oom_reaper_lock); @@ -530,13 +530,11 @@ static int oom_reaper(void *unused) while (true) { struct task_struct *tsk = NULL; - wait_event_freezable(oom_reaper_wait, - (!list_empty(&oom_reaper_list))); + wait_event_freezable(oom_reaper_wait, oom_reaper_list != NULL); spin_lock(&oom_reaper_lock); - if (!list_empty(&oom_reaper_list)) { - tsk = list_first_entry(&oom_reaper_list, - struct task_struct, oom_reaper_list); - list_del(&tsk->oom_reaper_list); + if (oom_reaper_list != NULL) { + tsk = oom_reaper_list; + oom_reaper_list = tsk->oom_reaper_list; } spin_unlock(&oom_reaper_lock); @@ -555,7 +553,8 @@ static void wake_oom_reaper(struct task_struct *tsk) get_task_struct(tsk); spin_lock(&oom_reaper_lock); - list_add(&tsk->oom_reaper_list, &oom_reaper_list); + tsk->oom_reaper_list = oom_reaper_list; + oom_reaper_list = tsk; spin_unlock(&oom_reaper_lock); wake_up(&oom_reaper_wait); } -- 2.1.4 -- 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