From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f69.google.com (mail-oi0-f69.google.com [209.85.218.69]) by kanga.kvack.org (Postfix) with ESMTP id A12806B0253 for ; Mon, 30 May 2016 05:28:41 -0400 (EDT) Received: by mail-oi0-f69.google.com with SMTP id w143so266355185oiw.3 for ; Mon, 30 May 2016 02:28:41 -0700 (PDT) Received: from mail-it0-x241.google.com (mail-it0-x241.google.com. [2607:f8b0:4001:c0b::241]) by mx.google.com with ESMTPS id r16si24380316ign.98.2016.05.30.02.28.41 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 30 May 2016 02:28:41 -0700 (PDT) Received: by mail-it0-x241.google.com with SMTP id k76so6136383ita.1 for ; Mon, 30 May 2016 02:28:41 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20160530085311.GM22928@dhcp22.suse.cz> References: <1464597951-2976-1-git-send-email-wwtao0320@163.com> <20160530085311.GM22928@dhcp22.suse.cz> Date: Mon, 30 May 2016 17:28:40 +0800 Message-ID: Subject: Re: [PATCH] mm/memcontrol.c: add memory allocation result check From: Wenwei Tao Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Wenwei Tao , hannes@cmpxchg.org, vdavydov@virtuozzo.com, cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org I think explicit BUG_ON may make the debug easier, since it can point out the wrong line. 2016-05-30 16:53 GMT+08:00 Michal Hocko : > On Mon 30-05-16 16:45:51, Wenwei Tao wrote: >> From: Wenwei Tao >> >> The mem_cgroup_tree_per_node allocation might fail, >> check that before continue the memcg init. Since it >> is in the init phase, trigger the panic if that failure >> happens. > > We would blow up in the very same function so what is the point of the > explicit BUG_ON? > >> Signed-off-by: Wenwei Tao >> --- >> mm/memcontrol.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/mm/memcontrol.c b/mm/memcontrol.c >> index 925b431..6385c62 100644 >> --- a/mm/memcontrol.c >> +++ b/mm/memcontrol.c >> @@ -5712,6 +5712,7 @@ static int __init mem_cgroup_init(void) >> >> rtpn = kzalloc_node(sizeof(*rtpn), GFP_KERNEL, >> node_online(node) ? node : NUMA_NO_NODE); >> + BUG_ON(!rtpn); >> >> for (zone = 0; zone < MAX_NR_ZONES; zone++) { >> struct mem_cgroup_tree_per_zone *rtpz; >> -- >> 1.8.3.1 >> >> >> -- >> 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 > > -- > Michal Hocko > SUSE Labs -- 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