From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id CF1C16B025E for ; Mon, 9 Oct 2017 02:33:19 -0400 (EDT) Received: by mail-wm0-f69.google.com with SMTP id u78so26341715wmd.4 for ; Sun, 08 Oct 2017 23:33:19 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id e22si6334230wmi.50.2017.10.08.23.33.18 for (version=TLS1 cipher=AES128-SHA bits=128/128); Sun, 08 Oct 2017 23:33:18 -0700 (PDT) Date: Mon, 9 Oct 2017 08:33:16 +0200 From: Michal Hocko Subject: Re: [PATCH 3/3] mm: oom: show unreclaimable slab info when unreclaimable slabs > user memory Message-ID: <20171009063316.qjmunbabyr2nzh52@dhcp22.suse.cz> References: <1507152550-46205-1-git-send-email-yang.s@alibaba-inc.com> <1507152550-46205-4-git-send-email-yang.s@alibaba-inc.com> <20171006093702.3ca2p6ymyycwfgbk@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Yang Shi Cc: cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org On Sat 07-10-17 00:37:55, Yang Shi wrote: > > > On 10/6/17 2:37 AM, Michal Hocko wrote: > > On Thu 05-10-17 05:29:10, Yang Shi wrote: [...] > > > + list_for_each_entry_safe(s, s2, &slab_caches, list) { > > > + if (!is_root_cache(s) || (s->flags & SLAB_RECLAIM_ACCOUNT)) > > > + continue; > > > + > > > + memset(&sinfo, 0, sizeof(sinfo)); > > > > why do you zero out the structure. All the fields you are printing are > > filled out in get_slabinfo. > > No special reason, just wipe out the potential stale data on the stack. Do not add code that has no meaning. The OOM killer is a slow path but that doesn't mean we should throw spare cycles out of the window. -- 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