From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f172.google.com (mail-wi0-f172.google.com [209.85.212.172]) by kanga.kvack.org (Postfix) with ESMTP id 15E1F6B0255 for ; Tue, 15 Sep 2015 09:56:26 -0400 (EDT) Received: by wicge5 with SMTP id ge5so30361123wic.0 for ; Tue, 15 Sep 2015 06:56:25 -0700 (PDT) Received: from mail-wi0-f172.google.com (mail-wi0-f172.google.com. [209.85.212.172]) by mx.google.com with ESMTPS id lk14si24565957wic.120.2015.09.15.06.56.24 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 15 Sep 2015 06:56:24 -0700 (PDT) Received: by wiclk2 with SMTP id lk2so30106043wic.0 for ; Tue, 15 Sep 2015 06:56:24 -0700 (PDT) Date: Tue, 15 Sep 2015 15:56:23 +0200 From: Michal Hocko Subject: Re: [PATCH] mm: memcontrol: fix order calculation in try_charge() Message-ID: <20150915135623.GA26649@dhcp22.suse.cz> References: <1442318757-7141-1-git-send-email-jmarchan@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1442318757-7141-1-git-send-email-jmarchan@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Jerome Marchand Cc: Johannes Weiner , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org On Tue 15-09-15 14:05:57, Jerome Marchand wrote: > Since commit <6539cc05386> (mm: memcontrol: fold mem_cgroup_do_charge()), > the order to pass to mem_cgroup_oom() is calculated by passing the number > of pages to get_order() instead of the expected size in bytes. AFAICT, > it only affects the value displayed in the oom warning message. > This patch fix this. We haven't noticed that just because the OOM is enabled only for page faults of order-0 (single page) and get_order work just fine. Thanks for noticing this. If we ever start triggering OOM on different orders this would be broken. > Signed-off-by: Jerome Marchand Acked-by: Michal Hocko Btw. a quick git grep shows that at least gart_iommu_init is using number of pages as well. I haven't checked it does that intentionally, though. Thanks! > --- > mm/memcontrol.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 1742a2d..91bf094 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -2032,7 +2032,8 @@ retry: > > mem_cgroup_events(mem_over_limit, MEMCG_OOM, 1); > > - mem_cgroup_oom(mem_over_limit, gfp_mask, get_order(nr_pages)); > + mem_cgroup_oom(mem_over_limit, gfp_mask, > + get_order(nr_pages * PAGE_SIZE)); > nomem: > if (!(gfp_mask & __GFP_NOFAIL)) > return -ENOMEM; > -- > 1.9.3 -- 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