From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f200.google.com (mail-pf0-f200.google.com [209.85.192.200]) by kanga.kvack.org (Postfix) with ESMTP id 774D06B007E for ; Thu, 14 Apr 2016 16:22:33 -0400 (EDT) Received: by mail-pf0-f200.google.com with SMTP id u190so148672968pfb.0 for ; Thu, 14 Apr 2016 13:22:33 -0700 (PDT) Received: from mail-pf0-x235.google.com (mail-pf0-x235.google.com. [2607:f8b0:400e:c00::235]) by mx.google.com with ESMTPS id gl9si12208993pac.111.2016.04.14.13.22.32 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 14 Apr 2016 13:22:32 -0700 (PDT) Received: by mail-pf0-x235.google.com with SMTP id n1so49209401pfn.2 for ; Thu, 14 Apr 2016 13:22:32 -0700 (PDT) Date: Thu, 14 Apr 2016 13:22:30 -0700 (PDT) From: David Rientjes Subject: Re: [patch v2] mm, hugetlb_cgroup: round limit_in_bytes down to hugepage size In-Reply-To: <20160407125145.GD32755@dhcp22.suse.cz> Message-ID: References: <5704BA37.2080508@kyup.com> <5704BBBF.8040302@kyup.com> <20160407125145.GD32755@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Andrew Morton , Nikolay Borisov , Johannes Weiner , "Kirill A. Shutemov" , linux-kernel@vger.kernel.org, linux-mm@kvack.org On Thu, 7 Apr 2016, Michal Hocko wrote: > > +static void hugetlb_cgroup_init(struct hugetlb_cgroup *h_cgroup, > > + struct hugetlb_cgroup *parent_h_cgroup) > > +{ > > + int idx; > > + > > + for (idx = 0; idx < HUGE_MAX_HSTATE; idx++) { > > + struct page_counter *counter = &h_cgroup->hugepage[idx]; > > + struct page_counter *parent = NULL; > > + unsigned long limit; > > + int ret; > > + > > + if (parent_h_cgroup) > > + parent = &parent_h_cgroup->hugepage[idx]; > > + page_counter_init(counter, parent); > > + > > + limit = round_down(PAGE_COUNTER_MAX, > > + 1 << huge_page_order(&hstates[idx])); > > + ret = page_counter_limit(counter, limit); > > + VM_BUG_ON(ret); > > + } > > +} > > I fail to see the point for this. Why would want to round down > PAGE_COUNTER_MAX? It will never make a real difference. Or am I missing > something? Did you try the patch? If we're rounding down the user value, it makes sense to be consistent with the upper bound default to specify intent. -- 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