From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 85D53C64EB8 for ; Tue, 9 Oct 2018 12:36:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 44E47214C4 for ; Tue, 9 Oct 2018 12:36:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 44E47214C4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727005AbeJITxX (ORCPT ); Tue, 9 Oct 2018 15:53:23 -0400 Received: from mx2.suse.de ([195.135.220.15]:35958 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726600AbeJITxX (ORCPT ); Tue, 9 Oct 2018 15:53:23 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 993C1AE19; Tue, 9 Oct 2018 12:36:36 +0000 (UTC) Date: Tue, 9 Oct 2018 14:36:35 +0200 From: Michal Hocko To: David Rientjes Cc: "Kirill A. Shutemov" , Andrew Morton , Mel Gorman , Vlastimil Babka , Andrea Argangeli , Zi Yan , Stefan Priebe - Profihost AG , linux-mm@kvack.org, LKML Subject: Re: [PATCH 2/2] mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask Message-ID: <20181009123635.GO8528@dhcp22.suse.cz> References: <20180925120326.24392-1-mhocko@kernel.org> <20180925120326.24392-3-mhocko@kernel.org> <20180926133039.y7o5x4nafovxzh2s@kshutemo-mobl1> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 04-10-18 13:17:52, David Rientjes wrote: > On Wed, 26 Sep 2018, Kirill A. Shutemov wrote: > > > On Tue, Sep 25, 2018 at 02:03:26PM +0200, Michal Hocko wrote: > > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > > > index c3bc7e9c9a2a..c0bcede31930 100644 > > > --- a/mm/huge_memory.c > > > +++ b/mm/huge_memory.c > > > @@ -629,21 +629,40 @@ static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf, > > > * available > > > * never: never stall for any thp allocation > > > */ > > > -static inline gfp_t alloc_hugepage_direct_gfpmask(struct vm_area_struct *vma) > > > +static inline gfp_t alloc_hugepage_direct_gfpmask(struct vm_area_struct *vma, unsigned long addr) > > > { > > > const bool vma_madvised = !!(vma->vm_flags & VM_HUGEPAGE); > > > + gfp_t this_node = 0; > > > + > > > +#ifdef CONFIG_NUMA > > > + struct mempolicy *pol; > > > + /* > > > + * __GFP_THISNODE is used only when __GFP_DIRECT_RECLAIM is not > > > + * specified, to express a general desire to stay on the current > > > + * node for optimistic allocation attempts. If the defrag mode > > > + * and/or madvise hint requires the direct reclaim then we prefer > > > + * to fallback to other node rather than node reclaim because that > > > + * can lead to excessive reclaim even though there is free memory > > > + * on other nodes. We expect that NUMA preferences are specified > > > + * by memory policies. > > > + */ > > > + pol = get_vma_policy(vma, addr); > > > + if (pol->mode != MPOL_BIND) > > > + this_node = __GFP_THISNODE; > > > + mpol_cond_put(pol); > > > +#endif > > > > I'm not very good with NUMA policies. Could you explain in more details how > > the code above is equivalent to the code below? > > > > It breaks mbind() because new_page() is now using numa_node_id() to > allocate migration targets for instead of using the mempolicy. I'm not > sure that this patch was tested for mbind(). I am sorry but I do not follow, could you be more specific please? MPOL_BIND should never get __GFP_THISNODE. What am I missing? -- Michal Hocko SUSE Labs