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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 0F4B9C433DB for ; Wed, 10 Mar 2021 09:45:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AAE9D64FE3 for ; Wed, 10 Mar 2021 09:45:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232499AbhCJJol (ORCPT ); Wed, 10 Mar 2021 04:44:41 -0500 Received: from mx2.suse.de ([195.135.220.15]:51478 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232479AbhCJJoN (ORCPT ); Wed, 10 Mar 2021 04:44:13 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1615369452; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=3SsgBHW16eFWnTUrEH/77iFpVMjIm1pROOU1P8F4Mng=; b=Npfk496kGiHkf4as0AZ+Zg1Csp7luUcJauh0vcSnRMePUC5McZDgwhvAyoDjRmPedo9h78 4ydozO4Se11nTVuHJ/nzYvi9WbUb7OFZkXtD1JhdIF1h0uWxv0ZIgYg7sjQGUSrvqxFJ4g xuYQ55aaqua7NEO1Wl9PEoSg8tccWCQ= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 793B2AE42; Wed, 10 Mar 2021 09:44:12 +0000 (UTC) Date: Wed, 10 Mar 2021 10:44:11 +0100 From: Michal Hocko To: Feng Tang Cc: Dave Hansen , Ben Widawsky , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Andrew Morton , Andrea Arcangeli , David Rientjes , Mel Gorman , Mike Kravetz , Randy Dunlap , Vlastimil Babka , Andi Kleen , "Williams, Dan J" Subject: Re: [PATCH v3 RFC 14/14] mm: speedup page alloc for MPOL_PREFERRED_MANY by adding a NO_SLOWPATH gfp bit Message-ID: References: <20210303120717.GA16736@shbuild999.sh.intel.com> <20210303121833.GB16736@shbuild999.sh.intel.com> <20210303131832.GB78458@shbuild999.sh.intel.com> <20210303134644.GC78458@shbuild999.sh.intel.com> <20210303163141.v5wu2sfo2zj2qqsw@intel.com> <20210310051947.GA33036@shbuild999.sh.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210310051947.GA33036@shbuild999.sh.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 10-03-21 13:19:47, Feng Tang wrote: [...] > diff --git a/mm/mempolicy.c b/mm/mempolicy.c > index d66c1c0..00b19f7 100644 > --- a/mm/mempolicy.c > +++ b/mm/mempolicy.c > @@ -2205,9 +2205,13 @@ static struct page *alloc_pages_policy(struct mempolicy *pol, gfp_t gfp, > * | MPOL_PREFERRED_MANY (round 2) | local | NULL | > * +-------------------------------+---------------+------------+ > */ > - if (pol->mode == MPOL_PREFERRED_MANY) > + if (pol->mode == MPOL_PREFERRED_MANY) { > gfp_mask |= __GFP_RETRY_MAYFAIL | __GFP_NOWARN; > > + /* Skip direct reclaim, as there will be a second try */ > + gfp_mask &= ~__GFP_DIRECT_RECLAIM; __GFP_RETRY_MAYFAIL is a reclaim modifier which doesn't make any sense without __GFP_DIRECT_RECLAIM. Also I think it would be better to have a proper allocation flags in the initial patch which implements the fallback. > + } > + > page = __alloc_pages_nodemask(gfp_mask, order, > policy_node(gfp, pol, preferred_nid), > policy_nodemask(gfp, pol)); > -- > 2.7.4 > > -- Michal Hocko SUSE Labs