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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 0FFC8C4707F for ; Thu, 27 May 2021 13:15:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E142F6128B for ; Thu, 27 May 2021 13:15:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236358AbhE0NQn (ORCPT ); Thu, 27 May 2021 09:16:43 -0400 Received: from mx2.suse.de ([195.135.220.15]:52090 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235996AbhE0NQl (ORCPT ); Thu, 27 May 2021 09:16:41 -0400 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=1622121308; 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=NWh10ATxyrNz9Z6Ew/1MC4tHYel7uPGah1gbH11QuB4=; b=q0RMs+CZTPYRVo07bfTkV9yM8bbBiS+U2g4J8uPB7fbTbQO8Iv5JQppG+PujD1FSH0pSj+ t65H8NMpWPZFULTkg1LAeOqZr8mtGyy6qDyhAVcGpXQiodUQRf8ezZqrAAECkrvvVClqw7 Qahwx3UV1nFRgDP/aPRu+CQvVuOs+EU= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id E5137AE86; Thu, 27 May 2021 13:15:07 +0000 (UTC) Date: Thu, 27 May 2021 15:15:04 +0200 From: Michal Hocko To: Feng Tang Cc: linux-mm@kvack.org, Andrew Morton , David Rientjes , Dave Hansen , Ben Widawsky , linux-kernel@vger.kernel.org, Andrea Arcangeli , Mel Gorman , Mike Kravetz , Randy Dunlap , Vlastimil Babka , Andi Kleen , Dan Williams , ying.huang@intel.com Subject: Re: [PATCH v1 1/4] mm/mempolicy: skip nodemask intersect check for 'interleave' when oom Message-ID: References: <1622005302-23027-1-git-send-email-feng.tang@intel.com> <1622005302-23027-2-git-send-email-feng.tang@intel.com> <20210527130501.GC7743@shbuild999.sh.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210527130501.GC7743@shbuild999.sh.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 27-05-21 21:05:01, Feng Tang wrote: > On Thu, May 27, 2021 at 09:30:00AM +0200, Michal Hocko wrote: [...] > > Until now this was not a real problem even for OOM context because > > alloc_page_interleave is always used for the interleaving policy > > and that one doesn't use any node mask so the code is not really > > exercised. With your MPOL_PREFERRED this would no longer be the case. > > Given the 'interleave' task may have memory allocated from all nodes, > shouldn't the mempolicy_nodemask_intersects() return true for 'interleave'? > or I'm still missing something? Well, if you go with the renaming then it should be quite obvious that any policies which are not a hard binding should return true. -- Michal Hocko SUSE Labs