From patchwork Tue Sep 22 06:54:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Huang, Ying" X-Patchwork-Id: 11791621 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5AA011668 for ; Tue, 22 Sep 2020 06:54:38 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id AD07623A32 for ; Tue, 22 Sep 2020 06:54:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AD07623A32 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 9A72D6B009C; Tue, 22 Sep 2020 02:54:36 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 957E56B009D; Tue, 22 Sep 2020 02:54:36 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8707D6B009E; Tue, 22 Sep 2020 02:54:36 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0184.hostedemail.com [216.40.44.184]) by kanga.kvack.org (Postfix) with ESMTP id 704196B009C for ; Tue, 22 Sep 2020 02:54:36 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 3869C8249980 for ; Tue, 22 Sep 2020 06:54:36 +0000 (UTC) X-FDA: 77289784152.08.bone59_0d029442714b Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin08.hostedemail.com (Postfix) with ESMTP id 18DA41819E76F for ; Tue, 22 Sep 2020 06:54:36 +0000 (UTC) X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,ying.huang@intel.com,,RULES_HIT:30054:30064,0,RBL:134.134.136.100:@intel.com:.lbl8.mailshell.net-64.95.201.95 62.18.0.100;04ygwsqg38opap7skqy4t46udgbknopbhu99xmn9mamhi9excc3xqhsm9am5iuk.awf8uyoyh9z615xcixqsfhkztozh54o5drtgpydx9ayfyyqfrodk4cmkuj4tczu.c-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:ft,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:23,LUA_SUMMARY:none X-HE-Tag: bone59_0d029442714b X-Filterd-Recvd-Size: 5156 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by imf18.hostedemail.com (Postfix) with ESMTP for ; Tue, 22 Sep 2020 06:54:34 +0000 (UTC) IronPort-SDR: 3KSSElGTxEWq4JnoR3HP9VZtWYMuSpSxl3dTHmymFhrRbXOxan5s41X7SCNb1ey/3DzCqlMOHS tBqcJvU45UDQ== X-IronPort-AV: E=McAfee;i="6000,8403,9751"; a="224694579" X-IronPort-AV: E=Sophos;i="5.77,289,1596524400"; d="scan'208";a="224694579" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Sep 2020 23:54:33 -0700 IronPort-SDR: uL6ZEh4+QkK4B7jYVcpSqFTt11KDoZHGeimnATf6+7xFTr8WG3QICWTd1zEhfHQ33LDV5UGrNZ F8XxaCiSS9eQ== X-IronPort-AV: E=Sophos;i="5.77,289,1596524400"; d="scan'208";a="485834643" Received: from yhuang-mobile.sh.intel.com ([10.238.4.22]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Sep 2020 23:54:29 -0700 From: Huang Ying To: Peter Zijlstra Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Andrew Morton , Ingo Molnar , Mel Gorman , Rik van Riel , Johannes Weiner , "Matthew Wilcox (Oracle)" , Dave Hansen , Andi Kleen , Michal Hocko , David Rientjes Subject: [RFC -V2] autonuma: Migrate on fault among multiple bound nodes Date: Tue, 22 Sep 2020 14:54:01 +0800 Message-Id: <20200922065401.376348-1-ying.huang@intel.com> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Now, AutoNUMA can only optimize the page placement among the NUMA nodes if the default memory policy is used. Because the memory policy specified explicitly should take precedence. But this seems too strict in some situations. For example, on a system with 4 NUMA nodes, if the memory of an application is bound to the node 0 and 1, AutoNUMA can potentially migrate the pages between the node 0 and 1 to reduce cross-node accessing without breaking the explicit memory binding policy. So in this patch, if mbind(.mode=MPOL_BIND, .flags=MPOL_MF_LAZY) is used to bind the memory of the application to multiple nodes, and in the hint page fault handler both the faulting page node and the accessing node are in the policy nodemask, the page will be tried to be migrated to the accessing node to reduce the cross-node accessing. [Peter Zijlstra: provided the simplified implementation method.] Questions: Sysctl knob kernel.numa_balancing can enable/disable AutoNUMA optimizing globally. But for the memory areas that are bound to multiple NUMA nodes, even if the AutoNUMA is enabled globally via the sysctl knob, we still need to enable AutoNUMA again with a special flag. Why not just optimize the page placement if possible as long as AutoNUMA is enabled globally? The interface would look simpler with that. Signed-off-by: "Huang, Ying" Cc: Andrew Morton Cc: Ingo Molnar Cc: Mel Gorman Cc: Rik van Riel Cc: Johannes Weiner Cc: "Matthew Wilcox (Oracle)" Cc: Dave Hansen Cc: Andi Kleen Cc: Michal Hocko Cc: David Rientjes --- mm/mempolicy.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index eddbe4e56c73..273969204732 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -2494,15 +2494,19 @@ int mpol_misplaced(struct page *page, struct vm_area_struct *vma, unsigned long break; case MPOL_BIND: - /* - * allows binding to multiple nodes. - * use current page if in policy nodemask, - * else select nearest allowed node, if any. - * If no allowed nodes, use current [!misplaced]. + * Allows binding to multiple nodes. If both current and + * accessing nodes are in policy nodemask, migrate to + * accessing node to optimize page placement. Otherwise, + * use current page if in policy nodemask, else select + * nearest allowed node, if any. If no allowed nodes, use + * current [!misplaced]. */ - if (node_isset(curnid, pol->v.nodes)) + if (node_isset(curnid, pol->v.nodes)) { + if (node_isset(thisnid, pol->v.nodes)) + goto moron; goto out; + } z = first_zones_zonelist( node_zonelist(numa_node_id(), GFP_HIGHUSER), gfp_zone(GFP_HIGHUSER), @@ -2516,6 +2520,7 @@ int mpol_misplaced(struct page *page, struct vm_area_struct *vma, unsigned long /* Migrate the page towards the node whose CPU is referencing it */ if (pol->flags & MPOL_F_MORON) { +moron: polnid = thisnid; if (!should_numa_migrate_memory(current, page, curnid, thiscpu))