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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 356E7C43460 for ; Mon, 26 Apr 2021 07:00:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EFE9A6135F for ; Mon, 26 Apr 2021 07:00:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232077AbhDZHA5 (ORCPT ); Mon, 26 Apr 2021 03:00:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59326 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232053AbhDZHAz (ORCPT ); Mon, 26 Apr 2021 03:00:55 -0400 Received: from mail-pf1-x42b.google.com (mail-pf1-x42b.google.com [IPv6:2607:f8b0:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 78F8EC061760 for ; Mon, 26 Apr 2021 00:00:14 -0700 (PDT) Received: by mail-pf1-x42b.google.com with SMTP id c3so19520483pfo.3 for ; Mon, 26 Apr 2021 00:00:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=ZTf4VDhB+vsAlWiKaTvh+bcNfZdV5PiIE39ZO2UyLSc=; b=OzBm0TRrwP0w1UMWiqgYTFsquMLh/ibMx4tparnOh6D5BQP8Vxp5h4x0YzqlDgw/Cx eHFF9TnavfKxRskT7kQ/ZDb08ZSq9/DnjtVv6B9T3C0W1HJhiXenSD7uxwhlSK/707Qg qD4Tdh+ta4TccI/eMNcT5xzXvtMxNciyxefotosU8AiDTbFg7HNkRuEwMcJ/fAy6qo0E dNJJApejzTl0Uisgb6zW6Sv4T9BI3zq10gKu7O/cEHsTpWvZ3jNkBd6QsHw0nCRw5kG9 iEwVnQRM13tQgkthHoqe6Zw6RTnXOLQzipsyIW1R1ViNgWbkDbx5H45cRQVUTdE8FUTT z59Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ZTf4VDhB+vsAlWiKaTvh+bcNfZdV5PiIE39ZO2UyLSc=; b=FfAJmT+knnT1YOYvmxDpjzuGiHCqE2k3THsoVy+gKSqhEycoMMMe4Y1VtqYImXvZWG OQi7gMAV82BKth+D4iez3X7qk7HILAnZ/62bN7gUfqWEChMw/H3eOGrCqe7tTiyVxbR2 b2+EEvvBeH9YnuSqWMLreh1RYeH1LvSOX9e/mwbwMu3aD9Bat67fMvRiJWPnycSoSAml aRk5fgfzLns7i+0k/xXoyI5wmM0i433dx5qCnBem4stSMzKpZIMir29yWhzjBBRU9LrI hKZef1dinOyyj/SOAz2B6trbPPD89l0vxeFkFMafa4pj3t6buSMjI2pocRDTc6T2dowh wgNQ== X-Gm-Message-State: AOAM532GCySo0BDrH9ubRi9Ai95ntCOSA57/Hx/o9oz2G24Gpl6kkZUV g6OLUDQmhNmgXTBCq9dMmex0kA== X-Google-Smtp-Source: ABdhPJwYFD7MUi/5hvdyxTvyf2M6mrOhvBi5WWkars4S6BedJK7btjVTIZiPp+AcQYhNX7AfppHPPA== X-Received: by 2002:a62:194f:0:b029:25c:37cb:2132 with SMTP id 76-20020a62194f0000b029025c37cb2132mr16017661pfz.37.1619420413981; Mon, 26 Apr 2021 00:00:13 -0700 (PDT) Received: from C02DV8HUMD6R.bytedance.net ([139.177.225.224]) by smtp.gmail.com with ESMTPSA id w14sm4535047pfn.3.2021.04.26.00.00.10 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 26 Apr 2021 00:00:13 -0700 (PDT) From: Abel Wu To: akpm@linux-foundation.org, lizefan.x@bytedance.com, tj@kernel.org, hannes@cmpxchg.org, corbet@lwn.net Cc: cgroups@vger.kernel.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Abel Wu Subject: [PATCH 1/3] mm/mempolicy: apply cpuset limits to tasks using default policy Date: Mon, 26 Apr 2021 14:59:44 +0800 Message-Id: <20210426065946.40491-2-wuyun.abel@bytedance.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210426065946.40491-1-wuyun.abel@bytedance.com> References: <20210426065946.40491-1-wuyun.abel@bytedance.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The nodemasks of non-default policies (pol->v) are calculated within the restriction of task->mems_allowed, while default policies are not. This may lead to improper results of mpol_misplaced(), since it can return a target node outside of current->mems_allowed for tasks using default policies. Although this is not a bug because migrating pages to that out-of-cpuset node will fail eventually due to sanity checks in page allocation, it still would be better to avoid such useless efforts. This patch also changes the behavior of autoNUMA a bit by showing a tendency to move pages inside mems_allowed for tasks using default policies, which is good for memory isolation. Signed-off-by: Abel Wu --- mm/mempolicy.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index d79fa299b70c..e0ae6997bbfb 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -2516,7 +2516,10 @@ 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) { - polnid = thisnid; + if (node_isset(thisnid, cpuset_current_mems_allowed)) + polnid = thisnid; + else + polnid = node_random(&cpuset_current_mems_allowed); if (!should_numa_migrate_memory(current, page, curnid, thiscpu)) goto out; -- 2.31.1