From patchwork Fri Oct 8 08:39:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Huang, Ying" X-Patchwork-Id: 12544599 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6ABDC4332F for ; Fri, 8 Oct 2021 08:40:08 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 426396103C for ; Fri, 8 Oct 2021 08:40:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 426396103C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id D5FB26B0074; Fri, 8 Oct 2021 04:40:07 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D0FDA900002; Fri, 8 Oct 2021 04:40:07 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BB0636B0078; Fri, 8 Oct 2021 04:40:07 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0132.hostedemail.com [216.40.44.132]) by kanga.kvack.org (Postfix) with ESMTP id ADA216B0074 for ; Fri, 8 Oct 2021 04:40:07 -0400 (EDT) Received: from smtpin17.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 51929181A3474 for ; Fri, 8 Oct 2021 08:40:07 +0000 (UTC) X-FDA: 78672622854.17.533315A Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by imf23.hostedemail.com (Postfix) with ESMTP id A13D79000382 for ; Fri, 8 Oct 2021 08:40:06 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10130"; a="226752889" X-IronPort-AV: E=Sophos;i="5.85,357,1624345200"; d="scan'208";a="226752889" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Oct 2021 01:40:06 -0700 X-IronPort-AV: E=Sophos;i="5.85,357,1624345200"; d="scan'208";a="439860376" Received: from yhuang6-desk2.sh.intel.com ([10.239.159.119]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Oct 2021 01:40:02 -0700 From: Huang Ying To: linux-kernel@vger.kernel.org Cc: Huang Ying , Dave Hansen , Andrew Morton , Michal Hocko , Rik van Riel , Mel Gorman , Peter Zijlstra , Yang Shi , Zi Yan , Wei Xu , osalvador , Shakeel Butt , linux-mm@kvack.org Subject: [PATCH -V9 3/6] memory tiering: skip to scan fast memory Date: Fri, 8 Oct 2021 16:39:35 +0800 Message-Id: <20211008083938.1702663-4-ying.huang@intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211008083938.1702663-1-ying.huang@intel.com> References: <20211008083938.1702663-1-ying.huang@intel.com> MIME-Version: 1.0 X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: A13D79000382 X-Stat-Signature: 5cggcj3o1foefwfm8tnbcycfsqcjpg5d Authentication-Results: imf23.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf23.hostedemail.com: domain of ying.huang@intel.com has no SPF policy when checking 192.55.52.115) smtp.mailfrom=ying.huang@intel.com X-HE-Tag: 1633682406-947270 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: If the NUMA balancing isn't used to optimize the page placement among sockets but only among memory types, the hot pages in the fast memory node couldn't be migrated (promoted) to anywhere. So it's unnecessary to scan the pages in the fast memory node via changing their PTE/PMD mapping to be PROT_NONE. So that the page faults could be avoided too. In the test, if only the memory tiering NUMA balancing mode is enabled, the number of the NUMA balancing hint faults for the DRAM node is reduced to almost 0 with the patch. While the benchmark score doesn't change visibly. Signed-off-by: "Huang, Ying" Suggested-by: Dave Hansen Cc: Andrew Morton Cc: Michal Hocko Cc: Rik van Riel Cc: Mel Gorman Cc: Peter Zijlstra Cc: Yang Shi Cc: Zi Yan Cc: Wei Xu Cc: osalvador Cc: Shakeel Butt Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org --- mm/huge_memory.c | 30 +++++++++++++++++++++--------- mm/mprotect.c | 13 ++++++++++++- 2 files changed, 33 insertions(+), 10 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 5e9ef0fc261e..8edcd64b5b1f 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #include @@ -1766,17 +1767,28 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, } #endif - /* - * Avoid trapping faults against the zero page. The read-only - * data is likely to be read-cached on the local CPU and - * local/remote hits to the zero page are not interesting. - */ - if (prot_numa && is_huge_zero_pmd(*pmd)) - goto unlock; + if (prot_numa) { + struct page *page; + /* + * Avoid trapping faults against the zero page. The read-only + * data is likely to be read-cached on the local CPU and + * local/remote hits to the zero page are not interesting. + */ + if (is_huge_zero_pmd(*pmd)) + goto unlock; - if (prot_numa && pmd_protnone(*pmd)) - goto unlock; + if (pmd_protnone(*pmd)) + goto unlock; + page = pmd_page(*pmd); + /* + * Skip scanning top tier node if normal numa + * balancing is disabled + */ + if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_NORMAL) && + node_is_toptier(page_to_nid(page))) + goto unlock; + } /* * In case prot_numa, we are under mmap_read_lock(mm). It's critical * to not clear pmd intermittently to avoid race with MADV_DONTNEED diff --git a/mm/mprotect.c b/mm/mprotect.c index 883e2cc85cad..0dd3f82ec6eb 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include #include @@ -83,6 +84,7 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, */ if (prot_numa) { struct page *page; + int nid; /* Avoid TLB flush if possible */ if (pte_protnone(oldpte)) @@ -109,7 +111,16 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, * Don't mess with PTEs if page is already on the node * a single-threaded process is running on. */ - if (target_node == page_to_nid(page)) + nid = page_to_nid(page); + if (target_node == nid) + continue; + + /* + * Skip scanning top tier node if normal numa + * balancing is disabled + */ + if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_NORMAL) && + node_is_toptier(nid)) continue; }