From patchwork Tue Nov 16 01:35:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Huang, Ying" X-Patchwork-Id: 12621039 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 35F3EC4332F for ; Tue, 16 Nov 2021 01:36:26 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C942261929 for ; Tue, 16 Nov 2021 01:36:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org C942261929 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 0FC146B00B3; Mon, 15 Nov 2021 20:36:24 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 01A676B00B7; Mon, 15 Nov 2021 20:36:23 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D525D6B00B5; Mon, 15 Nov 2021 20:36:23 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0036.hostedemail.com [216.40.44.36]) by kanga.kvack.org (Postfix) with ESMTP id BB4266B00B4 for ; Mon, 15 Nov 2021 20:36:23 -0500 (EST) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 76C4D779B3 for ; Tue, 16 Nov 2021 01:36:23 +0000 (UTC) X-FDA: 78813078204.27.27AC4E8 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by imf31.hostedemail.com (Postfix) with ESMTP id EA41C105264E for ; Tue, 16 Nov 2021 01:36:03 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10169"; a="233433888" X-IronPort-AV: E=Sophos;i="5.87,237,1631602800"; d="scan'208";a="233433888" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Nov 2021 17:36:19 -0800 X-IronPort-AV: E=Sophos;i="5.87,237,1631602800"; d="scan'208";a="454262524" Received: from yhuang6-desk2.sh.intel.com ([10.239.159.101]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Nov 2021 17:36:07 -0800 From: Huang Ying To: Peter Zijlstra , Mel Gorman Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Feng Tang , Huang Ying , Dave Hansen , Andrew Morton , Michal Hocko , Rik van Riel , Yang Shi , Zi Yan , Wei Xu , osalvador , Shakeel Butt Subject: [PATCH -V10 3/6] memory tiering: skip to scan fast memory Date: Tue, 16 Nov 2021 09:35:19 +0800 Message-Id: <20211116013522.140575-4-ying.huang@intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211116013522.140575-1-ying.huang@intel.com> References: <20211116013522.140575-1-ying.huang@intel.com> MIME-Version: 1.0 X-Stat-Signature: gogdrwo6stoh4czdim45nfytgfxyus8q Authentication-Results: imf31.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf31.hostedemail.com: domain of ying.huang@intel.com has no SPF policy when checking 134.134.136.24) smtp.mailfrom=ying.huang@intel.com X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: EA41C105264E X-HE-Tag: 1637026563-993610 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 e5483347291c..cab8048eb779 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 e552f5e0ccbd..ddc24ca52b12 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; }