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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham 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 A26D7C433E1 for ; Mon, 25 May 2020 02:53:06 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6BB432075F for ; Mon, 25 May 2020 02:53:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6BB432075F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id B5C2580007; Sun, 24 May 2020 22:53:04 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 99A6F80011; Sun, 24 May 2020 22:53:04 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7A06780010; Sun, 24 May 2020 22:53:04 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0022.hostedemail.com [216.40.44.22]) by kanga.kvack.org (Postfix) with ESMTP id 5C6B38000E for ; Sun, 24 May 2020 22:53:04 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 11794180AD81D for ; Mon, 25 May 2020 02:53:04 +0000 (UTC) X-FDA: 76853719488.10.idea76_1a94cadf6d535 X-HE-Tag: idea76_1a94cadf6d535 X-Filterd-Recvd-Size: 5727 Received: from loongson.cn (mail.loongson.cn [114.242.206.163]) by imf44.hostedemail.com (Postfix) with ESMTP for ; Mon, 25 May 2020 02:53:02 +0000 (UTC) Received: from kvm-dev1.localdomain (unknown [10.2.5.134]) by mail.loongson.cn (Coremail) with SMTP id AQAAf9Dxj974MsteoL84AA--.426S4; Mon, 25 May 2020 10:52:41 +0800 (CST) From: Bibo Mao To: Thomas Bogendoerfer , Jiaxun Yang , Huacai Chen , Andrew Morton , Paul Burton , Dmitry Korotin , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Stafford Horne , Steven Price , Anshuman Khandual Cc: linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, Mike Rapoport , Sergei Shtylyov , "Maciej W. Rozycki" , linux-mm@kvack.org, David Hildenbrand Subject: [PATCH v6 3/4] mm/memory.c: Add memory read privilege on page fault handling Date: Mon, 25 May 2020 10:52:39 +0800 Message-Id: <1590375160-6997-3-git-send-email-maobibo@loongson.cn> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1590375160-6997-1-git-send-email-maobibo@loongson.cn> References: <1590375160-6997-1-git-send-email-maobibo@loongson.cn> X-CM-TRANSID:AQAAf9Dxj974MsteoL84AA--.426S4 X-Coremail-Antispam: 1UD129KBjvJXoWxZFy5KF13KF15tryDWF47CFg_yoW5AFy7pF Z7Cw1F9rsrXw10yFWfCFn29r1ruw4rKFW5urySka4ku3ZxJr15Wrs7GayFvrykJFWkK3Wr Gr4jqr4UZayIvaUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPqb7Iv0xC_Kw4lb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I2 0VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI 8067AKxVWUXwA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF 64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW5JVW7JwA2z4x0Y4vE2Ix0cI8IcV CY1x0267AKxVWxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280 aVCY1x0267AKxVW8Jr0_Cr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64 kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm 72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI 1lc2xSY4AK6svPMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E 5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZV WrXwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY 1x0267AKxVWxJVW8Jr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14 v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x 07b5wZcUUUUU= X-CM-SenderInfo: xpdruxter6z05rqj20fqof0/ 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: Here add pte_sw_mkyoung function to make page readable on MIPS platform during page fault handling. This patch improves page fault latency about 10% on my MIPS machine with lmbench lat_pagefault case. It is noop function on other arches, there is no negative influence on those architectures. Signed-off-by: Bibo Mao --- arch/mips/include/asm/pgtable.h | 2 ++ include/asm-generic/pgtable.h | 16 ++++++++++++++++ mm/memory.c | 3 +++ 3 files changed, 21 insertions(+) diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h index d2004b5..0743087 100644 --- a/arch/mips/include/asm/pgtable.h +++ b/arch/mips/include/asm/pgtable.h @@ -414,6 +414,8 @@ static inline pte_t pte_mkyoung(pte_t pte) return pte; } +#define pte_sw_mkyoung pte_mkyoung + #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT static inline int pte_huge(pte_t pte) { return pte_val(pte) & _PAGE_HUGE; } diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index fa5c73f..b5278ec 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -244,6 +244,22 @@ static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addres } #endif +/* + * On some architectures hardware does not set page access bit when accessing + * memory page, it is responsibilty of software setting this bit. It brings + * out extra page fault penalty to track page access bit. For optimization page + * access bit can be set during all page fault flow on these arches. + * To be differentiate with macro pte_mkyoung, this macro is used on platforms + * where software maintains page access bit. + */ +#ifndef pte_sw_mkyoung +static inline pte_t pte_sw_mkyoung(pte_t pte) +{ + return pte; +} +#define pte_sw_mkyoung pte_sw_mkyoung +#endif + #ifndef pte_savedwrite #define pte_savedwrite pte_write #endif diff --git a/mm/memory.c b/mm/memory.c index 8bb31c4..c7c8960 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2704,6 +2704,7 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf) } flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte)); entry = mk_pte(new_page, vma->vm_page_prot); + entry = pte_sw_mkyoung(entry); entry = maybe_mkwrite(pte_mkdirty(entry), vma); /* * Clear the pte entry and flush it first, before updating the @@ -3378,6 +3379,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) __SetPageUptodate(page); entry = mk_pte(page, vma->vm_page_prot); + entry = pte_sw_mkyoung(entry); if (vma->vm_flags & VM_WRITE) entry = pte_mkwrite(pte_mkdirty(entry)); @@ -3660,6 +3662,7 @@ vm_fault_t alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg, flush_icache_page(vma, page); entry = mk_pte(page, vma->vm_page_prot); + entry = pte_sw_mkyoung(entry); if (write) entry = maybe_mkwrite(pte_mkdirty(entry), vma); /* copy-on-write page */ -- 1.8.3.1