From patchwork Thu Apr 13 05:55:47 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Yang X-Patchwork-Id: 82810 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp816112vqo; Wed, 12 Apr 2023 23:08:14 -0700 (PDT) X-Google-Smtp-Source: AKy350biWPwg4xwTofzHb77ivkhFjoWSOAPx0mmYGnbNnjPDneg7rQGVcf6ASJBHnAbNEkmrtZBx X-Received: by 2002:a17:906:8e8e:b0:93e:5baa:d443 with SMTP id ru14-20020a1709068e8e00b0093e5baad443mr1410590ejc.63.1681366094425; Wed, 12 Apr 2023 23:08:14 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681366094; cv=none; d=google.com; s=arc-20160816; b=QMY1pNMN7P0H74IQQCc7SMhM9elCPM/bCIc32DLOGaX+vN+3/R/xuHZAbeQwIR3UsQ LDANpXhkzfakVy/dbzcMrVBsbI0ZeoUw7pZuH/CW2+nO/Tm+yOZ7KrXZPtN8xHIDLsD1 vUscjVjrWtl55wjFDlyckzpUildKb/O75yX38xZKzL54khtmQ/Slnymf57hx5oXB3zst dlNy1l+RnV6xEvdhud8W/51fmS9WVCkCL/3SxJBAfcAwGehYgLPb2tG8pvybKWkHS4Iy XxtHLFCI8f+TeME0VcWniyPzQBnBBk5xJT4E8fY6ou1aXy2Tql05cYEvhk0+wHyj8sIs cuYQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from; bh=EnvkglYHBJSNxolnmJ+r1pMBc7+CeHtCs4VLYzfPDgM=; b=xN18uXcBd+ZJWZW+2D0UD1cNNTdcpZ0eqlhZ21fO4iRDgCga0Bq1kOwtrGiVF3C+/Z w4HTCeYeyXTh7t54RaJ+h2HrjtJKvJyR8fHjQMx3akGieMC146qHXCAhOQj+NE9nLCoS 9ZpA6qLOOwZqPTx/11prKZI0mZikoCwhfjc/b9id+GtkmVZVoOjwlW5F9ayHuHKPyzEM fELoK27st/WSnqmr7ztC5MbeONcYa6PgBvMemUrUyff8+WOO5P2YhyHQfxcqdFshIPJc PQRcxtPUMaAcGl6RarlaCJVku5UKJvzPknFP8qKPsxRJOxjoaBmlkO+mk7Dk+fVXxJkq zkkQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=zte.com.cn Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id mz11-20020a1709071b8b00b0092bfbe8e4adsi874271ejc.238.2023.04.12.23.07.49; Wed, 12 Apr 2023 23:08:14 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=zte.com.cn Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229928AbjDMFzz (ORCPT + 99 others); Thu, 13 Apr 2023 01:55:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55110 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229689AbjDMFzy (ORCPT ); Thu, 13 Apr 2023 01:55:54 -0400 Received: from ubuntu20 (unknown [193.203.214.57]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 024864ED8 for ; Wed, 12 Apr 2023 22:55:52 -0700 (PDT) Received: by ubuntu20 (Postfix, from userid 1003) id AE1D7E196E; Thu, 13 Apr 2023 05:55:51 +0000 (UTC) From: Yang Yang To: akpm@linux-foundation.org, david@redhat.com Cc: yang.yang29@zte.com.cn, imbrenda@linux.ibm.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ran.xiaokai@zte.com.cn, xu.xin.sc@gmail.com, xu.xin16@zte.com.cn, Xuexin Jiang Subject: [PATCH v7 3/6] ksm: add ksm zero pages for each process Date: Thu, 13 Apr 2023 13:55:47 +0800 Message-Id: <20230413055547.181107-1-yang.yang29@zte.com.cn> X-Mailer: git-send-email 2.25.1 In-Reply-To: <202304131346489021903@zte.com.cn> References: <202304131346489021903@zte.com.cn> MIME-Version: 1.0 X-Spam-Status: No, score=3.4 required=5.0 tests=BAYES_00, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,FSL_HELO_NON_FQDN_1, HEADER_FROM_DIFFERENT_DOMAINS,HELO_NO_DOMAIN,NO_DNS_FOR_FROM, RCVD_IN_PBL,RDNS_NONE,SPF_SOFTFAIL,SPOOFED_FREEMAIL_NO_RDNS autolearn=no autolearn_force=no version=3.4.6 X-Spam-Level: *** X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1763040133854192974?= X-GMAIL-MSGID: =?utf-8?q?1763040133854192974?= From: xu xin As the number of ksm zero pages is not included in ksm_merging_pages per process when enabling use_zero_pages, it's unclear of how many actual pages are merged by KSM. To let users accurately estimate their memory demands when unsharing KSM zero-pages, it's necessary to show KSM zero- pages per process. In addition, it help users to know the actual KSM profit because KSM-placed zero pages are also benefit from KSM. since unsharing zero pages placed by KSM accurately is achieved, then tracking empty pages merging and unmerging is not a difficult thing any longer. Since we already have /proc//ksm_stat, just add the information of 'ksm_zero_pages' in it. Signed-off-by: xu xin Cc: Claudio Imbrenda Cc: David Hildenbrand Cc: Xuexin Jiang Cc: Xiaokai Ran Cc: Yang Yang --- fs/proc/base.c | 3 +++ include/linux/ksm.h | 10 ++++++---- include/linux/mm_types.h | 11 +++++++++-- mm/ksm.c | 2 +- mm/memory.c | 4 ++-- 5 files changed, 21 insertions(+), 9 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index ab9fa5b1b6be..235182cd143d 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -3211,6 +3211,9 @@ static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns, seq_printf(m, "ksm_merging_pages %lu\n", mm->ksm_merging_pages); seq_printf(m, "ksm_merge_type %s\n", ksm_merge_type(mm)); seq_printf(m, "ksm_process_profit %ld\n", ksm_process_profit(mm)); +#ifdef CONFIG_KSM_ZERO_PAGES_TRACK + seq_printf(m, "ksm_zero_pages %lu\n", mm->ksm_zero_pages); +#endif mmput(mm); } diff --git a/include/linux/ksm.h b/include/linux/ksm.h index ea628d2a9105..2da40af9ad4d 100644 --- a/include/linux/ksm.h +++ b/include/linux/ksm.h @@ -100,22 +100,24 @@ static inline void folio_migrate_ksm(struct folio *newfolio, struct folio *old) #define set_pte_ksm_zero(pte) pte_mkdirty(pte_mkspecial(pte)) #define is_ksm_zero_pte(pte) (is_zero_pfn(pte_pfn(pte)) && pte_dirty(pte)) extern unsigned long ksm_zero_pages; -static inline void inc_ksm_zero_pages(void) +static inline void inc_ksm_zero_pages(struct mm_struct *mm) { ksm_zero_pages++; + mm->ksm_zero_pages++; } -static inline void dec_ksm_zero_pages(void) +static inline void dec_ksm_zero_pages(struct mm_struct *mm) { ksm_zero_pages--; + mm->ksm_zero_pages--; } #else /* !CONFIG_KSM_ZERO_PAGES_TRACK */ #define set_pte_ksm_zero(pte) pte_mkspecial(pte) #define is_ksm_zero_pte(pte) 0 -static inline void inc_ksm_zero_pages(void) +static inline void inc_ksm_zero_pages(struct mm_struct *mm) { } -static inline void dec_ksm_zero_pages(void) +static inline void dec_ksm_zero_pages(struct mm_struct *mm) { } #endif /* CONFIG_KSM_ZERO_PAGES_TRACK */ diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 3fc9e680f174..2e72329ed1a2 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -766,7 +766,7 @@ struct mm_struct { #ifdef CONFIG_KSM /* * Represent how many pages of this process are involved in KSM - * merging. + * merging (not including ksm_zero_pages). */ unsigned long ksm_merging_pages; /* @@ -774,7 +774,14 @@ struct mm_struct { * including merged and not merged. */ unsigned long ksm_rmap_items; -#endif +#ifdef CONFIG_KSM_ZERO_PAGES_TRACK + /* + * Represent how many empty pages are merged with kernel zero + * pages when enabling KSM use_zero_pages. + */ + unsigned long ksm_zero_pages; +#endif /* CONFIG_KSM_ZERO_PAGES_TRACK */ +#endif /* CONFIG_KSM */ #ifdef CONFIG_LRU_GEN struct { /* this mm_struct is on lru_gen_mm_list */ diff --git a/mm/ksm.c b/mm/ksm.c index 232680393741..7867fae3c61c 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -1248,7 +1248,7 @@ static int replace_page(struct vm_area_struct *vma, struct page *page, } else { newpte = set_pte_ksm_zero(pfn_pte(page_to_pfn(kpage), vma->vm_page_prot)); - inc_ksm_zero_pages(); + inc_ksm_zero_pages(mm); /* * We're replacing an anonymous page with a zero page, which is * not anonymous. We need to do proper accounting otherwise we diff --git a/mm/memory.c b/mm/memory.c index 76598287280f..ec89b81a14fd 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1418,7 +1418,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, ptent); if (unlikely(!page)) { if (is_ksm_zero_pte(ptent)) - dec_ksm_zero_pages(); + dec_ksm_zero_pages(mm); continue; } @@ -3122,7 +3122,7 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf) } } else { if (is_ksm_zero_pte(vmf->orig_pte)) - dec_ksm_zero_pages(); + dec_ksm_zero_pages(mm); inc_mm_counter(mm, MM_ANONPAGES); } flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte));