From patchwork Wed May 24 05:58:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yang Yang X-Patchwork-Id: 98311 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp2629623vqo; Tue, 23 May 2023 23:18:23 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ6f7L3nn+BDzQ9CUmdFjvkg7XPurU/iRWHenKT30jCAdNBUgk77VZicW6hXSSP+hgZxXPAW X-Received: by 2002:a17:90a:8597:b0:24d:f159:d28b with SMTP id m23-20020a17090a859700b0024df159d28bmr15716024pjn.47.1684909102984; Tue, 23 May 2023 23:18:22 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1684909102; cv=none; d=google.com; s=arc-20160816; b=NPO4dsmqNg8w0Wa/Qa/yw40U1bxlK+eVTLwRHwur+7JgvAglH+uEM7P4bkfYelSDHn mIplBUpxkBCz47wVDOXGy08kCf1yZsdP4217Qv1IYcdY76W0iZhK2GMRVcvkRtxqVZJL RoFp3FwTrJAkoxhP3YRVP9FrhhDxYklx52p5tHkZAb4njfCDbDonNvRfuRmSH3Kq3+8w 5W92krJhRZ9WQJdT0qoxNquOHYoGXoveGd6rNMfvgj1jqJThM+upJvfh+vuIQC9pOetd AASiuo8/aM5uKylDSonSdDTjTi0MMD6hHAVbDcEdEjIvBuWgjMdidcFJ6uVBFmqvQ4LW nCKg== 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=S/4R4SuMutEbIKn60YR2+yw3qp0qpoqjLzcR9NS/kyw=; b=XuIcaag7Xp5/qZ7igOsW3sLn9b6cVb3zPOWdSVJCuP8AORoZF+V7JqmyxtNH54ufTd /x7ui5TO8dIiumByznSSwgF6dzy3IUnCrLYBUe7EALx44ECNVxJZrj/2JIyvaOcO/hb7 lYjdUQBPqcPPhL6XShba/ECGnC+dk0sfAtNWhIB5VuDZA3vAL+IEiXkTBk287zoF6ERJ Vdr4ZTLgvTekkXghJNequnZ7vqz+O4IzuISebT8J3sj9BuBeUaYx4L9RUtQVdDj4kxbJ AR0zMXY0d8HIng34HzGYD1qCzdP7kyOBt/dduOKU30iVAqT0cwSCSnSREQGgXVWm4O9W 9w6Q== 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 r5-20020a17090aa08500b0024bc03cfa95si682041pjp.156.2023.05.23.23.18.08; Tue, 23 May 2023 23:18:22 -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 S239557AbjEXF6V (ORCPT + 99 others); Wed, 24 May 2023 01:58:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42096 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239563AbjEXF6T (ORCPT ); Wed, 24 May 2023 01:58:19 -0400 Received: from ubuntu20 (unknown [193.203.214.57]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8DEE1132 for ; Tue, 23 May 2023 22:58:14 -0700 (PDT) Received: by ubuntu20 (Postfix, from userid 1003) id ECE64E1EE6; Wed, 24 May 2023 13:58:02 +0800 (CST) From: Yang Yang To: akpm@linux-foundation.org, david@redhat.com Cc: yang.yang29@zte.com.cn, imbrenda@linux.ibm.com, jiang.xuexin@zte.com.cn, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ran.xiaokai@zte.com.cn, xu.xin.sc@gmail.com, xu.xin16@zte.com.cn Subject: [PATCH v9 3/5] ksm: add ksm zero pages for each process Date: Wed, 24 May 2023 13:58:00 +0800 Message-Id: <20230524055800.20498-1-yang.yang29@zte.com.cn> X-Mailer: git-send-email 2.25.1 In-Reply-To: <202305241351365661923@zte.com.cn> References: <202305241351365661923@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, T_SCC_BODY_TEXT_LINE 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?1766755247355502764?= X-GMAIL-MSGID: =?utf-8?q?1766755247355502764?= 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 Reviewed-by: David Hildenbrand --- fs/proc/base.c | 1 + include/linux/ksm.h | 6 ++++-- include/linux/mm_types.h | 9 +++++++-- mm/khugepaged.c | 2 +- mm/ksm.c | 1 + mm/memory.c | 4 ++-- 6 files changed, 16 insertions(+), 7 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 05452c3b9872..e407a34a46e8 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -3209,6 +3209,7 @@ static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns, seq_printf(m, "ksm_rmap_items %lu\n", mm->ksm_rmap_items); seq_printf(m, "ksm_merging_pages %lu\n", mm->ksm_merging_pages); seq_printf(m, "ksm_process_profit %ld\n", ksm_process_profit(mm)); + seq_printf(m, "ksm_zero_pages %lu\n", mm->ksm_zero_pages); mmput(mm); } diff --git a/include/linux/ksm.h b/include/linux/ksm.h index f2d98c53cfec..0e6f04ac3f2b 100644 --- a/include/linux/ksm.h +++ b/include/linux/ksm.h @@ -35,10 +35,12 @@ void __ksm_exit(struct mm_struct *mm); extern unsigned long ksm_zero_pages; -static inline void ksm_notify_unmap_zero_page(pte_t pte) +static inline void ksm_notify_unmap_zero_page(struct mm_struct *mm, pte_t pte) { - if (is_ksm_zero_pte(pte)) + if (is_ksm_zero_pte(pte)) { ksm_zero_pages--; + mm->ksm_zero_pages--; + } } static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 306a3d1a0fa6..14f781509812 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -777,7 +777,7 @@ 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; /* @@ -785,7 +785,12 @@ struct mm_struct { * including merged and not merged. */ unsigned long ksm_rmap_items; -#endif + /* + * 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 */ #ifdef CONFIG_LRU_GEN struct { /* this mm_struct is on lru_gen_mm_list */ diff --git a/mm/khugepaged.c b/mm/khugepaged.c index e417a928ef8d..85dc2e922f64 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -712,7 +712,7 @@ static void __collapse_huge_page_copy_succeeded(pte_t *pte, spin_lock(ptl); ptep_clear(vma->vm_mm, address, _pte); spin_unlock(ptl); - ksm_notify_unmap_zero_page(pteval); + ksm_notify_unmap_zero_page(vma->vm_mm, pteval); } } else { src_page = pte_page(pteval); diff --git a/mm/ksm.c b/mm/ksm.c index d3ed90159322..07a6fe7d7c99 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -1231,6 +1231,7 @@ static int replace_page(struct vm_area_struct *vma, struct page *page, */ newpte = pte_mkdirty(pte_mkspecial(pfn_pte(page_to_pfn(kpage), vma->vm_page_prot))); ksm_zero_pages++; + mm->ksm_zero_pages++; /* * 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 09c31160af4e..26bb291c1c72 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1416,7 +1416,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, zap_install_uffd_wp_if_needed(vma, addr, pte, details, ptent); if (unlikely(!page)) { - ksm_notify_unmap_zero_page(ptent); + ksm_notify_unmap_zero_page(mm, ptent); continue; } @@ -3122,7 +3122,7 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf) inc_mm_counter(mm, MM_ANONPAGES); } } else { - ksm_notify_unmap_zero_page(vmf->orig_pte); + ksm_notify_unmap_zero_page(mm, vmf->orig_pte); inc_mm_counter(mm, MM_ANONPAGES); } flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte));