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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2B142C3063F for ; Mon, 3 Jul 2023 17:39:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230218AbjGCRjE (ORCPT ); Mon, 3 Jul 2023 13:39:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230334AbjGCRjE (ORCPT ); Mon, 3 Jul 2023 13:39:04 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D43DDE5E for ; Mon, 3 Jul 2023 10:39:02 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6AB6B60FF4 for ; Mon, 3 Jul 2023 17:39:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C02DAC433C7; Mon, 3 Jul 2023 17:39:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1688405941; bh=TjIH353stjTdnTt8zYj7lR06zC1ukMYDUj6gnjdoAw4=; h=Date:To:From:Subject:From; b=nULTVPT4JqKddxBHM/r5aU3I/CbyOzkmqw6XDJ2sTD42KSo3a6IuB4ChzSrasDV9u p+/NCsudruuNG3bHh3hikz8MqDTJH6APicxYsxrkMWiTIU/Bj1+5a0oCyArmWXA8V1 1K4C1yQEoanH6r3TYsj/A225Le0OGE+TULubvKMo= Date: Mon, 03 Jul 2023 10:39:01 -0700 To: mm-commits@vger.kernel.org, yang.yang29@zte.com.cn, ran.xiaokai@zte.com.cn, jiang.xuexin@zte.com.cn, imbrenda@linux.ibm.com, david@redhat.com, xu.xin16@zte.com.cn, akpm@linux-foundation.org From: Andrew Morton Subject: + ksm-add-ksm-zero-pages-for-each-process.patch added to mm-unstable branch Message-Id: <20230703173901.C02DAC433C7@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: ksm: add ksm zero pages for each process has been added to the -mm mm-unstable branch. Its filename is ksm-add-ksm-zero-pages-for-each-process.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/ksm-add-ksm-zero-pages-for-each-process.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: xu xin Subject: ksm: add ksm zero pages for each process Date: Tue, 13 Jun 2023 11:09:38 +0800 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. Link: https://lkml.kernel.org/r/20230613030938.185993-1-yang.yang29@zte.com.cn Signed-off-by: xu xin Acked-by: David Hildenbrand Reviewed-by: Xiaokai Ran Reviewed-by: Yang Yang Cc: Claudio Imbrenda Cc: Xuexin Jiang Signed-off-by: Andrew Morton --- fs/proc/base.c | 1 + include/linux/ksm.h | 8 +++++--- include/linux/mm_types.h | 9 +++++++-- mm/khugepaged.c | 2 +- mm/ksm.c | 1 + mm/memory.c | 4 ++-- 6 files changed, 17 insertions(+), 8 deletions(-) --- a/fs/proc/base.c~ksm-add-ksm-zero-pages-for-each-process +++ a/fs/proc/base.c @@ -3207,6 +3207,7 @@ static int proc_pid_ksm_stat(struct seq_ mm = get_task_mm(task); if (mm) { seq_printf(m, "ksm_rmap_items %lu\n", mm->ksm_rmap_items); + seq_printf(m, "ksm_zero_pages %lu\n", mm->ksm_zero_pages); seq_printf(m, "ksm_merging_pages %lu\n", mm->ksm_merging_pages); seq_printf(m, "ksm_process_profit %ld\n", ksm_process_profit(mm)); mmput(mm); --- a/include/linux/ksm.h~ksm-add-ksm-zero-pages-for-each-process +++ a/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_might_unmap_zero_page(pte_t pte) +static inline void ksm_might_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) @@ -109,7 +111,7 @@ static inline void ksm_exit(struct mm_st { } -static inline void ksm_might_unmap_zero_page(pte_t pte) +static inline void ksm_might_unmap_zero_page(struct mm_struct *mm, pte_t pte) { } --- a/include/linux/mm_types.h~ksm-add-ksm-zero-pages-for-each-process +++ a/include/linux/mm_types.h @@ -784,7 +784,7 @@ 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; /* @@ -792,7 +792,12 @@ 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 */ --- a/mm/khugepaged.c~ksm-add-ksm-zero-pages-for-each-process +++ a/mm/khugepaged.c @@ -710,7 +710,7 @@ static void __collapse_huge_page_copy_su spin_lock(ptl); ptep_clear(vma->vm_mm, address, _pte); spin_unlock(ptl); - ksm_might_unmap_zero_page(pteval); + ksm_might_unmap_zero_page(vma->vm_mm, pteval); } } else { src_page = pte_page(pteval); --- a/mm/ksm.c~ksm-add-ksm-zero-pages-for-each-process +++ a/mm/ksm.c @@ -1233,6 +1233,7 @@ static int replace_page(struct vm_area_s */ 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 --- a/mm/memory.c~ksm-add-ksm-zero-pages-for-each-process +++ a/mm/memory.c @@ -1434,7 +1434,7 @@ static unsigned long zap_pte_range(struc zap_install_uffd_wp_if_needed(vma, addr, pte, details, ptent); if (unlikely(!page)) { - ksm_might_unmap_zero_page(ptent); + ksm_might_unmap_zero_page(mm, ptent); continue; } @@ -3133,7 +3133,7 @@ static vm_fault_t wp_page_copy(struct vm inc_mm_counter(mm, MM_ANONPAGES); } } else { - ksm_might_unmap_zero_page(vmf->orig_pte); + ksm_might_unmap_zero_page(mm, vmf->orig_pte); inc_mm_counter(mm, MM_ANONPAGES); } flush_cache_page(vma, vmf->address, pte_pfn(vmf->orig_pte)); _ Patches currently in -mm which might be from xu.xin16@zte.com.cn are ksm-support-unsharing-ksm-placed-zero-pages.patch ksm-count-all-zero-pages-placed-by-ksm.patch ksm-add-ksm-zero-pages-for-each-process.patch ksm-consider-ksm-placed-zeropages-when-calculating-ksm-profit.patch selftest-add-a-testcase-of-ksm-zero-pages.patch