From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 107E52E9757 for ; Mon, 8 Sep 2025 07:51:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757317882; cv=none; b=S7fi1WFVBjYIWsDIXagyZGTeeBc6Pbjue8P3bdtd+RB7wLKhRV+Tr538GO1V5NHBJhBJfiMJZlO8Jq0ToKIhgS/THZxYTro/kEIepsTnXSe1msBUot3cFp/jqqTEQdLZfWU1pzR4no3iDdhL3OZfJJdpZD4zgNAcJRvyiW5+H5Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757317882; c=relaxed/simple; bh=QadiF0EnF7f8a8lHvdfm9L18L1obbAQM6Edgr7W8OvU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=rqsbc0+K4brxPaxQumKdxZKTMPxkSVeKDitAc7euafVkI9fG1NKBr/oe27d6ku7RsI56U6OzsuK9QOpBt7dTeNZ9aJ0XlIYfLE2zkGCA4wLKMQscXuhLpxbFthNSZ7ZxFLbhjwHAI9fSA0vKPS9qrNlaM2ghFqdXPwVGaOLVp80= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2880F169C; Mon, 8 Sep 2025 00:51:12 -0700 (PDT) Received: from MacBook-Pro.blr.arm.com (MacBook-Pro.blr.arm.com [10.164.18.52]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 36CB43F63F; Mon, 8 Sep 2025 00:51:15 -0700 (PDT) From: Dev Jain To: akpm@linux-foundation.org, david@redhat.com, kas@kernel.org, willy@infradead.org, hughd@google.com Cc: ziy@nvidia.com, baolin.wang@linux.alibaba.com, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, npache@redhat.com, ryan.roberts@arm.com, baohua@kernel.org, richard.weiyang@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Dev Jain Subject: [PATCH v2 2/2] mm: Drop all references of writable and SCAN_PAGE_RO Date: Mon, 8 Sep 2025 13:20:28 +0530 Message-Id: <20250908075028.38431-3-dev.jain@arm.com> X-Mailer: git-send-email 2.39.5 (Apple Git-154) In-Reply-To: <20250908075028.38431-1-dev.jain@arm.com> References: <20250908075028.38431-1-dev.jain@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Now that all actionable outcomes from checking pte_write() are gone, drop the related references. Acked-by: David Hildenbrand Acked-by: Zi Yan Reviewed-by: Kiryl Shutsemau Reviewed-by: Lorenzo Stoakes Reviewed-by: Baolin Wang Signed-off-by: Dev Jain --- include/trace/events/huge_memory.h | 19 ++++++------------- mm/khugepaged.c | 14 +++----------- 2 files changed, 9 insertions(+), 24 deletions(-) diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h index 2305df6cb485..dd94d14a2427 100644 --- a/include/trace/events/huge_memory.h +++ b/include/trace/events/huge_memory.h @@ -19,7 +19,6 @@ EM( SCAN_PTE_NON_PRESENT, "pte_non_present") \ EM( SCAN_PTE_UFFD_WP, "pte_uffd_wp") \ EM( SCAN_PTE_MAPPED_HUGEPAGE, "pte_mapped_hugepage") \ - EM( SCAN_PAGE_RO, "no_writable_page") \ EM( SCAN_LACK_REFERENCED_PAGE, "lack_referenced_page") \ EM( SCAN_PAGE_NULL, "page_null") \ EM( SCAN_SCAN_ABORT, "scan_aborted") \ @@ -55,15 +54,14 @@ SCAN_STATUS TRACE_EVENT(mm_khugepaged_scan_pmd, - TP_PROTO(struct mm_struct *mm, struct folio *folio, bool writable, + TP_PROTO(struct mm_struct *mm, struct folio *folio, int referenced, int none_or_zero, int status, int unmapped), - TP_ARGS(mm, folio, writable, referenced, none_or_zero, status, unmapped), + TP_ARGS(mm, folio, referenced, none_or_zero, status, unmapped), TP_STRUCT__entry( __field(struct mm_struct *, mm) __field(unsigned long, pfn) - __field(bool, writable) __field(int, referenced) __field(int, none_or_zero) __field(int, status) @@ -73,17 +71,15 @@ TRACE_EVENT(mm_khugepaged_scan_pmd, TP_fast_assign( __entry->mm = mm; __entry->pfn = folio ? folio_pfn(folio) : -1; - __entry->writable = writable; __entry->referenced = referenced; __entry->none_or_zero = none_or_zero; __entry->status = status; __entry->unmapped = unmapped; ), - TP_printk("mm=%p, scan_pfn=0x%lx, writable=%d, referenced=%d, none_or_zero=%d, status=%s, unmapped=%d", + TP_printk("mm=%p, scan_pfn=0x%lx, referenced=%d, none_or_zero=%d, status=%s, unmapped=%d", __entry->mm, __entry->pfn, - __entry->writable, __entry->referenced, __entry->none_or_zero, __print_symbolic(__entry->status, SCAN_STATUS), @@ -117,15 +113,14 @@ TRACE_EVENT(mm_collapse_huge_page, TRACE_EVENT(mm_collapse_huge_page_isolate, TP_PROTO(struct folio *folio, int none_or_zero, - int referenced, bool writable, int status), + int referenced, int status), - TP_ARGS(folio, none_or_zero, referenced, writable, status), + TP_ARGS(folio, none_or_zero, referenced, status), TP_STRUCT__entry( __field(unsigned long, pfn) __field(int, none_or_zero) __field(int, referenced) - __field(bool, writable) __field(int, status) ), @@ -133,15 +128,13 @@ TRACE_EVENT(mm_collapse_huge_page_isolate, __entry->pfn = folio ? folio_pfn(folio) : -1; __entry->none_or_zero = none_or_zero; __entry->referenced = referenced; - __entry->writable = writable; __entry->status = status; ), - TP_printk("scan_pfn=0x%lx, none_or_zero=%d, referenced=%d, writable=%d, status=%s", + TP_printk("scan_pfn=0x%lx, none_or_zero=%d, referenced=%d, status=%s", __entry->pfn, __entry->none_or_zero, __entry->referenced, - __entry->writable, __print_symbolic(__entry->status, SCAN_STATUS)) ); diff --git a/mm/khugepaged.c b/mm/khugepaged.c index a0f1df2a7ae6..af5f5c80fe4e 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -39,7 +39,6 @@ enum scan_result { SCAN_PTE_NON_PRESENT, SCAN_PTE_UFFD_WP, SCAN_PTE_MAPPED_HUGEPAGE, - SCAN_PAGE_RO, SCAN_LACK_REFERENCED_PAGE, SCAN_PAGE_NULL, SCAN_SCAN_ABORT, @@ -557,7 +556,6 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma, struct folio *folio = NULL; pte_t *_pte; int none_or_zero = 0, shared = 0, result = SCAN_FAIL, referenced = 0; - bool writable = false; for (_pte = pte; _pte < pte + HPAGE_PMD_NR; _pte++, address += PAGE_SIZE) { @@ -671,9 +669,6 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma, folio_test_referenced(folio) || mmu_notifier_test_young(vma->vm_mm, address))) referenced++; - - if (pte_write(pteval)) - writable = true; } if (unlikely(cc->is_khugepaged && !referenced)) { @@ -681,13 +676,13 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma, } else { result = SCAN_SUCCEED; trace_mm_collapse_huge_page_isolate(folio, none_or_zero, - referenced, writable, result); + referenced, result); return result; } out: release_pte_pages(pte, _pte, compound_pagelist); trace_mm_collapse_huge_page_isolate(folio, none_or_zero, - referenced, writable, result); + referenced, result); return result; } @@ -1280,7 +1275,6 @@ static int hpage_collapse_scan_pmd(struct mm_struct *mm, unsigned long _address; spinlock_t *ptl; int node = NUMA_NO_NODE, unmapped = 0; - bool writable = false; VM_BUG_ON(address & ~HPAGE_PMD_MASK); @@ -1344,8 +1338,6 @@ static int hpage_collapse_scan_pmd(struct mm_struct *mm, result = SCAN_PTE_UFFD_WP; goto out_unmap; } - if (pte_write(pteval)) - writable = true; page = vm_normal_page(vma, _address, pteval); if (unlikely(!page) || unlikely(is_zone_device_page(page))) { @@ -1435,7 +1427,7 @@ static int hpage_collapse_scan_pmd(struct mm_struct *mm, *mmap_locked = false; } out: - trace_mm_khugepaged_scan_pmd(mm, folio, writable, referenced, + trace_mm_khugepaged_scan_pmd(mm, folio, referenced, none_or_zero, result, unmapped); return result; } -- 2.30.2