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 6BB4F382283 for ; Tue, 26 May 2026 06:38:37 +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=1779777518; cv=none; b=Q+y5zhNNzTJBpp7P9Um/6sSHxYKTQ3kUpVPJ7s21w/byQHimiD5r/O/yk52z0NY3ZbnXRKv84DXZMxKqZz8XGB0BONTxk8g4TpDP27cYIEzAZkn2ucxKuq7S7esSg+HJWH3i2jgVuqhfFzc7z4jgMTPH+vtuxBnC+SXFotP7QG4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779777518; c=relaxed/simple; bh=CaxioxUJ9FXPtxe0BuhQL/CvxhULhorYKlJB4+eUr8Y=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=fTkVbf51tdFUgOymrWdQV3xPjtsnHUfp89okMyXfdypZtZPrG4vmrGlpNUe/ikzVoZvnqn3Go2wzzpnc16+GQkPt2H7j95T9xEge7GYvT0WRuiRu0zgRMrEXAmgzwhHah5WIVfwH7Un9+bcyKRyLwS9DqIa4G+3vmG1N7XWoFf0= 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; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=iMy8o/yy; 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 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="iMy8o/yy" 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 C384A2880; Mon, 25 May 2026 23:38:31 -0700 (PDT) Received: from a080796.blr.arm.com (a080796.arm.com [10.164.21.51]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 337D43F7D8; Mon, 25 May 2026 23:38:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1779777516; bh=CaxioxUJ9FXPtxe0BuhQL/CvxhULhorYKlJB4+eUr8Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iMy8o/yyWJ25zxzQeLC36UXRLe3vh7LSA2jH0VG5IxJWW6PmXQ1tRwePBtqzGTZ96 IJ9CuyATqgUmSwnJgXjVxNLxNYZsU4uaXet0UNRHmHU5Pg7ifsLkUYYdoYYBFIt2nT bxOy6P+U/6wx8AMn5XUozOTBcTeXCGNYuncj6Lh0= From: Dev Jain To: akpm@linux-foundation.org, david@kernel.org, ljs@kernel.org, chrisl@kernel.org, kasong@tencent.com, hughd@google.com, liam@infradead.org Cc: Dev Jain , riel@surriel.com, vbabka@kernel.org, harry@kernel.org, jannh@google.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, qi.zheng@linux.dev, shakeel.butt@linux.dev, baohua@kernel.org, axelrasmussen@google.com, yuanchu@google.com, weixugc@google.com, shikemeng@huaweicloud.com, nphamcs@gmail.com, bhe@redhat.com, youngjun.park@lge.com, baolin.wang@linux.alibaba.com, pfalcato@suse.de, ryan.roberts@arm.com, anshuman.khandual@arm.com Subject: [PATCH v4 10/12] mm/rmap: refactor anon folio unmap in try_to_unmap_one Date: Tue, 26 May 2026 12:06:33 +0530 Message-Id: <20260526063635.61721-11-dev.jain@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260526063635.61721-1-dev.jain@arm.com> References: <20260526063635.61721-1-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 Refactor anonymous folio unmap to ttu_anon_folio. No functional change intended. Signed-off-by: Dev Jain --- mm/rmap.c | 116 ++++++++++++++++++++++++++++++++---------------------- 1 file changed, 68 insertions(+), 48 deletions(-) diff --git a/mm/rmap.c b/mm/rmap.c index c0e385882f562..b1639bad8e27f 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -2136,6 +2136,70 @@ static inline bool ttu_lazyfree_folio(struct vm_area_struct *vma, return true; } +static inline void set_swp_pte_at(struct mm_struct *mm, unsigned long address, + pte_t *ptep, swp_entry_t entry, pte_t pteval, bool anon_exclusive) +{ + pte_t swp_pte = swp_entry_to_pte(entry); + + if (anon_exclusive) + swp_pte = pte_swp_mkexclusive(swp_pte); + + if (likely(pte_present(pteval))) { + if (pte_soft_dirty(pteval)) + swp_pte = pte_swp_mksoft_dirty(swp_pte); + if (pte_uffd_wp(pteval)) + swp_pte = pte_swp_mkuffd_wp(swp_pte); + } else { + /* Device-exclusive entry */ + if (pte_swp_soft_dirty(pteval)) + swp_pte = pte_swp_mksoft_dirty(swp_pte); + if (pte_swp_uffd_wp(pteval)) + swp_pte = pte_swp_mkuffd_wp(swp_pte); + } + + set_pte_at(mm, address, ptep, swp_pte); +} + +static inline bool ttu_anon_folio(struct vm_area_struct *vma, struct folio *folio, + struct page *subpage, unsigned long address, pte_t *ptep, + pte_t pteval) +{ + bool anon_exclusive = folio_test_anon(folio) && PageAnonExclusive(subpage); + swp_entry_t entry = page_swap_entry(subpage); + struct mm_struct *mm = vma->vm_mm; + + if (folio_dup_swap_pages(folio, subpage, 1) < 0) + return false; + + /* + * arch_unmap_one() is expected to be a NOP on + * architectures where we could have PFN swap PTEs, + * so we'll not check/care. + */ + if (arch_unmap_one(mm, vma, address, pteval) < 0) { + folio_put_swap_pages(folio, subpage, 1); + return false; + } + + /* See folio_try_share_anon_rmap(): clear PTE first. */ + if (anon_exclusive && folio_try_share_anon_rmap_pte(folio, subpage)) { + folio_put_swap_pages(folio, subpage, 1); + return false; + } + + if (list_empty(&mm->mmlist)) { + spin_lock(&mmlist_lock); + if (list_empty(&mm->mmlist)) + list_add(&mm->mmlist, &init_mm.mmlist); + spin_unlock(&mmlist_lock); + } + + dec_mm_counter(mm, MM_ANONPAGES); + inc_mm_counter(mm, MM_SWAPENTS); + set_swp_pte_at(mm, address, ptep, entry, pteval, anon_exclusive); + return true; +} + /* * @arg: enum ttu_flags will be passed to this argument */ @@ -2144,7 +2208,7 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, { struct mm_struct *mm = vma->vm_mm; DEFINE_FOLIO_VMA_WALK(pvmw, folio, vma, address, 0); - bool anon_exclusive, ret = true; + bool ret = true; pte_t pteval; struct page *subpage; struct mmu_notifier_range range; @@ -2252,8 +2316,6 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, subpage = folio_page(folio, pfn - folio_pfn(folio)); address = pvmw.address; - anon_exclusive = folio_test_anon(folio) && - PageAnonExclusive(subpage); if (likely(pte_present(pteval))) { nr_pages = folio_unmap_pte_batch(folio, &pvmw, flags, pteval); @@ -2308,8 +2370,6 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, */ dec_mm_counter(mm, mm_counter(folio)); } else if (folio_test_anon(folio)) { - swp_entry_t entry = page_swap_entry(subpage); - pte_t swp_pte; /* * Store the swap location in the pte. * See handle_pte_fault() ... @@ -2331,52 +2391,12 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, goto finish_unmap; } - if (folio_dup_swap_pages(folio, subpage, 1) < 0) { - set_pte_at(mm, address, pvmw.pte, pteval); - goto walk_abort; - } - - /* - * arch_unmap_one() is expected to be a NOP on - * architectures where we could have PFN swap PTEs, - * so we'll not check/care. - */ - if (arch_unmap_one(mm, vma, address, pteval) < 0) { - folio_put_swap_pages(folio, subpage, 1); - set_pte_at(mm, address, pvmw.pte, pteval); - goto walk_abort; - } - - /* See folio_try_share_anon_rmap(): clear PTE first. */ - if (anon_exclusive && - folio_try_share_anon_rmap_pte(folio, subpage)) { - folio_put_swap_pages(folio, subpage, 1); + if (!ttu_anon_folio(vma, folio, subpage, address, + pvmw.pte, pteval)) { set_pte_at(mm, address, pvmw.pte, pteval); goto walk_abort; } - if (list_empty(&mm->mmlist)) { - spin_lock(&mmlist_lock); - if (list_empty(&mm->mmlist)) - list_add(&mm->mmlist, &init_mm.mmlist); - spin_unlock(&mmlist_lock); - } - dec_mm_counter(mm, MM_ANONPAGES); - inc_mm_counter(mm, MM_SWAPENTS); - swp_pte = swp_entry_to_pte(entry); - if (anon_exclusive) - swp_pte = pte_swp_mkexclusive(swp_pte); - if (likely(pte_present(pteval))) { - if (pte_soft_dirty(pteval)) - swp_pte = pte_swp_mksoft_dirty(swp_pte); - if (pte_uffd_wp(pteval)) - swp_pte = pte_swp_mkuffd_wp(swp_pte); - } else { - if (pte_swp_soft_dirty(pteval)) - swp_pte = pte_swp_mksoft_dirty(swp_pte); - if (pte_swp_uffd_wp(pteval)) - swp_pte = pte_swp_mkuffd_wp(swp_pte); - } - set_pte_at(mm, address, pvmw.pte, swp_pte); + goto finish_unmap; } else { /* * This is a locked file-backed folio, -- 2.34.1