From patchwork Tue Mar 4 15:04:35 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryan Roberts X-Patchwork-Id: 14000955 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E96D3C282D2 for ; Tue, 4 Mar 2025 15:30:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=TF/6uGlm1+JnFATcSTMQMNzWrve0WLCN606nc3w+F2M=; b=PlIqBRAfxPKGKXUvzfWqJ5DOcv aWBWmioQPCEGK8B6OCcpQrF4uDG42aP3CADmZI3iirX/1oTM3wGB8PMAwxdOXRQLSnaE0RZFmtHAm kdJQDSSat/y0Zp7QTQobkHuhtTyH6vjjo5/Kd93jtIX92VDx8M0nJOrUvcxCLGMWSTtiyADX0IfjK 847e6LRseXhZ9DLW7/bJC8EzZWB1BdzQZOyNdOSahYuI6g6Q8jGvzmA9WEtx/R8loaibWB0dhbnyI HyJJstMaz0qyGtEllVkH9T33f99uSKBRRa5ptjb/mgNplPnGekrjHNGZlHVWeHhdowkeU6Xl38eqz uJ5f/XVg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tpUDt-00000005Div-0mMD; Tue, 04 Mar 2025 15:30:21 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tpTpS-000000057Oi-0X5Y for linux-arm-kernel@lists.infradead.org; Tue, 04 Mar 2025 15:05:07 +0000 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 75EFD1C2B; Tue, 4 Mar 2025 07:05:19 -0800 (PST) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.27]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E43683F66E; Tue, 4 Mar 2025 07:05:03 -0800 (PST) From: Ryan Roberts To: Catalin Marinas , Will Deacon , Pasha Tatashin , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , David Hildenbrand , "Matthew Wilcox (Oracle)" , Mark Rutland , Anshuman Khandual , Alexandre Ghiti , Kevin Brodsky Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 05/11] arm64: hugetlb: Use set_ptes_anysz() and ptep_get_and_clear_anysz() Date: Tue, 4 Mar 2025 15:04:35 +0000 Message-ID: <20250304150444.3788920-6-ryan.roberts@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250304150444.3788920-1-ryan.roberts@arm.com> References: <20250304150444.3788920-1-ryan.roberts@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250304_070506_356820_B912F7B8 X-CRM114-Status: GOOD ( 16.46 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Refactor the huge_pte helpers to use the new common set_ptes_anysz() and ptep_get_and_clear_anysz() APIs. This provides 2 benefits; First, when page_table_check=on, hugetlb is now properly/fully checked. Previously only the first page of a hugetlb folio was checked. Second, instead of having to call __set_ptes(nr=1) for each pte in a loop, the whole contiguous batch can now be set in one go, which enables some efficiencies and cleans up the code. One detail to note is that huge_ptep_clear_flush() was previously calling ptep_clear_flush() for a non-contiguous pte (i.e. a pud or pmd block mapping). This has a couple of disadvantages; first ptep_clear_flush() calls ptep_get_and_clear() which transparently handles contpte. Given we only call for non-contiguous ptes, it would be safe, but a waste of effort. It's preferable to go straight to the layer below. However, more problematic is that ptep_get_and_clear() is for PAGE_SIZE entries so it calls page_table_check_pte_clear() and would not clear the whole hugetlb folio. So let's stop special-casing the non-cont case and just rely on get_clear_contig_flush() to do the right thing for non-cont entries. Signed-off-by: Ryan Roberts --- arch/arm64/mm/hugetlbpage.c | 52 +++++++------------------------------ 1 file changed, 10 insertions(+), 42 deletions(-) diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 065be8650aa5..efd18bd1eae3 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -159,12 +159,12 @@ static pte_t get_clear_contig(struct mm_struct *mm, pte_t pte, tmp_pte; bool present; - pte = __ptep_get_and_clear(mm, addr, ptep); + pte = ptep_get_and_clear_anysz(mm, ptep, pgsize); present = pte_present(pte); while (--ncontig) { ptep++; addr += pgsize; - tmp_pte = __ptep_get_and_clear(mm, addr, ptep); + tmp_pte = ptep_get_and_clear_anysz(mm, ptep, pgsize); if (present) { if (pte_dirty(tmp_pte)) pte = pte_mkdirty(pte); @@ -208,7 +208,7 @@ static void clear_flush(struct mm_struct *mm, unsigned long i, saddr = addr; for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) - __ptep_get_and_clear(mm, addr, ptep); + ptep_get_and_clear_anysz(mm, ptep, pgsize); __flush_hugetlb_tlb_range(&vma, saddr, addr, pgsize, true); } @@ -219,32 +219,20 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, size_t pgsize; int i; int ncontig; - unsigned long pfn, dpfn; - pgprot_t hugeprot; ncontig = num_contig_ptes(sz, &pgsize); if (!pte_present(pte)) { for (i = 0; i < ncontig; i++, ptep++, addr += pgsize) - __set_ptes(mm, addr, ptep, pte, 1); + set_ptes_anysz(mm, ptep, pte, 1, pgsize); return; } - if (!pte_cont(pte)) { - __set_ptes(mm, addr, ptep, pte, 1); - return; - } - - pfn = pte_pfn(pte); - dpfn = pgsize >> PAGE_SHIFT; - hugeprot = pte_pgprot(pte); - /* Only need to "break" if transitioning valid -> valid. */ - if (pte_valid(__ptep_get(ptep))) + if (pte_cont(pte) && pte_valid(__ptep_get(ptep))) clear_flush(mm, addr, ptep, pgsize, ncontig); - for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) - __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1); + set_ptes_anysz(mm, ptep, pte, ncontig, pgsize); } pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, @@ -434,11 +422,9 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t pte, int dirty) { - int ncontig, i; + int ncontig; size_t pgsize = 0; - unsigned long pfn = pte_pfn(pte), dpfn; struct mm_struct *mm = vma->vm_mm; - pgprot_t hugeprot; pte_t orig_pte; VM_WARN_ON(!pte_present(pte)); @@ -447,7 +433,6 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma, return __ptep_set_access_flags(vma, addr, ptep, pte, dirty); ncontig = num_contig_ptes(huge_page_size(hstate_vma(vma)), &pgsize); - dpfn = pgsize >> PAGE_SHIFT; if (!__cont_access_flags_changed(ptep, pte, ncontig)) return 0; @@ -462,19 +447,14 @@ int huge_ptep_set_access_flags(struct vm_area_struct *vma, if (pte_young(orig_pte)) pte = pte_mkyoung(pte); - hugeprot = pte_pgprot(pte); - for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) - __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1); - + set_ptes_anysz(mm, ptep, pte, ncontig, pgsize); return 1; } void huge_ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - unsigned long pfn, dpfn; - pgprot_t hugeprot; - int ncontig, i; + int ncontig; size_t pgsize; pte_t pte; @@ -487,16 +467,11 @@ void huge_ptep_set_wrprotect(struct mm_struct *mm, } ncontig = find_num_contig(mm, addr, ptep, &pgsize); - dpfn = pgsize >> PAGE_SHIFT; pte = get_clear_contig_flush(mm, addr, ptep, pgsize, ncontig); pte = pte_wrprotect(pte); - hugeprot = pte_pgprot(pte); - pfn = pte_pfn(pte); - - for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) - __set_ptes(mm, addr, ptep, pfn_pte(pfn, hugeprot), 1); + set_ptes_anysz(mm, ptep, pte, ncontig, pgsize); } pte_t huge_ptep_clear_flush(struct vm_area_struct *vma, @@ -505,13 +480,6 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma, struct mm_struct *mm = vma->vm_mm; size_t pgsize; int ncontig; - pte_t pte; - - pte = __ptep_get(ptep); - VM_WARN_ON(!pte_present(pte)); - - if (!pte_cont(pte)) - return ptep_clear_flush(vma, addr, ptep); ncontig = num_contig_ptes(huge_page_size(hstate_vma(vma)), &pgsize); return get_clear_contig_flush(mm, addr, ptep, pgsize, ncontig);