From patchwork Mon May 22 14:39:52 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Punit Agrawal X-Patchwork-Id: 9740755 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 600C86034C for ; Mon, 22 May 2017 15:27:24 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4D12528470 for ; Mon, 22 May 2017 15:27:24 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4036128709; Mon, 22 May 2017 15:27:24 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 9B31F28470 for ; Mon, 22 May 2017 15:27:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=BdMR76x2H7BARaSdyQ3krW3/MowiJDNtT37HBDXtJ5Y=; b=mhqdIKNo89nUJ9w1h96tcsba7/ CUOF0e8VS+pP8sRgn+BM6ngxpAsSCOS4aEVZtILclXZID6rbVEoLqDUoYsIlOXliTkeKj/QowxqKp srWH8AT+N7mYaRPoW4hDGBnA49FX5CMkPPna3H7rgkXQu6QJLE+9GtLzTFM0vNun7xq70YQ8XLaMD ZAiLRhcsLsPXqPvwq3Eujqh9WZ9tv0MFD7V7n/j10YnfG40Ek2i3uEiMc3eR6cxewxoWim2cWZ/uO C2HbM9uFK1HJRWX2407TIDhhItoSoQyYnSvCmdy1x0AN47HS4OrMDiARHMilOHehibys74+gaQvSg M+diUYmA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1dCpEv-00028D-3X; Mon, 22 May 2017 15:27:21 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1dCoWF-00031t-Tr for linux-arm-kernel@lists.infradead.org; Mon, 22 May 2017 14:41:14 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E5619164F; Mon, 22 May 2017 07:40:55 -0700 (PDT) Received: from localhost (e105922-lin.cambridge.arm.com [10.1.207.56]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B42643F53D; Mon, 22 May 2017 07:40:55 -0700 (PDT) From: Punit Agrawal To: will.deacon@arm.com, catalin.marinas@arm.com Subject: [PATCH v3 05/11] arm64: hugetlb: Spring clean huge pte accessors Date: Mon, 22 May 2017 15:39:52 +0100 Message-Id: <20170522143958.12867-7-punit.agrawal@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170522143958.12867-1-punit.agrawal@arm.com> References: <20170522143958.12867-1-punit.agrawal@arm.com> X-ARM-No-Footer: FoSSMail X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170522_074112_073388_9DB698D3 X-CRM114-Status: GOOD ( 12.87 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, David Woods , Punit Agrawal , linux-arm-kernel@lists.infradead.org, Steve Capper MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Steve Capper This patch aims to re-structure the huge pte accessors without affecting their functionality. Control flow is changed to reduce indentation and expanded use is made of post for loop variable modification. It is then much easier to add break-before-make semantics in a subsequent patch. Cc: David Woods Signed-off-by: Steve Capper Signed-off-by: Punit Agrawal Reviewed-by: Mark Rutland --- arch/arm64/mm/hugetlbpage.c | 119 ++++++++++++++++++++------------------------ 1 file changed, 54 insertions(+), 65 deletions(-) diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index cb84ca33bc6b..08deed7c71f0 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -74,7 +74,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, size_t pgsize; int i; int ncontig; - unsigned long pfn; + unsigned long pfn, dpfn; pgprot_t hugeprot; /* @@ -90,14 +90,13 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, ncontig = find_num_contig(mm, addr, ptep, &pgsize); pfn = pte_pfn(pte); + dpfn = pgsize >> PAGE_SHIFT; hugeprot = pte_pgprot(pte); - for (i = 0; i < ncontig; i++) { + + for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) { pr_debug("%s: set pte %p to 0x%llx\n", __func__, ptep, pte_val(pfn_pte(pfn, hugeprot))); set_pte_at(mm, addr, ptep, pfn_pte(pfn, hugeprot)); - ptep++; - pfn += pgsize >> PAGE_SHIFT; - addr += pgsize; } } @@ -195,91 +194,81 @@ pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma, pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - pte_t pte; - - if (pte_cont(*ptep)) { - int ncontig, i; - size_t pgsize; - bool is_dirty = false; - - ncontig = find_num_contig(mm, addr, ptep, &pgsize); - /* save the 1st pte to return */ - pte = ptep_get_and_clear(mm, addr, ptep); - for (i = 1, addr += pgsize; i < ncontig; ++i, addr += pgsize) { - /* - * If HW_AFDBM is enabled, then the HW could - * turn on the dirty bit for any of the page - * in the set, so check them all. - */ - ++ptep; - if (pte_dirty(ptep_get_and_clear(mm, addr, ptep))) - is_dirty = true; - } - if (is_dirty) - return pte_mkdirty(pte); - else - return pte; - } else { + int ncontig, i; + size_t pgsize; + pte_t orig_pte = huge_ptep_get(ptep); + + if (!pte_cont(orig_pte)) return ptep_get_and_clear(mm, addr, ptep); + + ncontig = find_num_contig(mm, addr, ptep, &pgsize); + for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) { + /* + * If HW_AFDBM is enabled, then the HW could + * turn on the dirty bit for any of the page + * in the set, so check them all. + */ + if (pte_dirty(ptep_get_and_clear(mm, addr, ptep))) + orig_pte = pte_mkdirty(orig_pte); } + + return orig_pte; } int huge_ptep_set_access_flags(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep, pte_t pte, int dirty) { - if (pte_cont(pte)) { - int ncontig, i, changed = 0; - size_t pgsize = 0; - unsigned long pfn = pte_pfn(pte); - /* Select all bits except the pfn */ - pgprot_t hugeprot = pte_pgprot(pte); - - pfn = pte_pfn(pte); - ncontig = find_num_contig(vma->vm_mm, addr, ptep, - &pgsize); - for (i = 0; i < ncontig; ++i, ++ptep, addr += pgsize) { - changed |= ptep_set_access_flags(vma, addr, ptep, - pfn_pte(pfn, - hugeprot), - dirty); - pfn += pgsize >> PAGE_SHIFT; - } - return changed; - } else { + int ncontig, i, changed = 0; + size_t pgsize = 0; + unsigned long pfn = pte_pfn(pte), dpfn; + pgprot_t hugeprot; + + if (!pte_cont(pte)) return ptep_set_access_flags(vma, addr, ptep, pte, dirty); + + ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize); + dpfn = pgsize >> PAGE_SHIFT; + hugeprot = pte_pgprot(pte); + + for (i = 0; i < ncontig; i++, ptep++, addr += pgsize, pfn += dpfn) { + changed |= ptep_set_access_flags(vma, addr, ptep, + pfn_pte(pfn, hugeprot), dirty); } + + return changed; } void huge_ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { - if (pte_cont(*ptep)) { - int ncontig, i; - size_t pgsize = 0; + int ncontig, i; + size_t pgsize; - ncontig = find_num_contig(mm, addr, ptep, &pgsize); - for (i = 0; i < ncontig; ++i, ++ptep, addr += pgsize) - ptep_set_wrprotect(mm, addr, ptep); - } else { + if (!pte_cont(*ptep)) { ptep_set_wrprotect(mm, addr, ptep); + return; } + + ncontig = find_num_contig(mm, addr, ptep, &pgsize); + for (i = 0; i < ncontig; i++, ptep++, addr += pgsize) + ptep_set_wrprotect(mm, addr, ptep); } void huge_ptep_clear_flush(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep) { - if (pte_cont(*ptep)) { - int ncontig, i; - size_t pgsize = 0; - - ncontig = find_num_contig(vma->vm_mm, addr, ptep, - &pgsize); - for (i = 0; i < ncontig; ++i, ++ptep, addr += pgsize) - ptep_clear_flush(vma, addr, ptep); - } else { + int ncontig, i; + size_t pgsize; + + if (!pte_cont(*ptep)) { ptep_clear_flush(vma, addr, ptep); + return; } + + ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize); + for (i = 0; i < ncontig; i++, ptep++, addr += pgsize) + ptep_clear_flush(vma, addr, ptep); } static __init int setup_hugepagesz(char *opt)