From patchwork Tue Apr 30 16:30:41 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steve Capper X-Patchwork-Id: 2505641 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) by patchwork1.kernel.org (Postfix) with ESMTP id D46AC3FD85 for ; Tue, 30 Apr 2013 16:33:06 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UXDTb-000749-8z; Tue, 30 Apr 2013 16:32:23 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UXDTJ-0005vF-91; Tue, 30 Apr 2013 16:32:05 +0000 Received: from mail-wi0-x230.google.com ([2a00:1450:400c:c05::230]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1UXDSh-0005lC-PP for linux-arm-kernel@lists.infradead.org; Tue, 30 Apr 2013 16:31:31 +0000 Received: by mail-wi0-f176.google.com with SMTP id hi8so1882910wib.9 for ; Tue, 30 Apr 2013 09:31:06 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-received:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references:x-gm-message-state; bh=N8njnOU8fllHFwN4blNrX1M01wnHh7hlBXOLeIoLDTA=; b=F2ajZU0GoucrPk+p6p8Fd7k494WuLWzINvb57aZZtkLNG42gPl9NVfXXALHtHCtwJf JQcYr9bHg3y9lKgvCCj7pcm8M9OSEox1tSF8R4eqLAoHQiPERnlYGXOgLIm5XBjJwOPt 3EViwVGo2mB1UKb1jpRo0Kg3M2b8v35X6lz0QInpYL1HfxChHAFLuAm6fEgFX4yg8OV6 /tOGGILlpbvWNLddVGUCPRClA3BuSjzhflLWzYvzUyA8hloMZJXnZ5XXbPbLF9QdTRst eKktVBkDDnDlOcmqER+GPktdj6zXTh/e43w+5FySv8JHJll2fBTypLrzMxA0PAgkpZ8W x6CQ== X-Received: by 10.180.72.227 with SMTP id g3mr24665676wiv.1.1367339465262; Tue, 30 Apr 2013 09:31:05 -0700 (PDT) Received: from localhost.localdomain (marmot.wormnet.eu. [188.246.204.87]) by mx.google.com with ESMTPSA id k5sm30044708wiy.5.2013.04.30.09.31.04 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Tue, 30 Apr 2013 09:31:04 -0700 (PDT) From: Steve Capper To: linux-mm@kvack.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [RFC PATCH 2/9] x86: mm: Remove x86 version of huge_pmd_share. Date: Tue, 30 Apr 2013 17:30:41 +0100 Message-Id: <1367339448-21727-3-git-send-email-steve.capper@linaro.org> X-Mailer: git-send-email 1.7.2.5 In-Reply-To: <1367339448-21727-1-git-send-email-steve.capper@linaro.org> References: <1367339448-21727-1-git-send-email-steve.capper@linaro.org> X-Gm-Message-State: ALoCoQnbvXh2LkQHlCvhVbqqcTMCCbyYRfcS4Fe+L7Ghz//1cL3Embib7/TG91LDuaa0ByznDgKd X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130430_123128_105110_6A950E55 X-CRM114-Status: GOOD ( 18.17 ) X-Spam-Score: -1.9 (-) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-1.9 points) pts rule name description ---- ---------------------- -------------------------------------------------- -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Cc: Steve Capper , Catalin Marinas , Will Deacon , Michal Hocko , Ken Chen , Mel Gorman X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org The huge_pmd_share code has been copied over to mm/hugetlb.c to make it accessible to other architectures. Remove the x86 copy of the huge_pmd_share code and enable the ARCH_WANT_HUGE_PMD_SHARE config flag. That way we reference the general one. Signed-off-by: Steve Capper --- arch/x86/Kconfig | 3 ++ arch/x86/mm/hugetlbpage.c | 120 ---------------------------------------------- 2 files changed, 3 insertions(+), 120 deletions(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 70c0f3d..60e3c402 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -212,6 +212,9 @@ config ARCH_HIBERNATION_POSSIBLE config ARCH_SUSPEND_POSSIBLE def_bool y +config ARCH_WANT_HUGE_PMD_SHARE + def_bool y + config ZONE_DMA32 bool default X86_64 diff --git a/arch/x86/mm/hugetlbpage.c b/arch/x86/mm/hugetlbpage.c index ae1aa71..7e522a3 100644 --- a/arch/x86/mm/hugetlbpage.c +++ b/arch/x86/mm/hugetlbpage.c @@ -16,126 +16,6 @@ #include #include -static unsigned long page_table_shareable(struct vm_area_struct *svma, - struct vm_area_struct *vma, - unsigned long addr, pgoff_t idx) -{ - unsigned long saddr = ((idx - svma->vm_pgoff) << PAGE_SHIFT) + - svma->vm_start; - unsigned long sbase = saddr & PUD_MASK; - unsigned long s_end = sbase + PUD_SIZE; - - /* Allow segments to share if only one is marked locked */ - unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED; - unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED; - - /* - * match the virtual addresses, permission and the alignment of the - * page table page. - */ - if (pmd_index(addr) != pmd_index(saddr) || - vm_flags != svm_flags || - sbase < svma->vm_start || svma->vm_end < s_end) - return 0; - - return saddr; -} - -static int vma_shareable(struct vm_area_struct *vma, unsigned long addr) -{ - unsigned long base = addr & PUD_MASK; - unsigned long end = base + PUD_SIZE; - - /* - * check on proper vm_flags and page table alignment - */ - if (vma->vm_flags & VM_MAYSHARE && - vma->vm_start <= base && end <= vma->vm_end) - return 1; - return 0; -} - -/* - * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() - * and returns the corresponding pte. While this is not necessary for the - * !shared pmd case because we can allocate the pmd later as well, it makes the - * code much cleaner. pmd allocation is essential for the shared case because - * pud has to be populated inside the same i_mmap_mutex section - otherwise - * racing tasks could either miss the sharing (see huge_pte_offset) or select a - * bad pmd for sharing. - */ -static pte_t * -huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) -{ - struct vm_area_struct *vma = find_vma(mm, addr); - struct address_space *mapping = vma->vm_file->f_mapping; - pgoff_t idx = ((addr - vma->vm_start) >> PAGE_SHIFT) + - vma->vm_pgoff; - struct vm_area_struct *svma; - unsigned long saddr; - pte_t *spte = NULL; - pte_t *pte; - - if (!vma_shareable(vma, addr)) - return (pte_t *)pmd_alloc(mm, pud, addr); - - mutex_lock(&mapping->i_mmap_mutex); - vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) { - if (svma == vma) - continue; - - saddr = page_table_shareable(svma, vma, addr, idx); - if (saddr) { - spte = huge_pte_offset(svma->vm_mm, saddr); - if (spte) { - get_page(virt_to_page(spte)); - break; - } - } - } - - if (!spte) - goto out; - - spin_lock(&mm->page_table_lock); - if (pud_none(*pud)) - pud_populate(mm, pud, (pmd_t *)((unsigned long)spte & PAGE_MASK)); - else - put_page(virt_to_page(spte)); - spin_unlock(&mm->page_table_lock); -out: - pte = (pte_t *)pmd_alloc(mm, pud, addr); - mutex_unlock(&mapping->i_mmap_mutex); - return pte; -} - -/* - * unmap huge page backed by shared pte. - * - * Hugetlb pte page is ref counted at the time of mapping. If pte is shared - * indicated by page_count > 1, unmap is achieved by clearing pud and - * decrementing the ref count. If count == 1, the pte page is not shared. - * - * called with vma->vm_mm->page_table_lock held. - * - * returns: 1 successfully unmapped a shared pte page - * 0 the underlying pte page is not shared, or it is the last user - */ -int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep) -{ - pgd_t *pgd = pgd_offset(mm, *addr); - pud_t *pud = pud_offset(pgd, *addr); - - BUG_ON(page_count(virt_to_page(ptep)) == 0); - if (page_count(virt_to_page(ptep)) == 1) - return 0; - - pud_clear(pud); - put_page(virt_to_page(ptep)); - *addr = ALIGN(*addr, HPAGE_SIZE * PTRS_PER_PTE) - HPAGE_SIZE; - return 1; -} - pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr, unsigned long sz) {