Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752053AbaJPJZl (ORCPT ); Thu, 16 Oct 2014 05:25:41 -0400 Received: from mail-wi0-f180.google.com ([209.85.212.180]:61657 "EHLO mail-wi0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751369AbaJPJZi (ORCPT ); Thu, 16 Oct 2014 05:25:38 -0400 Date: Thu, 16 Oct 2014 10:25:30 +0100 From: Steve Capper To: "Aneesh Kumar K.V" Cc: akpm@linux-foundation.org, Andrea Arcangeli , benh@kernel.crashing.org, mpe@ellerman.id.au, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-arch@vger.kernel.org, will.deacon@arm.com, catalin.marinas@arm.com, linux@arm.linux.org.uk Subject: Re: [PATCH 1/2] mm: Update generic gup implementation to handle hugepage directory Message-ID: <20141016092529.GA1524@linaro.org> References: <1413390888-4934-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1413390888-4934-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 15, 2014 at 10:04:47PM +0530, Aneesh Kumar K.V wrote: > Update generic gup implementation with powerpc specific details. > On powerpc at pmd level we can have hugepte, normal pmd pointer > or a pointer to the hugepage directory. > > Signed-off-by: Aneesh Kumar K.V Hi, This patch causes compiler errors on arm and arm64 due to pgd_huge being undefined. I've attached a fixup below, this fixup will require that #define pgd_huge(pgd) 0 be added back into: arch/powerpc/include/asm/page.h For the second patch in this series. Another avenue would be to do something like: #ifndef pgd_huge #define pgd_huge(pgd) (0) #endif Then no changes would be required to arm and arm64 (or other architectures). To help with bisectability, could we please have a suitable fix applied to the two patches in the -mm tree: http://ozlabs.org/~akpm/mmots/broken-out/mm-update-generic-gup-implementation-to-handle-hugepage-directory.patch http://ozlabs.org/~akpm/mmots/broken-out/arch-powerpc-switch-to-generic-rcu-get_user_pages_fast.patch rather than applied afterwards? With pgd_huge(x) defined, this patch passes my futex test on arm (Arndale platform) and arm64(Juno). Cheers, -- Steve >From 2fb7b0308f0aca94c50611257ba82d656abb0768 Mon Sep 17 00:00:00 2001 From: Steve Capper Date: Thu, 16 Oct 2014 09:09:48 +0100 Subject: [PATCH] Fixup for Update generic gup implementation The patch: mm: Update generic gup implementation to handle hugepage directory will not compile for arm or arm64 due to pgd_huge being undefined. Signed-off-by: Steve Capper --- arch/arm/include/asm/pgtable.h | 2 ++ arch/arm64/include/asm/pgtable.h | 2 ++ include/linux/hugetlb.h | 1 - 3 files changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index 90aa4583..46f81fb 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -181,6 +181,8 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* to find an entry in a kernel page-table-directory */ #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) +#define pgd_huge(pgd) (0) + #define pmd_none(pmd) (!pmd_val(pmd)) #define pmd_present(pmd) (pmd_val(pmd)) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 464c5ce..d4462ca 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -462,6 +462,8 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; extern pgd_t idmap_pg_dir[PTRS_PER_PGD]; +#define pgd_huge(pgd) (0) + /* * Encode and decode a swap entry: * bits 0-1: present (must be zero) diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 65e12a2..6e6d338 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -138,7 +138,6 @@ static inline void hugetlb_show_meminfo(void) #define prepare_hugepage_range(file, addr, len) (-EINVAL) #define pmd_huge(x) 0 #define pud_huge(x) 0 -#define pgd_huge(x) 0 #define is_hugepage_only_range(mm, addr, len) 0 #define hugetlb_free_pgd_range(tlb, addr, end, floor, ceiling) ({BUG(); 0; }) #define hugetlb_fault(mm, vma, addr, flags) ({ BUG(); 0; }) -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/