From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve Capper Subject: [RFC PATCH V4 0/7] get_user_pages_fast for ARM and ARM64 Date: Fri, 28 Mar 2014 15:01:25 +0000 Message-ID: <1396018892-6773-1-git-send-email-steve.capper@linaro.org> Return-path: Sender: owner-linux-mm@kvack.org To: linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, linux@arm.linux.org.uk, linux-mm@kvack.org, linux-arch@vger.kernel.org Cc: peterz@infradead.org, gary.robertson@linaro.org, anders.roxell@linaro.org, akpm@linux-foundation.org, Steve Capper List-Id: linux-arch.vger.kernel.org Hello, This RFC series implements get_user_pages_fast and __get_user_pages_fast. These are required for Transparent HugePages to function correctly, as a futex on a THP tail will otherwise result in an infinite loop (due to the core implementation of __get_user_pages_fast always returning 0). This series may also be beneficial for direct-IO heavy workloads and certain KVM workloads. The main changes since RFC V3 are: * fast_gup now generalised and moved to core code. * pte_special logic now extended to reduce unnecessary icache syncs. * dropped the pte_accessible logic in fast_gup as it is unnecessary. I would really appreciate any comments (especially on the validity or otherwise of the core fast_gup implementation) and/or testers. Cheers, -- Steve Catalin Marinas (1): arm64: Convert asm/tlb.h to generic mmu_gather Steve Capper (6): mm: Introduce a general RCU get_user_pages_fast. arm: mm: Introduce special ptes for LPAE arm: mm: Enable HAVE_RCU_TABLE_FREE logic arm: mm: Enable RCU fast_gup arm64: mm: Enable HAVE_RCU_TABLE_FREE logic arm64: mm: Enable RCU fast_gup arch/arm/Kconfig | 4 + arch/arm/include/asm/pgtable-2level.h | 2 + arch/arm/include/asm/pgtable-3level.h | 14 ++ arch/arm/include/asm/pgtable.h | 6 +- arch/arm/include/asm/tlb.h | 38 ++++- arch/arm/mm/flush.c | 19 +++ arch/arm64/Kconfig | 4 + arch/arm64/include/asm/pgtable.h | 4 + arch/arm64/include/asm/tlb.h | 140 +++------------- arch/arm64/mm/flush.c | 19 +++ mm/Kconfig | 3 + mm/Makefile | 1 + mm/gup.c | 297 ++++++++++++++++++++++++++++++++++ 13 files changed, 431 insertions(+), 120 deletions(-) create mode 100644 mm/gup.c -- 1.8.1.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f171.google.com ([209.85.212.171]:33534 "EHLO mail-wi0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751340AbaC1PBl (ORCPT ); Fri, 28 Mar 2014 11:01:41 -0400 Received: by mail-wi0-f171.google.com with SMTP id q5so843834wiv.16 for ; Fri, 28 Mar 2014 08:01:39 -0700 (PDT) From: Steve Capper Subject: [RFC PATCH V4 0/7] get_user_pages_fast for ARM and ARM64 Date: Fri, 28 Mar 2014 15:01:25 +0000 Message-ID: <1396018892-6773-1-git-send-email-steve.capper@linaro.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, linux@arm.linux.org.uk, linux-mm@kvack.org, linux-arch@vger.kernel.org Cc: peterz@infradead.org, gary.robertson@linaro.org, anders.roxell@linaro.org, akpm@linux-foundation.org, Steve Capper Message-ID: <20140328150125.XsXV22mTc0lm3AQ4DKGcc1kbJBhrOMBh3tyMuFQf8eU@z> Hello, This RFC series implements get_user_pages_fast and __get_user_pages_fast. These are required for Transparent HugePages to function correctly, as a futex on a THP tail will otherwise result in an infinite loop (due to the core implementation of __get_user_pages_fast always returning 0). This series may also be beneficial for direct-IO heavy workloads and certain KVM workloads. The main changes since RFC V3 are: * fast_gup now generalised and moved to core code. * pte_special logic now extended to reduce unnecessary icache syncs. * dropped the pte_accessible logic in fast_gup as it is unnecessary. I would really appreciate any comments (especially on the validity or otherwise of the core fast_gup implementation) and/or testers. Cheers, -- Steve Catalin Marinas (1): arm64: Convert asm/tlb.h to generic mmu_gather Steve Capper (6): mm: Introduce a general RCU get_user_pages_fast. arm: mm: Introduce special ptes for LPAE arm: mm: Enable HAVE_RCU_TABLE_FREE logic arm: mm: Enable RCU fast_gup arm64: mm: Enable HAVE_RCU_TABLE_FREE logic arm64: mm: Enable RCU fast_gup arch/arm/Kconfig | 4 + arch/arm/include/asm/pgtable-2level.h | 2 + arch/arm/include/asm/pgtable-3level.h | 14 ++ arch/arm/include/asm/pgtable.h | 6 +- arch/arm/include/asm/tlb.h | 38 ++++- arch/arm/mm/flush.c | 19 +++ arch/arm64/Kconfig | 4 + arch/arm64/include/asm/pgtable.h | 4 + arch/arm64/include/asm/tlb.h | 140 +++------------- arch/arm64/mm/flush.c | 19 +++ mm/Kconfig | 3 + mm/Makefile | 1 + mm/gup.c | 297 ++++++++++++++++++++++++++++++++++ 13 files changed, 431 insertions(+), 120 deletions(-) create mode 100644 mm/gup.c -- 1.8.1.4