From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f175.google.com (mail-wi0-f175.google.com [209.85.212.175]) by kanga.kvack.org (Postfix) with ESMTP id EA47D8299E for ; Tue, 6 May 2014 11:30:26 -0400 (EDT) Received: by mail-wi0-f175.google.com with SMTP id f8so3715230wiw.8 for ; Tue, 06 May 2014 08:30:25 -0700 (PDT) Received: from mail-wi0-f173.google.com (mail-wi0-f173.google.com [209.85.212.173]) by mx.google.com with ESMTPS id sg12si4647849wic.23.2014.05.06.08.30.24 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 06 May 2014 08:30:24 -0700 (PDT) Received: by mail-wi0-f173.google.com with SMTP id bs8so7515201wib.0 for ; Tue, 06 May 2014 08:30:24 -0700 (PDT) From: Steve Capper Subject: [RFC PATCH V5 0/6] get_user_pages_fast for ARM and ARM64 Date: Tue, 6 May 2014 16:30:03 +0100 Message-Id: <1399390209-1756-1-git-send-email-steve.capper@linaro.org> Sender: owner-linux-mm@kvack.org List-ID: To: linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, linux@arm.linux.org.uk, linux-arch@vger.kernel.org, linux-mm@kvack.org Cc: will.deacon@arm.com, gary.robertson@linaro.org, christoffer.dall@linaro.org, peterz@infradead.org, anders.roxell@linaro.org, akpm@linux-foundation.org, Steve Capper 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 V4 are: * corrected the arm64 logic so it now correctly rcu-frees page table backing pages. * rcu free logic relaxed for pre-ARMv7 ARM as we need an IPI to invalidate TLBs anyway. * rebased to 3.15-rc3 (some minor changes were needed to allow it to merge). * dropped Catalin's mmu_gather patch as that's been merged already. I would really appreciate any comments (especially on the validity or otherwise of the core fast_gup implementation) and/or testers. Cheers, -- Steve 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 | 8 +- arch/arm64/include/asm/tlb.h | 18 ++- arch/arm64/mm/flush.c | 19 +++ mm/Kconfig | 3 + mm/Makefile | 1 + mm/gup.c | 297 ++++++++++++++++++++++++++++++++++ 13 files changed, 424 insertions(+), 9 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