From mboxrd@z Thu Jan 1 00:00:00 1970 From: steve.capper@linaro.org (Steve Capper) Date: Fri, 28 Mar 2014 15:01:25 +0000 Subject: [RFC PATCH V4 0/7] get_user_pages_fast for ARM and ARM64 Message-ID: <1396018892-6773-1-git-send-email-steve.capper@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.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