From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3426EC43381 for ; Thu, 21 Mar 2019 16:36:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0EDA921917 for ; Thu, 21 Mar 2019 16:36:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728621AbfCUQgl (ORCPT ); Thu, 21 Mar 2019 12:36:41 -0400 Received: from foss.arm.com ([217.140.101.70]:59346 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728528AbfCUQgl (ORCPT ); Thu, 21 Mar 2019 12:36:41 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AD5D2374; Thu, 21 Mar 2019 09:36:40 -0700 (PDT) Received: from e108454-lin.cambridge.arm.com (e108454-lin.cambridge.arm.com [10.1.196.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BB88D3F614; Thu, 21 Mar 2019 09:36:38 -0700 (PDT) From: Julien Grall To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Cc: christoffer.dall@arm.com, james.morse@arm.com, marc.zyngier@arm.com, julien.thierry@arm.com, suzuki.poulose@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, Julien Grall Subject: [PATCH RFC 00/14] kvm/arm: Align the VMID allocation with the arm64 ASID one Date: Thu, 21 Mar 2019 16:36:09 +0000 Message-Id: <20190321163623.20219-1-julien.grall@arm.com> X-Mailer: git-send-email 2.11.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch series is moving out the ASID allocator in a separate file in order to re-use it for the VMID. The benefits are: - CPUs are not forced to exit a roll-over. - Context invalidation is now per-CPU rather than broadcasted. There are no performance regression on the fastpath for ASID allocation. Actually on the hackbench measurement (300 hackbench) it was .7% faster. The measurement was made on a Seattle based SoC (8 CPUs), with the number of VMID limited to 4-bit. The test involves running concurrently 40 guests with 2 vCPUs. Each guest will then execute hackbench 5 times before exiting. The performance difference between the current algo and the new one are: - 2.5% less exit from the guest - 22.4% more flush, although they are now local rather than broadcasted - 0.11% faster (just for the record) The ASID allocator rework to make it generic has been divided in multiple patches to make the review easier. A branch with the patch based on 5.1-rc1 can be found: http://xenbits.xen.org/gitweb/?p=people/julieng/linux-arm.git;a=shortlog;h=refs/heads/vmid-rework/rfc Cheers, Julien Grall (14): arm64/mm: Introduce asid_info structure and move asid_generation/asid_map to it arm64/mm: Move active_asids and reserved_asids to asid_info arm64/mm: Move bits to asid_info arm64/mm: Move the variable lock and tlb_flush_pending to asid_info arm64/mm: Remove dependency on MM in new_context arm64/mm: Store the number of asid allocated per context arm64/mm: Introduce NUM_ASIDS arm64/mm: Split asid_inits in 2 parts arm64/mm: Split the function check_and_switch_context in 3 parts arm64/mm: Introduce a callback to flush the local context arm64: Move the ASID allocator code in a separate file arm64/lib: asid: Allow user to update the context under the lock arm/kvm: Introduce a new VMID allocator kvm/arm: Align the VMID allocation with the arm64 ASID one arch/arm/include/asm/kvm_asid.h | 81 +++++++++++++++ arch/arm/include/asm/kvm_asm.h | 2 +- arch/arm/include/asm/kvm_host.h | 5 +- arch/arm/include/asm/kvm_hyp.h | 1 + arch/arm/kvm/Makefile | 1 + arch/arm/kvm/asid.c | 191 +++++++++++++++++++++++++++++++++++ arch/arm/kvm/hyp/tlb.c | 8 +- arch/arm64/include/asm/asid.h | 81 +++++++++++++++ arch/arm64/include/asm/kvm_asid.h | 8 ++ arch/arm64/include/asm/kvm_asm.h | 2 +- arch/arm64/include/asm/kvm_host.h | 5 +- arch/arm64/kvm/hyp/tlb.c | 10 +- arch/arm64/lib/Makefile | 2 + arch/arm64/lib/asid.c | 191 +++++++++++++++++++++++++++++++++++ arch/arm64/mm/context.c | 205 ++++++-------------------------------- virt/kvm/arm/arm.c | 112 +++++++-------------- 16 files changed, 638 insertions(+), 267 deletions(-) create mode 100644 arch/arm/include/asm/kvm_asid.h create mode 100644 arch/arm/kvm/asid.c create mode 100644 arch/arm64/include/asm/asid.h create mode 100644 arch/arm64/include/asm/kvm_asid.h create mode 100644 arch/arm64/lib/asid.c -- 2.11.0