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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 06ABEC43387 for ; Fri, 28 Dec 2018 07:55:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C82D5205C9 for ; Fri, 28 Dec 2018 07:55:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731818AbeL1Hzq (ORCPT ); Fri, 28 Dec 2018 02:55:46 -0500 Received: from mx1.redhat.com ([209.132.183.28]:35874 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729300AbeL1Hzp (ORCPT ); Fri, 28 Dec 2018 02:55:45 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6687F7DD06; Fri, 28 Dec 2018 07:55:45 +0000 (UTC) Received: from jason-ThinkPad-T450s.redhat.com (ovpn-12-196.pek2.redhat.com [10.72.12.196]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1C91C5D9C9; Fri, 28 Dec 2018 07:55:39 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH V2 0/3] vhost: accelerate metadata access through vmap() Date: Fri, 28 Dec 2018 15:55:34 +0800 Message-Id: <20181228075537.21402-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 28 Dec 2018 07:55:45 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi: This series tries to access virtqueue metadata through kernel virtual address instead of copy_user() friends since they had too much overheads like checks, spec barriers or even hardware feature toggling. Test shows about 24% improvement on TX PPS. It should benefit other cases as well. Changes from V1: - instead of pinning pages, use MMU notifier to invalidate vmaps and remap duing metadata prefetch - fix build warning on MIPS Please review Jason Wang (3): vhost: generalize adding used elem vhost: fine grain userspace memory accessors vhost: access vq metadata through kernel virtual address drivers/vhost/net.c | 4 +- drivers/vhost/vhost.c | 362 ++++++++++++++++++++++++++++++++++++++---- drivers/vhost/vhost.h | 15 +- 3 files changed, 348 insertions(+), 33 deletions(-) -- 2.17.1