From patchwork Wed Jan 23 09:55:52 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 10776903 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2D5A5746 for ; Wed, 23 Jan 2019 09:56:55 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1E1352AC14 for ; Wed, 23 Jan 2019 09:56:55 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0FDA22B440; Wed, 23 Jan 2019 09:56:55 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B7E0E2AC14 for ; Wed, 23 Jan 2019 09:56:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727185AbfAWJ4G (ORCPT ); Wed, 23 Jan 2019 04:56:06 -0500 Received: from mx1.redhat.com ([209.132.183.28]:46222 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726804AbfAWJ4F (ORCPT ); Wed, 23 Jan 2019 04:56:05 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C95AD89ACB; Wed, 23 Jan 2019 09:56:05 +0000 (UTC) Received: from jason-ThinkPad-T450s.redhat.com (ovpn-12-89.pek2.redhat.com [10.72.12.89]) by smtp.corp.redhat.com (Postfix) with ESMTP id 549CB60168; Wed, 23 Jan 2019 09:55:59 +0000 (UTC) From: Jason Wang To: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, jasowang@redhat.com Cc: mst@redhat.com, kvm@vger.kernel.org Subject: [PATCH net-next V4 0/5] vhost: accelerate metadata access through vmap() Date: Wed, 23 Jan 2019 17:55:52 +0800 Message-Id: <20190123095557.30168-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Wed, 23 Jan 2019 09:56:05 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 V3: - don't try to use vmap for file backed pages - rebase to master Changes from V2: - fix buggy range overlapping check - tear down MMU notifier during vhost ioctl to make sure invalidation request can read metadata userspace address and vq size without holding vq mutex. Changes from V1: - instead of pinning pages, use MMU notifier to invalidate vmaps and remap duing metadata prefetch - fix build warning on MIPS Jason Wang (5): vhost: generalize adding used elem vhost: fine grain userspace memory accessors vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch() vhost: introduce helpers to get the size of metadata area vhost: access vq metadata through kernel virtual address drivers/vhost/net.c | 4 +- drivers/vhost/vhost.c | 441 +++++++++++++++++++++++++++++++++++++----- drivers/vhost/vhost.h | 15 +- mm/shmem.c | 1 + 4 files changed, 410 insertions(+), 51 deletions(-)