From patchwork Fri May 24 08:12:12 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 10959279 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 E53301708 for ; Fri, 24 May 2019 08:12:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D6D7B28477 for ; Fri, 24 May 2019 08:12:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CAE3228847; Fri, 24 May 2019 08:12:38 +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=unavailable 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 6B4CF28751 for ; Fri, 24 May 2019 08:12:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389198AbfEXIMc (ORCPT ); Fri, 24 May 2019 04:12:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45272 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389093AbfEXIMb (ORCPT ); Fri, 24 May 2019 04:12:31 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5C814307D851; Fri, 24 May 2019 08:12:31 +0000 (UTC) Received: from hp-dl380pg8-01.lab.eng.pek2.redhat.com (hp-dl380pg8-01.lab.eng.pek2.redhat.com [10.73.8.10]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3C7ED19C4F; Fri, 24 May 2019 08:12:20 +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 Cc: linux-kernel@vger.kernel.org, peterx@redhat.com, James.Bottomley@hansenpartnership.com, hch@infradead.org, davem@davemloft.net, jglisse@redhat.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, christophe.de.dinechin@gmail.com, jrdr.linux@gmail.com Subject: [PATCH net-next 0/6] vhost: accelerate metadata access Date: Fri, 24 May 2019 04:12:12 -0400 Message-Id: <20190524081218.2502-1-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.48]); Fri, 24 May 2019 08:12:31 +0000 (UTC) Sender: linux-parisc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 like SMAP. This is done through setup kernel address through direct mapping and co-opreate VM management with MMU notifiers. Test shows about 23% improvement on TX PPS. TCP_STREAM doesn't see obvious improvement. Thanks Changes from RFC V3: - rebase to net-next - Tweak on the comments Changes from RFC V2: - switch to use direct mapping instead of vmap() - switch to use spinlock + RCU to synchronize MMU notifier and vhost data/control path - set dirty pages in the invalidation callbacks - always use copy_to/from_users() friends for the archs that may need flush_dcache_pages() - various minor fixes Changes from V4: - use invalidate_range() instead of invalidate_range_start() - track dirty pages 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 (6): 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: factor out setting vring addr and num vhost: access vq metadata through kernel virtual address drivers/vhost/net.c | 4 +- drivers/vhost/vhost.c | 850 ++++++++++++++++++++++++++++++++++++------ drivers/vhost/vhost.h | 38 +- 3 files changed, 766 insertions(+), 126 deletions(-)