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=-6.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 04279C433DF for ; Fri, 31 Jul 2020 03:18:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CAC1D207F5 for ; Fri, 31 Jul 2020 03:18:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="bx5OKTEJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731301AbgGaDS4 (ORCPT ); Thu, 30 Jul 2020 23:18:56 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:32738 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1731193AbgGaDSz (ORCPT ); Thu, 30 Jul 2020 23:18:55 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1596165534; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Oeb1VKsxkfGqpmZlCJj7NjGP59zOgyrbLbbbEHSWF0Q=; b=bx5OKTEJ6vZtpE3vKEKJNv2yoWOgop1CdN9RVLp1vF7BK2slVOT0YZyaTKVR6C6cXEX3Ye kox4noBHCyaXhcY8MdqSYjen+sl8xlsS50oIXKfL8FQQDmfzXoKlyqwD3JulebIN75obaZ ZeoyZpoakHQC82IGY9GCvfdGoH9H3kg= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-438-Ho6C2Ek9N0mJD3NRhSS_PQ-1; Thu, 30 Jul 2020 23:18:52 -0400 X-MC-Unique: Ho6C2Ek9N0mJD3NRhSS_PQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4611118839C1; Fri, 31 Jul 2020 03:18:51 +0000 (UTC) Received: from [10.72.13.197] (ovpn-13-197.pek2.redhat.com [10.72.13.197]) by smtp.corp.redhat.com (Postfix) with ESMTP id E61355F7D8; Fri, 31 Jul 2020 03:18:41 +0000 (UTC) Subject: Re: [PATCH V4 0/6] IRQ offloading for vDPA To: Zhu Lingshan , alex.williamson@redhat.com, mst@redhat.com, pbonzini@redhat.com, sean.j.christopherson@intel.com, wanpengli@tencent.com Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org, eli@mellanox.com, shahafs@mellanox.com, parav@mellanox.com References: <20200728042405.17579-1-lingshan.zhu@intel.com> From: Jason Wang Message-ID: Date: Fri, 31 Jul 2020 11:18:40 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200728042405.17579-1-lingshan.zhu@intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 2020/7/28 下午12:23, Zhu Lingshan wrote: > This series intends to implement IRQ offloading for > vhost_vdpa. > > By the feat of irq forwarding facilities like posted > interrupt on X86, irq bypass can help deliver > interrupts to vCPU directly. > > vDPA devices have dedicated hardware backends like VFIO > pass-throughed devices. So it would be possible to setup > irq offloading(irq bypass) for vDPA devices and gain > performance improvements. > > In my testing, with this feature, we can save 0.1ms > in a ping between two VFs on average. > changes from V3: > (1)removed vDPA irq allocate/free helpers in vDPA core. > (2)add a new function get_vq_irq() in struct vdpa_config_ops, > upper layer driver can use this function to: A. query the > irq numbner of a vq. B. detect whether a vq is enabled. > (3)implement get_vq_irq() in ifcvf driver. > (4)in vhost_vdpa, set_status() will setup irq offloading when > setting DRIVER_OK, and unsetup when receive !DRIVER_OK. > (5)minor improvements. Ok, I think you can go ahead to post a V5. It's not bad to start with get_vq_irq() and we can do any changes afterwards if it can work for some cases. Thanks