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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 870AFC4361B for ; Thu, 4 Mar 2021 08:59:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 704BE64F18 for ; Thu, 4 Mar 2021 08:59:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237184AbhCDI7O (ORCPT ); Thu, 4 Mar 2021 03:59:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47940 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237142AbhCDI6y (ORCPT ); Thu, 4 Mar 2021 03:58:54 -0500 Received: from mail-ed1-x52a.google.com (mail-ed1-x52a.google.com [IPv6:2a00:1450:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 86923C061756 for ; Thu, 4 Mar 2021 00:58:39 -0800 (PST) Received: by mail-ed1-x52a.google.com with SMTP id d13so28699122edp.4 for ; Thu, 04 Mar 2021 00:58:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=WcsXXXbrDSVn9JnL1kI4tSiyWOxm9D+WqcuRuZ8ZPPY=; b=SgIJQX+v/dAp6zKtCoUdKvxd747j/oIsOOlWt3BXoINpvb8gM2GUvlCR5DCRqwiLzx qanElF3lR5Fr1/bcxvlAMjAdzVuPop19Ck5lylT/XrIhZ3r2rle5OmJX8PxYEU9XKxuu Iw6L1WE502mtn0lYP9httAirkVvwVutnvdqLR0+0sBBVZsjZd2vA/zVcYpTZI5p/MXAR +tsVCNpQxU53RtJ4KyP79ztx2eVInM9T5VemFzBVpaRDtn5ogkX3Y6iMsEL6on25AwGM QzTayVrZ5DCL6nhyaK0As2yq9bQ2XY7aGG4uM3iZbe2E67jW4p4yj4D7UlTLfDhQXcNl Au8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=WcsXXXbrDSVn9JnL1kI4tSiyWOxm9D+WqcuRuZ8ZPPY=; b=M1opbV6zMPK2NSU79m1SNY3BzpD7Qb6L5PSDQixxkVE4MLZgrD9qtLeRPbYlX4V4x4 sZBvIzDTWJbAsoSbwQKnMahKdhtvJMjz5O3f3FpugLLw3ebtKnEmtXd75yv5glzzG3wN x3yZES4ofx8YJJf2jxoYDJ1vXUS2aKJDnyhahUEhpEe2eq6KC2wgtN2I089Wt5u9bF15 I+8iduiWMnXyKUB8n8IOHsV2yqDnroEHiSg9Ksgh9fpEVLDF/87uDZiYdDfZOO2j47Bx KOEHPWpxPknVOfeNVvtB+c5DF5wM0XSMYVrxpHhjGSM1bB2f04iUrOZUYbh+VqU2hN3Y /Gzw== X-Gm-Message-State: AOAM531Y37BZV/1SdDE5gwOaC7j2WBym8jN4o0egYohOVlxRNF2QzcPH M5odV+WoIA6dyasfGsFMUH55H1MxPDByGTQZS7n8 X-Google-Smtp-Source: ABdhPJz1yhS4bpogbrj7802vVThEsweuzWygoO16SS4Sm5PZ+sHcuk5hH2T4ZXUpPr/tI/5DOjViugXNCjqXBngk2S0= X-Received: by 2002:a05:6402:6ca:: with SMTP id n10mr3201074edy.312.1614848318350; Thu, 04 Mar 2021 00:58:38 -0800 (PST) MIME-Version: 1.0 References: <20210223115048.435-1-xieyongji@bytedance.com> <20210223115048.435-11-xieyongji@bytedance.com> In-Reply-To: From: Yongji Xie Date: Thu, 4 Mar 2021 16:58:27 +0800 Message-ID: Subject: Re: Re: [RFC v4 10/11] vduse: Introduce a workqueue for irq injection To: Jason Wang Cc: "Michael S. Tsirkin" , Stefan Hajnoczi , Stefano Garzarella , Parav Pandit , Bob Liu , Christoph Hellwig , Randy Dunlap , Matthew Wilcox , viro@zeniv.linux.org.uk, Jens Axboe , bcrl@kvack.org, Jonathan Corbet , virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org, linux-aio@kvack.org, linux-fsdevel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Mar 4, 2021 at 2:59 PM Jason Wang wrote: > > > On 2021/2/23 7:50 =E4=B8=8B=E5=8D=88, Xie Yongji wrote: > > This patch introduces a workqueue to support injecting > > virtqueue's interrupt asynchronously. This is mainly > > for performance considerations which makes sure the push() > > and pop() for used vring can be asynchronous. > > > Do you have pref numbers for this patch? > No, I can do some tests for it if needed. Another problem is the VIRTIO_RING_F_EVENT_IDX feature will be useless if we call irq callback in ioctl context. Something like: virtqueue_push(); virtio_notify(); ioctl() ------------------------------------------------- irq_cb() virtqueue_get_buf() The used vring is always empty each time we call virtqueue_push() in userspace. Not sure if it is what we expected. Thanks, Yongji