Received: by 2002:a05:6358:11c7:b0:104:8066:f915 with SMTP id i7csp2497145rwl; Thu, 13 Apr 2023 07:15:00 -0700 (PDT) X-Google-Smtp-Source: AKy350ZRCU45S95RffyOlsLSnEKRcw1XeVoR3yiYEUkl80bp3OvNXBXC8ZsJxaFCiWwZ6Ed7neoi X-Received: by 2002:a6b:fe02:0:b0:760:a3c7:1a86 with SMTP id x2-20020a6bfe02000000b00760a3c71a86mr1058239ioh.16.1681395299966; Thu, 13 Apr 2023 07:14:59 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1681395299; cv=none; d=google.com; s=arc-20160816; b=y5DSHqMGlid+OE/3zBGLr6m8UyY9MOVcabiZDOPY4i0aVQvUhA4xL902I9RTfXPXi0 Wk1JTU/6FnxWafXdtqZX8RDVxSTR92nqr2je4WvqZ1e0Cbs9ZlIWQ1toAVoTTgpFS+Wn wWLYrUmO0/D6QkNjGTY1gszr1U/v7k2dPK7uneMssD16CaZ1FSnHQU9tPgE4I+Gw+rjK G7XYWlz+mhTvFMCJ9kamwhs+su4qS9+XWow5ECJuzbAHlxvcN0tiNZQPCL+a6dvMpuTX a+DfrCDnntrXrxtXhOPKU6TkZlax4yC7iyKHxvIZ0Vyl3dDociZHHxezkKhnddFgw1h0 d+iw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:subject:cc:to:from:date :dkim-signature; bh=qdPwXC9Odph3WU3ZluvYTnLuSaO695Y52kR6dJl7SiU=; b=XPjcL5qJZztZkIbVwBiOm1v5RE+UzghnFEo8pltj81juoCAxObLnrnydv9CGCtwysv 7x6xDEJAMUzqc44jIE2c3j9vVlaROQz2IlQ9L17yQJ2b/t+9Z/1L6/CnBIfjNsavmefP bJsFEEQepl8mkk5d+6SborKUc5JWBP3I1GWbAysV6XPFbqYVUtghocHBoooX7YXbGPWZ mqaFmq7eTIfOt/nTYEfj+WocTWUl6wmN/Sz6MHkwah+TZUE68BpOr4KE8Y3bsIGMIdxD y1ez6cuwm4DB7eTDyvb5O6ec5Uq551J07sXl3C9nTen+Epf+nEKVOjhn8qtx+emtbu/Y b3yw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=H+CUkiL5; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Return-Path: Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id d4-20020a5d9bc4000000b0076090988cdasi1795483ion.18.2023.04.13.07.14.46; Thu, 13 Apr 2023 07:14:59 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=H+CUkiL5; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231739AbjDMOEU (ORCPT + 99 others); Thu, 13 Apr 2023 10:04:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37716 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229899AbjDMOEN (ORCPT ); Thu, 13 Apr 2023 10:04:13 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D0F73A243 for ; Thu, 13 Apr 2023 07:04:10 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6968663EEB for ; Thu, 13 Apr 2023 14:04:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5B0B2C433D2; Thu, 13 Apr 2023 14:04:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1681394649; bh=Ahx2IXPmgRvW3Kytgy7tTXDRUFlVeZwHebwdBqNN2CM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=H+CUkiL5VYYP3GYAQiplu72EifG+opq0EChsi7A90f9IDZur/fgTtuuKNDFVSWfnW PVPr1FbWbLNDPnr7NFsujmbf/2jDac9N7E6cv1MyiH0sz7GFBwOMxVSqcqDGBk39/y +txKnvP2rkegLrqYTT/wOgwuJw5YX6AXcGPu339MqLm0AjVWvG/wJqJGeEC455EmRO z38M/Wi1m/+ApQVwBLMS9rTG8BH80EV193nEL18ULLznXFUJ6GQg5LeaggFUpIKfuO SiVoQiHIIsyREnJRV9qbfX/CEEgjNwIGx0EdJKW72z8dUD/kTYCUOxGR2xe/Se6VE7 UpLvVxCLRiEPQ== Date: Thu, 13 Apr 2023 07:04:08 -0700 From: Jakub Kicinski To: Jason Wang Cc: mst@redhat.com, davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, maxime.coquelin@redhat.com, alvaro.karsz@solid-run.com, eperezma@redhat.com, xuanzhuo@linux.alibaba.com, david.marchand@redhat.com Subject: Re: [PATCH net-next V2 0/2] virtio-net: don't busy poll for cvq command Message-ID: <20230413070408.630fa731@kernel.org> In-Reply-To: <20230413064027.13267-1-jasowang@redhat.com> References: <20230413064027.13267-1-jasowang@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-7.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_HI, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 13 Apr 2023 14:40:25 +0800 Jason Wang wrote: > The code used to busy poll for cvq command which turns out to have > several side effects: > > 1) infinite poll for buggy devices > 2) bad interaction with scheduler > > So this series tries to use sleep instead of busy polling. In this > version, I take a step back: the hardening part is not implemented and > leave for future investigation. We use to aggree to use interruptible > sleep but it doesn't work for a general workqueue. CC: netdev missing?