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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 45C66C71153 for ; Mon, 4 Sep 2023 10:43:56 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qd72r-0007Lu-Tp; Mon, 04 Sep 2023 06:43:01 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qd72p-0007IW-Vu for qemu-devel@nongnu.org; Mon, 04 Sep 2023 06:43:00 -0400 Received: from mail-ej1-x62b.google.com ([2a00:1450:4864:20::62b]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1qd72l-0008Cj-Lp for qemu-devel@nongnu.org; Mon, 04 Sep 2023 06:42:59 -0400 Received: by mail-ej1-x62b.google.com with SMTP id a640c23a62f3a-99c1d03e124so178913666b.2 for ; Mon, 04 Sep 2023 03:42:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1693824173; x=1694428973; darn=nongnu.org; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=MOZJzkZakFMckOaI4fXPgUEk0n7nzjmGUaJ5sMvdQtk=; b=eZnGz/rZC2VoYLiecuSrwXge0o91OBpldj5A2zEfcUINjvAJVHz+zZqmoxIVhKyWFM yc3dHTNGxKLKZ7Xazpy679l6W07j+8NP5RWjGd9KYecYLRA7YhIqqmMsKyxKlKmwBnEJ SkZxEYc5x/DE9swUITtXwNEqLzXNatP+3d93O29vItqp1jkiPUa5KJ0UrdlmyaZOI/Md 3Ai5OE2WBemQ6dcAH4Hmb7lGO0LKSm+3BcFSF97IvoKOlamPblAnZeE8vHVW0B+ghvUE Z3elzi8N4Vbo7qF/s+O0h1TOzUQUczd07YtflivAG4ILZ8TLKt9zvHCMJR9G0KmSK+tU 18iA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1693824173; x=1694428973; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=MOZJzkZakFMckOaI4fXPgUEk0n7nzjmGUaJ5sMvdQtk=; b=ZxphlxMDNKmneEx2y71ygC3BHmWntOSg1e76Lu16FoGF2G9bC6XkbLN57eZhje4Ghd QyeBQiW9uxEc50obeMWBd3cP8NuqP1tUmIJ4gR7FDbkqwtsNeZi3EqBCavFRR7ur4+W1 XvkfIcAz2oQoewsY21Xw1bcCdMdznAkHTD+BfqIHa1Vvgnl41oflyjT7EuriAl4xx37G UY8V8x3XlshtUKLltR9UDoJCqLd2R1MNug35vCIAIV1Pa8KWkzTI988567JDSIkISbXq 2RI4CdBJMVQNxkLAOIJ6O4cXjvMquzqfq8U/6GxGPnFArRQdq6mi8cB09B0nnn2xHj8J tJyg== X-Gm-Message-State: AOJu0YxAXg4WBuyV1rfPB8IApkyG+yAd6fjADIjEXjZuu6HQv4EacHjm IaagSpmeMaSce8zA4em3HEZLag== X-Google-Smtp-Source: AGHT+IEgXOMN+FFkI4j7xv9SbVYZNeITQuBn4QcZNpM4LAdwfZNESANAcbV29rcRmL0H81UD+0roYg== X-Received: by 2002:a17:907:2cd9:b0:9a2:120a:5779 with SMTP id hg25-20020a1709072cd900b009a2120a5779mr6416125ejc.60.1693824173378; Mon, 04 Sep 2023 03:42:53 -0700 (PDT) Received: from [192.168.69.115] ([176.187.209.227]) by smtp.gmail.com with ESMTPSA id r22-20020a170906365600b009a5f1d1564dsm5927328ejb.126.2023.09.04.03.42.51 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 04 Sep 2023 03:42:52 -0700 (PDT) Message-ID: Date: Mon, 4 Sep 2023 12:42:50 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.15.0 Subject: Re: [PATCH v8 03/12] virtio-sound: handle control messages and streams Content-Language: en-US To: Manos Pitsidianakis , qemu-devel@nongnu.org Cc: Igor Skalkin , Anton Yakovlev , Paolo Bonzini , Gerd Hoffmann , "ichael S. Tsirkin" , Marcel Apfelbaum , =?UTF-8?Q?Daniel_P=2e_Berrang=c3=a9?= , Eduardo Habkost , =?UTF-8?Q?Marc-Andr_=c3=a9_Lureau?= , =?UTF-8?Q?Volker_R_=c3=bc_melin?= , =?UTF-8?B?S8WRIHbDoSBnw7MgLCBab2x0w6Egbg==?= , =?UTF-8?Q?Alex_Benn_=c3=a9_e?= References: <0gi88.o687yqrpqd24@linaro.org> From: =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= In-Reply-To: <0gi88.o687yqrpqd24@linaro.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2a00:1450:4864:20::62b; envelope-from=philmd@linaro.org; helo=mail-ej1-x62b.google.com X-Spam_score_int: -35 X-Spam_score: -3.6 X-Spam_bar: --- X-Spam_report: (-3.6 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-1.473, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 4/9/23 12:18, Manos Pitsidianakis wrote: > Good morning Philippe, > > On Mon, 04 Sep 2023 13:08, Philippe Mathieu-Daudé > wrote: >>> +    iov_from_buf(cmd->elem->in_sg, >>> +                 cmd->elem->in_num, >>> +                 0, >>> +                 &cmd->resp, >>> +                 sizeof(cmd->resp)); >>> +    virtqueue_push(cmd->vq, cmd->elem, sizeof(cmd->elem)); >>> +    virtio_notify(VIRTIO_DEVICE(s), cmd->vq); >> >> I have very few understanding of virtio, but I'm wondering here, >> since this function is called under cmdq_mutex(), could it be >> useful to batch the queue by calling virtio_notify() only once >> in the caller once the whole cmdq is processed ... > > In the linux driver (sound/virtio/virtio_ctl_msg.c), the guest has a > timeout for receiving the message. I found that if I did not notify as > fast as possible, I got timeout errors on the guest. Ah, I see, 1ms per default: sound/virtio/virtio_card.c:14:u32 virtsnd_msg_timeout_ms = MSEC_PER_SEC;