From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id C7799A00BE; Tue, 19 Apr 2022 11:10:38 +0200 (CEST) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 6752D4068E; Tue, 19 Apr 2022 11:10:38 +0200 (CEST) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by mails.dpdk.org (Postfix) with ESMTP id D17BE40687 for ; Tue, 19 Apr 2022 11:10:36 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1650359436; 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=Cqmuw9GgREuaZGMAIUqaPxwEuzICb/kHbBZfGjsgzVI=; b=F4jBvNn1ZASkSS0gTQV/7oE0YG4VuOqqk6I/Ug5IpQ6V1k5VnmZYw7Qjs6VSxW3MBbgU3p IiuHPa57ZwTAlX2tHBrzGSXv9QtcIbxTe5kJVTl48lQ408URmNZeepKRubER4zaE/46rS/ FD9GmR2NLNAf8oQkCXK6UEqMXWKouQk= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-610-e8Fme8UJNVWJd564oUgrFw-1; Tue, 19 Apr 2022 05:10:30 -0400 X-MC-Unique: e8Fme8UJNVWJd564oUgrFw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 34AB1185A794; Tue, 19 Apr 2022 09:10:30 +0000 (UTC) Received: from [10.39.208.35] (unknown [10.39.208.35]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 063A2215CDD2; Tue, 19 Apr 2022 09:10:28 +0000 (UTC) Message-ID: Date: Tue, 19 Apr 2022 11:10:27 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH] vhost: support sync copy when data buffer is small To: Wenwu Ma , chenbo.xia@intel.com, dev@dpdk.org Cc: jiayu.hu@intel.com, yinan.wang@intel.com, xingguang.he@intel.com, weix.ling@intel.com References: <20220411133836.200783-1-wenwux.ma@intel.com> From: Maxime Coquelin In-Reply-To: <20220411133836.200783-1-wenwux.ma@intel.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=maxime.coquelin@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Hi Wenwu, On 4/11/22 15:38, Wenwu Ma wrote: > In async datapath, if the length of data buffer > is less than 256, the data will be copied by CPU > instead of DMA. > > Signed-off-by: Wenwu Ma > --- > lib/vhost/vhost.h | 6 ++- > lib/vhost/virtio_net.c | 96 ++++++++++++++++++++++++++++++------------ > 2 files changed, 73 insertions(+), 29 deletions(-) > As I mentioned in the past, let's have a DMA-only solution working before trying to support CPU copy for small packets. Thanks, Maxime