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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=unavailable 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 A3C76C04AA7 for ; Mon, 13 May 2019 10:05:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7F6D2208C2 for ; Mon, 13 May 2019 10:05:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728845AbfEMKFN (ORCPT ); Mon, 13 May 2019 06:05:13 -0400 Received: from mx1.redhat.com ([209.132.183.28]:21986 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727690AbfEMKFN (ORCPT ); Mon, 13 May 2019 06:05:13 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id 1493D3082E1E; Mon, 13 May 2019 10:05:13 +0000 (UTC) Received: from [10.72.12.49] (ovpn-12-49.pek2.redhat.com [10.72.12.49]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7EE306A96C; Mon, 13 May 2019 10:05:03 +0000 (UTC) Subject: Re: [PATCH v2 8/8] vsock/virtio: make the RX buffer size tunable To: Stefano Garzarella , netdev@vger.kernel.org Cc: "David S. Miller" , "Michael S. Tsirkin" , virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Stefan Hajnoczi References: <20190510125843.95587-1-sgarzare@redhat.com> <20190510125843.95587-9-sgarzare@redhat.com> From: Jason Wang Message-ID: Date: Mon, 13 May 2019 18:05:02 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190510125843.95587-9-sgarzare@redhat.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 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Mon, 13 May 2019 10:05:13 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 2019/5/10 下午8:58, Stefano Garzarella wrote: > The RX buffer size determines the memory consumption of the > vsock/virtio guest driver, so we make it tunable through > a module parameter. > > The size allowed are between 4 KB and 64 KB in order to be > compatible with old host drivers. > > Suggested-by: Stefan Hajnoczi > Signed-off-by: Stefano Garzarella I don't see much value of doing this through kernel command line. We should deal with them automatically like what virtio-net did. Or even a module parameter is better. Thanks > --- > include/linux/virtio_vsock.h | 1 + > net/vmw_vsock/virtio_transport.c | 27 ++++++++++++++++++++++++++- > 2 files changed, 27 insertions(+), 1 deletion(-) > > diff --git a/include/linux/virtio_vsock.h b/include/linux/virtio_vsock.h > index 5a9d25be72df..b9f8c3d91f80 100644 > --- a/include/linux/virtio_vsock.h > +++ b/include/linux/virtio_vsock.h > @@ -13,6 +13,7 @@ > #define VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE (1024 * 64) > #define VIRTIO_VSOCK_MAX_BUF_SIZE 0xFFFFFFFFUL > #define VIRTIO_VSOCK_MAX_PKT_BUF_SIZE (1024 * 64) > +#define VIRTIO_VSOCK_MIN_PKT_BUF_SIZE (1024 * 4) > > enum { > VSOCK_VQ_RX = 0, /* for host to guest data */ > diff --git a/net/vmw_vsock/virtio_transport.c b/net/vmw_vsock/virtio_transport.c > index af1d2ce12f54..732398b4e28f 100644 > --- a/net/vmw_vsock/virtio_transport.c > +++ b/net/vmw_vsock/virtio_transport.c > @@ -66,6 +66,31 @@ struct virtio_vsock { > u32 guest_cid; > }; > > +static unsigned int rx_buf_size = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE; > + > +static int param_set_rx_buf_size(const char *val, const struct kernel_param *kp) > +{ > + unsigned int size; > + int ret; > + > + ret = kstrtouint(val, 0, &size); > + if (ret) > + return ret; > + > + if (size < VIRTIO_VSOCK_MIN_PKT_BUF_SIZE || > + size > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) > + return -EINVAL; > + > + return param_set_uint(val, kp); > +}; > + > +static const struct kernel_param_ops param_ops_rx_buf_size = { > + .set = param_set_rx_buf_size, > + .get = param_get_uint, > +}; > + > +module_param_cb(rx_buf_size, ¶m_ops_rx_buf_size, &rx_buf_size, 0644); > + > static struct virtio_vsock *virtio_vsock_get(void) > { > return the_virtio_vsock; > @@ -261,7 +286,7 @@ virtio_transport_cancel_pkt(struct vsock_sock *vsk) > > static void virtio_vsock_rx_fill(struct virtio_vsock *vsock) > { > - int buf_len = VIRTIO_VSOCK_DEFAULT_RX_BUF_SIZE; > + int buf_len = rx_buf_size; > struct virtio_vsock_pkt *pkt; > struct scatterlist hdr, buf, *sgs[2]; > struct virtqueue *vq;