From patchwork Mon Dec 28 16:22:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Willem de Bruijn X-Patchwork-Id: 352918 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 84056C43381 for ; Mon, 28 Dec 2020 16:23:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 561DE2084D for ; Mon, 28 Dec 2020 16:23:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2633300AbgL1QXW (ORCPT ); Mon, 28 Dec 2020 11:23:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52040 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2440986AbgL1QXU (ORCPT ); Mon, 28 Dec 2020 11:23:20 -0500 Received: from mail-qv1-xf36.google.com (mail-qv1-xf36.google.com [IPv6:2607:f8b0:4864:20::f36]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E9D7AC061796 for ; Mon, 28 Dec 2020 08:22:39 -0800 (PST) Received: by mail-qv1-xf36.google.com with SMTP id p5so5146192qvs.7 for ; Mon, 28 Dec 2020 08:22:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=vQsWqZSCnMr1x/EzF/kzhHSUUJGM29HYm08xu/2fjmE=; b=a7r3Z2CBMpz7h38KBUNrKg/8UT6W3Yw49Otjw8kRDRqEKPPT2nizEk67WHBHJwVcE6 57nPbkaGZbWsPM0WCmfWG4zFe11Dh5BdAhO5sKi7rASiHegTjP47BBQ1Y83GlhqQbs/3 lvRqNBJf1UK9H5ycT8FxGQAoX4uqT6qzXXvPL6UTcD4sgXm1XjT8FlcsHidRqBbx7F86 PPCDWa8bnXz1GUqNrRN+m1nh43xoqE8MdOqkloYFkR7Tpy3KBI55xSk6HUEDFbcymYvi UvMDDR3eem5RXpPiw8Lf6JQxDEmgJ/mco0chJSsU6ZoHXCRNjqcIart4OKSJyveMho3k w49Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=vQsWqZSCnMr1x/EzF/kzhHSUUJGM29HYm08xu/2fjmE=; b=fsoUqR/BhN/p4+kBtExKfahiNFfi7JUc9UtCHJAGaMweMMtE4w10kCrmQRQigiKUOD 5cqb1DmTlBAVuy7XW4oz7ZaZSiAkcCzgS3DVaBO1WILy2MWwNBvSryR9Xcv3xVll8w/m 01ymXYNBvbCJhny0Cz3FnKcnfIVg0BfhzRzS4E7lUJW+BnKiW3bSZWgOe/qvpPZP6oYb ShDnljsGYyH2kWQvpZyQbHB1LlPqiKAS7z9R88pOTiELxFub9a8IqFsxmjn0txje0Fkj t4ghuTj6gVUvNRELlPm75vy3FJkgxLKbQ9CdlAcQoMufFQ79+3IQsiJ61Lm+eyUCPY6N 33mQ== X-Gm-Message-State: AOAM531W1LQ6GBWuxnUqI58GoXKc3pAYVX3QBZ2BJEi7Q3AvuX6uwUM0 Q7GVylZ2rHwuylk4psAo/5Y= X-Google-Smtp-Source: ABdhPJx3TAGUQMPRKMmT3Y9uUkxQtN1ZuRA6AKf8I+fo2yanHcrz4Nm9p6V5c4DvbopY8iekLMzsgw== X-Received: by 2002:ad4:4108:: with SMTP id i8mr47649560qvp.49.1609172559222; Mon, 28 Dec 2020 08:22:39 -0800 (PST) Received: from willemb.nyc.corp.google.com ([2620:0:1003:312:f693:9fff:fef4:3e8a]) by smtp.gmail.com with ESMTPSA id u65sm24005556qkb.58.2020.12.28.08.22.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 28 Dec 2020 08:22:38 -0800 (PST) From: Willem de Bruijn To: virtualization@lists.linux-foundation.org Cc: netdev@vger.kernel.org, mst@redhat.com, jasowang@redhat.com, Willem de Bruijn Subject: [PATCH rfc 2/3] virtio-net: support receive timestamp Date: Mon, 28 Dec 2020 11:22:32 -0500 Message-Id: <20201228162233.2032571-3-willemdebruijn.kernel@gmail.com> X-Mailer: git-send-email 2.29.2.729.g45daf8777d-goog In-Reply-To: <20201228162233.2032571-1-willemdebruijn.kernel@gmail.com> References: <20201228162233.2032571-1-willemdebruijn.kernel@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Willem de Bruijn Add optional PTP hardware timestamp offload for virtio-net. Accurate RTT measurement requires timestamps close to the wire. Introduce virtio feature VIRTIO_NET_F_RX_TSTAMP. If negotiated, the virtio-net header is expanded with room for a timestamp. A host may pass receive timestamps for all or some packets. A timestamp is valid if non-zero. The timestamp straddles (virtual) hardware domains. Like PTP, use international atomic time (CLOCK_TAI) as global clock base. It is guest responsibility to sync with host, e.g., through kvm-clock. Signed-off-by: Willem de Bruijn Reported-by: kernel test robot --- drivers/net/virtio_net.c | 20 +++++++++++++++++++- include/uapi/linux/virtio_net.h | 12 ++++++++++++ 2 files changed, 31 insertions(+), 1 deletion(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index b917b7333928..57744bb6a141 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -204,6 +204,9 @@ struct virtnet_info { /* Guest will pass tx path info to the host */ bool has_tx_hash; + /* Host will pass CLOCK_TAI receive time to the guest */ + bool has_rx_tstamp; + /* Has control virtqueue */ bool has_cvq; @@ -292,6 +295,13 @@ static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb) return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb; } +static inline struct virtio_net_hdr_v12 *skb_vnet_hdr_12(struct sk_buff *skb) +{ + BUILD_BUG_ON(sizeof(struct virtio_net_hdr_v12) > sizeof(skb->cb)); + + return (void *)skb->cb; +} + /* * private is used to chain pages for big packets, put the whole * most recent used list in the beginning for reuse @@ -1082,6 +1092,9 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq, goto frame_err; } + if (vi->has_rx_tstamp) + skb_hwtstamps(skb)->hwtstamp = ns_to_ktime(skb_vnet_hdr_12(skb)->tstamp); + skb_record_rx_queue(skb, vq2rxq(rq->vq)); skb->protocol = eth_type_trans(skb, dev); pr_debug("Receiving skb proto 0x%04x len %i type %i\n", @@ -3071,6 +3084,11 @@ static int virtnet_probe(struct virtio_device *vdev) vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash); } + if (virtio_has_feature(vdev, VIRTIO_NET_F_RX_TSTAMP)) { + vi->has_rx_tstamp = true; + vi->hdr_len = sizeof(struct virtio_net_hdr_v12); + } + if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) || virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) vi->any_header_sg = true; @@ -3261,7 +3279,7 @@ static struct virtio_device_id id_table[] = { VIRTIO_NET_F_CTRL_MAC_ADDR, \ VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \ VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \ - VIRTIO_NET_F_TX_HASH + VIRTIO_NET_F_TX_HASH, VIRTIO_NET_F_RX_TSTAMP static unsigned int features[] = { VIRTNET_FEATURES, diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h index f6881b5b77ee..0ffe2eeebd4a 100644 --- a/include/uapi/linux/virtio_net.h +++ b/include/uapi/linux/virtio_net.h @@ -57,6 +57,7 @@ * Steering */ #define VIRTIO_NET_F_CTRL_MAC_ADDR 23 /* Set MAC address */ +#define VIRTIO_NET_F_RX_TSTAMP 55 /* Host sends TAI receive time */ #define VIRTIO_NET_F_TX_HASH 56 /* Guest sends hash report */ #define VIRTIO_NET_F_HASH_REPORT 57 /* Supports hash report */ #define VIRTIO_NET_F_RSS 60 /* Supports RSS RX steering */ @@ -182,6 +183,17 @@ struct virtio_net_hdr_v1_hash { }; }; +struct virtio_net_hdr_v12 { + struct virtio_net_hdr_v1 hdr; + struct { + __le32 value; + __le16 report; + __le16 flow_state; + } hash; + __virtio32 reserved; + __virtio64 tstamp; +}; + #ifndef VIRTIO_NET_NO_LEGACY /* This header comes first in the scatter-gather list. * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated, it must