From patchwork Fri Jul 16 15:34:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Abeni X-Patchwork-Id: 479570 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=-16.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS autolearn=ham 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 F3F75C07E95 for ; Fri, 16 Jul 2021 15:34:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DFF2A60238 for ; Fri, 16 Jul 2021 15:34:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241053AbhGPPhr (ORCPT ); Fri, 16 Jul 2021 11:37:47 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:54355 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241022AbhGPPho (ORCPT ); Fri, 16 Jul 2021 11:37:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1626449689; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=azzTV7NVSdjWfH7vqRJWElEUXdLny7F98+w/WRshApo=; b=dMd1e4K2a9+NU/mb1yX1spWQjwvawiA9t8cu0qiXsNqFMahojt0fJrUWFaGdwu2GqX0B8u bnhacPgaYBt6XIpU7xsCaJSiDyOOFohi4v6EiQQvXniACsIOdxil1kr1plEJVpZ1UpIKl7 imTFKrdZ0koZccUks/wWbu9k4lT+dmw= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-284-gL09kQQcPSe2KcucTHOVyw-1; Fri, 16 Jul 2021 11:34:46 -0400 X-MC-Unique: gL09kQQcPSe2KcucTHOVyw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B0C88801B34; Fri, 16 Jul 2021 15:34:45 +0000 (UTC) Received: from gerbillo.redhat.com (ovpn-113-207.ams2.redhat.com [10.36.113.207]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5B14F5C1A1; Fri, 16 Jul 2021 15:34:44 +0000 (UTC) From: Paolo Abeni To: netdev@vger.kernel.org Cc: "David S. Miller" , Jakub Kicinski , Shuah Khan , toke@redhat.com Subject: [PATCH RFC v2 3/5] veth: implement support for set_channel ethtool op Date: Fri, 16 Jul 2021 17:34:21 +0200 Message-Id: <111ce5aebbd7fdfab5e091bbd37dcea1f5ae3f8d.1626449533.git.pabeni@redhat.com> In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This change implements the set_channel() ethtool operation, preserving the current defaults values and allowing up set the number of queues in the range set ad device creation time. The update operation tries hard to leave the device in a consistent status in case of errors. RFC v1 -> RFC v2: - don't flip device status on set_channel() - roll-back the changes if possible on error - Jackub Signed-off-by: Paolo Abeni --- drivers/net/veth.c | 125 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 123 insertions(+), 2 deletions(-) diff --git a/drivers/net/veth.c b/drivers/net/veth.c index 9eb8c1034e98..ae869c097587 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -224,10 +224,13 @@ static void veth_get_channels(struct net_device *dev, { channels->tx_count = dev->real_num_tx_queues; channels->rx_count = dev->real_num_rx_queues; - channels->max_tx = dev->real_num_tx_queues; - channels->max_rx = dev->real_num_rx_queues; + channels->max_tx = dev->num_tx_queues; + channels->max_rx = dev->num_rx_queues; } +static int veth_set_channels(struct net_device *dev, + struct ethtool_channels *ch); + static const struct ethtool_ops veth_ethtool_ops = { .get_drvinfo = veth_get_drvinfo, .get_link = ethtool_op_get_link, @@ -237,6 +240,7 @@ static const struct ethtool_ops veth_ethtool_ops = { .get_link_ksettings = veth_get_link_ksettings, .get_ts_info = ethtool_op_get_ts_info, .get_channels = veth_get_channels, + .set_channels = veth_set_channels, }; /* general routines */ @@ -1136,6 +1140,123 @@ static int veth_napi_enable(struct net_device *dev) return veth_napi_enable_range(dev, 0, dev->real_num_rx_queues); } +static void veth_disable_range_safe(struct net_device *dev, int start, int end) +{ + struct veth_priv *priv = netdev_priv(dev); + + if (start >= end) + return; + + if (priv->_xdp_prog) { + veth_napi_del_range(dev, start, end); + veth_disable_xdp_range(dev, start, end, false); + } else if (veth_gro_requested(dev)) { + veth_napi_del_range(dev, start, end); + } +} + +static int veth_enable_range_safe(struct net_device *dev, int start, int end) +{ + struct veth_priv *priv = netdev_priv(dev); + int err; + + if (start >= end) + return 0; + + if (priv->_xdp_prog) { + /* these channels are freshly initialized, napi is not on there even + * when GRO is requeste + */ + err = veth_enable_xdp_range(dev, start, end, false); + if (err) + return err; + + err = __veth_napi_enable_range(dev, start, end); + if (err) { + /* on error always delete the newly added napis */ + veth_disable_xdp_range(dev, start, end, true); + return err; + } + } else if (veth_gro_requested(dev)) { + return veth_napi_enable_range(dev, start, end); + } + return 0; +} + +static int veth_set_channels(struct net_device *dev, + struct ethtool_channels *ch) +{ + struct veth_priv *priv = netdev_priv(dev); + unsigned int old_rx_count, new_rx_count; + struct veth_priv *peer_priv; + struct net_device *peer; + int err; + + /* sanity check. Upper bounds are already enforced by the caller */ + if (!ch->rx_count || !ch->tx_count) + return -EINVAL; + + /* avoid braking XDP, if that is enabled */ + peer = rtnl_dereference(priv->peer); + peer_priv = peer ? netdev_priv(peer) : NULL; + if (priv->_xdp_prog && peer && ch->rx_count < peer->real_num_tx_queues) + return -EINVAL; + + if (peer && peer_priv && peer_priv->_xdp_prog && ch->tx_count > peer->real_num_rx_queues) + return -EINVAL; + + old_rx_count = dev->real_num_rx_queues; + new_rx_count = ch->rx_count; + if (netif_running(dev)) { + /* turn device off */ + netif_carrier_off(dev); + if (peer) + netif_carrier_off(peer); + + /* try to allocate new resurces, as needed*/ + err = veth_enable_range_safe(dev, old_rx_count, new_rx_count); + if (err) + goto out; + } + + err = netif_set_real_num_rx_queues(dev, ch->rx_count); + if (err) + goto revert; + + err = netif_set_real_num_tx_queues(dev, ch->tx_count); + if (err) { + int err2 = netif_set_real_num_rx_queues(dev, old_rx_count); + + /* this error condition could happen only if rx and tx change + * in opposite directions (e.g. tx nr raises, rx nr decreases) + * and we can't do anything to fully restore the original + * status + */ + if (err2) + pr_warn("Can't restore rx queues config %d -> %d %d", + new_rx_count, old_rx_count, err2); + else + goto revert; + } + +out: + if (netif_running(dev)) { + /* note that we need to swap the arguments WRT the enable part + * to identify the range we have to disable + */ + veth_disable_range_safe(dev, new_rx_count, old_rx_count); + netif_carrier_on(dev); + if (peer) + netif_carrier_on(peer); + } + return err; + +revert: + new_rx_count = old_rx_count; + old_rx_count = ch->rx_count; + goto out; +} + static int veth_open(struct net_device *dev) { struct veth_priv *priv = netdev_priv(dev);