From nobody Sun Nov 24 13:41:37 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1722956253; cv=none; d=zohomail.com; s=zohoarc; b=VX/axHFzJf5mUWT3VMUiNwE1RBaG0rBpdqldN8dalnCNLCGgKBEatJzpUTtllmvIl5Ft2ctnoMNJ3JdlsL39SQHVyrKcwZ2JiMLoa9ytSYmaRdRX/Acle08eavstr7oh2Uzne58sE24uU+JD0dG394cKbfOQabWBTNshkarxmR8= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1722956253; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=9ZaMrzQ/FCMzS6IV9NFuh3edTIO49KNcTeKHAheYESk=; b=DFJAm3+/AIJuI+u89Y1usFdOFJZ0De4l+OpfBa0k6TDGyjNyKbAdqwlruKmjQ5Io9UIG6u0U3npsbsEukkZX96+lyZIVPAANTDjRgXYxyPsF92HL3EK7pYUaOc7dqUNQo6+ND2SYPMpXletsrmExZ9G9IvKNv5Sm/yG1p3i+sIc= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1722956253128549.203673050645; Tue, 6 Aug 2024 07:57:33 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sbLck-0001n4-VL; Tue, 06 Aug 2024 10:57:19 -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 1sbLcj-0001hd-Cu for qemu-devel@nongnu.org; Tue, 06 Aug 2024 10:57:17 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sbLcg-0001xb-K0 for qemu-devel@nongnu.org; Tue, 06 Aug 2024 10:57:17 -0400 Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-591-meqAoqOuPT2-yJzBkrpjbw-1; Tue, 06 Aug 2024 10:57:10 -0400 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 3891F19560B3; Tue, 6 Aug 2024 14:57:09 +0000 (UTC) Received: from toolbox.redhat.com (unknown [10.42.28.106]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 218A419560AE; Tue, 6 Aug 2024 14:57:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1722956233; 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=9ZaMrzQ/FCMzS6IV9NFuh3edTIO49KNcTeKHAheYESk=; b=c6AGoZV2iJRRDt8fo+3tlsy9PvxFlgDq0DgNWzlkV85+Dx1adIiQLlDeqoaEvjqs5dJobV qoLowwTcor/CMJjBvN6QD38mphkyTEUhCl8BW5MCMZ/8PSVEHES7zj4UcrHfZv43Sd030H CM1XWfgV8BqxKuxfYWC109fGd7jKR58= X-MC-Unique: meqAoqOuPT2-yJzBkrpjbw-1 From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: Jason Wang , Yuri Benditovich , "Michael S. Tsirkin" , Andrew Melnychenko , =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= Subject: [PATCH 4/5] hw/net: report errors from failing to use eBPF RSS FDs Date: Tue, 6 Aug 2024 15:56:52 +0100 Message-ID: <20240806145653.1632478-5-berrange@redhat.com> In-Reply-To: <20240806145653.1632478-1-berrange@redhat.com> References: <20240806145653.1632478-1-berrange@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.144, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, 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+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1722956255230116600 If the user/mgmt app passed in a set of pre-opened FDs for eBPF RSS, then it is expecting QEMU to use them. Any failure to do so must be considered a fatal error and propagated back up the stack, otherwise deployment mistakes will not be detectable in a prompt manner. When not using pre-opened FDs, then eBPF RSS is tried on a "best effort" basis only and thus fallback to software RSS is valid. Signed-off-by: Daniel P. Berrang=C3=A9 --- hw/net/virtio-net.c | 40 ++++++++++++++++++++++++++++------------ 1 file changed, 28 insertions(+), 12 deletions(-) diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 85323322ea..cfcf3e1f1a 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -1315,28 +1315,27 @@ static void virtio_net_disable_rss(VirtIONet *n) virtio_net_commit_rss_config(n); } =20 -static bool virtio_net_load_ebpf_fds(VirtIONet *n) +static bool virtio_net_load_ebpf_fds(VirtIONet *n, Error **errp) { int fds[EBPF_RSS_MAX_FDS] =3D { [0 ... EBPF_RSS_MAX_FDS - 1] =3D -1}; int ret =3D true; int i =3D 0; =20 if (n->nr_ebpf_rss_fds !=3D EBPF_RSS_MAX_FDS) { - warn_report("Expected %d file descriptors but got %d", - EBPF_RSS_MAX_FDS, n->nr_ebpf_rss_fds); - return false; - } + error_setg(errp, "Expected %d file descriptors but got %d", + EBPF_RSS_MAX_FDS, n->nr_ebpf_rss_fds); + return false; + } =20 for (i =3D 0; i < n->nr_ebpf_rss_fds; i++) { - fds[i] =3D monitor_fd_param(monitor_cur(), n->ebpf_rss_fds[i], - &error_warn); + fds[i] =3D monitor_fd_param(monitor_cur(), n->ebpf_rss_fds[i], err= p); if (fds[i] < 0) { ret =3D false; goto exit; } } =20 - ret =3D ebpf_rss_load_fds(&n->ebpf_rss, fds[0], fds[1], fds[2], fds[3]= , NULL); + ret =3D ebpf_rss_load_fds(&n->ebpf_rss, fds[0], fds[1], fds[2], fds[3]= , errp); =20 exit: if (!ret) { @@ -1348,13 +1347,15 @@ exit: return ret; } =20 -static bool virtio_net_load_ebpf(VirtIONet *n) +static bool virtio_net_load_ebpf(VirtIONet *n, Error **errp) { bool ret =3D false; =20 if (virtio_net_attach_ebpf_to_backend(n->nic, -1)) { - if (!(n->ebpf_rss_fds && virtio_net_load_ebpf_fds(n))) { - ret =3D ebpf_rss_load(&n->ebpf_rss, NULL); + if (n->ebpf_rss_fds) { + ret =3D virtio_net_load_ebpf_fds(n, errp); + } else { + ret =3D ebpf_rss_load(&n->ebpf_rss, errp); } } =20 @@ -3760,7 +3761,22 @@ static void virtio_net_device_realize(DeviceState *d= ev, Error **errp) net_rx_pkt_init(&n->rx_pkt); =20 if (virtio_has_feature(n->host_features, VIRTIO_NET_F_RSS)) { - virtio_net_load_ebpf(n); + Error *err =3D NULL; + if (!virtio_net_load_ebpf(n, &err)) { + /* + * If user explicitly gave QEMU RSS FDs to use, then + * failing to use them must be considered a fatal + * error. If no RSS FDs were provided, QEMU is trying + * eBPF on a "best effort" basis only, so report a + * warning and allow fallback to software RSS. + */ + if (n->ebpf_rss_fds) { + error_propagate(errp, err); + } else { + warn_report("unable to load eBPF RSS: %s", error_get_prett= y(err)); + error_free(err); + } + } } } =20 --=20 2.45.2