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=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 33B31C56201 for ; Tue, 24 Nov 2020 08:54:56 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4101C2073C for ; Tue, 24 Nov 2020 08:54:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hIZGBLVx" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4101C2073C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57926 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1khU69-0001Oc-Rj for qemu-devel@archiver.kernel.org; Tue, 24 Nov 2020 03:54:53 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:36242) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1khU0r-00067J-P2 for qemu-devel@nongnu.org; Tue, 24 Nov 2020 03:49:26 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:45348) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1khU0n-0001jM-8d for qemu-devel@nongnu.org; Tue, 24 Nov 2020 03:49:24 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1606207760; 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=k8dvKQTNbq11lJpGDaEEkYYW7GAaxY44XEJRV4qSNu8=; b=hIZGBLVxTLHAbyAnsZ+K+Ekv39kSfO72tKHA2wEnHgI8gytulzfkpAEri6KHn4dfDyFWZl XoD7HGyaPUh29pkBHnxTSsDRxrnSetlfUbBJjjBlKMt2V+EJqwZVCKQKbNVYSVJsQk/SRe sEm0G+jZ3RSdbMP7p28f+7q0bsc5ehI= 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-189-0w8M599vNiiT64UfPIP5sg-1; Tue, 24 Nov 2020 03:49:15 -0500 X-MC-Unique: 0w8M599vNiiT64UfPIP5sg-1 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 mimecast-mx01.redhat.com (Postfix) with ESMTPS id 5C754805BE0; Tue, 24 Nov 2020 08:49:14 +0000 (UTC) Received: from [10.72.13.120] (ovpn-13-120.pek2.redhat.com [10.72.13.120]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9E8F860873; Tue, 24 Nov 2020 08:49:08 +0000 (UTC) Subject: Re: [RFC PATCH v2 4/5] virtio-net: Added eBPF RSS to virtio-net. To: Andrew Melnychenko , mst@redhat.com References: <20201119111305.485202-1-andrew@daynix.com> <20201119111305.485202-5-andrew@daynix.com> From: Jason Wang Message-ID: Date: Tue, 24 Nov 2020 16:48:20 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20201119111305.485202-5-andrew@daynix.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jasowang@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Received-SPF: pass client-ip=216.205.24.124; envelope-from=jasowang@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: yan@daynix.com, yuri.benditovich@daynix.com, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 2020/11/19 下午7:13, Andrew Melnychenko wrote: > From: Andrew > > When RSS is enabled the device tries to load the eBPF program > to select RX virtqueue in the TUN. If eBPF can be loaded > the RSS will function also with vhost (works with kernel 5.8 and later). > Software RSS is used as a fallback with vhost=off when eBPF can't be loaded > or when hash population requested by the guest. > > Signed-off-by: Yuri Benditovich > Signed-off-by: Andrew Melnychenko > --- > hw/net/vhost_net.c | 2 + > hw/net/virtio-net.c | 120 +++++++++++++++++++++++++++++++-- > include/hw/virtio/virtio-net.h | 4 ++ > net/vhost-vdpa.c | 2 + > 4 files changed, 124 insertions(+), 4 deletions(-) > > diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c > index 24d555e764..16124f99c3 100644 > --- a/hw/net/vhost_net.c > +++ b/hw/net/vhost_net.c > @@ -71,6 +71,8 @@ static const int user_feature_bits[] = { > VIRTIO_NET_F_MTU, > VIRTIO_F_IOMMU_PLATFORM, > VIRTIO_F_RING_PACKED, > + VIRTIO_NET_F_RSS, > + VIRTIO_NET_F_HASH_REPORT, > > /* This bit implies RARP isn't sent by QEMU out of band */ > VIRTIO_NET_F_GUEST_ANNOUNCE, > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index 277289d56e..afcc3032ec 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -698,6 +698,19 @@ static void virtio_net_set_queues(VirtIONet *n) > > static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue); > > +static uint64_t fix_ebpf_vhost_features(uint64_t features) > +{ > + /* If vhost=on & CONFIG_EBPF doesn't set - disable RSS feature */ > + uint64_t ret = features; > +#ifndef CONFIG_EBPF > + virtio_clear_feature(&ret, VIRTIO_NET_F_RSS); > +#endif > + /* for now, there is no solution for populating the hash from eBPF */ > + virtio_clear_feature(&ret, VIRTIO_NET_F_HASH_REPORT); I think there's still some misunderstanding here. When "rss" is enabled via command line, qemu can't not turn it off silently, otherwise it may break migration. Instead, qemu should disable vhost-net if eBPF can't be loaded. When "hash_report" is enabled via command line, qemu should disable vhost-net unconditionally. > + > + return ret; > +} > + > static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features, > Error **errp) > { > @@ -732,9 +745,9 @@ static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features, > return features; > } > > - virtio_clear_feature(&features, VIRTIO_NET_F_RSS); > - virtio_clear_feature(&features, VIRTIO_NET_F_HASH_REPORT); > - features = vhost_net_get_features(get_vhost_net(nc->peer), features); > + features = fix_ebpf_vhost_features( > + vhost_net_get_features(get_vhost_net(nc->peer), features)); > + > vdev->backend_features = features; > > if (n->mtu_bypass_backend && > @@ -1169,12 +1182,75 @@ static int virtio_net_handle_announce(VirtIONet *n, uint8_t cmd, > } > } > > +static void virtio_net_unload_epbf_rss(VirtIONet *n); > + > static void virtio_net_disable_rss(VirtIONet *n) > { > if (n->rss_data.enabled) { > trace_virtio_net_rss_disable(); > } > n->rss_data.enabled = false; > + > + if (!n->rss_data.enabled_software_rss && ebpf_rss_is_loaded(&n->ebpf_rss)) { > + virtio_net_unload_epbf_rss(n); > + } > +} > + > +static bool virtio_net_attach_steering_ebpf(NICState *nic, int prog_fd) > +{ > + NetClientState *nc = qemu_get_peer(qemu_get_queue(nic), 0); > + if (nc == NULL || nc->info->set_steering_ebpf == NULL) { > + return false; > + } > + > + return nc->info->set_steering_ebpf(nc, prog_fd); > +} > + > +static void rss_data_to_rss_config(struct VirtioNetRssData *data, > + struct EBPFRSSConfig *config) > +{ > + config->redirect = data->redirect; > + config->populate_hash = data->populate_hash; > + config->hash_types = data->hash_types; > + config->indirections_len = data->indirections_len; > + config->default_queue = data->default_queue; > +} > + > +static bool virtio_net_load_epbf_rss(VirtIONet *n) > +{ > + struct EBPFRSSConfig config = {}; > + > + if (!n->rss_data.enabled) { > + if (ebpf_rss_is_loaded(&n->ebpf_rss)) { > + ebpf_rss_unload(&n->ebpf_rss); > + } > + return true; > + } > + > + if (!ebpf_rss_is_loaded(&n->ebpf_rss) && !ebpf_rss_load(&n->ebpf_rss)) { > + return false; > + } > + > + rss_data_to_rss_config(&n->rss_data, &config); > + > + if (!ebpf_rss_set_all(&n->ebpf_rss, &config, > + n->rss_data.indirections_table, n->rss_data.key)) { > + ebpf_rss_unload(&n->ebpf_rss); > + return false; > + } > + > + if (!virtio_net_attach_steering_ebpf(n->nic, n->ebpf_rss.program_fd)) { > + ebpf_rss_unload(&n->ebpf_rss); > + return false; > + } > + > + return true; > +} > + > +static void virtio_net_unload_epbf_rss(VirtIONet *n) > +{ > + virtio_net_attach_steering_ebpf(n->nic, -1); > + ebpf_rss_unload(&n->ebpf_rss); > } > > static uint16_t virtio_net_handle_rss(VirtIONet *n, > @@ -1208,6 +1284,7 @@ static uint16_t virtio_net_handle_rss(VirtIONet *n, > err_value = (uint32_t)s; > goto error; > } > + n->rss_data.enabled_software_rss = false; > n->rss_data.hash_types = virtio_ldl_p(vdev, &cfg.hash_types); > n->rss_data.indirections_len = > virtio_lduw_p(vdev, &cfg.indirection_table_mask); > @@ -1289,9 +1366,30 @@ static uint16_t virtio_net_handle_rss(VirtIONet *n, > goto error; > } > n->rss_data.enabled = true; > + > + if (!n->rss_data.populate_hash) { > + /* load EBPF RSS */ The code explains itself, so the comment is no necessary. > + if (!virtio_net_load_epbf_rss(n)) { Any reason that we load eBPF RSS here? I thought it would be easier to do it during set_features (e.g when RSS is negotiated but not HASH_REPORT) and if we do that we don't need extra care about migration. > + /* EBPF mast be loaded for vhost */ Typo. > + if (get_vhost_net(qemu_get_queue(n->nic)->peer)) { > + warn_report("Can't load eBPF RSS for vhost"); > + goto error; > + } > + /* fallback to software RSS */ > + warn_report("Can't load eBPF RSS - fallback to software RSS"); > + n->rss_data.enabled_software_rss = true; > + } > + } else { > + /* use software RSS for hash populating */ > + /* and unload eBPF if was loaded before */ > + virtio_net_unload_epbf_rss(n); > + n->rss_data.enabled_software_rss = true; > + } > + > trace_virtio_net_rss_enable(n->rss_data.hash_types, > n->rss_data.indirections_len, > temp.b); > + Unnecessary changes. > return queues; > error: > trace_virtio_net_rss_error(err_msg, err_value); > @@ -1674,7 +1772,7 @@ static ssize_t virtio_net_receive_rcu(NetClientState *nc, const uint8_t *buf, > return -1; > } > > - if (!no_rss && n->rss_data.enabled) { > + if (!no_rss && n->rss_data.enabled && n->rss_data.enabled_software_rss) { > int index = virtio_net_process_rss(nc, buf, size); > if (index >= 0) { > NetClientState *nc2 = qemu_get_subqueue(n->nic, index); > @@ -2780,6 +2878,18 @@ static int virtio_net_post_load_device(void *opaque, int version_id) > } > > if (n->rss_data.enabled) { > + n->rss_data.enabled_software_rss = n->rss_data.populate_hash; > + if (!n->rss_data.populate_hash) { > + if (!virtio_net_load_epbf_rss(n)) { > + if (get_vhost_net(qemu_get_queue(n->nic)->peer)) { > + error_report("Can't post-load eBPF RSS for vhost"); > + } else { > + warn_report("Can't post-load eBPF RSS - fallback to software RSS"); > + n->rss_data.enabled_software_rss = true; > + } > + } > + } btw, I don't see the save and restore of bpf maps, or is it unnecessary? Thanks > + > trace_virtio_net_rss_enable(n->rss_data.hash_types, > n->rss_data.indirections_len, > sizeof(n->rss_data.key)); > @@ -3453,6 +3563,8 @@ static void virtio_net_instance_init(Object *obj) > device_add_bootindex_property(obj, &n->nic_conf.bootindex, > "bootindex", "/ethernet-phy@0", > DEVICE(n)); > + > + ebpf_rss_init(&n->ebpf_rss); > } > > static int virtio_net_pre_save(void *opaque) > diff --git a/include/hw/virtio/virtio-net.h b/include/hw/virtio/virtio-net.h > index f4852ac27b..4d29a577eb 100644 > --- a/include/hw/virtio/virtio-net.h > +++ b/include/hw/virtio/virtio-net.h > @@ -21,6 +21,8 @@ > #include "qemu/option_int.h" > #include "qom/object.h" > > +#include "ebpf/ebpf_rss.h" > + > #define TYPE_VIRTIO_NET "virtio-net-device" > OBJECT_DECLARE_SIMPLE_TYPE(VirtIONet, VIRTIO_NET) > > @@ -130,6 +132,7 @@ typedef struct VirtioNetRscChain { > > typedef struct VirtioNetRssData { > bool enabled; > + bool enabled_software_rss; > bool redirect; > bool populate_hash; > uint32_t hash_types; > @@ -214,6 +217,7 @@ struct VirtIONet { > Notifier migration_state; > VirtioNetRssData rss_data; > struct NetRxPkt *rx_pkt; > + struct EBPFRSSContext ebpf_rss; > }; > > void virtio_net_set_netclient_name(VirtIONet *n, const char *name, > diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c > index 99c476db8c..feb5fa8624 100644 > --- a/net/vhost-vdpa.c > +++ b/net/vhost-vdpa.c > @@ -54,6 +54,8 @@ const int vdpa_feature_bits[] = { > VIRTIO_NET_F_MTU, > VIRTIO_F_IOMMU_PLATFORM, > VIRTIO_F_RING_PACKED, > + VIRTIO_NET_F_RSS, > + VIRTIO_NET_F_HASH_REPORT, > VIRTIO_NET_F_GUEST_ANNOUNCE, > VIRTIO_NET_F_STATUS, > VHOST_INVALID_FEATURE_BIT