| Message ID | 20210114211612.387052-6-andrew@daynix.com |
|---|---|
| State | New |
| Headers | show |
| Series | eBPF RSS support for virtio-net | expand |
On 2021/1/15 上午5:16, Andrew Melnychenko wrote: > From: Andrew <andrew@daynix.com> > > 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 <yuri.benditovich@daynix.com> > Signed-off-by: Andrew Melnychenko <andrew@daynix.com> > --- > hw/net/vhost_net.c | 2 + > hw/net/virtio-net.c | 125 +++++++++++++++++++++++++++++++-- > include/hw/virtio/virtio-net.h | 4 ++ > net/vhost-vdpa.c | 2 + > 4 files changed, 129 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 09ceb02c9d..37016fc73a 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -691,6 +691,19 @@ 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 */ I still think we should not clear feature silently. This may break migraiton if the feature is cleared on destination. > + 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); > + > + return ret; > +} > + > static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features, > Error **errp) > { > @@ -725,9 +738,9 @@ 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 && > @@ -1151,12 +1164,79 @@ static int virtio_net_handle_announce(VirtIONet *n, uint8_t cmd, > } > } > > +static void virtio_net_detach_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; > + > + virtio_net_detach_epbf_rss(n); > +} > + > +static bool virtio_net_attach_ebpf_to_backend(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_attach_epbf_rss(VirtIONet *n) > +{ > + struct EBPFRSSConfig config = {}; > + > + if (!ebpf_rss_is_loaded(&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)) { > + return false; > + } > + > + if (!virtio_net_attach_ebpf_to_backend(n->nic, n->ebpf_rss.program_fd)) { > + return false; > + } > + > + return true; > +} > + > +static void virtio_net_detach_epbf_rss(VirtIONet *n) > +{ > + virtio_net_attach_ebpf_to_backend(n->nic, -1); > +} > + > +static bool virtio_net_load_ebpf(VirtIONet *n) > +{ > + if (!virtio_net_attach_ebpf_to_backend(n->nic, -1)) { > + /* backend does't support steering ebpf */ > + return false; > + } > + > + return ebpf_rss_load(&n->ebpf_rss); > +} > + > +static void virtio_net_unload_ebpf(VirtIONet *n) > +{ > + virtio_net_attach_ebpf_to_backend(n->nic, -1); > + ebpf_rss_unload(&n->ebpf_rss); > } > > static uint16_t virtio_net_handle_rss(VirtIONet *n, > @@ -1271,6 +1351,25 @@ static uint16_t virtio_net_handle_rss(VirtIONet *n, > goto error; > } > n->rss_data.enabled = true; > + > + if (!n->rss_data.populate_hash) { > + if (!virtio_net_attach_epbf_rss(n)) { > + /* EBPF must be loaded for vhost */ > + if (get_vhost_net(qemu_get_queue(n->nic)->peer)) { > + warn_report("Can't load eBPF RSS for vhost"); > + goto error; How about stop the vhost in this case? Thanks
On Fri, Jan 15, 2021 at 9:20 AM Jason Wang <jasowang@redhat.com> wrote: > > > On 2021/1/15 上午5:16, Andrew Melnychenko wrote: > > From: Andrew <andrew@daynix.com> > > > > 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 <yuri.benditovich@daynix.com> > > Signed-off-by: Andrew Melnychenko <andrew@daynix.com> > > --- > > hw/net/vhost_net.c | 2 + > > hw/net/virtio-net.c | 125 +++++++++++++++++++++++++++++++-- > > include/hw/virtio/virtio-net.h | 4 ++ > > net/vhost-vdpa.c | 2 + > > 4 files changed, 129 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 09ceb02c9d..37016fc73a 100644 > > --- a/hw/net/virtio-net.c > > +++ b/hw/net/virtio-net.c > > @@ -691,6 +691,19 @@ 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 */ > > > I still think we should not clear feature silently. This may break > migraiton if the feature is cleared on destination. Do I understand it correctly that if we do not clear features silently and implement a graceful drop to vhost=off when we can't do what we need with vhost - then we do not need to add any migration blocker? > > > > + 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); > > + > > + return ret; > > +} > > + > > static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features, > > Error **errp) > > { > > @@ -725,9 +738,9 @@ 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 && > > @@ -1151,12 +1164,79 @@ static int virtio_net_handle_announce(VirtIONet *n, uint8_t cmd, > > } > > } > > > > +static void virtio_net_detach_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; > > + > > + virtio_net_detach_epbf_rss(n); > > +} > > + > > +static bool virtio_net_attach_ebpf_to_backend(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_attach_epbf_rss(VirtIONet *n) > > +{ > > + struct EBPFRSSConfig config = {}; > > + > > + if (!ebpf_rss_is_loaded(&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)) { > > + return false; > > + } > > + > > + if (!virtio_net_attach_ebpf_to_backend(n->nic, n->ebpf_rss.program_fd)) { > > + return false; > > + } > > + > > + return true; > > +} > > + > > +static void virtio_net_detach_epbf_rss(VirtIONet *n) > > +{ > > + virtio_net_attach_ebpf_to_backend(n->nic, -1); > > +} > > + > > +static bool virtio_net_load_ebpf(VirtIONet *n) > > +{ > > + if (!virtio_net_attach_ebpf_to_backend(n->nic, -1)) { > > + /* backend does't support steering ebpf */ > > + return false; > > + } > > + > > + return ebpf_rss_load(&n->ebpf_rss); > > +} > > + > > +static void virtio_net_unload_ebpf(VirtIONet *n) > > +{ > > + virtio_net_attach_ebpf_to_backend(n->nic, -1); > > + ebpf_rss_unload(&n->ebpf_rss); > > } > > > > static uint16_t virtio_net_handle_rss(VirtIONet *n, > > @@ -1271,6 +1351,25 @@ static uint16_t virtio_net_handle_rss(VirtIONet *n, > > goto error; > > } > > n->rss_data.enabled = true; > > + > > + if (!n->rss_data.populate_hash) { > > + if (!virtio_net_attach_epbf_rss(n)) { > > + /* EBPF must be loaded for vhost */ > > + if (get_vhost_net(qemu_get_queue(n->nic)->peer)) { > > + warn_report("Can't load eBPF RSS for vhost"); > > + goto error; > > > How about stop the vhost in this case? > > Thanks > >
On 2021/1/17 下午5:04, Yuri Benditovich wrote: > On Fri, Jan 15, 2021 at 9:20 AM Jason Wang<jasowang@redhat.com> wrote: >> On 2021/1/15 上午5:16, Andrew Melnychenko wrote: >>> From: Andrew<andrew@daynix.com> >>> >>> 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<yuri.benditovich@daynix.com> >>> Signed-off-by: Andrew Melnychenko<andrew@daynix.com> >>> --- >>> hw/net/vhost_net.c | 2 + >>> hw/net/virtio-net.c | 125 +++++++++++++++++++++++++++++++-- >>> include/hw/virtio/virtio-net.h | 4 ++ >>> net/vhost-vdpa.c | 2 + >>> 4 files changed, 129 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 09ceb02c9d..37016fc73a 100644 >>> --- a/hw/net/virtio-net.c >>> +++ b/hw/net/virtio-net.c >>> @@ -691,6 +691,19 @@ 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 */ >> I still think we should not clear feature silently. This may break >> migraiton if the feature is cleared on destination. > Do I understand it correctly that if we do not clear features silently > and implement a graceful drop to vhost=off when we can't do what we > need with vhost - then we do not need to add any migration blocker? Yes. I think we won't go with migration blocker since we need support migration in the end. Thanks >
Hi Jason, I've prepared a POC of graceful switch to 'vhost off' if respective features are acked by the guest. Such a way we do not need to silently clear RSS and hash report features in case of 'vhost on'. Can you please review it and provide your feedback? I think the only open question is what to do with cases of vhost-user and vhost-vdpa. https://github.com/qemu/qemu/pull/105 This pull request is for reviews only. Thanks in advance On Mon, Jan 18, 2021 at 5:16 AM Jason Wang <jasowang@redhat.com> wrote: > > > On 2021/1/17 下午5:04, Yuri Benditovich wrote: > > On Fri, Jan 15, 2021 at 9:20 AM Jason Wang<jasowang@redhat.com> wrote: > >> On 2021/1/15 上午5:16, Andrew Melnychenko wrote: > >>> From: Andrew<andrew@daynix.com> > >>> > >>> 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<yuri.benditovich@daynix.com> > >>> Signed-off-by: Andrew Melnychenko<andrew@daynix.com> > >>> --- > >>> hw/net/vhost_net.c | 2 + > >>> hw/net/virtio-net.c | 125 +++++++++++++++++++++++++++++++-- > >>> include/hw/virtio/virtio-net.h | 4 ++ > >>> net/vhost-vdpa.c | 2 + > >>> 4 files changed, 129 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 09ceb02c9d..37016fc73a 100644 > >>> --- a/hw/net/virtio-net.c > >>> +++ b/hw/net/virtio-net.c > >>> @@ -691,6 +691,19 @@ 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 */ > >> I still think we should not clear feature silently. This may break > >> migraiton if the feature is cleared on destination. > > Do I understand it correctly that if we do not clear features silently > > and implement a graceful drop to vhost=off when we can't do what we > > need with vhost - then we do not need to add any migration blocker? > > > Yes. I think we won't go with migration blocker since we need support > migration in the end. > > Thanks > > > > >
On Sun, Jan 24, 2021 at 10:24 AM Yuri Benditovich <yuri.benditovich@daynix.com> wrote: > > Hi Jason, > > I've prepared a POC of graceful switch to 'vhost off' if respective > features are acked by the guest. > Such a way we do not need to silently clear RSS and hash report > features in case of 'vhost on'. > Can you please review it and provide your feedback? > > I think the only open question is what to do with cases of vhost-user > and vhost-vdpa. > > https://github.com/qemu/qemu/pull/105 > This pull request is for reviews only. Unfortunately qemu github PR is closed for comments This is the link to the same on Daynix repository https://github.com/daynix/qemu/pull/1 > > Thanks in advance > > > > > > > On Mon, Jan 18, 2021 at 5:16 AM Jason Wang <jasowang@redhat.com> wrote: > > > > > > On 2021/1/17 下午5:04, Yuri Benditovich wrote: > > > On Fri, Jan 15, 2021 at 9:20 AM Jason Wang<jasowang@redhat.com> wrote: > > >> On 2021/1/15 上午5:16, Andrew Melnychenko wrote: > > >>> From: Andrew<andrew@daynix.com> > > >>> > > >>> 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<yuri.benditovich@daynix.com> > > >>> Signed-off-by: Andrew Melnychenko<andrew@daynix.com> > > >>> --- > > >>> hw/net/vhost_net.c | 2 + > > >>> hw/net/virtio-net.c | 125 +++++++++++++++++++++++++++++++-- > > >>> include/hw/virtio/virtio-net.h | 4 ++ > > >>> net/vhost-vdpa.c | 2 + > > >>> 4 files changed, 129 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 09ceb02c9d..37016fc73a 100644 > > >>> --- a/hw/net/virtio-net.c > > >>> +++ b/hw/net/virtio-net.c > > >>> @@ -691,6 +691,19 @@ 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 */ > > >> I still think we should not clear feature silently. This may break > > >> migraiton if the feature is cleared on destination. > > > Do I understand it correctly that if we do not clear features silently > > > and implement a graceful drop to vhost=off when we can't do what we > > > need with vhost - then we do not need to add any migration blocker? > > > > > > Yes. I think we won't go with migration blocker since we need support > > migration in the end. > > > > Thanks > > > > > > > > >
On 2021/1/24 下午4:24, Yuri Benditovich wrote: > Hi Jason, > > I've prepared a POC of graceful switch to 'vhost off' if respective > features are acked by the guest. > Such a way we do not need to silently clear RSS and hash report > features in case of 'vhost on'. > Can you please review it and provide your feedback? > > I think the only open question is what to do with cases of vhost-user > and vhost-vdpa. > > https://github.com/qemu/qemu/pull/105 > This pull request is for reviews only. > > Thanks in advance Will review it sometime this week. Thanks > > > > > > > On Mon, Jan 18, 2021 at 5:16 AM Jason Wang <jasowang@redhat.com> wrote: >> >> On 2021/1/17 下午5:04, Yuri Benditovich wrote: >>> On Fri, Jan 15, 2021 at 9:20 AM Jason Wang<jasowang@redhat.com> wrote: >>>> On 2021/1/15 上午5:16, Andrew Melnychenko wrote: >>>>> From: Andrew<andrew@daynix.com> >>>>> >>>>> 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<yuri.benditovich@daynix.com> >>>>> Signed-off-by: Andrew Melnychenko<andrew@daynix.com> >>>>> --- >>>>> hw/net/vhost_net.c | 2 + >>>>> hw/net/virtio-net.c | 125 +++++++++++++++++++++++++++++++-- >>>>> include/hw/virtio/virtio-net.h | 4 ++ >>>>> net/vhost-vdpa.c | 2 + >>>>> 4 files changed, 129 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 09ceb02c9d..37016fc73a 100644 >>>>> --- a/hw/net/virtio-net.c >>>>> +++ b/hw/net/virtio-net.c >>>>> @@ -691,6 +691,19 @@ 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 */ >>>> I still think we should not clear feature silently. This may break >>>> migraiton if the feature is cleared on destination. >>> Do I understand it correctly that if we do not clear features silently >>> and implement a graceful drop to vhost=off when we can't do what we >>> need with vhost - then we do not need to add any migration blocker? >> >> Yes. I think we won't go with migration blocker since we need support >> migration in the end. >> >> Thanks >> >>
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 09ceb02c9d..37016fc73a 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -691,6 +691,19 @@ 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); + + return ret; +} + static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features, Error **errp) { @@ -725,9 +738,9 @@ 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 && @@ -1151,12 +1164,79 @@ static int virtio_net_handle_announce(VirtIONet *n, uint8_t cmd, } } +static void virtio_net_detach_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; + + virtio_net_detach_epbf_rss(n); +} + +static bool virtio_net_attach_ebpf_to_backend(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_attach_epbf_rss(VirtIONet *n) +{ + struct EBPFRSSConfig config = {}; + + if (!ebpf_rss_is_loaded(&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)) { + return false; + } + + if (!virtio_net_attach_ebpf_to_backend(n->nic, n->ebpf_rss.program_fd)) { + return false; + } + + return true; +} + +static void virtio_net_detach_epbf_rss(VirtIONet *n) +{ + virtio_net_attach_ebpf_to_backend(n->nic, -1); +} + +static bool virtio_net_load_ebpf(VirtIONet *n) +{ + if (!virtio_net_attach_ebpf_to_backend(n->nic, -1)) { + /* backend does't support steering ebpf */ + return false; + } + + return ebpf_rss_load(&n->ebpf_rss); +} + +static void virtio_net_unload_ebpf(VirtIONet *n) +{ + virtio_net_attach_ebpf_to_backend(n->nic, -1); + ebpf_rss_unload(&n->ebpf_rss); } static uint16_t virtio_net_handle_rss(VirtIONet *n, @@ -1271,6 +1351,25 @@ static uint16_t virtio_net_handle_rss(VirtIONet *n, goto error; } n->rss_data.enabled = true; + + if (!n->rss_data.populate_hash) { + if (!virtio_net_attach_epbf_rss(n)) { + /* EBPF must be loaded for vhost */ + 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 detach eBPF if was loaded before */ + virtio_net_detach_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); @@ -1656,7 +1755,7 @@ 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); @@ -2760,6 +2859,18 @@ 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_attach_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; + } + } + } + trace_virtio_net_rss_enable(n->rss_data.hash_types, n->rss_data.indirections_len, sizeof(n->rss_data.key)); @@ -3336,6 +3447,8 @@ static void virtio_net_device_realize(DeviceState *dev, Error **errp) n->qdev = dev; net_rx_pkt_init(&n->rx_pkt, false); + + virtio_net_load_ebpf(n); } static void virtio_net_device_unrealize(DeviceState *dev) @@ -3344,6 +3457,8 @@ static void virtio_net_device_unrealize(DeviceState *dev) VirtIONet *n = VIRTIO_NET(dev); int i, max_queues; + virtio_net_unload_ebpf(n); + /* This will stop vhost backend if appropriate. */ virtio_net_set_status(vdev, 0); @@ -3386,6 +3501,8 @@ 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 7e96d193aa..824a69c23f 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; @@ -209,6 +212,7 @@ 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 fe659ec9e2..8b14215549 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