Hi all,
On Mon, May 15, 2023 at 12:38 PM Daniel P. Berrangé <berra...@redhat.com> wrote:
>
> On Fri, May 12, 2023 at 03:28:59PM +0300, Andrew Melnychenko wrote:
> > eBPF RSS program and maps may now be passed during initialization.
> > Initially was implemented for libvirt to launch qemu without permissions,
> > and initialized eBPF program through the helper.
> >
> > Signed-off-by: Andrew Melnychenko <and...@daynix.com>
> > ---
> > hw/net/virtio-net.c | 55 ++++++++++++++++++++++++++++++----
> > include/hw/virtio/virtio-net.h | 1 +
> > 2 files changed, 50 insertions(+), 6 deletions(-)
> >
> > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> > index 53e1c326433..a62d7936948 100644
> > --- a/hw/net/virtio-net.c
> > +++ b/hw/net/virtio-net.c
> > @@ -42,6 +42,7 @@
> > #include "sysemu/sysemu.h"
> > #include "trace.h"
> > #include "monitor/qdev.h"
> > +#include "monitor/monitor.h"
> > #include "hw/pci/pci_device.h"
> > #include "net_rx_pkt.h"
> > #include "hw/virtio/vhost.h"
> > @@ -1305,14 +1306,55 @@ 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)
> > +static bool virtio_net_load_ebpf_fds(VirtIONet *n, Error **errp)
> > {
> > - if (!virtio_net_attach_ebpf_to_backend(n->nic, -1)) {
> > - /* backend does't support steering ebpf */
> > - return false;
> > + int fds[EBPF_RSS_MAX_FDS] = { [0 ... EBPF_RSS_MAX_FDS - 1] = -1};
>
> Interesting, I didn't realize this initialization syntax was possible !
>
> > + int nfds = 0;
> > + int ret = true;
> > + int i = 0;
> > + g_autofree char **fds_strs = g_strsplit(n->ebpf_rss_fds, ":", 0)
>
> You can't use 'g_autofree' with 'char **' I'm afraid, as that'll
> merely g_free() the array, but not the individual strings.
>
> Needs to be
>
> g_auto(GStrv) fds_strs
>
> GStrv is a typedef for "char **" which gets g_strfreev() attached
> as its destructor.
Oh yeah, I've missed that! Thank you.
>
>
> > +
> > + ERRP_GUARD();
> > +
> > + if (g_strv_length(fds_strs) != EBPF_RSS_MAX_FDS) {
> > + error_setg(errp,
> > + "Expected %d file descriptors but got %d",
> > + EBPF_RSS_MAX_FDS, g_strv_length(fds_strs));
> > + return false;
> > + }
> > +
> > + for (i = 0; i < nfds; i++) {
> > + fds[i] = monitor_fd_param(monitor_cur(), fds_strs[i], errp);
> > + if (*errp) {
> > + ret = false;
> > + goto exit;
> > + }
> > + }
> > +
> > + ret = ebpf_rss_load_fds(&n->ebpf_rss, fds[0], fds[1], fds[2], fds[3]);
> > +
> > +exit:
> > + if (!ret || *errp) {
> > + for (i = 0; i < nfds && fds[i] != -1; i++) {
> > + close(fds[i]);
> > + }
> > }
> >
> > - return ebpf_rss_load(&n->ebpf_rss);
> > + return ret;
> > +}
> > +
> > +static bool virtio_net_load_ebpf(VirtIONet *n, Error **errp)
> > +{
> > + bool ret = false;
> > +
> > + if (virtio_net_attach_ebpf_to_backend(n->nic, -1)) {
> > + if (!(n->ebpf_rss_fds
> > + && virtio_net_load_ebpf_fds(n, errp))) {
> > + ret = ebpf_rss_load(&n->ebpf_rss);
> > + }
> > + }
> > +
> > + return ret;
> > }
> >
> > static void virtio_net_unload_ebpf(VirtIONet *n)
> > @@ -3738,7 +3780,7 @@ static void virtio_net_device_realize(DeviceState
> > *dev, Error **errp)
> > net_rx_pkt_init(&n->rx_pkt);
> >
> > if (virtio_has_feature(n->host_features, VIRTIO_NET_F_RSS)) {
> > - virtio_net_load_ebpf(n);
> > + virtio_net_load_ebpf(n, errp);
> > }
> > }
> >
> > @@ -3900,6 +3942,7 @@ static Property virtio_net_properties[] = {
> > VIRTIO_NET_F_RSS, false),
> > DEFINE_PROP_BIT64("hash", VirtIONet, host_features,
> > VIRTIO_NET_F_HASH_REPORT, false),
> > + DEFINE_PROP_STRING("ebpf_rss_fds", VirtIONet, ebpf_rss_fds),
> > DEFINE_PROP_BIT64("guest_rsc_ext", VirtIONet, host_features,
> > VIRTIO_NET_F_RSC_EXT, false),
> > DEFINE_PROP_UINT32("rsc_interval", VirtIONet, rsc_timeout,
> > diff --git a/include/hw/virtio/virtio-net.h b/include/hw/virtio/virtio-net.h
> > index ef234ffe7ef..e10ce88f918 100644
> > --- a/include/hw/virtio/virtio-net.h
> > +++ b/include/hw/virtio/virtio-net.h
> > @@ -219,6 +219,7 @@ struct VirtIONet {
> > VirtioNetRssData rss_data;
> > struct NetRxPkt *rx_pkt;
> > struct EBPFRSSContext ebpf_rss;
> > + char *ebpf_rss_fds;
> > };
> >
> > size_t virtio_net_handle_ctrl_iov(VirtIODevice *vdev,
> > --
> > 2.39.1
> >
>
> With regards,
> Daniel
> --
> |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :|
> |: https://libvirt.org -o- https://fstop138.berrange.com :|
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>
