Added new capability ebpf_rss_fds for QEMU.
Added logic for loading the "RSS" eBPF program.
eBPF file descriptors passed to the QEMU.
Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
---
src/qemu/qemu_capabilities.c | 4 +++
src/qemu/qemu_capabilities.h | 3 ++
src/qemu/qemu_command.c | 61 ++++++++++++++++++++++++++++++++++++
src/qemu/qemu_domain.c | 4 +++
src/qemu/qemu_domain.h | 3 ++
5 files changed, 75 insertions(+)
diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index 09bb6ca36e..bb6a587725 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -708,6 +708,9 @@ VIR_ENUM_IMPL(virQEMUCaps,
"usb-mtp", /* QEMU_CAPS_DEVICE_USB_MTP */
"machine.virt.ras", /* QEMU_CAPS_MACHINE_VIRT_RAS */
"virtio-sound", /* QEMU_CAPS_DEVICE_VIRTIO_SOUND */
+
+ /* 460 */
+ "virtio-net.ebpf_rss_fds", /* QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS */
);
@@ -1452,6 +1455,7 @@ static struct virQEMUCapsDevicePropsFlags virQEMUCapsDevicePropsVirtioBlk[] = {
static struct virQEMUCapsDevicePropsFlags virQEMUCapsDevicePropsVirtioNet[] = {
{ "acpi-index", QEMU_CAPS_ACPI_INDEX, NULL },
{ "rss", QEMU_CAPS_VIRTIO_NET_RSS, NULL },
+ { "ebpf-rss-fds", QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS, NULL },
};
static struct virQEMUCapsDevicePropsFlags virQEMUCapsDevicePropsPCIeRootPort[] = {
diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h
index 371ea19bd0..e4bb137b21 100644
--- a/src/qemu/qemu_capabilities.h
+++ b/src/qemu/qemu_capabilities.h
@@ -688,6 +688,9 @@ typedef enum { /* virQEMUCapsFlags grouping marker for syntax-check */
QEMU_CAPS_MACHINE_VIRT_RAS, /* -machine virt,ras= */
QEMU_CAPS_DEVICE_VIRTIO_SOUND, /* -device virtio-sound-* */
+ /* 460 */
+ QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS, /* virtio-net ebpf_rss_fds feature */
+
QEMU_CAPS_LAST /* this must always be the last item */
} virQEMUCapsFlags;
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 9859ea67a4..77715cf6fe 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3805,6 +3805,25 @@ qemuBuildLegacyNicStr(virDomainNetDef *net)
}
+static virJSONValue *
+qemuBuildEbpfRssArg(virDomainNetDef *net)
+{
+ qemuDomainNetworkPrivate *netpriv = QEMU_DOMAIN_NETWORK_PRIVATE(net);
+ g_autoptr(virJSONValue) props = NULL;
+
+ GSList *n;
+
+ if (netpriv->ebpfrssfds)
+ props = virJSONValueNewArray();
+
+ for (n = netpriv->ebpfrssfds; n; n = n->next) {
+ virJSONValueArrayAppendString(props, qemuFDPassDirectGetPath(n->data));
+ }
+
+ return g_steal_pointer(&props);
+}
+
+
virJSONValue *
qemuBuildNicDevProps(virDomainDef *def,
virDomainNetDef *net,
@@ -3813,6 +3832,7 @@ qemuBuildNicDevProps(virDomainDef *def,
g_autoptr(virJSONValue) props = NULL;
char macaddr[VIR_MAC_STRING_BUFLEN];
g_autofree char *netdev = g_strdup_printf("host%s", net->info.alias);
+ g_autoptr(virJSONValue) ebpffds = NULL;
if (virDomainNetIsVirtioModel(net)) {
const char *tx = NULL;
@@ -3863,6 +3883,8 @@ qemuBuildNicDevProps(virDomainDef *def,
if (!(props = qemuBuildVirtioDevProps(VIR_DOMAIN_DEVICE_NET, net, qemuCaps)))
return NULL;
+ ebpffds = qemuBuildEbpfRssArg(net);
+
if (virJSONValueObjectAdd(&props,
"S:tx", tx,
"T:ioeventfd", net->driver.virtio.ioeventfd,
@@ -3887,6 +3909,7 @@ qemuBuildNicDevProps(virDomainDef *def,
"T:hash", net->driver.virtio.rss_hash_report,
"p:host_mtu", net->mtu,
"T:failover", failover,
+ "A:ebpf-rss-fds", &ebpffds,
NULL) < 0)
return NULL;
} else {
@@ -4170,6 +4193,39 @@ qemuBuildWatchdogDevProps(const virDomainDef *def,
}
+static void
+qemuOpenEbpfRssFds(virDomainNetDef *net, virQEMUCaps *qemuCaps)
+{
+ const char *ebpfRSSObject = NULL;
+ int fds[16];
+ int nfds = 0;
+ size_t i = 0;
+ qemuDomainNetworkPrivate *netpriv = QEMU_DOMAIN_NETWORK_PRIVATE(net);
+
+ netpriv->libbpfRSSObject = NULL;
+ netpriv->ebpfrssfds = NULL;
+
+ /* Add ebpf values */
+ if (net->driver.virtio.rss == VIR_TRISTATE_SWITCH_ON
+ && net->driver.virtio.rss_hash_report != VIR_TRISTATE_SWITCH_ON
+ && virQEMUCapsGet(qemuCaps, QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS)) {
+ ebpfRSSObject = virQEMUCapsGetEbpf(qemuCaps, "rss");
+ nfds = qemuInterfaceLoadEbpf(ebpfRSSObject, &netpriv->libbpfRSSObject, fds, 16);
+
+ if (nfds > 0) {
+ for (i = 0; i < nfds; ++i) {
+ g_autofree char *name = g_strdup_printf("ebpfrssfd-%s-%zu", net->info.alias, i);
+
+ netpriv->ebpfrssfds =
+ g_slist_prepend(netpriv->ebpfrssfds, qemuFDPassDirectNew(name, fds + i));
+ }
+ }
+
+ netpriv->ebpfrssfds = g_slist_reverse(netpriv->ebpfrssfds);
+ }
+}
+
+
static int
qemuBuildWatchdogCommandLine(virCommand *cmd,
const virDomainDef *def,
@@ -8725,6 +8781,7 @@ qemuBuildInterfaceCommandLine(virQEMUDriver *driver,
g_autoptr(virJSONValue) hostnetprops = NULL;
qemuDomainNetworkPrivate *netpriv = QEMU_DOMAIN_NETWORK_PRIVATE(net);
GSList *n;
+ g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
if (qemuDomainValidateActualNetDef(net, qemuCaps) < 0)
return -1;
@@ -8860,6 +8917,10 @@ qemuBuildInterfaceCommandLine(virQEMUDriver *driver,
qemuFDPassDirectTransferCommand(netpriv->slirpfd, cmd);
qemuFDPassTransferCommand(netpriv->vdpafd, cmd);
+ qemuOpenEbpfRssFds(net, qemuCaps);
+ for (n = netpriv->ebpfrssfds; n; n = n->next)
+ qemuFDPassDirectTransferCommand(n->data, cmd);
+
if (!(hostnetprops = qemuBuildHostNetProps(vm, net)))
goto cleanup;
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index bda62f2e5c..894a6af348 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -38,6 +38,7 @@
#include "qemu_checkpoint.h"
#include "qemu_validate.h"
#include "qemu_namespace.h"
+#include "qemu_interface.h"
#include "viralloc.h"
#include "virlog.h"
#include "virerror.h"
@@ -1079,6 +1080,7 @@ qemuDomainNetworkPrivateClearFDs(qemuDomainNetworkPrivate *priv)
g_clear_pointer(&priv->vdpafd, qemuFDPassFree);
g_slist_free_full(g_steal_pointer(&priv->vhostfds), (GDestroyNotify) qemuFDPassDirectFree);
g_slist_free_full(g_steal_pointer(&priv->tapfds), (GDestroyNotify) qemuFDPassDirectFree);
+ g_slist_free_full(g_steal_pointer(&priv->ebpfrssfds), (GDestroyNotify) qemuFDPassDirectFree);
}
@@ -1090,6 +1092,8 @@ qemuDomainNetworkPrivateDispose(void *obj G_GNUC_UNUSED)
qemuSlirpFree(priv->slirp);
qemuDomainNetworkPrivateClearFDs(priv);
+
+ qemuInterfaceCloseEbpf(priv->libbpfRSSObject);
}
diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
index a3089ea449..d15789f9ac 100644
--- a/src/qemu/qemu_domain.h
+++ b/src/qemu/qemu_domain.h
@@ -434,6 +434,9 @@ struct _qemuDomainNetworkPrivate {
GSList *tapfds; /* qemuFDPassDirect */
GSList *vhostfds; /* qemuFDPassDirect */
qemuFDPass *vdpafd;
+
+ void *libbpfRSSObject;
+ GSList *ebpfrssfds; /* qemuFDPassDirect eBPF RSS fds from helper */
};
--
2.44.0
_______________________________________________
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On 5/12/24 21:45, Andrew Melnychenko wrote:
> Added new capability ebpf_rss_fds for QEMU.
> Added logic for loading the "RSS" eBPF program.
> eBPF file descriptors passed to the QEMU.
>
> Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
> ---
> src/qemu/qemu_capabilities.c | 4 +++
> src/qemu/qemu_capabilities.h | 3 ++
> src/qemu/qemu_command.c | 61 ++++++++++++++++++++++++++++++++++++
> src/qemu/qemu_domain.c | 4 +++
> src/qemu/qemu_domain.h | 3 ++
> 5 files changed, 75 insertions(+)
>
> diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
> index 09bb6ca36e..bb6a587725 100644
> --- a/src/qemu/qemu_capabilities.c
> +++ b/src/qemu/qemu_capabilities.c
> @@ -708,6 +708,9 @@ VIR_ENUM_IMPL(virQEMUCaps,
> "usb-mtp", /* QEMU_CAPS_DEVICE_USB_MTP */
> "machine.virt.ras", /* QEMU_CAPS_MACHINE_VIRT_RAS */
> "virtio-sound", /* QEMU_CAPS_DEVICE_VIRTIO_SOUND */
> +
> + /* 460 */
> + "virtio-net.ebpf_rss_fds", /* QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS */
> );
>
>
> @@ -1452,6 +1455,7 @@ static struct virQEMUCapsDevicePropsFlags virQEMUCapsDevicePropsVirtioBlk[] = {
> static struct virQEMUCapsDevicePropsFlags virQEMUCapsDevicePropsVirtioNet[] = {
> { "acpi-index", QEMU_CAPS_ACPI_INDEX, NULL },
> { "rss", QEMU_CAPS_VIRTIO_NET_RSS, NULL },
> + { "ebpf-rss-fds", QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS, NULL },
> };
>
> static struct virQEMUCapsDevicePropsFlags virQEMUCapsDevicePropsPCIeRootPort[] = {
> diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h
> index 371ea19bd0..e4bb137b21 100644
> --- a/src/qemu/qemu_capabilities.h
> +++ b/src/qemu/qemu_capabilities.h
> @@ -688,6 +688,9 @@ typedef enum { /* virQEMUCapsFlags grouping marker for syntax-check */
> QEMU_CAPS_MACHINE_VIRT_RAS, /* -machine virt,ras= */
> QEMU_CAPS_DEVICE_VIRTIO_SOUND, /* -device virtio-sound-* */
>
> + /* 460 */
> + QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS, /* virtio-net ebpf_rss_fds feature */
> +
> QEMU_CAPS_LAST /* this must always be the last item */
> } virQEMUCapsFlags;
>
> diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
> index 9859ea67a4..77715cf6fe 100644
> --- a/src/qemu/qemu_command.c
> +++ b/src/qemu/qemu_command.c
> @@ -3805,6 +3805,25 @@ qemuBuildLegacyNicStr(virDomainNetDef *net)
> }
>
>
> +static virJSONValue *
> +qemuBuildEbpfRssArg(virDomainNetDef *net)
> +{
> + qemuDomainNetworkPrivate *netpriv = QEMU_DOMAIN_NETWORK_PRIVATE(net);
> + g_autoptr(virJSONValue) props = NULL;
> +
> + GSList *n;
> +
> + if (netpriv->ebpfrssfds)
> + props = virJSONValueNewArray();
nitpick: A bit more convoluted than needed be.
if (!netpriv->ebpfrssfds)
return NULL;
props = virJSONValueNewArray();
> +
> + for (n = netpriv->ebpfrssfds; n; n = n->next) {
> + virJSONValueArrayAppendString(props, qemuFDPassDirectGetPath(n->data));
> + }
> +
> + return g_steal_pointer(&props);
> +}
> +
> +
> virJSONValue *
> qemuBuildNicDevProps(virDomainDef *def,
> virDomainNetDef *net,
> @@ -3813,6 +3832,7 @@ qemuBuildNicDevProps(virDomainDef *def,
> g_autoptr(virJSONValue) props = NULL;
> char macaddr[VIR_MAC_STRING_BUFLEN];
> g_autofree char *netdev = g_strdup_printf("host%s", net->info.alias);
> + g_autoptr(virJSONValue) ebpffds = NULL;
We like to declare variables in their smallest possible scope. IOW, this
should be declared ..
>
> if (virDomainNetIsVirtioModel(net)) {
> const char *tx = NULL;
.. in this block.
> @@ -3863,6 +3883,8 @@ qemuBuildNicDevProps(virDomainDef *def,
> if (!(props = qemuBuildVirtioDevProps(VIR_DOMAIN_DEVICE_NET, net, qemuCaps)))
> return NULL;
>
> + ebpffds = qemuBuildEbpfRssArg(net);
> +
> if (virJSONValueObjectAdd(&props,
> "S:tx", tx,
> "T:ioeventfd", net->driver.virtio.ioeventfd,
> @@ -3887,6 +3909,7 @@ qemuBuildNicDevProps(virDomainDef *def,
> "T:hash", net->driver.virtio.rss_hash_report,
> "p:host_mtu", net->mtu,
> "T:failover", failover,
> + "A:ebpf-rss-fds", &ebpffds,
> NULL) < 0)
> return NULL;
> } else {
> @@ -4170,6 +4193,39 @@ qemuBuildWatchdogDevProps(const virDomainDef *def,
> }
>
>
> +static void
> +qemuOpenEbpfRssFds(virDomainNetDef *net, virQEMUCaps *qemuCaps)
> +{
> + const char *ebpfRSSObject = NULL;
> + int fds[16];
So there can be 16 FDs top? Isn't the actual value related to number of
virtio queues?
> + int nfds = 0;
> + size_t i = 0;
> + qemuDomainNetworkPrivate *netpriv = QEMU_DOMAIN_NETWORK_PRIVATE(net);
> +
> + netpriv->libbpfRSSObject = NULL;
> + netpriv->ebpfrssfds = NULL;
This looks suspicious. When allocating private data, g_new0() made sure
this is zeroed out.
> +
> + /* Add ebpf values */
> + if (net->driver.virtio.rss == VIR_TRISTATE_SWITCH_ON
> + && net->driver.virtio.rss_hash_report != VIR_TRISTATE_SWITCH_ON
> + && virQEMUCapsGet(qemuCaps, QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS)) {
> + ebpfRSSObject = virQEMUCapsGetEbpf(qemuCaps, "rss");
> + nfds = qemuInterfaceLoadEbpf(ebpfRSSObject, &netpriv->libbpfRSSObject, fds, 16);
s/G_N_ELEMENTS(fds)/16/
Also, at this point if nfds == -1 we're not sure whether we're lacking
libbpf, or libpf failed to load eBPF program. While the former should be
skipped over, the latter is a fatal error, isn't it?
> +
> + if (nfds > 0) {
To increase readability of this code (by decrasing level of nesting),
I'd write this as:
if (nfds <= 0)
return;
> + for (i = 0; i < nfds; ++i) {
> + g_autofree char *name = g_strdup_printf("ebpfrssfd-%s-%zu", net->info.alias, i);
> +
> + netpriv->ebpfrssfds =
> + g_slist_prepend(netpriv->ebpfrssfds, qemuFDPassDirectNew(name, fds + i));
> + }
> + }
> +
> + netpriv->ebpfrssfds = g_slist_reverse(netpriv->ebpfrssfds);
> + }
> +}
> +
> +
Michal
Hi all,
On Fri, May 17, 2024 at 5:00 PM Michal Prívozník <mprivozn@redhat.com> wrote:
>
> On 5/12/24 21:45, Andrew Melnychenko wrote:
> > Added new capability ebpf_rss_fds for QEMU.
> > Added logic for loading the "RSS" eBPF program.
> > eBPF file descriptors passed to the QEMU.
> >
> > Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
> > ---
> > src/qemu/qemu_capabilities.c | 4 +++
> > src/qemu/qemu_capabilities.h | 3 ++
> > src/qemu/qemu_command.c | 61 ++++++++++++++++++++++++++++++++++++
> > src/qemu/qemu_domain.c | 4 +++
> > src/qemu/qemu_domain.h | 3 ++
> > 5 files changed, 75 insertions(+)
> >
> > diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
> > index 09bb6ca36e..bb6a587725 100644
> > --- a/src/qemu/qemu_capabilities.c
> > +++ b/src/qemu/qemu_capabilities.c
> > @@ -708,6 +708,9 @@ VIR_ENUM_IMPL(virQEMUCaps,
> > "usb-mtp", /* QEMU_CAPS_DEVICE_USB_MTP */
> > "machine.virt.ras", /* QEMU_CAPS_MACHINE_VIRT_RAS */
> > "virtio-sound", /* QEMU_CAPS_DEVICE_VIRTIO_SOUND */
> > +
> > + /* 460 */
> > + "virtio-net.ebpf_rss_fds", /* QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS */
> > );
> >
> >
> > @@ -1452,6 +1455,7 @@ static struct virQEMUCapsDevicePropsFlags virQEMUCapsDevicePropsVirtioBlk[] = {
> > static struct virQEMUCapsDevicePropsFlags virQEMUCapsDevicePropsVirtioNet[] = {
> > { "acpi-index", QEMU_CAPS_ACPI_INDEX, NULL },
> > { "rss", QEMU_CAPS_VIRTIO_NET_RSS, NULL },
> > + { "ebpf-rss-fds", QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS, NULL },
> > };
> >
> > static struct virQEMUCapsDevicePropsFlags virQEMUCapsDevicePropsPCIeRootPort[] = {
> > diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h
> > index 371ea19bd0..e4bb137b21 100644
> > --- a/src/qemu/qemu_capabilities.h
> > +++ b/src/qemu/qemu_capabilities.h
> > @@ -688,6 +688,9 @@ typedef enum { /* virQEMUCapsFlags grouping marker for syntax-check */
> > QEMU_CAPS_MACHINE_VIRT_RAS, /* -machine virt,ras= */
> > QEMU_CAPS_DEVICE_VIRTIO_SOUND, /* -device virtio-sound-* */
> >
> > + /* 460 */
> > + QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS, /* virtio-net ebpf_rss_fds feature */
> > +
> > QEMU_CAPS_LAST /* this must always be the last item */
> > } virQEMUCapsFlags;
> >
> > diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
> > index 9859ea67a4..77715cf6fe 100644
> > --- a/src/qemu/qemu_command.c
> > +++ b/src/qemu/qemu_command.c
> > @@ -3805,6 +3805,25 @@ qemuBuildLegacyNicStr(virDomainNetDef *net)
> > }
> >
> >
> > +static virJSONValue *
> > +qemuBuildEbpfRssArg(virDomainNetDef *net)
> > +{
> > + qemuDomainNetworkPrivate *netpriv = QEMU_DOMAIN_NETWORK_PRIVATE(net);
> > + g_autoptr(virJSONValue) props = NULL;
> > +
> > + GSList *n;
> > +
> > + if (netpriv->ebpfrssfds)
> > + props = virJSONValueNewArray();
>
> nitpick: A bit more convoluted than needed be.
>
> if (!netpriv->ebpfrssfds)
> return NULL;
>
> props = virJSONValueNewArray();
>
I'll refactor it in the next patch.
> > +
> > + for (n = netpriv->ebpfrssfds; n; n = n->next) {
> > + virJSONValueArrayAppendString(props, qemuFDPassDirectGetPath(n->data));
> > + }
> > +
> > + return g_steal_pointer(&props);
> > +}
> > +
> > +
> > virJSONValue *
> > qemuBuildNicDevProps(virDomainDef *def,
> > virDomainNetDef *net,
> > @@ -3813,6 +3832,7 @@ qemuBuildNicDevProps(virDomainDef *def,
> > g_autoptr(virJSONValue) props = NULL;
> > char macaddr[VIR_MAC_STRING_BUFLEN];
> > g_autofree char *netdev = g_strdup_printf("host%s", net->info.alias);
> > + g_autoptr(virJSONValue) ebpffds = NULL;
>
> We like to declare variables in their smallest possible scope. IOW, this
> should be declared ..
>
> >
> > if (virDomainNetIsVirtioModel(net)) {
> > const char *tx = NULL;
>
> .. in this block.
Ok.
> > @@ -3863,6 +3883,8 @@ qemuBuildNicDevProps(virDomainDef *def,
> > if (!(props = qemuBuildVirtioDevProps(VIR_DOMAIN_DEVICE_NET, net, qemuCaps)))
> > return NULL;
> >
> > + ebpffds = qemuBuildEbpfRssArg(net);
> > +
> > if (virJSONValueObjectAdd(&props,
> > "S:tx", tx,
> > "T:ioeventfd", net->driver.virtio.ioeventfd,
> > @@ -3887,6 +3909,7 @@ qemuBuildNicDevProps(virDomainDef *def,
> > "T:hash", net->driver.virtio.rss_hash_report,
> > "p:host_mtu", net->mtu,
> > "T:failover", failover,
> > + "A:ebpf-rss-fds", &ebpffds,
> > NULL) < 0)
> > return NULL;
> > } else {
> > @@ -4170,6 +4193,39 @@ qemuBuildWatchdogDevProps(const virDomainDef *def,
> > }
> >
> >
> > +static void
> > +qemuOpenEbpfRssFds(virDomainNetDef *net, virQEMUCaps *qemuCaps)
> > +{
> > + const char *ebpfRSSObject = NULL;
> > + int fds[16];
>
> So there can be 16 FDs top? Isn't the actual value related to number of
> virtio queues?
The 16 is just a "big enough number". Overall, I think it is possible to
dynamically figure out or allocate filedescriptors - I'll check it in
the next patches.
>
> > + int nfds = 0;
> > + size_t i = 0;
> > + qemuDomainNetworkPrivate *netpriv = QEMU_DOMAIN_NETWORK_PRIVATE(net);
> > +
> > + netpriv->libbpfRSSObject = NULL;
> > + netpriv->ebpfrssfds = NULL;
>
> This looks suspicious. When allocating private data, g_new0() made sure
> this is zeroed out.
>
> > +
> > + /* Add ebpf values */
> > + if (net->driver.virtio.rss == VIR_TRISTATE_SWITCH_ON
> > + && net->driver.virtio.rss_hash_report != VIR_TRISTATE_SWITCH_ON
> > + && virQEMUCapsGet(qemuCaps, QEMU_CAPS_VIRTIO_NET_EBPF_RSS_FDS)) {
> > + ebpfRSSObject = virQEMUCapsGetEbpf(qemuCaps, "rss");
> > + nfds = qemuInterfaceLoadEbpf(ebpfRSSObject, &netpriv->libbpfRSSObject, fds, 16);
>
> s/G_N_ELEMENTS(fds)/16/
>
> Also, at this point if nfds == -1 we're not sure whether we're lacking
> libbpf, or libpf failed to load eBPF program. While the former should be
> skipped over, the latter is a fatal error, isn't it?
I'll check it.
>
> > +
> > + if (nfds > 0) {
>
> To increase readability of this code (by decrasing level of nesting),
> I'd write this as:
>
> if (nfds <= 0)
> return;
>
> > + for (i = 0; i < nfds; ++i) {
> > + g_autofree char *name = g_strdup_printf("ebpfrssfd-%s-%zu", net->info.alias, i);
> > +
> > + netpriv->ebpfrssfds =
> > + g_slist_prepend(netpriv->ebpfrssfds, qemuFDPassDirectNew(name, fds + i));
> > + }
> > + }
> > +
> > + netpriv->ebpfrssfds = g_slist_reverse(netpriv->ebpfrssfds);
> > + }
> > +}
> > +
> > +
>
> Michal
>
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