[RFC PATCH 08/10] qemu_command: Added ebpf RSS helper call for NIC creation.
The helper called before NIC string creation. EBPF fds passed to the child process.
The helper called if qemu supports "ebpf_rss_fds" and returns the helper path.
If libvirt can't retrieve fds from the helper, qemu will be launched
without "ebpf_rss_fds" virtio-net property.
Signed-off-by: Andrew Melnychenko <andrew(a)daynix.com>
---
src/qemu/qemu_command.c | 36 +++++++++++++++++++++++++++++++++++-
src/qemu/qemu_command.h | 2 ++
2 files changed, 37 insertions(+), 1 deletion(-)
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 67a396a513..2fffcee609 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3377,11 +3377,14 @@ qemuBuildNicDevStr(virDomainDef *def,
virDomainNetDef *net,
unsigned int bootindex,
size_t vhostfdSize,
+ char **ebpfRSSfds,
+ size_t ebpfRSSnfds,
virQEMUCaps *qemuCaps)
{
g_auto(virBuffer) buf = VIR_BUFFER_INITIALIZER;
bool usingVirtio = false;
char macaddr[VIR_MAC_STRING_BUFLEN];
+ size_t i = 0;
if (virDomainNetIsVirtioModel(net)) {
if (qemuBuildVirtioDevStr(&buf, "virtio-net", qemuCaps,
@@ -3498,6 +3501,15 @@ qemuBuildNicDevStr(virDomainDef *def,
if (net->driver.virtio.rss == VIR_TRISTATE_SWITCH_ON) {
virBufferAsprintf(&buf, ",rss=%s",
virTristateSwitchTypeToString(net->driver.virtio.rss));
+
+ if (ebpfRSSfds != NULL && ebpfRSSnfds)
+ {
+ virBufferAsprintf(&buf, ",ebpf_rss_fds=");
+ for (i = 0; i < (ebpfRSSnfds - 1); ++i) {
+ virBufferAsprintf(&buf, "%s:",ebpfRSSfds[i]);
+ }
+ virBufferAsprintf(&buf, "%s",ebpfRSSfds[ebpfRSSnfds - 1]);
+ }
}
if (net->driver.virtio.rss_hash_report == VIR_TRISTATE_SWITCH_ON) {
@@ -8492,6 +8504,9 @@ qemuBuildInterfaceCommandLine(virQEMUDriver *driver,
qemuSlirp *slirp;
size_t i;
g_autoptr(virJSONValue) hostnetprops = NULL;
+ char **ebpfRSSfdsName = NULL;
+ int ebpfRSSfds[16] = {};
+ int ebpfRSSnfds = 0;
if (!bootindex)
@@ -8744,8 +8759,20 @@ qemuBuildInterfaceCommandLine(virQEMUDriver *driver,
if (qemuCommandAddExtDevice(cmd, &net->info) < 0)
goto cleanup;
+ if (net->driver.virtio.rss == VIR_TRISTATE_SWITCH_ON
+ && virQEMUCapsGet(qemuCaps, QEMU_CAPS_VIRTIO_EBPF_RSS_FDS)) {
+ ebpfRSSnfds = qemuEbpfRssHelper(virQEMUCapsGetEBPFHelperPath(qemuCaps),
ebpfRSSfds, 16);
+ if (ebpfRSSnfds > 0) {
+ ebpfRSSfdsName = g_new0(char *, ebpfRSSnfds);
+ for (i = 0; i < ebpfRSSnfds; ++i) {
+ ebpfRSSfdsName[i] = g_strdup_printf("%d", ebpfRSSfds[i]);
+ virCommandPassFD(cmd, ebpfRSSfds[i],
VIR_COMMAND_PASS_FD_CLOSE_PARENT);
+ }
+ }
+ }
+
if (!(nic = qemuBuildNicDevStr(def, net, bootindex,
- net->driver.virtio.queues, qemuCaps)))
+ net->driver.virtio.queues, ebpfRSSfdsName,
ebpfRSSnfds, qemuCaps)))
goto cleanup;
virCommandAddArgList(cmd, "-device", nic, NULL);
} else if (!requireNicdev) {
@@ -8785,6 +8812,13 @@ qemuBuildInterfaceCommandLine(virQEMUDriver *driver,
}
VIR_FREE(tapfdName);
VIR_FREE(vhostfd);
+ for (i = 0; ret < 0 && ebpfRSSfds[i] && i < 16; i++) {
+ if (ret < 0)
+ VIR_FORCE_CLOSE(ebpfRSSfds[i]);
+ if (ebpfRSSfdsName)
+ VIR_FREE(ebpfRSSfdsName[i]);
+ }
+ VIR_FREE(ebpfRSSfdsName);
VIR_FREE(tapfd);
VIR_FORCE_CLOSE(vdpafd);
return ret;
diff --git a/src/qemu/qemu_command.h b/src/qemu/qemu_command.h
index 188e63ea1f..cab0bb7770 100644
--- a/src/qemu/qemu_command.h
+++ b/src/qemu/qemu_command.h
@@ -107,6 +107,8 @@ char *qemuBuildNicDevStr(virDomainDef *def,
virDomainNetDef *net,
unsigned int bootindex,
size_t vhostfdSize,
+ char **ebpf_rss_fds,
+ size_t nfds,
virQEMUCaps *qemuCaps);
char *qemuDeviceDriveHostAlias(virDomainDiskDef *disk);
--
2.31.1