Re: [PATCH v2 1/4] domain_conf: Added configs for RSS and Hash report.

Added "rss" and "rss_hash_report" configuration that should be used with qemu virtio RSS. Both options are triswitches. Used as "driver" options and affects only NIC with model type "virtio". In other patches - options should turn on virtio-net RSS and hash properties. Signed-off-by: Andrew Melnychenko <andrew(a)daynix.com&gt; --- docs/formatdomain.rst | 18 ++++++++++++++++++ docs/schemas/domaincommon.rng | 10 ++++++++++ src/conf/domain_conf.c | 31 ++++++++++++++++++++++++++++++- src/conf/domain_conf.h | 2 ++ 4 files changed, 60 insertions(+), 1 deletion(-) diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst index d4f30bb8af..ce3e8a5dbf 100644 --- a/docs/formatdomain.rst +++ b/docs/formatdomain.rst @@ -5305,6 +5305,24 @@ following attributes are available for the ``"virtio"`` NIC driver: only for ``vhostuser`` type. :since:`Since 3.7.0 (QEMU and KVM only)` **In general you should leave this option alone, unless you are very certain you know what you are doing.** +``rss`` + The ``rss`` option enables in-qemu/ebpf RSS for virtio NIC. RSS works with + virtio and tap backends only. Virtio NIC will be launched with "rss" + property. For now "in-qemu" RSS is supported by libvirt. + QEMU may load eBPF RSS if it has CAP_SYS_ADMIN permissions, which is + not supported by default in libvirt. + **In general you should leave this option alone, unless you are very certain + you know what you are doing. Proper RSS configuration depends from vcpu, + tap, and vhost settings.** +``rss_hash_report`` + The ``rss_hash_report`` option enables in-qemu RSS hash report for virtio + NIC. Virtio NIC will be launched with a "hash" property. Network packets provided + to VM will contain a hash of the packet in the virt header. Usually enabled + alongside with ``rss``. Without ``rss`` option, the hash report doesn't affect + steering itself but provides vnet header with a calculated hash. + **In general you should leave this option alone, unless you are very certain + you know what you are doing. Proper RSS configuration depends from vcpu, + tap, and vhost settings.** virtio options For virtio interfaces, `Virtio-specific options <#elementsVirtio>`__ can also be set. ( :since:`Since 3.5.0` ) diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng index 7fa5c2b8b5..9b5b94fc6c 100644 --- a/docs/schemas/domaincommon.rng +++ b/docs/schemas/domaincommon.rng @@ -3595,6 +3595,16 @@ </optional> </element> </optional> + <optional> + <attribute name="rss"> + <ref name="virOnOff"/> + </attribute> + </optional> + <optional> + <attribute name="rss_hash_report"> + <ref name="virOnOff"/> + </attribute> + </optional> </interleave> </element> </optional> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index 716c6d2240..762987e8a9 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -10271,6 +10271,8 @@ virDomainNetDefParseXML(virDomainXMLOption *xmlopt, g_autofree char *vhost_path = NULL; g_autofree char *tap = NULL; g_autofree char *vhost = NULL; + g_autofree char *virtio_rss = NULL; + g_autofree char *virtio_rss_hash_report = NULL; const char *prefix = xmlopt ? xmlopt->config.netPrefix : NULL; if (!(def = virDomainNetDefNew(xmlopt))) @@ -10412,6 +10414,8 @@ virDomainNetDefParseXML(virDomainXMLOption *xmlopt, queues = virXMLPropString(driver_node, "queues"); rx_queue_size = virXMLPropString(driver_node, "rx_queue_size"); tx_queue_size = virXMLPropString(driver_node, "tx_queue_size"); + virtio_rss = virXMLPropString(driver_node, "rss"); + virtio_rss_hash_report = virXMLPropString(driver_node, "rss_hash_report"); if ((filterref_node = virXPathNode("./filterref", ctxt))) { filter = virXMLPropString(filterref_node, "filter"); @@ -10822,7 +10826,24 @@ virDomainNetDefParseXML(virDomainXMLOption *xmlopt, } def->driver.virtio.tx_queue_size = q; } - + if (virtio_rss) { + if ((val = virTristateSwitchTypeFromString(virtio_rss)) <= 0) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + _("'rss' attribute must be 'on'/'off'/'default': %s"), + virtio_rss); + goto error; + } + def->driver.virtio.rss = val; + } + if (virtio_rss_hash_report) { + if ((val = virTristateSwitchTypeFromString(virtio_rss_hash_report)) <= 0) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, + _("'rss_hash_report' attribute must be 'on'/'off'/'default': %s"), + virtio_rss_hash_report); + goto error; + } + def->driver.virtio.rss_hash_report = val; + } if ((tmpNode = virXPathNode("./driver/host", ctxt))) { if (virXMLPropTristateSwitch(tmpNode, "csum", VIR_XML_PROP_NONE, &def->driver.virtio.host.csum) < 0)