From: Michal Privoznik Date: Thu, 18 Aug 2016 16:19:13 +0000 (+0200) Subject: conf: Add support for virtio-net.rx_queue_size X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=c56cdf25935e0e7fe6b0e803d62fec223b9a0df2;p=libvirt.git conf: Add support for virtio-net.rx_queue_size https://bugzilla.redhat.com/show_bug.cgi?id=1366989 QEMU added another virtio-net tunable [1]. It basically allows users to set the size of RX virtio ring. But because virtio-net uses two separate ring buffers to pass data from/to guest they named it explicitly rx_queue_size. We should expose it in our XML too. 1: http://lists.nongnu.org/archive/html/qemu-devel/2016-08/msg02029.html Signed-off-by: Michal Privoznik --- diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in index feaeaa24b9..f48a4d8b81 100644 --- a/docs/formatdomain.html.in +++ b/docs/formatdomain.html.in @@ -4674,7 +4674,7 @@ qemu-kvm -net nic,model=? /dev/null <source network='default'/> <target dev='vnet1'/> <model type='virtio'/> - <driver name='vhost' txmode='iothread' ioeventfd='on' event_idx='off' queues='5'> + <driver name='vhost' txmode='iothread' ioeventfd='on' event_idx='off' queues='5' rx_queue_size='256'> <host csum='off' gso='off' tso4='off' tso6='off' ecn='off' ufo='off' mrg_rxbuf='off'/> <guest csum='off' tso4='off' tso6='off' ecn='off' ufo='off'/> </driver> @@ -4790,6 +4790,20 @@ qemu-kvm -net nic,model=? /dev/null virtio-net since 1.0.6 (QEMU and KVM only) vhost-user since 1.2.17 (QEMU and KVM only) +
rx_queue_size
+
+ The optional rx_queue_size attribute controls + the size of virtio ring for each queue as described above. + The default value is hypervisor dependent and may change + across its releases. Moreover, some hypervisors may pose + some restrictions on actual value. For instance, latest + QEMU (as of 2016-09-01) requires value to be a power of two + from [256, 1024] range. + Since 2.3.0 (QEMU and KVM only)

+ + In general you should leave this option alone, unless you + are very certain you know what you are doing. +

Offloading options for the host and guest can be configured using diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng index af32df8306..8aaa67e111 100644 --- a/docs/schemas/domaincommon.rng +++ b/docs/schemas/domaincommon.rng @@ -2557,6 +2557,11 @@ + + + + + diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index db030cc001..0828041dd8 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -8981,6 +8981,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt, char *ioeventfd = NULL; char *event_idx = NULL; char *queues = NULL; + char *rx_queue_size = NULL; char *str = NULL; char *filter = NULL; char *internal = NULL; @@ -9153,6 +9154,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt, ioeventfd = virXMLPropString(cur, "ioeventfd"); event_idx = virXMLPropString(cur, "event_idx"); queues = virXMLPropString(cur, "queues"); + rx_queue_size = virXMLPropString(cur, "rx_queue_size"); } else if (xmlStrEqual(cur->name, BAD_CAST "filterref")) { if (filter) { virReportError(VIR_ERR_XML_ERROR, "%s", @@ -9536,6 +9538,16 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt, if (q > 1) def->driver.virtio.queues = q; } + if (rx_queue_size) { + unsigned int q; + if (virStrToLong_uip(rx_queue_size, NULL, 10, &q) < 0) { + virReportError(VIR_ERR_XML_DETAIL, + _("'rx_queue_size' attribute must be positive number: %s"), + rx_queue_size); + goto error; + } + def->driver.virtio.rx_queue_size = q; + } if ((str = virXPathString("string(./driver/host/@csum)", ctxt))) { if ((val = virTristateSwitchTypeFromString(str)) <= 0) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, @@ -9716,6 +9728,7 @@ virDomainNetDefParseXML(virDomainXMLOptionPtr xmlopt, VIR_FREE(ioeventfd); VIR_FREE(event_idx); VIR_FREE(queues); + VIR_FREE(rx_queue_size); VIR_FREE(str); VIR_FREE(filter); VIR_FREE(type); @@ -20919,6 +20932,9 @@ virDomainVirtioNetDriverFormat(char **outstr, } if (def->driver.virtio.queues) virBufferAsprintf(&buf, "queues='%u' ", def->driver.virtio.queues); + if (def->driver.virtio.rx_queue_size) + virBufferAsprintf(&buf, "rx_queue_size='%u' ", + def->driver.virtio.rx_queue_size); virBufferTrim(&buf, " ", -1); diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h index 3a55927487..c14a39c439 100644 --- a/src/conf/domain_conf.h +++ b/src/conf/domain_conf.h @@ -906,6 +906,7 @@ struct _virDomainNetDef { virTristateSwitch ioeventfd; virTristateSwitch event_idx; unsigned int queues; /* Multiqueue virtio-net */ + unsigned int rx_queue_size; struct { virTristateSwitch csum; virTristateSwitch gso; diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 7fce2fcb9f..6c57ed2c62 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -2475,6 +2475,13 @@ qemuDomainDeviceDefValidate(const virDomainDeviceDef *dev, "not supported by QEMU")); goto cleanup; } + + if (STREQ_NULLABLE(net->model, "virtio") && + net->driver.virtio.rx_queue_size & (net->driver.virtio.rx_queue_size - 1)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("rx_queue_size has to be a power of two")); + goto cleanup; + } } ret = 0; diff --git a/tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize-invalid-size.xml b/tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize-invalid-size.xml new file mode 100644 index 0000000000..d308bc1a62 --- /dev/null +++ b/tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize-invalid-size.xml @@ -0,0 +1,29 @@ + + QEMUGuest1 + c7a5fdbd-edaf-9455-926a-d65c16db1809 + 219100 + 219100 + 1 + + hvm + + + + destroy + restart + destroy + + /usr/bin/qemu + + + + + + + + + + + + + diff --git a/tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize.xml b/tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize.xml new file mode 100644 index 0000000000..cfb4742fc6 --- /dev/null +++ b/tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize.xml @@ -0,0 +1,29 @@ + + QEMUGuest1 + c7a5fdbd-edaf-9455-926a-d65c16db1809 + 219100 + 219100 + 1 + + hvm + + + + destroy + restart + destroy + + /usr/bin/qemu + + + + + + + + + + + + + diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c index 7717ed896b..0493acc731 100644 --- a/tests/qemuxml2argvtest.c +++ b/tests/qemuxml2argvtest.c @@ -1047,6 +1047,7 @@ mymain(void) QEMU_CAPS_VIRTIO_S390); DO_TEST("net-virtio-ccw", QEMU_CAPS_VIRTIO_CCW, QEMU_CAPS_VIRTIO_S390); + DO_TEST_PARSE_ERROR("net-virtio-rxqueuesize-invalid-size", NONE); DO_TEST("net-eth", NONE); DO_TEST("net-eth-ifname", NONE); DO_TEST("net-eth-names", NONE); diff --git a/tests/qemuxml2xmloutdata/qemuxml2xmlout-net-virtio-rxqueuesize.xml b/tests/qemuxml2xmloutdata/qemuxml2xmlout-net-virtio-rxqueuesize.xml new file mode 100644 index 0000000000..5b41936063 --- /dev/null +++ b/tests/qemuxml2xmloutdata/qemuxml2xmlout-net-virtio-rxqueuesize.xml @@ -0,0 +1,41 @@ + + QEMUGuest1 + c7a5fdbd-edaf-9455-926a-d65c16db1809 + 219100 + 219100 + 1 + + hvm + + + + destroy + restart + destroy + + /usr/bin/qemu + + + +

+ + +
+ + + +
+ + + + + +
+ + + + +
+ + + diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c index 8cdd2d7152..14c2b0ccf2 100644 --- a/tests/qemuxml2xmltest.c +++ b/tests/qemuxml2xmltest.c @@ -514,6 +514,7 @@ mymain(void) DO_TEST("net-eth-ifname", NONE); DO_TEST("net-eth-hostip", NONE); DO_TEST("net-virtio-network-portgroup", NONE); + DO_TEST("net-virtio-rxqueuesize", NONE); DO_TEST("net-hostdev", NONE); DO_TEST("net-hostdev-vfio", NONE); DO_TEST("net-midonet", NONE);