[libvirt] [PATCH v2 1/3] conf: Add support for virtio-net.rx_queue_size
Michal Privoznik
mprivozn at redhat.com
Wed Aug 31 15:10:33 UTC 2016
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 <mprivozn at redhat.com>
---
docs/formatdomain.html.in | 16 ++++++++-
docs/schemas/domaincommon.rng | 5 +++
src/conf/domain_conf.c | 16 +++++++++
src/conf/domain_conf.h | 1 +
src/qemu/qemu_domain.c | 7 ++++
...ml2argv-net-virtio-rxqueuesize-invalid-size.xml | 29 +++++++++++++++
.../qemuxml2argv-net-virtio-rxqueuesize.xml | 29 +++++++++++++++
tests/qemuxml2argvtest.c | 1 +
.../qemuxml2xmlout-net-virtio-rxqueuesize.xml | 41 ++++++++++++++++++++++
tests/qemuxml2xmltest.c | 1 +
10 files changed, 145 insertions(+), 1 deletion(-)
create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize-invalid-size.xml
create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize.xml
create mode 100644 tests/qemuxml2xmloutdata/qemuxml2xmlout-net-virtio-rxqueuesize.xml
diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index 8c15a73..be19bb9 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -4650,7 +4650,7 @@ qemu-kvm -net nic,model=? /dev/null
<source network='default'/>
<target dev='vnet1'/>
<model type='virtio'/>
- <b><driver name='vhost' txmode='iothread' ioeventfd='on' event_idx='off' queues='5'>
+ <b><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>
@@ -4766,6 +4766,20 @@ qemu-kvm -net nic,model=? /dev/null
<span class="since">virtio-net since 1.0.6 (QEMU and KVM only)</span>
<span class="since">vhost-user since 1.2.17 (QEMU and KVM only)</span>
</dd>
+ <dt><code>rx_queue_size</code></dt>
+ <dd>
+ The optional <code>rx_queue_size</code> 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 requires value to be a power of two from [256, 1024]
+ range.
+ <span class="since">Since 2.3.0 (QEMU and KVM only)</span>
+
+ <b>In general you should leave this option alone, unless you
+ are very certain you know what you are doing.</b>
+ </dd>
</dl>
<p>
Offloading options for the host and guest can be configured using
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index 9a7d03e..387121d 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -2554,6 +2554,11 @@
</attribute>
</optional>
<optional>
+ <attribute name='rx_queue_size'>
+ <ref name='positiveInteger'/>
+ </attribute>
+ </optional>
+ <optional>
<attribute name="txmode">
<choice>
<value>iothread</value>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 61f6dbb..05a1227 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -8962,6 +8962,7 @@ 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;
@@ -9134,6 +9135,7 @@ 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",
@@ -9517,6 +9519,17 @@ 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;
+ }
+ if (q > 1)
+ 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,
@@ -9697,6 +9710,7 @@ 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);
@@ -20890,6 +20904,8 @@ 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 b889125..3411a67 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 c1fb771..29ade0e 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 0000000..d308bc1
--- /dev/null
+++ b/tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize-invalid-size.xml
@@ -0,0 +1,29 @@
+<domain type='qemu'>
+ <name>QEMUGuest1</name>
+ <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+ <memory unit='KiB'>219100</memory>
+ <currentMemory unit='KiB'>219100</currentMemory>
+ <vcpu placement='static'>1</vcpu>
+ <os>
+ <type arch='i686' machine='pc'>hvm</type>
+ <boot dev='hd'/>
+ </os>
+ <clock offset='utc'/>
+ <on_poweroff>destroy</on_poweroff>
+ <on_reboot>restart</on_reboot>
+ <on_crash>destroy</on_crash>
+ <devices>
+ <emulator>/usr/bin/qemu</emulator>
+ <disk type='block' device='disk'>
+ <source dev='/dev/HostVG/QEMUGuest1'/>
+ <target dev='hda' bus='ide'/>
+ </disk>
+ <controller type='usb' index='0'/>
+ <interface type='user'>
+ <mac address='00:11:22:33:44:55'/>
+ <model type='virtio'/>
+ <driver rx_queue_size='511'/>
+ </interface>
+ <memballoon model='virtio'/>
+ </devices>
+</domain>
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize.xml b/tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize.xml
new file mode 100644
index 0000000..cfb4742
--- /dev/null
+++ b/tests/qemuxml2argvdata/qemuxml2argv-net-virtio-rxqueuesize.xml
@@ -0,0 +1,29 @@
+<domain type='qemu'>
+ <name>QEMUGuest1</name>
+ <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+ <memory unit='KiB'>219100</memory>
+ <currentMemory unit='KiB'>219100</currentMemory>
+ <vcpu placement='static'>1</vcpu>
+ <os>
+ <type arch='i686' machine='pc'>hvm</type>
+ <boot dev='hd'/>
+ </os>
+ <clock offset='utc'/>
+ <on_poweroff>destroy</on_poweroff>
+ <on_reboot>restart</on_reboot>
+ <on_crash>destroy</on_crash>
+ <devices>
+ <emulator>/usr/bin/qemu</emulator>
+ <disk type='block' device='disk'>
+ <source dev='/dev/HostVG/QEMUGuest1'/>
+ <target dev='hda' bus='ide'/>
+ </disk>
+ <controller type='usb' index='0'/>
+ <interface type='user'>
+ <mac address='00:11:22:33:44:55'/>
+ <model type='virtio'/>
+ <driver rx_queue_size='512'/>
+ </interface>
+ <memballoon model='virtio'/>
+ </devices>
+</domain>
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index 39abe72..d0be22d 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -1043,6 +1043,7 @@ 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 0000000..5b41936
--- /dev/null
+++ b/tests/qemuxml2xmloutdata/qemuxml2xmlout-net-virtio-rxqueuesize.xml
@@ -0,0 +1,41 @@
+<domain type='qemu'>
+ <name>QEMUGuest1</name>
+ <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+ <memory unit='KiB'>219100</memory>
+ <currentMemory unit='KiB'>219100</currentMemory>
+ <vcpu placement='static'>1</vcpu>
+ <os>
+ <type arch='i686' machine='pc'>hvm</type>
+ <boot dev='hd'/>
+ </os>
+ <clock offset='utc'/>
+ <on_poweroff>destroy</on_poweroff>
+ <on_reboot>restart</on_reboot>
+ <on_crash>destroy</on_crash>
+ <devices>
+ <emulator>/usr/bin/qemu</emulator>
+ <disk type='block' device='disk'>
+ <source dev='/dev/HostVG/QEMUGuest1'/>
+ <target dev='hda' bus='ide'/>
+ <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+ </disk>
+ <controller type='usb' index='0'>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
+ </controller>
+ <controller type='pci' index='0' model='pci-root'/>
+ <controller type='ide' index='0'>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
+ </controller>
+ <interface type='user'>
+ <mac address='00:11:22:33:44:55'/>
+ <model type='virtio'/>
+ <driver rx_queue_size='512'/>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
+ </interface>
+ <input type='mouse' bus='ps2'/>
+ <input type='keyboard' bus='ps2'/>
+ <memballoon model='virtio'>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
+ </memballoon>
+ </devices>
+</domain>
diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c
index 7601a5f..602b600 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);
--
2.8.4
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