10:14 a.m.
Introduce a new <iothreads> sub-element of disk's <driver> which will
allow configuring multiple iothreads and also map them to specific
virt-queues of virtio devices.
Signed-off-by: Peter Krempa <pkrempa(a)redhat.com>
---
docs/formatdomain.rst | 23 +++++++++-
src/conf/domain_conf.c | 76 +++++++++++++++++++++++++++++++
src/conf/domain_conf.h | 14 ++++++
src/conf/domain_validate.c | 8 ++++
src/conf/schemas/domaincommon.rng | 47 ++++++++++++++-----
5 files changed, 155 insertions(+), 13 deletions(-)
diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index 96e03a3807..b8a12c2ab3 100644
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -3338,7 +3338,28 @@ paravirtualized driver is specified via the ``disk`` element.
assigned to the same IOThread and are numbered from 1 to the domain
iothreads value. Available for a disk device ``target`` configured to use
"virtio" ``bus`` and "pci" or "ccw" ``address``
types. :since:`Since 1.2.8
- (QEMU 2.1)`
+ (QEMU 2.1)` *Note:* ``iothread`` is mutually exclusive with ``iothreads``.
+ - The optional ``iothreads`` sub-element allows specifying multiple IOThreads
+ via the ``iothread`` sub-element with attribute ``id`` the disk will use
+ for I/O operations. Optionally the ``iothread`` element can have multiple
+ ``queue`` subelements specifying that given iothread should be used to
+ handle given queues. :since:`Since 10.0.0 (QEMU 9.0, virtio disks only)`.
+ Example::
+
+ <driver name='qemu' queues='2'>
+ <iothreads>
+ <iothread id='1'>
+ <queue id='1'/>
+ </iothread>
+ <iothread id='2'>
+ <queue id='1'/>
+ </iothread>
+ <iothread id='3'>
+ <queue id='2'/>
+ </iothread>
+ </iothreads>
+ </driver>
+
- The optional ``queues`` attribute specifies the number of virt queues for
virtio-blk ( :since:`Since 3.9.0` ) or vhost-user-blk
( :since `Since 7.1.0` )
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index db3d12cb49..aab37b4304 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -2337,6 +2337,17 @@ virDomainDefGetVcpusTopology(const virDomainDef *def,
}
+void
+virDomainDiskIothreadDefFree(virDomainDiskIothreadDef *def)
+{
+ if (!def)
+ return;
+
+ g_free(def->queues);
+ g_free(def);
+}
+
+
static virDomainDiskDef *
virDomainDiskDefNewSource(virDomainXMLOption *xmlopt,
virStorageSource **src)
@@ -2385,6 +2396,7 @@ virDomainDiskDefFree(virDomainDiskDef *def)
g_free(def->virtio);
virDomainDeviceInfoClear(&def->info);
virObjectUnref(def->privateData);
+ g_slist_free_full(def->iothreads, (GDestroyNotify) virDomainDiskIothreadDefFree);
g_free(def);
}
@@ -7775,6 +7787,8 @@ static int
virDomainDiskDefDriverParseXML(virDomainDiskDef *def,
xmlNodePtr cur)
{
+ xmlNodePtr iothreadsNode;
+
def->driverName = virXMLPropString(cur, "name");
if (virXMLPropEnum(cur, "cache", virDomainDiskCacheTypeFromString,
@@ -7821,6 +7835,44 @@ virDomainDiskDefDriverParseXML(virDomainDiskDef *def,
if (virXMLPropUInt(cur, "iothread", 10, VIR_XML_PROP_NONZERO,
&def->iothread) < 0)
return -1;
+ if ((iothreadsNode = virXMLNodeGetSubelement(cur, "iothreads"))) {
+ g_autoslist(virDomainDiskIothreadDef) ioth = NULL;
+ g_autoptr(GPtrArray) iothreadNodes = NULL;
+
+ if ((iothreadNodes = virXMLNodeGetSubelementList(iothreadsNode,
"iothread"))) {
+ size_t i;
+
+ for (i = 0; i < iothreadNodes->len; i++) {
+ xmlNodePtr iothNode = g_ptr_array_index(iothreadNodes, i);
+ g_autoptr(virDomainDiskIothreadDef) iothdef =
g_new0(virDomainDiskIothreadDef, 1);
+ g_autoptr(GPtrArray) queueNodes = NULL;
+
+ if (virXMLPropUInt(iothNode, "id", 10, VIR_XML_PROP_REQUIRED,
+ &iothdef->id) < 0)
+ return -1;
+
+ if ((queueNodes = virXMLNodeGetSubelementList(iothNode,
"queue"))) {
+ size_t q;
+
+ iothdef->queues = g_new0(unsigned int, queueNodes->len);
+ iothdef->nqueues = queueNodes->len;
+
+ for (q = 0; q < queueNodes->len; q++) {
+ xmlNodePtr queueNode = g_ptr_array_index(queueNodes, q);
+
+ if (virXMLPropUInt(queueNode, "id", 10,
VIR_XML_PROP_REQUIRED,
+ &(iothdef->queues[q])) < 0)
+ return -1;
+ }
+ }
+
+ ioth = g_slist_prepend(ioth, g_steal_pointer(&iothdef));
+ }
+
+ def->iothreads = g_slist_reverse(g_steal_pointer(&ioth));
+ }
+ }
+
if (virXMLPropEnum(cur, "detect_zeroes",
virDomainDiskDetectZeroesTypeFromString,
VIR_XML_PROP_NONZERO, &def->detect_zeroes) < 0)
@@ -22715,6 +22767,30 @@ virDomainDiskDefFormatDriver(virBuffer *buf,
virXMLFormatElement(&childBuf, "metadata_cache", NULL,
&metadataCacheChildBuf);
}
+ if (disk->iothreads) {
+ g_auto(virBuffer) iothreadsChildBuf = VIR_BUFFER_INIT_CHILD(&childBuf);
+ GSList *n;
+
+ for (n = disk->iothreads; n; n = n->next) {
+ virDomainDiskIothreadDef *iothDef = n->data;
+ g_auto(virBuffer) iothreadAttrBuf = VIR_BUFFER_INITIALIZER;
+ g_auto(virBuffer) iothreadChildBuf =
VIR_BUFFER_INIT_CHILD(&iothreadsChildBuf);
+
+ virBufferAsprintf(&iothreadAttrBuf, " id='%u'",
iothDef->id);
+
+ if (iothDef->queues) {
+ size_t q;
+
+ for (q = 0; q < iothDef->nqueues; q++)
+ virBufferAsprintf(&iothreadChildBuf, "<queue
id='%u'/>\n", iothDef->queues[q]);
+ }
+
+ virXMLFormatElement(&iothreadsChildBuf, "iothread",
&iothreadAttrBuf, &iothreadChildBuf);
+ }
+
+ virXMLFormatElement(&childBuf, "iothreads", NULL,
&iothreadsChildBuf);
+ }
+
virXMLFormatElement(buf, "driver", &attrBuf, &childBuf);
}
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 14901b37ba..a5757ae808 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -515,6 +515,19 @@ typedef enum {
VIR_ENUM_DECL(virDomainSnapshotLocation);
+struct _virDomainDiskIothreadDef {
+ unsigned int id;
+
+ /* optional list of virtqueues the iothread should handle */
+ unsigned int *queues;
+ size_t nqueues;
+};
+
+typedef struct _virDomainDiskIothreadDef virDomainDiskIothreadDef;
+void virDomainDiskIothreadDefFree(virDomainDiskIothreadDef *def);
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(virDomainDiskIothreadDef, virDomainDiskIothreadDefFree);
+
+
/* Stores the virtual disk configuration */
struct _virDomainDiskDef {
virStorageSource *src; /* non-NULL. XXX Allow NULL for empty cdrom? */
@@ -569,6 +582,7 @@ struct _virDomainDiskDef {
virDomainDeviceSGIO sgio;
virDomainDiskDiscard discard;
unsigned int iothread; /* unused = 0, > 0 specific thread # */
+ GSList *iothreads; /* List of virDomainDiskIothreadsDef */
virDomainDiskDetectZeroes detect_zeroes;
virTristateSwitch discard_no_unref;
char *domain_name; /* backend domain name */
diff --git a/src/conf/domain_validate.c b/src/conf/domain_validate.c
index c72108886e..d485ec4fb1 100644
--- a/src/conf/domain_validate.c
+++ b/src/conf/domain_validate.c
@@ -934,6 +934,14 @@ virDomainDiskDefValidate(const virDomainDef *def,
}
}
+ /* configuring both <driver iothread='n'> and it's
<iothreads> sub-element
+ * isn't supported */
+ if (disk->iothread && disk->iothreads) {
+ virReportError(VIR_ERR_XML_ERROR, "%s",
+ _("disk driver 'iothread' attribute can't be used
together with 'iothreads' subelement"));
+ return -1;
+ }
+
return 0;
}
diff --git a/src/conf/schemas/domaincommon.rng b/src/conf/schemas/domaincommon.rng
index f318c06797..3f856452cf 100644
--- a/src/conf/schemas/domaincommon.rng
+++ b/src/conf/schemas/domaincommon.rng
@@ -2536,9 +2536,26 @@
</optional>
</element>
</define>
- <!--
- Disk may use a special driver for access.
- -->
+
+ <define name="diskDriverIothreads">
+ <element name="iothreads">
+ <oneOrMore>
+ <element name="iothread">
+ <attribute name="id">
+ <ref name="unsignedInt"/>
+ </attribute>
+ <zeroOrMore>
+ <element name="queue">
+ <attribute name="id">
+ <ref name="unsignedInt"/>
+ </attribute>
+ </element>
+ </zeroOrMore>
+ </element>
+ </oneOrMore>
+ </element>
+ </define>
+
<define name="diskDriver">
<element name="driver">
<optional>
@@ -2590,17 +2607,23 @@
</attribute>
</optional>
<ref name="virtioOptions"/>
- <optional>
- <element name="metadata_cache">
- <optional>
- <element name="max_size">
- <ref name="scaledInteger"/>
- </element>
- </optional>
- </element>
- </optional>
+ <interleave>
+ <optional>
+ <element name="metadata_cache">
+ <optional>
+ <element name="max_size">
+ <ref name="scaledInteger"/>
+ </element>
+ </optional>
+ </element>
+ </optional>
+ <optional>
+ <ref name="diskDriverIothreads"/>
+ </optional>
+ </interleave>
</element>
</define>
+
<define name="driverFormat">
<optional>
<attribute name="name">
--
2.43.0