[PATCH v2 3/4] conf: Introduce TCG domain features
Michal Privoznik
mprivozn at redhat.com
Fri Nov 5 09:35:19 UTC 2021
It may come handy to be able to tweak TCG options, in this
specific case the size of translation block cache size (tb-size).
Since we can expect more knobs to tweak let's put them under
common element, like this:
<domain>
<features>
<tcg>
<tb-cache unit='MiB'>128</tb-cache>
</tcg>
</features>
</domain>
Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
Tested-by: Kashyap Chamarthy <kchamart at redhat.com>
---
docs/formatdomain.rst | 11 +++
docs/schemas/domaincommon.rng | 15 +++-
src/conf/domain_conf.c | 90 +++++++++++++++++++
src/conf/domain_conf.h | 7 ++
src/qemu/qemu_validate.c | 11 +++
.../x86_64-default-cpu-tcg-features.xml | 67 ++++++++++++++
...default-cpu-tcg-features.x86_64-latest.xml | 1 +
tests/qemuxml2xmltest.c | 1 +
8 files changed, 202 insertions(+), 1 deletion(-)
create mode 100644 tests/qemuxml2argvdata/x86_64-default-cpu-tcg-features.xml
create mode 120000 tests/qemuxml2xmloutdata/x86_64-default-cpu-tcg-features.x86_64-latest.xml
diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index eb8c973cf1..1b7e92b3ba 100644
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -1864,6 +1864,9 @@ Hypervisors may allow certain CPU / machine features to be toggled on/off.
<cfpc value='workaround'/>
<sbbc value='workaround'/>
<ibs value='fixed-na'/>
+ <tcg>
+ <tb-cache unit='MiB'>128</tb-cache>
+ </tcg>
</features>
...
@@ -2065,6 +2068,14 @@ are:
``fixed-na (fixed in hardware - no longer applicable)``. If the
attribute is not defined, the hypervisor default will be used. :since:`Since
6.3.0` (QEMU/KVM only)
+``tcg``
+ Various features to change the behavior of the TCG accelerator.
+
+ =========== ============================================== =================================================== ==============
+ Feature Description Value Since
+ =========== ============================================== =================================================== ==============
+ tb-cache The size of translation block cache size an integer :since:`7.10.0`
+ =========== ============================================== =================================================== ==============
:anchor:`<a id="elementsTime"/>`
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index f01b7a6470..ce51e95895 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -6092,7 +6092,7 @@
</element>
</define>
<!--
- A set of optional features: PAE, APIC, ACPI, GIC,
+ A set of optional features: PAE, APIC, ACPI, GIC, TCG,
HyperV Enlightenment, KVM features, paravirtual spinlocks and HAP support
-->
<define name="features">
@@ -6232,6 +6232,9 @@
<optional>
<ref name="ibs"/>
</optional>
+ <optional>
+ <ref name="tcgfeatures"/>
+ </optional>
</interleave>
</element>
</optional>
@@ -6520,6 +6523,16 @@
</element>
</define>
+ <define name="tcgfeatures">
+ <element name="tcg">
+ <optional>
+ <element name="tb-cache">
+ <ref name="scaledInteger"/>
+ </element>
+ </optional>
+ </element>
+ </define>
+
<define name="address">
<element name="address">
<choice>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index da0c64b460..496e43dc02 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -172,6 +172,7 @@ VIR_ENUM_IMPL(virDomainFeature,
"cfpc",
"sbbc",
"ibs",
+ "tcg",
);
VIR_ENUM_IMPL(virDomainCapabilitiesPolicy,
@@ -17679,6 +17680,30 @@ virDomainFeaturesCapabilitiesDefParse(virDomainDef *def,
}
+static int
+virDomainFeaturesTCGDefParse(virDomainDef *def,
+ xmlXPathContextPtr ctxt,
+ xmlNodePtr node)
+{
+ g_autofree virDomainFeatureTCG *tcg = NULL;
+ VIR_XPATH_NODE_AUTORESTORE(ctxt);
+
+ tcg = g_new0(virDomainFeatureTCG, 1);
+ ctxt->node = node;
+
+ if (virDomainParseMemory("./tb-cache", "./tb-cache/@unit",
+ ctxt, &tcg->tb_cache, false, false) < 0)
+ return -1;
+
+ if (tcg->tb_cache == 0)
+ return 0;
+
+ def->features[VIR_DOMAIN_FEATURE_TCG] = VIR_TRISTATE_SWITCH_ON;
+ def->tcg_features = g_steal_pointer(&tcg);
+ return 0;
+}
+
+
static int
virDomainFeaturesDefParse(virDomainDef *def,
xmlXPathContextPtr ctxt)
@@ -17887,6 +17912,11 @@ virDomainFeaturesDefParse(virDomainDef *def,
break;
}
+ case VIR_DOMAIN_FEATURE_TCG:
+ if (virDomainFeaturesTCGDefParse(def, ctxt, nodes[i]) < 0)
+ return -1;
+ break;
+
case VIR_DOMAIN_FEATURE_LAST:
break;
}
@@ -21555,6 +21585,39 @@ virDomainRedirFilterDefCheckABIStability(virDomainRedirFilterDef *src,
}
+static bool
+virDomainFeatureTCGCheckABIStability(const virDomainDef *src,
+ const virDomainDef *dst)
+{
+ const int srcF = src->features[VIR_DOMAIN_FEATURE_TCG];
+ const int dstF = dst->features[VIR_DOMAIN_FEATURE_TCG];
+
+ if (srcF != dstF ||
+ !!src->tcg_features != !!dst->tcg_features) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+ _("State of feature '%s' differs: "
+ "source: '%s', destination: '%s'"),
+ virDomainFeatureTypeToString(VIR_DOMAIN_FEATURE_TCG),
+ virTristateSwitchTypeToString(srcF),
+ virTristateSwitchTypeToString(dstF));
+ return false;
+ }
+
+ if (!src->tcg_features && !dst->tcg_features)
+ return true;
+
+ if (src->tcg_features->tb_cache != dst->tcg_features->tb_cache) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+ _("TCG tb-cache mismatch: source %llu, destination: %llu"),
+ src->tcg_features->tb_cache,
+ dst->tcg_features->tb_cache);
+ return false;
+ }
+
+ return true;
+}
+
+
static bool
virDomainDefFeaturesCheckABIStability(virDomainDef *src,
virDomainDef *dst)
@@ -21705,6 +21768,11 @@ virDomainDefFeaturesCheckABIStability(virDomainDef *src,
case VIR_DOMAIN_FEATURE_MSRS:
break;
+ case VIR_DOMAIN_FEATURE_TCG:
+ if (!virDomainFeatureTCGCheckABIStability(src, dst))
+ return false;
+ break;
+
case VIR_DOMAIN_FEATURE_LAST:
break;
}
@@ -27691,6 +27759,24 @@ virDomainDefFormatBlkiotune(virBuffer *buf,
}
+static void
+virDomainFeatureTCGFormat(virBuffer *buf,
+ const virDomainDef *def)
+{
+ g_auto(virBuffer) childBuf = VIR_BUFFER_INIT_CHILD(buf);
+
+ if (!def->tcg_features ||
+ def->features[VIR_DOMAIN_FEATURE_TCG] != VIR_TRISTATE_SWITCH_ON)
+ return;
+
+ virBufferAsprintf(&childBuf,
+ "<tb-cache unit='KiB'>%lld</tb-cache>\n",
+ def->tcg_features->tb_cache);
+
+ virXMLFormatElement(buf, "tcg", NULL, &childBuf);
+}
+
+
static int
virDomainDefFormatFeatures(virBuffer *buf,
virDomainDef *def)
@@ -28011,6 +28097,10 @@ virDomainDefFormatFeatures(virBuffer *buf,
virDomainIBSTypeToString(def->features[i]));
break;
+ case VIR_DOMAIN_FEATURE_TCG:
+ virDomainFeatureTCGFormat(&childBuf, def);
+ break;
+
case VIR_DOMAIN_FEATURE_LAST:
break;
}
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index ab9a7d66f8..9c66e26ccf 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -2054,6 +2054,7 @@ typedef enum {
VIR_DOMAIN_FEATURE_CFPC,
VIR_DOMAIN_FEATURE_SBBC,
VIR_DOMAIN_FEATURE_IBS,
+ VIR_DOMAIN_FEATURE_TCG,
VIR_DOMAIN_FEATURE_LAST
} virDomainFeature;
@@ -2262,6 +2263,11 @@ typedef enum {
VIR_ENUM_DECL(virDomainIBS);
+typedef struct _virDomainFeatureTCG virDomainFeatureTCG;
+struct _virDomainFeatureTCG {
+ unsigned long long tb_cache; /* Stored in KiB */
+};
+
/* Operating system configuration data & machine / arch */
struct _virDomainOSEnv {
char *name;
@@ -2824,6 +2830,7 @@ struct _virDomainDef {
unsigned long long hpt_maxpagesize; /* Stored in KiB */
char *hyperv_vendor_id;
virTristateSwitch apic_eoi;
+ virDomainFeatureTCG *tcg_features;
bool tseg_specified;
unsigned long long tseg_size;
diff --git a/src/qemu/qemu_validate.c b/src/qemu/qemu_validate.c
index 397eea5ede..bd33c9a800 100644
--- a/src/qemu/qemu_validate.c
+++ b/src/qemu/qemu_validate.c
@@ -294,6 +294,17 @@ qemuValidateDomainDefFeatures(const virDomainDef *def,
}
break;
+ case VIR_DOMAIN_FEATURE_TCG:
+ if (def->features[i] == VIR_TRISTATE_SWITCH_ON) {
+ if (def->virtType != VIR_DOMAIN_VIRT_QEMU) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+ _("TCG features are incompatible with domain type '%s'"),
+ virDomainVirtTypeToString(def->virtType));
+ return -1;
+ }
+ }
+ break;
+
case VIR_DOMAIN_FEATURE_SMM:
case VIR_DOMAIN_FEATURE_KVM:
case VIR_DOMAIN_FEATURE_XEN:
diff --git a/tests/qemuxml2argvdata/x86_64-default-cpu-tcg-features.xml b/tests/qemuxml2argvdata/x86_64-default-cpu-tcg-features.xml
new file mode 100644
index 0000000000..e2058487b2
--- /dev/null
+++ b/tests/qemuxml2argvdata/x86_64-default-cpu-tcg-features.xml
@@ -0,0 +1,67 @@
+<domain type='qemu'>
+ <name>guest</name>
+ <uuid>1ccfd97d-5eb4-478a-bbe6-88d254c16db7</uuid>
+ <memory unit='KiB'>4194304</memory>
+ <currentMemory unit='KiB'>4194304</currentMemory>
+ <vcpu placement='static'>4</vcpu>
+ <os>
+ <type arch='x86_64' machine='pc-q35-6.2'>hvm</type>
+ <boot dev='hd'/>
+ </os>
+ <features>
+ <acpi/>
+ <apic/>
+ <tcg>
+ <tb-cache unit='KiB'>102400</tb-cache>
+ </tcg>
+ </features>
+ <cpu mode='custom' match='exact' check='none'>
+ <model fallback='forbid'>qemu64</model>
+ </cpu>
+ <clock offset='utc'/>
+ <on_poweroff>destroy</on_poweroff>
+ <on_reboot>restart</on_reboot>
+ <on_crash>destroy</on_crash>
+ <devices>
+ <emulator>/usr/bin/qemu-system-x86_64</emulator>
+ <disk type='file' device='disk'>
+ <driver name='qemu' type='qcow2'/>
+ <source file='/var/lib/libvirt/images/guest.qcow2'/>
+ <target dev='vda' bus='virtio'/>
+ <address type='pci' domain='0x0000' bus='0x02' slot='0x00' function='0x0'/>
+ </disk>
+ <controller type='usb' index='0' model='qemu-xhci'>
+ <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
+ </controller>
+ <controller type='sata' index='0'>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
+ </controller>
+ <controller type='pci' index='0' model='pcie-root'/>
+ <controller type='pci' index='1' model='pcie-root-port'>
+ <model name='pcie-root-port'/>
+ <target chassis='1' port='0x8'/>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0' multifunction='on'/>
+ </controller>
+ <controller type='pci' index='2' model='pcie-root-port'>
+ <model name='pcie-root-port'/>
+ <target chassis='2' port='0x9'/>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
+ </controller>
+ <controller type='pci' index='3' model='pcie-root-port'>
+ <model name='pcie-root-port'/>
+ <target chassis='3' port='0xa'/>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
+ </controller>
+ <controller type='pci' index='4' model='pcie-root-port'>
+ <model name='pcie-root-port'/>
+ <target chassis='4' port='0xb'/>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x3'/>
+ </controller>
+ <input type='mouse' bus='ps2'/>
+ <input type='keyboard' bus='ps2'/>
+ <audio id='1' type='none'/>
+ <memballoon model='virtio'>
+ <address type='pci' domain='0x0000' bus='0x03' slot='0x00' function='0x0'/>
+ </memballoon>
+ </devices>
+</domain>
diff --git a/tests/qemuxml2xmloutdata/x86_64-default-cpu-tcg-features.x86_64-latest.xml b/tests/qemuxml2xmloutdata/x86_64-default-cpu-tcg-features.x86_64-latest.xml
new file mode 120000
index 0000000000..8226a54027
--- /dev/null
+++ b/tests/qemuxml2xmloutdata/x86_64-default-cpu-tcg-features.x86_64-latest.xml
@@ -0,0 +1 @@
+../qemuxml2argvdata/x86_64-default-cpu-tcg-features.xml
\ No newline at end of file
diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c
index 7ea066fcda..500386fd00 100644
--- a/tests/qemuxml2xmltest.c
+++ b/tests/qemuxml2xmltest.c
@@ -1386,6 +1386,7 @@ mymain(void)
DO_TEST_CAPS_ARCH_LATEST("x86_64-default-cpu-tcg-pc-4.2", "x86_64");
DO_TEST_CAPS_ARCH_LATEST("x86_64-default-cpu-kvm-q35-4.2", "x86_64");
DO_TEST_CAPS_ARCH_LATEST("x86_64-default-cpu-tcg-q35-4.2", "x86_64");
+ DO_TEST_CAPS_ARCH_LATEST("x86_64-default-cpu-tcg-features", "x86_64");
DO_TEST_CAPS_LATEST("virtio-9p-multidevs");
DO_TEST_CAPS_LATEST("virtio-9p-createmode");
--
2.32.0
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