9 a.m.
This patch adds support for agent-based cpu disabling and enabling to
qemuDomainSetVcpusFlags() API.
---
Notes:
Version 2:
- produce error message if setting of vcpus fails midways
src/qemu/qemu_driver.c | 129 ++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 116 insertions(+), 13 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index d0508e9..f045afd 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -3678,6 +3678,68 @@ unsupported:
static int
+qemuDomainPrepareAgentVCPUs(unsigned int nvcpus,
+ qemuAgentCPUInfoPtr cpuinfo,
+ int ncpuinfo)
+{
+ int i;
+ int nonline = 0;
+ int nofflinable = 0;
+
+ /* count the active and offlinable cpus */
+ for (i = 0; i < ncpuinfo; i++) {
+ if (cpuinfo[i].online)
+ nonline++;
+
+ if (cpuinfo[i].offlinable && cpuinfo[i].online)
+ nofflinable++;
+
+ /* This shouldn't happen, but we can't trust the guest agent */
+ if (!cpuinfo[i].online && !cpuinfo[i].offlinable) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Invalid data provided by guest agent"));
+ return -1;
+ }
+ }
+
+ /* the guest agent reported less cpus than requested */
+ if (nvcpus > ncpuinfo) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("guest agent reports less cpu than requested"));
+ return -1;
+ }
+
+ /* not enough offlinable CPUs to support the request */
+ if (nvcpus < nonline - nofflinable) {
+ virReportError(VIR_ERR_INVALID_ARG, "%s",
+ _("Cannot offline enough CPUs"));
+ return -1;
+ }
+
+ for (i = 0; i < ncpuinfo; i++) {
+ if (nvcpus < nonline) {
+ /* unplug */
+ if (cpuinfo[i].offlinable && cpuinfo[i].online) {
+ cpuinfo[i].online = false;
+ nonline--;
+ }
+ } else if (nvcpus > nonline) {
+ /* plug */
+ if (!cpuinfo[i].online) {
+ cpuinfo[i].online = true;
+ nonline++;
+ }
+ } else {
+ /* done */
+ break;
+ }
+ }
+
+ return 0;
+}
+
+
+static int
qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
unsigned int flags)
{
@@ -3688,10 +3750,14 @@ qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
bool maximum;
virQEMUDriverConfigPtr cfg = NULL;
virCapsPtr caps = NULL;
+ qemuAgentCPUInfoPtr cpuinfo = NULL;
+ int ncpuinfo;
+ qemuDomainObjPrivatePtr priv;
virCheckFlags(VIR_DOMAIN_AFFECT_LIVE |
VIR_DOMAIN_AFFECT_CONFIG |
- VIR_DOMAIN_VCPU_MAXIMUM, -1);
+ VIR_DOMAIN_VCPU_MAXIMUM |
+ VIR_DOMAIN_VCPU_AGENT, -1);
if (!nvcpus || (unsigned short) nvcpus != nvcpus) {
virReportError(VIR_ERR_INVALID_ARG,
@@ -3706,6 +3772,8 @@ qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
if (!(vm = qemuDomObjFromDomain(dom)))
goto cleanup;
+ priv = vm->privateData;
+
if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0)
goto cleanup;
@@ -3731,22 +3799,56 @@ qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
goto endjob;
}
- if (flags & VIR_DOMAIN_AFFECT_LIVE) {
- if (qemuDomainHotplugVcpus(driver, vm, nvcpus) < 0)
+ if (flags & VIR_DOMAIN_VCPU_AGENT) {
+ if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
+ virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
+ _("chainging of maximum vCPU count isn't supported
"
+ "via guest agent"));
goto endjob;
- }
-
- if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
- if (maximum) {
- persistentDef->maxvcpus = nvcpus;
- if (nvcpus < persistentDef->vcpus)
- persistentDef->vcpus = nvcpus;
- } else {
- persistentDef->vcpus = nvcpus;
}
- if (virDomainSaveConfig(cfg->configDir, persistentDef) < 0)
+ qemuDomainObjEnterAgent(vm);
+ ncpuinfo = qemuAgentGetVCPUs(priv->agent, &cpuinfo);
+ qemuDomainObjExitAgent(vm);
+
+ if (ncpuinfo < 0)
+ goto endjob;
+
+ if (qemuDomainPrepareAgentVCPUs(nvcpus, cpuinfo, ncpuinfo) < 0)
+ goto endjob;
+
+ qemuDomainObjEnterAgent(vm);
+ ret = qemuAgentSetVCPUs(priv->agent, cpuinfo, ncpuinfo);
+ qemuDomainObjExitAgent(vm);
+
+ if (ret < 0)
+ goto endjob;
+
+ if (ret < ncpuinfo) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("failed to set state of cpu %d via guest agent"),
+ cpuinfo[ret-1].id);
+ ret = -1;
goto endjob;
+ }
+ } else {
+ if (flags & VIR_DOMAIN_AFFECT_LIVE) {
+ if (qemuDomainHotplugVcpus(driver, vm, nvcpus) < 0)
+ goto endjob;
+ }
+
+ if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
+ if (maximum) {
+ persistentDef->maxvcpus = nvcpus;
+ if (nvcpus < persistentDef->vcpus)
+ persistentDef->vcpus = nvcpus;
+ } else {
+ persistentDef->vcpus = nvcpus;
+ }
+
+ if (virDomainSaveConfig(cfg->configDir, persistentDef) < 0)
+ goto endjob;
+ }
}
ret = 0;
@@ -3759,6 +3861,7 @@ cleanup:
if (vm)
virObjectUnlock(vm);
virObjectUnref(caps);
+ VIR_FREE(cpuinfo);
virObjectUnref(cfg);
return ret;
}
--
1.8.1.5