Re: [libvirt] [PATCH v2 07/21] qemu: Reuse qemuDomainDetectVcpuPids in cpu hot(un)plug

Now that qemuDomainDetectVcpuPids is able to refresh the vCPU pid information it can be reused in the hotplug and hotunplug code paths rather than open-coding a very similar algorithm. A slight algoirithm change is necessary for unplug since the vCPU needs

to be marked offline prior to calling the thread detector function and eventually rolled back if something fails. --- Notes: v2: fix bugs regarding error codes from redetection src/qemu/qemu_driver.c | 86 +++++++++++++++++--------------------------------- 1 file changed, 29 insertions(+), 57 deletions(-)

@@ -4887,49 +4865,43 @@ qemuDomainHotplugDelVcpu(virQEMUDriverPtr driver, return -1; } + vcpuinfo->online = false; + qemuDomainObjEnterMonitor(driver, vm); rc = qemuMonitorSetCPU(priv->mon, vcpu, false); - if (rc == 0) - ncpupids = qemuMonitorGetCPUInfo(priv->mon, &cpupids); - if (qemuDomainObjExitMonitor(driver, vm) < 0) goto cleanup; - virDomainAuditVcpu(vm, oldvcpus, oldvcpus - 1, "update", - rc == 0 && ncpupids == oldvcpus -1); + if (rc < 0) + rc = qemuDomainDetectVcpuPids(driver, vm, QEMU_ASYNC_JOB_NONE);

- if (rc < 0 || ncpupids < 0) - goto cleanup; + virDomainAuditVcpu(vm, oldvcpus, oldvcpus - 1, "update", rc >= 0); +

+ /* Free vcpupin setting */ + virDomainPinDel(&vm->def->cputune.vcpupin, + &vm->def->cputune.nvcpupin, + vcpu);

+ + if (rc <= 0) { + if (rc == 0) + ret = 0; - /* check if hotunplug has failed */ - if (ncpupids != oldvcpus - 1) { - virReportError(VIR_ERR_OPERATION_UNSUPPORTED, - _("qemu didn't unplug vCPU '%u' properly"), vcpu); goto cleanup; } - vcpuinfo->online = false; - if (qemuDomainDelCgroupForThread(priv->cgroup, VIR_CGROUP_THREAD_VCPU, vcpu) < 0) goto cleanup; - /* Free vcpupin setting */ - virDomainPinDel(&vm->def->cputune.vcpupin, - &vm->def->cputune.nvcpupin, - vcpu); - - priv->nvcpupids = ncpupids; - VIR_FREE(priv->vcpupids); - priv->vcpupids = cpupids; - cpupids = NULL; - ret = 0; cleanup: - VIR_FREE(cpupids); + /* rollback the cpu state */ + if (ret < 0) + vcpuinfo->online = true; +