[libvirt] [PATCH 2/3] qemu: Re-detect virtual cpu threads after cpu hot (un)plug.

After a cpu hotplug the qemu driver did not refresh information about virtual procesors used by qemu and their corresponding threads. This patch forces a re-detection as is done on start of QEMU. This ensures that correct informations are reported by the virDomainGetVcpus API and "virsh vcpuinfo". --- src/qemu/qemu_driver.c | 24 ++++++++++++++++++++++++ 1 files changed, 24 insertions(+), 0 deletions(-) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 7b1d1b6..fcaf0d2 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -3343,6 +3343,8 @@ static int qemudDomainHotplugVcpus(struct qemud_driver *driver, int ret = -1; int oldvcpus = vm->def->vcpus; int vcpus = oldvcpus; + pid_t *cpupids = NULL; + int ncpupids; qemuDomainObjEnterMonitor(driver, vm); @@ -3373,8 +3375,30 @@ static int qemudDomainHotplugVcpus(struct qemud_driver *driver, } } + /* after hotplugging the cpu we need to re-detect threads for the virtual + * cpus */ + if ((ncpupids = qemuMonitorGetCPUInfo(priv->mon, &cpupids)) < 0) + goto cleanup; + ret = 0; + /* Treat failure to get VCPU<->PID mapping as non-fatal */ + if (ncpupids == 0) + goto cleanup; + + if (ncpupids != vcpus) { + qemuReportError(VIR_ERR_INTERNAL_ERROR, + _("got wrong number of vCPU pids from QEMU monitor. " + "got %d, wanted %d"), + ncpupids, vcpus); + VIR_FREE(cpupids); + ret = -1; + goto cleanup; + } + + priv->nvcpupids = ncpupids; + priv->vcpupids = cpupids; + cleanup: qemuDomainObjExitMonitor(driver, vm); vm->def->vcpus = vcpus; -- 1.7.3.4