On 29/11/2022 18.42, Pierre Morel wrote:
We will need a Topology device to transfer the topology
during migration and to implement machine reset.
The device creation is fenced by s390_has_topology().
Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
---
...
diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c
index 2e64ffab45..973bbdd36e 100644
--- a/hw/s390x/s390-virtio-ccw.c
+++ b/hw/s390x/s390-virtio-ccw.c
@@ -44,6 +44,7 @@
#include "hw/s390x/pv.h"
#include "migration/blocker.h"
#include "qapi/visitor.h"
+#include "hw/s390x/cpu-topology.h"
static Error *pv_mig_blocker;
@@ -102,6 +103,24 @@ static void s390_init_cpus(MachineState *machine)
}
}
+static DeviceState *s390_init_topology(MachineState *machine, Error **errp)
+{
+ DeviceState *dev;
+
+ dev = qdev_new(TYPE_S390_CPU_TOPOLOGY);
+
+ object_property_add_child(&machine->parent_obj,
+ TYPE_S390_CPU_TOPOLOGY, OBJECT(dev));
+ object_property_set_int(OBJECT(dev), "num-cores",
+ machine->smp.cores * machine->smp.threads, errp);
I wonder what will happen if we ever support multithreading on s390x later?
... won't this cause some oddities when migrating older machines types with
smp.threads > 1 later? Maybe we should prohibit to enable the CPU topology
instead if a user tried to use threads > 1 with an older machine type?
Thomas
+ object_property_set_int(OBJECT(dev), "num-sockets",
+ machine->smp.sockets, errp);
+
+ sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), errp);
+
+ return dev;
+}
