spapr: Unrealize vCPUs with qdev_unrealize()

Since we introduced CPU hot-unplug in sPAPR, we don't unrealize the
vCPU objects explicitly. Instead, we let QOM handle that for us under
object_property_del_all() when the CPU core object is finalized. The
only thing we do is calling cpu_remove_sync() to tear the vCPU thread
down.

This happens to work but it is ugly because:
- we call qdev_realize() but the corresponding qdev_unrealize() is
  buried deep in the QOM code
- we call cpu_remove_sync() to undo qemu_init_vcpu() called by
  ppc_cpu_realize() in target/ppc/translate_init.c.inc
- the CPU init and teardown paths aren't really symmetrical

The latter didn't bite us so far but a future patch that greatly
simplifies the CPU core realize path needs it to avoid a crash
in QOM.

For all these reasons, have ppc_cpu_unrealize() to undo the changes
of ppc_cpu_realize() by calling cpu_remove_sync() at the right place,
and have the sPAPR CPU core code to call qdev_unrealize().

This requires to add a missing stub because translate_init.c.inc is
also compiled for user mode.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <160279671236.1808373.14732005038172874990.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Greg Kurz 2020-10-15 23:18:32 +02:00 committed by David Gibson
parent 90689a32ce
commit f1023d21e8
3 changed files with 8 additions and 2 deletions

View file

@ -9,6 +9,10 @@ void cpu_resume(CPUState *cpu)
{
}
void cpu_remove_sync(CPUState *cpu)
{
}
void qemu_init_vcpu(CPUState *cpu)
{
}

View file

@ -187,7 +187,7 @@ static void spapr_unrealize_vcpu(PowerPCCPU *cpu, SpaprCpuCore *sc)
vmstate_unregister(NULL, &vmstate_spapr_cpu_state, cpu->machine_data);
}
spapr_irq_cpu_intc_destroy(SPAPR_MACHINE(qdev_get_machine()), cpu);
cpu_remove_sync(CPU(cpu));
qdev_unrealize(DEVICE(cpu));
}
/*
@ -255,7 +255,7 @@ static bool spapr_realize_vcpu(PowerPCCPU *cpu, SpaprMachineState *spapr,
kvmppc_set_papr(cpu);
if (spapr_irq_cpu_intc_create(spapr, cpu, errp) < 0) {
cpu_remove_sync(CPU(cpu));
qdev_unrealize(DEVICE(cpu));
return false;
}

View file

@ -10328,6 +10328,8 @@ static void ppc_cpu_unrealize(DeviceState *dev)
pcc->parent_unrealize(dev);
cpu_remove_sync(CPU(cpu));
for (i = 0; i < PPC_CPU_OPCODES_LEN; i++) {
if (cpu->opcodes[i] == &invalid_handler) {
continue;