Support hot removal of CPU for sPAPR guests by sending the hot
unplug notification to the guest via EPOW interrupt.
Signed-off-by: Bharata B Rao <bhar...@linux.vnet.ibm.com>
---
hw/ppc/spapr.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++-
linux-headers/linux/kvm.h | 1 +
target-ppc/kvm.c | 7 +++++
target-ppc/kvm_ppc.h | 6 ++++
4 files changed, 91 insertions(+), 1 deletion(-)
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index b48994b..7b8784d 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1468,6 +1468,12 @@ static void spapr_cpu_init(PowerPCCPU *cpu)
qemu_register_reset(spapr_cpu_reset, cpu);
}
+static void spapr_cpu_destroy(PowerPCCPU *cpu)
+{
+ xics_cpu_destroy(spapr->icp, cpu);
+ qemu_unregister_reset(spapr_cpu_reset, cpu);
+}
+
/* pSeries LPAR / sPAPR hardware init */
static void ppc_spapr_init(MachineState *machine)
{
@@ -1880,6 +1886,18 @@ static void spapr_cpu_hotplug_add(DeviceState *dev,
CPUState *cs, Error **errp)
}
}
+static void spapr_cpu_hotplug_remove(DeviceState *dev, CPUState *cs,
+ Error **errp)
+{
+ PowerPCCPU *cpu = POWERPC_CPU(cs);
+ int id = ppc_get_vcpu_dt_id(cpu);
+ sPAPRDRConnector *drc =
+ spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_CPU, id);
+ sPAPRDRConnectorClass *drck = SPAPR_DR_CONNECTOR_GET_CLASS(drc);
+
+ drck->detach(drc, dev, NULL, NULL, errp);
+}
+
static void spapr_cpu_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
Error **errp)
{
@@ -1911,6 +1929,51 @@ static void spapr_cpu_plug(HotplugHandler *hotplug_dev,
DeviceState *dev,
return;
}
+static int spapr_cpu_unplug(Object *obj, void *opaque)
+{
+ Error **errp = opaque;
+ DeviceState *dev = DEVICE(obj);
+ CPUState *cs = CPU(dev);
+ PowerPCCPU *cpu = POWERPC_CPU(cs);
+ int id = ppc_get_vcpu_dt_id(cpu);
+ int smt = kvmppc_smt_threads();
+ sPAPRDRConnector *drc =
+ spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_CPU, id);
+
+ spapr_cpu_destroy(cpu);
+
+ /*
+ * SMT threads return from here, only main thread (core) will
+ * continue and signal hot unplug event to the guest.
+ */
+ if ((id % smt) != 0) {
+ return 0;
+ }
+ g_assert(drc);
+
+ spapr_cpu_hotplug_remove(dev, cs, errp);
+ if (*errp) {
+ return -1;
+ }
+ spapr_hotplug_req_remove_event(drc);
+
+ return 0;
+}
+
+static int spapr_cpu_core_unplug(Object *obj, void *opaque)
+{
+ Error **errp = opaque;
+
+ object_child_foreach(obj, spapr_cpu_unplug, errp);
+ return 0;
+}
+
+static void spapr_cpu_socket_unplug(HotplugHandler *hotplug_dev,
+ DeviceState *dev, Error **errp)
+{
+ object_child_foreach(OBJECT(dev), spapr_cpu_core_unplug, errp);
+}
+
static void spapr_machine_device_plug(HotplugHandler *hotplug_dev,
DeviceState *dev, Error **errp)
{
@@ -1926,10 +1989,21 @@ static void spapr_machine_device_plug(HotplugHandler
*hotplug_dev,
}
}
+static void spapr_machine_device_unplug(HotplugHandler *hotplug_dev,
+ DeviceState *dev, Error **errp)
+{
+ if (object_dynamic_cast(OBJECT(dev), TYPE_CPU_SOCKET)) {
+ if (dev->hotplugged && spapr->dr_cpu_enabled) {
+ spapr_cpu_socket_unplug(hotplug_dev, dev, errp);
+ }
+ }
+}
+
static HotplugHandler *spapr_get_hotpug_handler(MachineState *machine,
DeviceState *dev)
{
- if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
+ if (object_dynamic_cast(OBJECT(dev), TYPE_CPU) ||
+ object_dynamic_cast(OBJECT(dev), TYPE_CPU_SOCKET)) {
return HOTPLUG_HANDLER(machine);
}
return NULL;
@@ -1953,6 +2027,8 @@ static void spapr_machine_class_init(ObjectClass *oc,
void *data)
mc->has_dynamic_sysbus = true;
mc->get_hotplug_handler = spapr_get_hotpug_handler;
hc->plug = spapr_machine_device_plug;
+ hc->unplug = spapr_machine_device_unplug;
+
smc->dr_phb_enabled = false;
smc->dr_cpu_enabled = false;
smc->dr_lmb_enabled = false;
diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index 12045a1..0c1be07 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -761,6 +761,7 @@ struct kvm_ppc_smmu_info {
#define KVM_CAP_PPC_FIXUP_HCALL 103
#define KVM_CAP_PPC_ENABLE_HCALL 104
#define KVM_CAP_CHECK_EXTENSION_VM 105
+#define KVM_CAP_SPAPR_REUSE_VCPU 107
#ifdef KVM_CAP_IRQ_ROUTING
diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
index 1edf2b5..ee23bf6 100644
--- a/target-ppc/kvm.c
+++ b/target-ppc/kvm.c
@@ -72,6 +72,7 @@ static int cap_ppc_watchdog;
static int cap_papr;
static int cap_htab_fd;
static int cap_fixup_hcalls;
+static int cap_spapr_reuse_vcpu;
static uint32_t debug_inst_opcode;
@@ -114,6 +115,7 @@ int kvm_arch_init(KVMState *s)
* only activated after this by kvmppc_set_papr() */
cap_htab_fd = kvm_check_extension(s, KVM_CAP_PPC_HTAB_FD);
cap_fixup_hcalls = kvm_check_extension(s, KVM_CAP_PPC_FIXUP_HCALL);
+ cap_spapr_reuse_vcpu = kvm_check_extension(s, KVM_CAP_SPAPR_REUSE_VCPU);
if (!cap_interrupt_level) {
fprintf(stderr, "KVM: Couldn't find level irq capability. Expect the "
@@ -2408,3 +2410,8 @@ int kvm_arch_fixup_msi_route(struct kvm_irq_routing_entry
*route,
{
return 0;
}
+
+bool kvmppc_spapr_reuse_vcpu(void)
+{
+ return cap_spapr_reuse_vcpu;
+}
diff --git a/target-ppc/kvm_ppc.h b/target-ppc/kvm_ppc.h
index 2e0224c..c831229 100644
--- a/target-ppc/kvm_ppc.h
+++ b/target-ppc/kvm_ppc.h
@@ -40,6 +40,7 @@ void *kvmppc_create_spapr_tce(uint32_t liobn, uint32_t
window_size, int *pfd,
int kvmppc_remove_spapr_tce(void *table, int pfd, uint32_t window_size);
int kvmppc_reset_htab(int shift_hint);
uint64_t kvmppc_rma_size(uint64_t current_size, unsigned int hash_shift);
+bool kvmppc_spapr_reuse_vcpu(void);
#endif /* !CONFIG_USER_ONLY */
bool kvmppc_has_cap_epr(void);
int kvmppc_define_rtas_kernel_token(uint32_t token, const char *function);
@@ -185,6 +186,11 @@ static inline int kvmppc_update_sdr1(CPUPPCState *env)
return 0;
}
+static inline bool kvmppc_spapr_reuse_vcpu(void)
+{
+ return false;
+}
+
#endif /* !CONFIG_USER_ONLY */
static inline bool kvmppc_has_cap_epr(void)
--
2.1.0
