[Qemu-ppc] [PATCH RFC 2/4] PPC: KVM: Move kvm_cap_smt into sPAPRMachineState

[Sam Bobroff]

PPC QEMU currenlty tracks the host's SMT mode via a KVM capability
(KVM_CAP_PPC_SMT) and this value is cached in target/ppc/kvm.c.

This patch moves that tracking into the sPAPRMachineState without
functional changes (and changes the name of kvmppc_cap_smt() to
kvmppc_get_cap_smt() to make it clear that it now fetches directly).

This will facilitate further work introducing virtual SMT modes.

Signed-off-by: Sam Bobroff <address@hidden>
---
 hw/ppc/spapr.c              | 14 ++++++++------
 include/hw/ppc/spapr.h      |  1 +
 target/ppc/kvm.c            |  6 ++----
 target/ppc/kvm_ppc.h        |  7 +------
 target/ppc/translate_init.c |  2 +-
 5 files changed, 13 insertions(+), 17 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index ede5167bc0..b33dc1b5c0 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -285,7 +285,7 @@ static int spapr_fixup_cpu_dt(void *fdt, sPAPRMachineState 
*spapr)
     int ret = 0, offset, cpus_offset;
     CPUState *cs;
     char cpu_model[32];
-    int smt = kvmppc_smt_threads();
+    int smt = spapr->vsmt;
     uint32_t pft_size_prop[] = {0, cpu_to_be32(spapr->htab_shift)};
 
     CPU_FOREACH(cs) {
@@ -563,7 +563,7 @@ static void spapr_populate_cpus_dt_node(void *fdt, 
sPAPRMachineState *spapr)
     CPUState *cs;
     int cpus_offset;
     char *nodename;
-    int smt = kvmppc_smt_threads();
+    int smt = spapr->vsmt;
 
     cpus_offset = fdt_add_subnode(fdt, 0, "cpus");
     _FDT(cpus_offset);
@@ -979,7 +979,7 @@ static void *spapr_build_fdt(sPAPRMachineState *spapr,
     void *fdt;
     sPAPRPHBState *phb;
     char *buf;
-    int smt = kvmppc_smt_threads();
+    int smt = spapr->vsmt;
 
     fdt = g_malloc0(FDT_MAX_SIZE);
     _FDT((fdt_create_empty_tree(fdt, FDT_MAX_SIZE)));
@@ -1975,7 +1975,7 @@ static void spapr_init_cpus(sPAPRMachineState *spapr)
     MachineState *machine = MACHINE(spapr);
     MachineClass *mc = MACHINE_GET_CLASS(machine);
     char *type = spapr_get_cpu_core_type(machine->cpu_model);
-    int smt = kvmppc_smt_threads();
+    int smt = spapr->vsmt;
     const CPUArchIdList *possible_cpus;
     int boot_cores_nr = smp_cpus / smp_threads;
     int i;
@@ -2489,6 +2489,7 @@ static void spapr_machine_initfn(Object *obj)
 
     spapr->htab_fd = -1;
     spapr->use_hotplug_event_source = true;
+    spapr->vsmt = (kvm_enabled() ? kvmppc_get_smt_threads() : 1);
     object_property_add_str(obj, "kvm-type",
                             spapr_get_kvm_type, spapr_set_kvm_type, NULL);
     object_property_set_description(obj, "kvm-type",
@@ -2827,11 +2828,12 @@ static
 void spapr_core_unplug_request(HotplugHandler *hotplug_dev, DeviceState *dev,
                                Error **errp)
 {
+    sPAPRMachineState *spapr = SPAPR_MACHINE(OBJECT(hotplug_dev));
     int index;
     sPAPRDRConnector *drc;
     Error *local_err = NULL;
     CPUCore *cc = CPU_CORE(dev);
-    int smt = kvmppc_smt_threads();
+    int smt = spapr->vsmt;
 
     if (!spapr_find_cpu_slot(MACHINE(hotplug_dev), cc->core_id, &index)) {
         error_setg(errp, "Unable to find CPU core with core-id: %d",
@@ -2867,7 +2869,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, 
DeviceState *dev,
     Error *local_err = NULL;
     void *fdt = NULL;
     int fdt_offset = 0;
-    int smt = kvmppc_smt_threads();
+    int smt = spapr->vsmt;
     CPUArchId *core_slot;
     int index;
 
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index f973b02845..1ddbe0b81a 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -90,6 +90,7 @@ struct sPAPRMachineState {
     sPAPROptionVector *ov5_cas;     /* negotiated (via CAS) option vectors */
     bool cas_reboot;
     bool cas_legacy_guest_workaround;
+    uint32_t vsmt;                  /* Virtual SMT mode (KVM's "core stride") 
*/
 
     Notifier epow_notifier;
     QTAILQ_HEAD(, sPAPREventLogEntry) pending_events;
diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
index f2f7c531bc..74dfab95eb 100644
--- a/target/ppc/kvm.c
+++ b/target/ppc/kvm.c
@@ -72,7 +72,6 @@ static int cap_interrupt_unset = false;
 static int cap_interrupt_level = false;
 static int cap_segstate;
 static int cap_booke_sregs;
-static int cap_ppc_smt;
 static int cap_ppc_rma;
 static int cap_spapr_tce;
 static int cap_spapr_tce_64;
@@ -127,7 +126,6 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
     cap_interrupt_level = kvm_check_extension(s, KVM_CAP_PPC_IRQ_LEVEL);
     cap_segstate = kvm_check_extension(s, KVM_CAP_PPC_SEGSTATE);
     cap_booke_sregs = kvm_check_extension(s, KVM_CAP_PPC_BOOKE_SREGS);
-    cap_ppc_smt = kvm_check_extension(s, KVM_CAP_PPC_SMT);
     cap_ppc_rma = kvm_check_extension(s, KVM_CAP_PPC_RMA);
     cap_spapr_tce = kvm_check_extension(s, KVM_CAP_SPAPR_TCE);
     cap_spapr_tce_64 = kvm_check_extension(s, KVM_CAP_SPAPR_TCE_64);
@@ -2118,9 +2116,9 @@ void kvmppc_set_mpic_proxy(PowerPCCPU *cpu, int 
mpic_proxy)
     }
 }
 
-int kvmppc_smt_threads(void)
+int kvmppc_get_smt_threads(void)
 {
-    return cap_ppc_smt ? cap_ppc_smt : 1;
+    return kvm_vm_check_extension(kvm_state, KVM_CAP_PPC_SMT);
 }
 
 #ifdef TARGET_PPC64
diff --git a/target/ppc/kvm_ppc.h b/target/ppc/kvm_ppc.h
index eab7c8fdb3..cdc1407462 100644
--- a/target/ppc/kvm_ppc.h
+++ b/target/ppc/kvm_ppc.h
@@ -28,7 +28,7 @@ void kvmppc_enable_clear_ref_mod_hcalls(void);
 void kvmppc_set_papr(PowerPCCPU *cpu);
 int kvmppc_set_compat(PowerPCCPU *cpu, uint32_t compat_pvr);
 void kvmppc_set_mpic_proxy(PowerPCCPU *cpu, int mpic_proxy);
-int kvmppc_smt_threads(void);
+int kvmppc_get_smt_threads(void);
 int kvmppc_clear_tsr_bits(PowerPCCPU *cpu, uint32_t tsr_bits);
 int kvmppc_or_tsr_bits(PowerPCCPU *cpu, uint32_t tsr_bits);
 int kvmppc_set_tcr(PowerPCCPU *cpu);
@@ -138,11 +138,6 @@ static inline void kvmppc_set_mpic_proxy(PowerPCCPU *cpu, 
int mpic_proxy)
 {
 }
 
-static inline int kvmppc_smt_threads(void)
-{
-    return 1;
-}
-
 static inline int kvmppc_or_tsr_bits(PowerPCCPU *cpu, uint32_t tsr_bits)
 {
     return 0;
diff --git a/target/ppc/translate_init.c b/target/ppc/translate_init.c
index 56a0ab22cf..0d3da9d746 100644
--- a/target/ppc/translate_init.c
+++ b/target/ppc/translate_init.c
@@ -9827,7 +9827,7 @@ static void ppc_cpu_realizefn(DeviceState *dev, Error 
**errp)
     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
     Error *local_err = NULL;
 #if !defined(CONFIG_USER_ONLY)
-    int max_smt = kvmppc_smt_threads();
+    int max_smt = kvmppc_get_smt_threads();
 #endif
 
 #if !defined(CONFIG_USER_ONLY)
-- 
2.12.1.382.gc0f9c7058