diff options
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/ppc/spapr.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 067f571..caffa12 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -26,6 +26,7 @@ */ #include "qemu/osdep.h" #include "qapi/error.h" +#include "qapi/visitor.h" #include "sysemu/sysemu.h" #include "sysemu/numa.h" #include "hw/hw.h" @@ -2165,6 +2166,61 @@ static void spapr_init_cpus(sPAPRMachineState *spapr) g_free(type); } +static void spapr_set_vsmt_mode(sPAPRMachineState *spapr, Error **errp) +{ + Error *local_err = NULL; + bool vsmt_user = !!spapr->vsmt; + int kvm_smt = kvmppc_smt_threads(); + int ret; + + if (!kvm_enabled() && (smp_threads > 1)) { + error_setg(&local_err, "TCG cannot support more than 1 thread/core " + "on a pseries machine"); + goto out; + } + if (!is_power_of_2(smp_threads)) { + error_setg(&local_err, "Cannot support %d threads/core on a pseries " + "machine because it must be a power of 2", smp_threads); + goto out; + } + + /* Detemine the VSMT mode to use: */ + if (vsmt_user) { + if (spapr->vsmt < smp_threads) { + error_setg(&local_err, "Cannot support VSMT mode %d" + " because it must be >= threads/core (%d)", + spapr->vsmt, smp_threads); + goto out; + } + /* In this case, spapr->vsmt has been set by the command line */ + } else { + /* Choose a VSMT mode that may be higher than necessary but is + * likely to be compatible with hosts that don't have VSMT. */ + spapr->vsmt = MAX(kvm_smt, smp_threads); + } + + /* KVM: If necessary, set the SMT mode: */ + if (kvm_enabled() && (spapr->vsmt != kvm_smt)) { + ret = kvmppc_set_smt_threads(spapr->vsmt); + if (ret) { + error_setg(&local_err, + "Failed to set KVM's VSMT mode to %d (errno %d)", + spapr->vsmt, ret); + if (!vsmt_user) { + error_append_hint(&local_err, "On PPC, a VM with %d threads/" + "core on a host with %d threads/core requires " + " the use of VSMT mode %d.\n", + smp_threads, kvm_smt, spapr->vsmt); + } + kvmppc_hint_smt_possible(&local_err); + goto out; + } + } + /* else TCG: nothing to do currently */ +out: + error_propagate(errp, local_err); +} + /* pSeries LPAR / sPAPR hardware init */ static void ppc_spapr_init(MachineState *machine) { @@ -2297,6 +2353,8 @@ static void ppc_spapr_init(MachineState *machine) spapr_cpu_parse_features(spapr); + spapr_set_vsmt_mode(spapr, &error_fatal); + spapr_init_cpus(spapr); if (kvm_enabled()) { @@ -2681,6 +2739,18 @@ static void spapr_set_resize_hpt(Object *obj, const char *value, Error **errp) } } +static void spapr_get_vsmt(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + visit_type_uint32(v, name, (uint32_t *)opaque, errp); +} + +static void spapr_set_vsmt(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + visit_type_uint32(v, name, (uint32_t *)opaque, errp); +} + static void spapr_machine_initfn(Object *obj) { sPAPRMachineState *spapr = SPAPR_MACHINE(obj); @@ -2711,6 +2781,11 @@ static void spapr_machine_initfn(Object *obj) object_property_set_description(obj, "resize-hpt", "Resizing of the Hash Page Table (enabled, disabled, required)", NULL); + object_property_add(obj, "vsmt", "uint32", spapr_get_vsmt, + spapr_set_vsmt, NULL, &spapr->vsmt, &error_abort); + object_property_set_description(obj, "vsmt", + "Virtual SMT: KVM behaves as if this were" + " the host's SMT mode", &error_abort); } static void spapr_machine_finalizefn(Object *obj) |