The VCPU ids are currently computed and assigned to each individual CPU threads in spapr_cpu_core_realize(). But the numbering logic of VCPU ids is actually a machine-level concept, and many places in hw/ppc/spapr.c also have to compute VCPU ids out of CPU indexes.
The current formula used in spapr_cpu_core_realize() is: vcpu_id = (cc->core_id * spapr->vsmt / smp_threads) + i where: cc->core_id is a multiple of smp_threads cpu_index = cc->core_id + i 0 <= i < smp_threads So we have: cpu_index % smp_threads == i cc->core_id / smp_threads == cpu_index / smp_threads hence: vcpu_id = (cpu_index / smp_threads) * spapr->vsmt + cpu_index % smp_threads; This formula was used before VSMT at the time VCPU ids where computed at the target emulation level. It has the advantage of being useable to derive a VPCU id out of a CPU index only. It is fitted for all the places where the machine code has to compute a VCPU id. This patch introduces an accessor to set the VCPU id in a PowerPCCPU object using the above formula. It is a first step to consolidate all the VCPU id logic in a single place. Signed-off-by: Greg Kurz <gr...@kaod.org> --- hw/ppc/spapr.c | 19 +++++++++++++++++++ hw/ppc/spapr_cpu_core.c | 9 ++------- include/hw/ppc/spapr.h | 1 + 3 files changed, 22 insertions(+), 7 deletions(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index ea7429c92a97..30cc48fd5264 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -3802,6 +3802,25 @@ int spapr_vcpu_id(PowerPCCPU *cpu) } } +void spapr_set_vcpu_id(PowerPCCPU *cpu, int cpu_index, Error **errp) +{ + sPAPRMachineState *spapr = SPAPR_MACHINE(qdev_get_machine()); + int vcpu_id; + + vcpu_id = + (cpu_index / smp_threads) * spapr->vsmt + cpu_index % smp_threads; + + if (kvm_enabled() && !kvm_vcpu_id_is_valid(vcpu_id)) { + error_setg(errp, "Can't create CPU with id %d in KVM", vcpu_id); + error_append_hint(errp, "Adjust the number of cpus to %d " + "or try to raise the number of threads per core\n", + vcpu_id * smp_threads / spapr->vsmt); + return; + } + + cpu->vcpu_id = vcpu_id; +} + PowerPCCPU *spapr_find_cpu(int vcpu_id) { CPUState *cs; diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c index 590d167b04c8..94afeb399e99 100644 --- a/hw/ppc/spapr_cpu_core.c +++ b/hw/ppc/spapr_cpu_core.c @@ -172,13 +172,8 @@ static void spapr_cpu_core_realize(DeviceState *dev, Error **errp) cs = CPU(obj); cpu = sc->threads[i] = POWERPC_CPU(obj); cs->cpu_index = cc->core_id + i; - cpu->vcpu_id = (cc->core_id * spapr->vsmt / smp_threads) + i; - if (kvm_enabled() && !kvm_vcpu_id_is_valid(cpu->vcpu_id)) { - error_setg(&local_err, "Can't create CPU with id %d in KVM", - cpu->vcpu_id); - error_append_hint(&local_err, "Adjust the number of cpus to %d " - "or try to raise the number of threads per core\n", - cpu->vcpu_id * smp_threads / spapr->vsmt); + spapr_set_vcpu_id(cpu, cs->cpu_index, &local_err); + if (local_err) { goto err; } diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h index 62c077ac2037..af19320d2f8a 100644 --- a/include/hw/ppc/spapr.h +++ b/include/hw/ppc/spapr.h @@ -767,6 +767,7 @@ void spapr_do_system_reset_on_cpu(CPUState *cs, run_on_cpu_data arg); #define HTAB_SIZE(spapr) (1ULL << ((spapr)->htab_shift)) int spapr_vcpu_id(PowerPCCPU *cpu); +void spapr_set_vcpu_id(PowerPCCPU *cpu, int cpu_index, Error **errp); PowerPCCPU *spapr_find_cpu(int vcpu_id); int spapr_irq_alloc(sPAPRMachineState *spapr, int irq_hint, bool lsi,