From 648edb64751ea0e550f36302fa66f9f11e480824 Mon Sep 17 00:00:00 2001 From: Greg Kurz Date: Wed, 14 Feb 2018 20:40:35 +0100 Subject: spapr: move VCPU calculation to core machine code 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 Signed-off-by: David Gibson --- include/hw/ppc/spapr.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h index 62c077a..af19320 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, -- cgit v1.1