target/ppc: Clarify compat mode max_threads value

We recently had some discussions that were sidetracked for a while, because
nearly everyone misapprehended the purpose of the 'max_threads' field in
the compatiblity modes table.  It's all about guest expectations, not host
expectations or support (that's handled elsewhere).

In an attempt to avoid a repeat of that confusion, rename the field to
'max_vthreads' and add an explanatory comment.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Jose Ricardo Ziviani <joserz@linux.vnet.ibm.com>
This commit is contained in:
David Gibson 2018-01-15 16:40:23 +11:00
parent 03ee51d354
commit abbc124753
3 changed files with 20 additions and 11 deletions

View file

@ -345,7 +345,7 @@ static int spapr_fixup_cpu_dt(void *fdt, sPAPRMachineState *spapr)
PowerPCCPU *cpu = POWERPC_CPU(cs);
DeviceClass *dc = DEVICE_GET_CLASS(cs);
int index = spapr_vcpu_id(cpu);
int compat_smt = MIN(smp_threads, ppc_compat_max_threads(cpu));
int compat_smt = MIN(smp_threads, ppc_compat_max_vthreads(cpu));
if ((index % smt) != 0) {
continue;
@ -503,7 +503,7 @@ static void spapr_populate_cpu_dt(CPUState *cs, void *fdt, int offset,
size_t page_sizes_prop_size;
uint32_t vcpus_per_socket = smp_threads * smp_cores;
uint32_t pft_size_prop[] = {0, cpu_to_be32(spapr->htab_shift)};
int compat_smt = MIN(smp_threads, ppc_compat_max_threads(cpu));
int compat_smt = MIN(smp_threads, ppc_compat_max_vthreads(cpu));
sPAPRDRConnector *drc;
int drc_index;
uint32_t radix_AP_encodings[PPC_PAGE_SIZES_MAX_SZ];