spapr: Set VSMT to smp_threads by default

Support for setting VSMT is available in KVM since linux-4.13. Most distros
that support KVM on POWER already have it. It thus seem reasonable enough
to have the default machine to set VSMT to smp_threads.

This brings contiguous VCPU ids and thus brings their upper bound down to
the machine's max_cpus. This is especially useful for XIVE KVM devices,
which may thus allocate only one VP descriptor per VCPU.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <157010411885.246126.12610015369068227139.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Greg Kurz 2019-10-03 14:02:00 +02:00 committed by David Gibson
parent 06d26eeb47
commit 29cb418749
2 changed files with 7 additions and 1 deletions

View file

@ -122,6 +122,7 @@ struct SpaprMachineClass {
bool broken_host_serial_model; /* present real host info to the guest */
bool pre_4_1_migration; /* don't migrate hpt-max-page-size */
bool linux_pci_probe;
bool smp_threads_vsmt; /* set VSMT to smp_threads by default */
void (*phb_placement)(SpaprMachineState *spapr, uint32_t index,
uint64_t *buid, hwaddr *pio,