On 2018/3/27 22:15, Eric Auger wrote:
> With KVM acceleration and if KVM VGICV3 supports to set multiple
> redistributor regions, we now allow up to 512 vcpus.
>
> Signed-off-by: Eric Auger <eric.au...@redhat.com>
> ---
> hw/arm/virt.c | 17 ++++++++++++++++-
> include/hw/arm/virt.h | 1 +
> 2 files changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 8258f6f..cdb1a75 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -149,8 +149,10 @@ static const MemMapEntry a15memmap[] = {
> [VIRT_PCIE_PIO] = { 0x3eff0000, 0x00010000 },
> [VIRT_PCIE_ECAM] = { 0x3f000000, 0x01000000 },
> [VIRT_MEM] = { 0x40000000, RAMLIMIT_BYTES },
> + /* Allows 512 - 123 additional vcpus (each 2x64kB) */
> + [VIRT_GIC_REDIST2] = { 0x4000000000ULL, 0x30A0000LL },
One concern that this will limit the guest ram size to RAMLIMIT_BYTES.
If we want to support larger ram size in the future, this may be a problem.
> /* Second PCIe window, 512GB wide at the 512GB boundary */
> - [VIRT_PCIE_MMIO_HIGH] = { 0x8000000000ULL, 0x8000000000ULL },
> + [VIRT_PCIE_MMIO_HIGH] = { 0x8000000000ULL, 0x8000000000ULL },
> };
>
> static const int a15irqmap[] = {
> @@ -553,6 +555,11 @@ static void create_gic(VirtMachineState *vms, qemu_irq
> *pic)
> agcc->register_redist_region((GICv3State *)gicdev,
> vms->memmap[VIRT_GIC_REDIST].base,
> vms->memmap[VIRT_GIC_REDIST].size >> 17);
> + if (vms->smp_cpus > 123) {
> + agcc->register_redist_region((GICv3State *)gicdev,
> + vms->memmap[VIRT_GIC_REDIST2].base,
> + vms->memmap[VIRT_GIC_REDIST2].size >> 17);
> + }
> } else {
> sysbus_mmio_map(gicbusdev, 1, vms->memmap[VIRT_GIC_CPU].base);
> }
> @@ -1284,6 +1291,14 @@ static void machvirt_init(MachineState *machine)
> */
> if (vms->gic_version == 3) {
> virt_max_cpus = vms->memmap[VIRT_GIC_REDIST].size / 0x20000;
> + if (kvm_max_vcpus(kvm_state) > 255) {
> + /*
> + * VGICv3 KVM device capability to set multiple redistributor
> + * was introduced at the same time KVM_MAX_VCPUS was bumped
> + * from 255 to 512
> + */
> + virt_max_cpus += vms->memmap[VIRT_GIC_REDIST2].size / 0x20000;
> + }
> } else {
> virt_max_cpus = GIC_NCPU;
> }
> diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
> index d168291..801a4ad 100644
> --- a/include/hw/arm/virt.h
> +++ b/include/hw/arm/virt.h
> @@ -60,6 +60,7 @@ enum {
> VIRT_GIC_V2M,
> VIRT_GIC_ITS,
> VIRT_GIC_REDIST,
> + VIRT_GIC_REDIST2,
> VIRT_UART,
> VIRT_MMIO,
> VIRT_RTC,
>
--
Shannon
