On Wed, 18 May 2022 17:21:40 +0800
Gavin Shan <gs...@redhat.com> wrote:
> The {socket, cluster, core} IDs detected from Linux guest aren't
> matching with what have been provided in PPTT. The flag used for
> 'ACPI Processor ID valid' is missed for {socket, cluster, core}
> nodes.
To permit this flag set on no leaf nodes we have to have
a corresponding containers built for them in DSDT so that
'ACPI Processor ID' could be matched with containers '_UID's.
If we don not build such containers then setting this flag is
not correct. And I don't recall QEMU building CPU hierarchy
in DSDT.
> In this case, Linux guest takes the offset between the
> node and PPTT header as the corresponding IDs, as the following
> logs show.
perhaps it's kernel which should be fixed to handle
not set 'ACPI Processor ID valid' correctly.
>
> /home/gavin/sandbox/qemu.main/build/qemu-system-aarch64 \
> -accel kvm -machine virt,gic-version=host -cpu host \
> -smp 8,sockets=2,clusters=2,cores=2,threads=1
> :
>
> # cd /sys/devices/system/cpu
> # for i in `seq 0 15`; do cat cpu$i/topology/physical_package_id; done
> 36 36 36 36 36 36 36 36
> 336 336 336 336 336 336 336 336
> # for i in `seq 0 15`; do cat cpu$i/topology/cluster_id; done
> 56 56 56 56 196 196 196 196
> 356 356 356 356 496 496 496 496
> # for i in `seq 0 15`; do cat cpu$i/topology/core_id; done
> 76 76 136 136 216 216 276 276
> 376 376 436 436 516 516 576 576
>
> This fixes the issue by setting 'ACPI Processor ID valid' flag for
> {socket, cluster, core} nodes. With this applied, the IDs are exactly
> what have been provided in PPTT.
>
> # for i in `seq 0 15`; do cat cpu$i/topology/physical_package_id; done
> 0 0 0 0 0 0 0 0
> 1 1 1 1 1 1 1 1
> # for i in `seq 0 15`; do cat cpu$i/topology/cluster_id; done
> 0 0 0 0 1 1 1 1
> 0 0 0 0 1 1 1 1
> # for i in `seq 0 15`; do cat cpu$i/topology/core_id; done
> 0 0 1 1 0 0 1 1
> 0 0 1 1 0 0 1 1
>
> Signed-off-by: Gavin Shan <gs...@redhat.com>
> ---
> hw/acpi/aml-build.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
> index e6bfac95c7..89f191fd3b 100644
> --- a/hw/acpi/aml-build.c
> +++ b/hw/acpi/aml-build.c
> @@ -2026,7 +2026,8 @@ void build_pptt(GArray *table_data, BIOSLinker *linker,
> MachineState *ms,
> core_id = -1;
> socket_offset = table_data->len - pptt_start;
> build_processor_hierarchy_node(table_data,
> - (1 << 0), /* Physical package */
> + (1 << 0) | /* Physical package */
> + (1 << 1), /* ACPI Processor ID valid */
> 0, socket_id, NULL, 0);
> }
>
> @@ -2037,7 +2038,8 @@ void build_pptt(GArray *table_data, BIOSLinker *linker,
> MachineState *ms,
> core_id = -1;
> cluster_offset = table_data->len - pptt_start;
> build_processor_hierarchy_node(table_data,
> - (0 << 0), /* Not a physical package */
> + (0 << 0) | /* Not a physical package */
> + (1 << 1), /* ACPI Processor ID valid */
> socket_offset, cluster_id, NULL, 0);
> }
> } else {
> @@ -2055,7 +2057,8 @@ void build_pptt(GArray *table_data, BIOSLinker *linker,
> MachineState *ms,
> core_id = cpus->cpus[n].props.core_id;
> core_offset = table_data->len - pptt_start;
> build_processor_hierarchy_node(table_data,
> - (0 << 0), /* Not a physical package */
> + (0 << 0) | /* Not a physical package */
> + (1 << 1), /* ACPI Processor ID valid */
> cluster_offset, core_id, NULL, 0);
> }
>
