Re: [RFC PATCH 5/5] hw/arm/virt-acpi-build: add PPTT table

[Ying Fang <fangying1@huawei.com>]

On 2/25/2021 7:38 PM, Andrew Jones wrote:
> 
> This is just [*] with some minor code changes
> 
> [*] https://github.com/rhdrjones/qemu/commit/439b38d67ca1f2cbfa5b9892a822b651ebd05c11
> 
> so it's disappointing that my name is nowhere to be found on it.
> 
> Also, the explanation of the DT and ACPI differences has been
> dropped from the commit message of [*]. I'm not sure why.
> 

Will fix that. I will add SOB of you then you can help to comment on it.

> Thanks,
> drew
> 
> On Thu, Feb 25, 2021 at 04:56:27PM +0800, Ying Fang wrote:
>> Add the Processor Properties Topology Table (PPTT) to present
>> CPU topology information to the guest. A three-level cpu
>> topology is built in accord with the linux kernel currently does.
>>
>> Tested-by: Jiajie Li <lijiajie11@huawei.com>
>> Signed-off-by: Ying Fang <fangying1@huawei.com>
>> ---
>>   hw/arm/virt-acpi-build.c | 50 ++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 50 insertions(+)
>>
>> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
>> index bb91152fe2..38d50ce66c 100644
>> --- a/hw/arm/virt-acpi-build.c
>> +++ b/hw/arm/virt-acpi-build.c
>> @@ -436,6 +436,50 @@ build_srat(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>>                    vms->oem_table_id);
>>   }
>>   
>> +static void
>> +build_pptt(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>> +{
>> +    int pptt_start = table_data->len;
>> +    int uid = 0, cpus = 0, socket = 0;
>> +    MachineState *ms = MACHINE(vms);
>> +    unsigned int smp_cores = ms->smp.cores;
>> +    unsigned int smp_threads = ms->smp.threads;
>> +
>> +    acpi_data_push(table_data, sizeof(AcpiTableHeader));
>> +
>> +    for (socket = 0; cpus < ms->possible_cpus->len; socket++) {
>> +        uint32_t socket_offset = table_data->len - pptt_start;
>> +        int core;
>> +
>> +        build_socket_hierarchy(table_data, 0, socket);
>> +
>> +        for (core = 0; core < smp_cores; core++) {
>> +            uint32_t core_offset = table_data->len - pptt_start;
>> +            int thread;
>> +
>> +            if (smp_threads <= 1) {
>> +                build_processor_hierarchy(table_data,
>> +                                          ACPI_PPTT_ACPI_PROCESSOR_ID_VALID |
>> +                                          ACPI_PPTT_ACPI_LEAF_NODE,
>> +                                          socket_offset, uid++);
>> +             } else {
>> +                build_processor_hierarchy(table_data,
>> +                                          ACPI_PPTT_ACPI_PROCESSOR_ID_VALID,
>> +                                          socket_offset, core);
>> +                for (thread = 0; thread < smp_threads; thread++) {
>> +                    build_thread_hierarchy(table_data, core_offset, uid++);
>> +                }
>> +             }
>> +        }
>> +        cpus += smp_cores * smp_threads;
>> +    }
>> +
>> +    build_header(linker, table_data,
>> +                 (void *)(table_data->data + pptt_start), "PPTT",
>> +                 table_data->len - pptt_start, 2,
>> +                 vms->oem_id, vms->oem_table_id);
>> +}
>> +
>>   /* GTDT */
>>   static void
>>   build_gtdt(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>> @@ -688,6 +732,7 @@ void virt_acpi_build(VirtMachineState *vms, AcpiBuildTables *tables)
>>       unsigned dsdt, xsdt;
>>       GArray *tables_blob = tables->table_data;
>>       MachineState *ms = MACHINE(vms);
>> +    bool cpu_topology_enabled = !vmc->no_cpu_topology;
>>   
>>       table_offsets = g_array_new(false, true /* clear */,
>>                                           sizeof(uint32_t));
>> @@ -707,6 +752,11 @@ void virt_acpi_build(VirtMachineState *vms, AcpiBuildTables *tables)
>>       acpi_add_table(table_offsets, tables_blob);
>>       build_madt(tables_blob, tables->linker, vms);
>>   
>> +    if (ms->smp.cpus > 1 && cpu_topology_enabled) {
>> +        acpi_add_table(table_offsets, tables_blob);
>> +        build_pptt(tables_blob, tables->linker, vms);
>> +    }
>> +
>>       acpi_add_table(table_offsets, tables_blob);
>>       build_gtdt(tables_blob, tables->linker, vms);
>>   
>> -- 
>> 2.23.0
>>
>>
> 
> .
>