Re: [PATCH v5 11/16] target/i386: Load apicid model specific handlers from X86CPUDefinition

[Babu Moger]

On 3/9/20 9:49 AM, Igor Mammedov wrote:
> On Tue, 03 Mar 2020 13:58:03 -0600
> Babu Moger <address@hidden> wrote:
> 
>> Load the model specific handlers if available or else default handlers
>> will be loaded. Add the model specific handlers if apicid decoding
>> differs from the standard sequential numbering.
>>
> 
> this is still the old version of the patch and hadn't addressed feedback from 
> v4

Yes. I was confused little bit about it. Will fix it.

> 
>> Signed-off-by: Babu Moger <address@hidden>
>> ---
>>  target/i386/cpu.c |   34 ++++++++++++++++++++++++++++++++++
>>  target/i386/cpu.h |    1 +
>>  2 files changed, 35 insertions(+)
>>
>> diff --git a/target/i386/cpu.c b/target/i386/cpu.c
>> index c75cf744ab..f33d8b77f5 100644
>> --- a/target/i386/cpu.c
>> +++ b/target/i386/cpu.c
>> @@ -51,6 +51,7 @@
>>  #include "sysemu/sysemu.h"
>>  #include "sysemu/tcg.h"
>>  #include "hw/qdev-properties.h"
>> +#include "hw/i386/x86.h"
> this dependency shouldn't be here, see below

ok.

> 
>>  #include "hw/i386/topology.h"
>>  #ifndef CONFIG_USER_ONLY
>>  #include "exec/address-spaces.h"
> [...]
>> +void cpu_x86_init_apicid_fns(MachineState *machine)
> it should be something like:
>   x86_use_epyc_apic_id_encoding(char *cpu_type)
> try to avoid pulling in unnecessary dependency on Machine into cpu.c

Ok.

> 
>> +{
>> +    X86CPUClass *xcc = 
>> X86_CPU_CLASS(object_class_by_name(machine->cpu_type));
>> +    X86CPUModel *model = xcc->model;
>> +    X86CPUDefinition *def = model->cpudef;
>> +    X86MachineState *x86ms = X86_MACHINE(machine);
>> +
>> +    if (def) {
>> +        if (def->apicid_from_cpu_idx) {
>> +            x86ms->apicid_from_cpu_idx = def->apicid_from_cpu_idx;
>> +        }
>> +        if (def->topo_ids_from_apicid) {
>> +            x86ms->topo_ids_from_apicid = def->topo_ids_from_apicid;
>> +        }
>> +        if (def->apicid_from_topo_ids) {
>> +            x86ms->apicid_from_topo_ids = def->apicid_from_topo_ids;
>> +        }
>> +        if (def->apicid_pkg_offset) {
>> +            x86ms->apicid_pkg_offset = def->apicid_pkg_offset;
>> +        }
>> +    }
>> +}
> 
> It was suggested to move defaults initialization to x86_machine_class_init()

ok.  We don't need the above changes. I will use the boolean as you
suggested and call this function in x86_cpus_init() to initialize the EPYC
specific handler. Something similar like this below..

x86_use_epyc_apic_id_encoding(char *cpu_type)
{
      X86CPUClass *xcc = ... cpu_type ...
      return xcc->model->cpudef->use_epyc_apic_id_encoding
}

x86_cpus_init()
{
 if (x86_use_epyc_apic_id_encoding(ms->cpu_type)) {
            x86ms->apicid_from_cpu_idx = ...epyc...
            x86ms->topo_ids_from_apicid = ...epyc...
            x86ms->apicid_from_topo_ids = ...epyc...
            x86ms->apicid_pkg_offset = ...epyc...
    }
}

Sounds right?

> 
> as was suggested at 
> [PATCH v4 12/16] hw/i386: Use the apicid handlers from X86MachineState
> and acked by Eduardo
> 
>> +
>>  static CPUCaches epyc_cache_info = {
>>      .l1d_cache = &(CPUCacheInfo) {
>>          .type = DATA_CACHE,
>> diff --git a/target/i386/cpu.h b/target/i386/cpu.h
>> index 20abbda647..34f0d994ef 100644
>> --- a/target/i386/cpu.h
>> +++ b/target/i386/cpu.h
>> @@ -1895,6 +1895,7 @@ void cpu_clear_apic_feature(CPUX86State *env);
>>  void host_cpuid(uint32_t function, uint32_t count,
>>                  uint32_t *eax, uint32_t *ebx, uint32_t *ecx, uint32_t *edx);
>>  void host_vendor_fms(char *vendor, int *family, int *model, int *stepping);
>> +void cpu_x86_init_apicid_fns(MachineState *machine);
>>  
>>  /* helper.c */
>>  bool x86_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
>>
>