Re: [RFC PATCH 07/12] hw/acpi/aml-build: add processor hierarchy node structure

[Ying Fang]

On 9/17/2020 4:27 PM, Andrew Jones wrote:
> On Thu, Sep 17, 2020 at 11:20:28AM +0800, Ying Fang wrote:
> > Add the processor hierarchy node structures to build ACPI information
> > for CPU topology. Three helpers are introduced:
> >
> > (1) build_socket_hierarchy for socket description structure
> > (2) build_processor_hierarchy for processor description structure
> > (3) build_smt_hierarchy for thread (logic processor) description structure
> >
> > Signed-off-by: Ying Fang <fangying1@huawei.com>
> > Signed-off-by: Henglong Fan <fanhenglong@huawei.com>
> > ---
> >   hw/acpi/aml-build.c         | 37 +++++++++++++++++++++++++++++++++++++
> >   include/hw/acpi/aml-build.h |  7 +++++++
> >   2 files changed, 44 insertions(+)
> >
> > diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
> > index f6fbc9b95d..13eb6e1345 100644
> > --- a/hw/acpi/aml-build.c
> > +++ b/hw/acpi/aml-build.c
> > @@ -1754,6 +1754,43 @@ void build_slit(GArray *table_data, BIOSLinker *linker, 
> > MachineState *ms)
> >                    table_data->len - slit_start, 1, NULL, NULL);
> >   }
> >   
> > +/*
> > + * ACPI 6.3: 5.2.29.1 Processor hierarchy node structure (Type 0)
> > + */
> > +void build_socket_hierarchy(GArray *tbl, uint32_t parent, uint32_t id)
> > +{
> > +    build_append_byte(tbl, 0);          /* Type 0 - processor */
> > +    build_append_byte(tbl, 20);         /* Length, no private resources */
> > +    build_append_int_noprefix(tbl, 0, 2);  /* Reserved */
> > +    build_append_int_noprefix(tbl, 1, 4);  /* Flags: Physical package */
> > +    build_append_int_noprefix(tbl, parent, 4);  /* Parent */
> > +    build_append_int_noprefix(tbl, id, 4);     /* ACPI processor ID */
> > +    build_append_int_noprefix(tbl, 0, 4);  /* Number of private resources */
> > +}
> > +
> > +void build_processor_hierarchy(GArray *tbl, uint32_t flags,
> > +                               uint32_t parent, uint32_t id)
> > +{
> > +    build_append_byte(tbl, 0);          /* Type 0 - processor */
> > +    build_append_byte(tbl, 20);         /* Length, no private resources */
> > +    build_append_int_noprefix(tbl, 0, 2);      /* Reserved */
> > +    build_append_int_noprefix(tbl, flags, 4);  /* Flags */
> > +    build_append_int_noprefix(tbl, parent, 4); /* Parent */
> > +    build_append_int_noprefix(tbl, id, 4);     /* ACPI processor ID */
> > +    build_append_int_noprefix(tbl, 0, 4);  /* Number of private resources */
> > +}
>
> I see you took this from
> https://patchwork.ozlabs.org/project/qemu-devel/patch/20180704124923.32483-6-drjones@redhat.com/
> (even though you neglected to mention that)
>
> I've tweaked my implementation of it slightly per Igor's comments for the
> refresh. See build_processor_hierarchy_node() in
> https://github.com/rhdrjones/qemu/commit/439b38d67ca1f2cbfa5b9892a822b651ebd05c11
Ok, I will sync with your work and test it.
> > +
> > +void build_smt_hierarchy(GArray *tbl, uint32_t parent, uint32_t id)
> > +{
> > +    build_append_byte(tbl, 0);            /* Type 0 - processor */
> > +    build_append_byte(tbl, 20);           /* Length, add private resources */
> > +    build_append_int_noprefix(tbl, 0, 2); /* Reserved */
> > +    build_append_int_noprefix(tbl, 0x0e, 4);    /* Processor is a thread */
> > +    build_append_int_noprefix(tbl, parent , 4); /* parent */
> > +    build_append_int_noprefix(tbl, id, 4);      /* ACPI processor ID */
> > +    build_append_int_noprefix(tbl, 0, 4);       /* Num of private resources */
> > +}
> > +
> >   /* build rev1/rev3/rev5.1 FADT */
> >   void build_fadt(GArray *tbl, BIOSLinker *linker, const AcpiFadtData *f,
> >                   const char *oem_id, const char *oem_table_id)
> > diff --git a/include/hw/acpi/aml-build.h b/include/hw/acpi/aml-build.h
> > index d27da03d64..ff4c6a38f3 100644
> > --- a/include/hw/acpi/aml-build.h
> > +++ b/include/hw/acpi/aml-build.h
> > @@ -435,6 +435,13 @@ void build_srat_memory(AcpiSratMemoryAffinity *numamem, 
> > uint64_t base,
> >   
> >   void build_slit(GArray *table_data, BIOSLinker *linker, MachineState *ms);
> >   
> > +void build_socket_hierarchy(GArray *tbl, uint32_t parent, uint32_t id);
> > +
> > +void build_processor_hierarchy(GArray *tbl, uint32_t flags,
> > +                               uint32_t parent, uint32_t id);
> > +
> > +void build_smt_hierarchy(GArray *tbl, uint32_t parent, uint32_t id);
>
> Why add build_socket_hierarchy() and build_smt_hierarchy() ?

To distinguish between socket, core and thread topology level,
build_socket_hierarchy and build_smt_hierarchy are introduced.
They will make the code logical in built_pptt much more much 
straightforward I think.

> > +
> >   void build_fadt(GArray *tbl, BIOSLinker *linker, const AcpiFadtData *f,
> >                   const char *oem_id, const char *oem_table_id);
> >   
> > --
> > 2.23.0
>
> Thanks,
> drew
>
> .