Re: [Qemu-devel] [PATCH v4 08/10] pc: acpi: drop cpu->found_cpus bitmap

[Marcel Apfelbaum <marcel@redhat.com>]

On 02/26/2016 03:59 PM, Igor Mammedov wrote:
> cpu->found_cpus bitmap is used for setting present
> flag in CPON AML package. But it takes a bunch of code
> to fill bitmap and could be simplified by getting
> presense info from possible CPUs list directly.
>
> So drop cpu->found_cpus bitmap and unroll possible
> CPUs list into APIC index array at the place where
> CPUON AML package is created.
>
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> ---
>   hw/i386/acpi-build.c | 53 ++++++++++++++--------------------------------------
>   1 file changed, 14 insertions(+), 39 deletions(-)
>
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index df7e6df..48240e0 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -76,10 +76,6 @@
>   #define ACPI_BUILD_DPRINTF(fmt, ...)
>   #endif
>
> -typedef struct AcpiCpuInfo {
> -    DECLARE_BITMAP(found_cpus, ACPI_CPU_HOTPLUG_ID_LIMIT);
> -} AcpiCpuInfo;
> -
>   typedef struct AcpiMcfgInfo {
>       uint64_t mcfg_base;
>       uint32_t mcfg_size;
> @@ -121,31 +117,6 @@ typedef struct AcpiBuildPciBusHotplugState {
>       bool pcihp_bridge_en;
>   } AcpiBuildPciBusHotplugState;
>
> -static
> -int acpi_add_cpu_info(Object *o, void *opaque)
> -{
> -    AcpiCpuInfo *cpu = opaque;
> -    uint64_t apic_id;
> -
> -    if (object_dynamic_cast(o, TYPE_CPU)) {
> -        apic_id = object_property_get_int(o, "apic-id", NULL);
> -        assert(apic_id < ACPI_CPU_HOTPLUG_ID_LIMIT);
> -
> -        set_bit(apic_id, cpu->found_cpus);
> -    }
> -
> -    object_child_foreach(o, acpi_add_cpu_info, opaque);
> -    return 0;
> -}
> -
> -static void acpi_get_cpu_info(AcpiCpuInfo *cpu)
> -{
> -    Object *root = object_get_root();
> -
> -    memset(cpu->found_cpus, 0, sizeof cpu->found_cpus);
> -    object_child_foreach(root, acpi_add_cpu_info, cpu);
> -}
> -
>   static void acpi_get_pm_info(AcpiPmInfo *pm)
>   {
>       Object *piix = piix4_pm_find();
> @@ -966,9 +937,9 @@ static Aml *build_crs(PCIHostState *host,
>   }
>
>   static void build_processor_devices(Aml *sb_scope, MachineState *machine,
> -                                    AcpiCpuInfo *cpu, AcpiPmInfo *pm)
> +                                    AcpiPmInfo *pm)
>   {
> -    int i;
> +    int i, apic_idx;
>       Aml *dev;
>       Aml *crs;
>       Aml *pkg;
> @@ -1011,6 +982,7 @@ static void build_processor_devices(Aml *sb_scope, MachineState *machine,
>           int apic_id = apic_ids->cpus[i].arch_id;
>
>           assert(apic_id < ACPI_CPU_HOTPLUG_ID_LIMIT);
> +

Unneeded chunk, not really a big issue :)


Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>

Thanks,
Marcel

>           dev = aml_processor(apic_id, 0, 0, "CP%.02X", apic_id);
>
>           method = aml_method("_MAT", 0, AML_NOTSERIALIZED);
> @@ -1059,9 +1031,14 @@ static void build_processor_devices(Aml *sb_scope, MachineState *machine,
>       pkg = pcms->apic_id_limit <= 255 ? aml_package(pcms->apic_id_limit) :
>                                          aml_varpackage(pcms->apic_id_limit);
>
> -    for (i = 0; i < pcms->apic_id_limit; i++) {
> -        uint8_t b = test_bit(i, cpu->found_cpus) ? 0x01 : 0x00;
> -        aml_append(pkg, aml_int(b));
> +    for (i = 0, apic_idx = 0; i < apic_ids->len; i++) {
> +        int apic_id = apic_ids->cpus[i].arch_id;
> +
> +        for (; apic_idx < apic_id; apic_idx++) {
> +            aml_append(pkg, aml_int(0));
> +        }
> +        aml_append(pkg, aml_int(apic_ids->cpus[i].cpu ? 1 : 0));
> +        apic_idx = apic_id + 1;
>       }
>       aml_append(sb_scope, aml_name_decl(CPU_ON_BITMAP, pkg));
>       g_free(apic_ids);
> @@ -1952,7 +1929,7 @@ static Aml *build_q35_osc_method(void)
>
>   static void
>   build_dsdt(GArray *table_data, GArray *linker,
> -           AcpiCpuInfo *cpu, AcpiPmInfo *pm, AcpiMiscInfo *misc,
> +           AcpiPmInfo *pm, AcpiMiscInfo *misc,
>              PcPciInfo *pci, MachineState *machine)
>   {
>       CrsRangeEntry *entry;
> @@ -2259,7 +2236,7 @@ build_dsdt(GArray *table_data, GArray *linker,
>
>       sb_scope = aml_scope("\\_SB");
>       {
> -        build_processor_devices(sb_scope, machine, cpu, pm);
> +        build_processor_devices(sb_scope, machine, pm);
>
>           build_memory_devices(sb_scope, nr_mem, pm->mem_hp_io_base,
>                                pm->mem_hp_io_len);
> @@ -2613,7 +2590,6 @@ void acpi_build(AcpiBuildTables *tables, MachineState *machine)
>       PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
>       GArray *table_offsets;
>       unsigned facs, dsdt, rsdt, fadt;
> -    AcpiCpuInfo cpu;
>       AcpiPmInfo pm;
>       AcpiMiscInfo misc;
>       AcpiMcfgInfo mcfg;
> @@ -2623,7 +2599,6 @@ void acpi_build(AcpiBuildTables *tables, MachineState *machine)
>       GArray *tables_blob = tables->table_data;
>       AcpiSlicOem slic_oem = { .id = NULL, .table_id = NULL };
>
> -    acpi_get_cpu_info(&cpu);
>       acpi_get_pm_info(&pm);
>       acpi_get_misc_info(&misc);
>       acpi_get_pci_info(&pci);
> @@ -2647,7 +2622,7 @@ void acpi_build(AcpiBuildTables *tables, MachineState *machine)
>
>       /* DSDT is pointed to by FADT */
>       dsdt = tables_blob->len;
> -    build_dsdt(tables_blob, tables->linker, &cpu, &pm, &misc, &pci, machine);
> +    build_dsdt(tables_blob, tables->linker, &pm, &misc, &pci, machine);
>
>       /* Count the size of the DSDT and SSDT, we will need it for legacy
>        * sizing of ACPI tables.
>