Re: [Qemu-arm] [Qemu-devel] [PATCH] arm: virt-acpi: each MADT.GICC entry as enabled unconditionally

[Igor Mammedov <imammedo@redhat.com>]

On Sat, 30 Jan 2016 09:50:30 +0800
Shannon Zhao <zhaoshenglong@huawei.com> wrote:

> On 2016/1/29 22:24, Igor Mammedov wrote:
> > in current impl. condition
> > 
> > build_madt() {
> >   ...
> >   if (test_bit(i, cpuinfo->found_cpus))
> > 
> > is always true since loop handles only present CPUs
> > in range [0..smp_cpus).
> > But to fill usless cpuinfo->found_cpus we do unnecessary
> > scan over QOM tree to find the same CPUs.
> > So mark GICC as present always and drop not needed
> > code that fills cpuinfo->found_cpus.
> > 
> > Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> > ---
> > It's just simple cleanup but I'm trying to generalize
> > a bit CPU related ACPI tables and as part of it get rid
> > of found_cpus bitmap and if possible cpu_index usage
> > in ACPI parts of code.
> > ---
> >  hw/arm/virt-acpi-build.c | 26 +++-----------------------
> >  1 file changed, 3 insertions(+), 23 deletions(-)
> > 
> > diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> > index 87fbe7c..3ed39fc 100644
> > --- a/hw/arm/virt-acpi-build.c
> > +++ b/hw/arm/virt-acpi-build.c
> > @@ -46,20 +46,6 @@
> >  #define ARM_SPI_BASE 32
> >  #define ACPI_POWER_BUTTON_DEVICE "PWRB"
> >  
> > -typedef struct VirtAcpiCpuInfo {
> > -    DECLARE_BITMAP(found_cpus, VIRT_ACPI_CPU_ID_LIMIT);  
> The definition of VIRT_ACPI_CPU_ID_LIMIT should be removed as well.
Ok, I'll send v2 with fixup.

> 
> Otherwise:
> 
> Reviewed-by: Shannon Zhao <shannon.zhao@linaro.org>
> 
> > -} VirtAcpiCpuInfo;
> > -
> > -static void virt_acpi_get_cpu_info(VirtAcpiCpuInfo *cpuinfo)
> > -{
> > -    CPUState *cpu;
> > -
> > -    memset(cpuinfo->found_cpus, 0, sizeof cpuinfo->found_cpus);
> > -    CPU_FOREACH(cpu) {
> > -        set_bit(cpu->cpu_index, cpuinfo->found_cpus);
> > -    }
> > -}
> > -
> >  static void acpi_dsdt_add_cpus(Aml *scope, int smp_cpus)
> >  {
> >      uint16_t i;
> > @@ -458,8 +444,7 @@ build_gtdt(GArray *table_data, GArray *linker)
> >  
> >  /* MADT */
> >  static void
> > -build_madt(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info,
> > -           VirtAcpiCpuInfo *cpuinfo)
> > +build_madt(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info)
> >  {
> >      int madt_start = table_data->len;
> >      const MemMapEntry *memmap = guest_info->memmap;
> > @@ -489,9 +474,7 @@ build_madt(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info,
> >          gicc->cpu_interface_number = i;
> >          gicc->arm_mpidr = armcpu->mp_affinity;
> >          gicc->uid = i;
> > -        if (test_bit(i, cpuinfo->found_cpus)) {
> > -            gicc->flags = cpu_to_le32(ACPI_GICC_ENABLED);
> > -        }
> > +        gicc->flags = cpu_to_le32(ACPI_GICC_ENABLED);
> >      }
> >  
> >      if (guest_info->gic_version == 3) {
> > @@ -599,11 +582,8 @@ void virt_acpi_build(VirtGuestInfo *guest_info, AcpiBuildTables *tables)
> >  {
> >      GArray *table_offsets;
> >      unsigned dsdt, rsdt;
> > -    VirtAcpiCpuInfo cpuinfo;
> >      GArray *tables_blob = tables->table_data;
> >  
> > -    virt_acpi_get_cpu_info(&cpuinfo);
> > -
> >      table_offsets = g_array_new(false, true /* clear */,
> >                                          sizeof(uint32_t));
> >  
> > @@ -630,7 +610,7 @@ void virt_acpi_build(VirtGuestInfo *guest_info, AcpiBuildTables *tables)
> >      build_fadt(tables_blob, tables->linker, dsdt);
> >  
> >      acpi_add_table(table_offsets, tables_blob);
> > -    build_madt(tables_blob, tables->linker, guest_info, &cpuinfo);
> > +    build_madt(tables_blob, tables->linker, guest_info);
> >  
> >      acpi_add_table(table_offsets, tables_blob);
> >      build_gtdt(tables_blob, tables->linker);  
>