Re: [PATCH 2/3] hw/acpi/cpu_hotplug: Rename 'parent' MemoryRegion as 'container'

[Philippe Mathieu-Daudé]

On 28/2/23 22:43, Michael S. Tsirkin wrote:
> On Fri, Feb 03, 2023 at 05:30:20PM +0100, Philippe Mathieu-Daudé wrote:
> > No logical change, rename for clarity.
> >
> > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>
> Can't say container is clearer. If we are changing things
> I'd like to see a real improvement.

QOM API usually use 'parent' to indicate the inheritance / hierarchy
between object.
Memory API uses 'container', in particular when used with
memory_region_add_subregion().

I still believe this is a worthwhile change as API style cleanup,
but I agree the commit description lacks this explanation.

> > ---
> >   hw/acpi/acpi-cpu-hotplug-stub.c |  2 +-
> >   hw/acpi/cpu_hotplug.c           | 10 +++++-----
> >   hw/acpi/piix4.c                 | 10 +++++-----
> >   include/hw/acpi/cpu_hotplug.h   |  2 +-
> >   4 files changed, 12 insertions(+), 12 deletions(-)
> >
> > diff --git a/hw/acpi/acpi-cpu-hotplug-stub.c b/hw/acpi/acpi-cpu-hotplug-stub.c
> > index b590ad57e1..cbd7a6ec00 100644
> > --- a/hw/acpi/acpi-cpu-hotplug-stub.c
> > +++ b/hw/acpi/acpi-cpu-hotplug-stub.c
> > @@ -13,7 +13,7 @@ void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe,
> >       return;
> >   }
> >   
> > -void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner,
> > +void legacy_acpi_cpu_hotplug_init(MemoryRegion *container, Object *owner,
> >                                     AcpiCpuHotplug *gpe, uint16_t base)
> >   {
> >       return;
> > diff --git a/hw/acpi/cpu_hotplug.c b/hw/acpi/cpu_hotplug.c
> > index 3cfa4f45dc..636e985c50 100644
> > --- a/hw/acpi/cpu_hotplug.c
> > +++ b/hw/acpi/cpu_hotplug.c
> > @@ -81,14 +81,14 @@ void legacy_acpi_cpu_plug_cb(HotplugHandler *hotplug_dev, 
> > AcpiCpuHotplug *gpe,
> >       acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS);
> >   }
> >   
> > -void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner,
> > +void legacy_acpi_cpu_hotplug_init(MemoryRegion *container, Object *owner,
> >                                     AcpiCpuHotplug *gpe, uint16_t base)
> >   {
> >       CPUState *cpu;
> >   
> >       memory_region_init_io(&gpe->io, owner, &AcpiCpuHotplug_ops,
> >                             gpe, "acpi-cpu-hotplug", ACPI_GPE_PROC_LEN);
> > -    memory_region_add_subregion(parent, base, &gpe->io);
> > +    memory_region_add_subregion(container, base, &gpe->io);
> >       gpe->device = owner;
> >   
> >       CPU_FOREACH(cpu) {
> > @@ -100,10 +100,10 @@ void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe,
> >                                   CPUHotplugState *cpuhp_state,
> >                                   uint16_t io_port)
> >   {
> > -    MemoryRegion *parent = pci_address_space_io(PCI_DEVICE(gpe->device));
> > +    MemoryRegion *container = pci_address_space_io(PCI_DEVICE(gpe->device));
> >   
> > -    memory_region_del_subregion(parent, &gpe->io);
> > -    cpu_hotplug_hw_init(parent, gpe->device, cpuhp_state, io_port);
> > +    memory_region_del_subregion(container, &gpe->io);
> > +    cpu_hotplug_hw_init(container, gpe->device, cpuhp_state, io_port);
> >   }
> >   
> >   void build_legacy_cpu_hotplug_aml(Aml *ctx, MachineState *machine,
> > diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
> > index c702d83f27..5595fe5be5 100644
> > --- a/hw/acpi/piix4.c
> > +++ b/hw/acpi/piix4.c
> > @@ -555,15 +555,15 @@ static void piix4_set_cpu_hotplug_legacy(Object *obj, 
> > bool value, Error **errp)
> >       s->cpu_hotplug_legacy = value;
> >   }
> >   
> > -static void piix4_acpi_system_hot_add_init(MemoryRegion *parent,
> > +static void piix4_acpi_system_hot_add_init(MemoryRegion *container,
> >                                              PCIBus *bus, PIIX4PMState *s)
> >   {
> >       memory_region_init_io(&s->io_gpe, OBJECT(s), &piix4_gpe_ops, s,
> >                             "acpi-gpe0", GPE_LEN);
> > -    memory_region_add_subregion(parent, GPE_BASE, &s->io_gpe);
> > +    memory_region_add_subregion(container, GPE_BASE, &s->io_gpe);
> >   
> >       if (s->use_acpi_hotplug_bridge || s->use_acpi_root_pci_hotplug) {
> > -        acpi_pcihp_init(OBJECT(s), &s->acpi_pci_hotplug, bus, parent,
> > +        acpi_pcihp_init(OBJECT(s), &s->acpi_pci_hotplug, bus, container,
> >                           s->use_acpi_hotplug_bridge, ACPI_PCIHP_ADDR_PIIX4);
> >       }
> >   
> > @@ -571,11 +571,11 @@ static void piix4_acpi_system_hot_add_init(MemoryRegion *parent,
> >       object_property_add_bool(OBJECT(s), "cpu-hotplug-legacy",
> >                                piix4_get_cpu_hotplug_legacy,
> >                                piix4_set_cpu_hotplug_legacy);
> > -    legacy_acpi_cpu_hotplug_init(parent, OBJECT(s), &s->gpe,
> > +    legacy_acpi_cpu_hotplug_init(container, OBJECT(s), &s->gpe,
> >                                    PIIX4_CPU_HOTPLUG_IO_BASE);
> >   
> >       if (s->acpi_memory_hotplug.is_enabled) {
> > -        acpi_memory_hotplug_init(parent, OBJECT(s), &s->acpi_memory_hotplug,
> > +        acpi_memory_hotplug_init(container, OBJECT(s), &s->acpi_memory_hotplug,
> >                                    ACPI_MEMORY_HOTPLUG_BASE);
> >       }
> >   }
> > diff --git a/include/hw/acpi/cpu_hotplug.h b/include/hw/acpi/cpu_hotplug.h
> > index 99c11b7151..5ff24ec417 100644
> > --- a/include/hw/acpi/cpu_hotplug.h
> > +++ b/include/hw/acpi/cpu_hotplug.h
> > @@ -28,7 +28,7 @@ typedef struct AcpiCpuHotplug {
> >   void legacy_acpi_cpu_plug_cb(HotplugHandler *hotplug_dev, AcpiCpuHotplug *gpe,
> >                                DeviceState *dev, Error **errp);
> >   
> > -void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner,
> > +void legacy_acpi_cpu_hotplug_init(MemoryRegion *container, Object *owner,
> >                                     AcpiCpuHotplug *gpe, uint16_t base);
> >   
> >   void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe,
> > --
> > 2.38.1