Re: [Qemu-devel] [PATCH v4 1/2] machine: add default_ram_size to machine class

[Marcel Apfelbaum <marcel.apfelbaum@gmail.com>]

On 03/05/2015 01:56 PM, Nikunj A Dadhania wrote:
> Machines types can have different requirement for default ram
> size. Introduce a member in the machine class and set the current
> default_ram_size to 128MB.
>
> For QEMUMachine types override the value during the registration of
> the machine and for MachineClass introduce the generic class init
> setting the default_ram_size.
>
> Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
> ---
>   hw/core/machine.c   | 11 +++++++++++
>   include/hw/boards.h |  1 +
>   vl.c                | 30 ++++++++++++++++--------------
>   3 files changed, 28 insertions(+), 14 deletions(-)
>
> diff --git a/hw/core/machine.c b/hw/core/machine.c
> index fbd91be..533a04f 100644
> --- a/hw/core/machine.c
> +++ b/hw/core/machine.c
> @@ -403,11 +403,22 @@ bool machine_usb(MachineState *machine)
>       return machine->usb;
>   }
>
> +/* Default 128 MB as guest ram size */
> +#define MACHINE_DEFAULT_RAM_SIZE (1UL << 27)
> +
> +static void machine_class_init(ObjectClass *oc, void *data)
> +{
> +    MachineClass *mc = MACHINE_CLASS(oc);
> +
> +    mc->default_ram_size = MACHINE_DEFAULT_RAM_SIZE;
> +}
> +
>   static const TypeInfo machine_info = {
>       .name = TYPE_MACHINE,
>       .parent = TYPE_OBJECT,
>       .abstract = true,
>       .class_size = sizeof(MachineClass),
> +    .class_init    = machine_class_init,
>       .instance_size = sizeof(MachineState),
>       .instance_init = machine_initfn,
>       .instance_finalize = machine_finalize,
> diff --git a/include/hw/boards.h b/include/hw/boards.h
> index 3ddc449..b2b4698 100644
> --- a/include/hw/boards.h
> +++ b/include/hw/boards.h
> @@ -108,6 +108,7 @@ struct MachineClass {
>       const char *default_display;
>       GlobalProperty *compat_props;
>       const char *hw_version;
> +    ram_addr_t default_ram_size;
>
>       HotplugHandler *(*get_hotplug_handler)(MachineState *machine,
>                                              DeviceState *dev);
> diff --git a/vl.c b/vl.c
> index 801d487..86e81c5 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -120,8 +120,6 @@ int main(int argc, char **argv)
>   #include "qom/object_interfaces.h"
>   #include "qapi-event.h"
>
> -#define DEFAULT_RAM_SIZE 128
> -
>   #define MAX_VIRTIO_CONSOLES 1
>   #define MAX_SCLP_CONSOLES 1
>
> @@ -1306,7 +1304,11 @@ void hmp_usb_del(Monitor *mon, const QDict *qdict)
>
>   MachineState *current_machine;
>
> -static void machine_class_init(ObjectClass *oc, void *data)
> +/*
> + * Transitional class registration/init used for converting from
> + * legacy QEMUMachine to MachineClass.
> + */
> +static void qemu_machine_class_init(ObjectClass *oc, void *data)
>   {
>       MachineClass *mc = MACHINE_CLASS(oc);
>       QEMUMachine *qm = data;
> @@ -1344,7 +1346,7 @@ int qemu_register_machine(QEMUMachine *m)
>       TypeInfo ti = {
>           .name       = name,
>           .parent     = TYPE_MACHINE,
> -        .class_init = machine_class_init,
> +        .class_init = qemu_machine_class_init,
>           .class_data = (void *)m,
>       };
>
> @@ -2641,13 +2643,13 @@ out:
>       return 0;
>   }
>
> -static void set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size)
> +static void set_memory_options(uint64_t *ram_slots, ram_addr_t *maxram_size,
> +                               MachineClass *mc)
>   {
>       uint64_t sz;
>       const char *mem_str;
>       const char *maxmem_str, *slots_str;
> -    const ram_addr_t default_ram_size = (ram_addr_t)DEFAULT_RAM_SIZE *
> -                                        1024 * 1024;
> +    const ram_addr_t default_ram_size = mc->default_ram_size;
>       QemuOpts *opts = qemu_find_opts_singleton("memory");
>
>       sz = 0;
> @@ -3763,7 +3765,13 @@ int main(int argc, char **argv, char **envp)
>           machine_class = machine_parse(optarg);
>       }
>
> -    set_memory_options(&ram_slots, &maxram_size);
> +    if (machine_class == NULL) {
> +        fprintf(stderr, "No machine specified, and there is no default.\n"
> +                "Use -machine help to list supported machines!\n");
> +        exit(1);
> +    }
> +
> +    set_memory_options(&ram_slots, &maxram_size, machine_class);
You could directly pass default_ram_size instead of machine_class
to set_memory_options, but this is not enough to justify
a new version by itself. (You may consider it if you prepare another version)

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

Thanks,
Marcel

>
>       loc_set_none();
>
> @@ -3792,12 +3800,6 @@ int main(int argc, char **argv, char **envp)
>       }
>   #endif
>
> -    if (machine_class == NULL) {
> -        fprintf(stderr, "No machine specified, and there is no default.\n"
> -                "Use -machine help to list supported machines!\n");
> -        exit(1);
> -    }
> -
>       current_machine = MACHINE(object_new(object_class_get_name(
>                             OBJECT_CLASS(machine_class))));
>       if (machine_help_func(qemu_get_machine_opts(), current_machine)) {
>