Re: [Qemu-devel] [PATCH 19/21] add hot_add_cpu hook to QEMUMachine and export machine_args

[Andreas Färber]

Am 23.04.2013 10:29, schrieb Igor Mammedov:
> hot_add_cpu hook should be overriden by target that implements
> cpu hot-add via cpu-add QMP command.
> 
> Make machine_args available to machine init code, it allows
> to centralize cpu_model starage instead of adding target
> specific globals to keep it.
> 
> Signed-off-by: Igor Mammedov <address@hidden>
> ---
>  include/hw/boards.h |    3 +++
>  vl.c                |    6 +++++-
>  2 files changed, 8 insertions(+), 1 deletions(-)
> 
> diff --git a/include/hw/boards.h b/include/hw/boards.h
> index 425bdc7..de8f92a 100644
> --- a/include/hw/boards.h
> +++ b/include/hw/boards.h
> @@ -18,6 +18,8 @@ typedef struct QEMUMachineInitArgs {
>      const char *cpu_model;
>  } QEMUMachineInitArgs;
>  
> +extern QEMUMachineInitArgs *machine_args;
> +
>  typedef void QEMUMachineInitFunc(QEMUMachineInitArgs *args);
>  
>  typedef void QEMUMachineResetFunc(void);
> @@ -43,6 +45,7 @@ typedef struct QEMUMachine {
>      GlobalProperty *compat_props;
>      struct QEMUMachine *next;
>      const char *hw_version;
> +    void (*hot_add_cpu)(const int64_t id, Error **errp);
>  } QEMUMachine;
>  
>  int qemu_register_machine(QEMUMachine *m);
> diff --git a/vl.c b/vl.c
> index 5612c33..6a612e6 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -179,6 +179,8 @@ int main(int argc, char **argv)
>  #define MAX_VIRTIO_CONSOLES 1
>  #define MAX_SCLP_CONSOLES 1
>  
> +QEMUMachineInitArgs *machine_args;
> +
>  static const char *data_dir[16];
>  static int data_dir_idx;
>  const char *bios_name = NULL;
> @@ -4295,13 +4297,15 @@ int main(int argc, char **argv, char **envp)
>                                   .kernel_cmdline = kernel_cmdline,
>                                   .initrd_filename = initrd_filename,
>                                   .cpu_model = cpu_model };
> +    machine_args = &args;

args is a stack variable, so making it global does not strike me as a
good idea... (I did have a patch to split main() in two at one time)

> +    current_machine = machine;
> +
>      machine->init(&args);
>  
>      cpu_synchronize_all_post_init();
>  
>      set_numa_modes();
>  
> -    current_machine = machine;

Did you look up why it was placed here? Eduardo?
I'm not strongly opinionated but I wonder whether we may want to leave
it after machine->init?

Andreas

>  
>      /* init USB devices */
>      if (usb_enabled(false)) {
> 


-- 
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer; HRB 16746 AG Nürnberg