Re: [Qemu-devel] [PATCH 05/16] introduce CPU hot-plug notifier

[Gleb Natapov <gleb@redhat.com>]

On Tue, Apr 16, 2013 at 12:12:45AM +0200, Igor Mammedov wrote:
> hot-added CPU will be distributed to acpi_piix4 and rtc_cmos
> 
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
> Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
> ---
> v2:
>   * move notifier to qom/cpu.c and call it from CPUClass.realize() on hotplug
>   * remove get_firmware_id() since it belong to other patch
> ---
>  include/sysemu/sysemu.h |  3 +++
>  qom/cpu.c               | 12 ++++++++++++
>  2 files changed, 15 insertions(+)
> 
> diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h
> index 6578782..a8c3de1 100644
> --- a/include/sysemu/sysemu.h
> +++ b/include/sysemu/sysemu.h
> @@ -152,6 +152,9 @@ void do_pci_device_hot_remove(Monitor *mon, const QDict *qdict);
>  /* generic hotplug */
>  void drive_hot_add(Monitor *mon, const QDict *qdict);
>  
> +/* CPU hotplug */
> +void qemu_register_cpu_added_notifier(Notifier *notifier);
> +
>  /* pcie aer error injection */
>  void pcie_aer_inject_error_print(Monitor *mon, const QObject *data);
>  int do_pcie_aer_inject_error(Monitor *mon,
> diff --git a/qom/cpu.c b/qom/cpu.c
> index 40a4259..819986e 100644
> --- a/qom/cpu.c
> +++ b/qom/cpu.c
> @@ -21,6 +21,17 @@
>  #include "qom/cpu.h"
>  #include "qemu-common.h"
>  #include "sysemu/kvm.h"
> +#include "qemu/notify.h"
> +#include "sysemu/sysemu.h"
> +
> +/* CPU hot-plug notifiers */
> +static NotifierList cpu_added_notifiers =
> +    NOTIFIER_LIST_INITIALIZER(cpu_add_notifiers);
> +
> +void qemu_register_cpu_added_notifier(Notifier *notifier)
> +{
> +    notifier_list_add(&cpu_added_notifiers, notifier);
> +}
>  
>  void cpu_reset_interrupt(CPUState *cpu, int mask)
>  {
> @@ -61,6 +72,7 @@ static void cpu_common_realizefn(DeviceState *dev, Error **errp)
>      if (dev->hotplugged) {
>          cpu_synchronize_post_init(CPU(dev));
>          resume_vcpu(CPU(dev));
> +        notifier_list_notify(&cpu_added_notifiers, dev);
Why do it after vcpu is running? May be notifier want to do something
that should be done before vcpu is running.

>      }
>  }
>  
> -- 
> 1.8.2
> 
> 

--
			Gleb.