Re: [Qemu-devel] [PATCH 7/7] Implement cpu hot-add using device_add monitor command

[Anthony Liguori]

On 02/15/2012 05:16 PM, Igor Mammedov wrote:
> Adds ability to hot-add cpus if guest was started with options
>      -smp X,maxcpus=Y
> where X<  Y.
> For simplicity sake this implementation doesn't allow to add specific
> cpu but rather it adds the next not yet plugged cpu.
>
> For adding cpu just execute following command in monitor:
>      device_add cpu-pc
> If guest was started with a specific cpu model, then add option model
> to cmonitor command. for example:
>      device_add cpu-pc,model="host"
>
> Signed-off-by: Igor Mammedov<address@hidden>

I don't see how the code matches this description, but unless you've got 
qdev-ification patches in the earlier ones (haven't made the list yet), 
device_add is not the right place for this.

There's no such thing as "cpu-pc" either.  You should start with a cpu_add 
command.

Regards,

Anthony Liguori

> ---
>   hw/pc.c |   11 +++++++++++
>   1 files changed, 11 insertions(+), 0 deletions(-)
>
> diff --git a/hw/pc.c b/hw/pc.c
> index ec50f16..5923549 100644
> --- a/hw/pc.c
> +++ b/hw/pc.c
> @@ -44,6 +44,8 @@
>   #include "ui/qemu-spice.h"
>   #include "memory.h"
>   #include "exec-memory.h"
> +#include "cpus.h"
> +#include "kvm.h"
>
>   /* output Bochs bios info messages */
>   //#define DEBUG_BIOS
> @@ -941,6 +943,10 @@ static int cpu_device_init(ICCBusDevice *dev)
>   #endif
>       }
>
> +    if (runstate_is_running()) {
> +        pause_all_vcpus();
> +    }
> +
>       if (cpu_x86_init_inplace(env, cpu->model)<  0) {
>           return -1;
>       }
> @@ -949,6 +955,11 @@ static int cpu_device_init(ICCBusDevice *dev)
>           env->apic_state = apic_init(env, env->cpuid_apic_id);
>       }
>
> +    cpu_synchronize_post_init(env);
> +    if (runstate_is_running()) {
> +        resume_all_vcpus();
> +        acpi_cpu_hot_plug(env->cpuid_apic_id, 1);
> +    }
>       return 0;
>   }