Re: [Qemu-devel] [PATCH v7 3/6] s390x/cpu: Move some CPU initialization into realize

[David Hildenbrand <dahi@linux.vnet.ibm.com>]

> In preparation for hotplug, defer some CPU initialization
> until the device is actually being realized.
> 
> Signed-off-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com>
> Reviewed-by: Andreas Färber <afaerber@suse.de>
> ---
>  target-s390x/cpu.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/target-s390x/cpu.c b/target-s390x/cpu.c
> index 603c2a1..8dfd063 100644
> --- a/target-s390x/cpu.c
> +++ b/target-s390x/cpu.c
> @@ -195,7 +195,13 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
>  {
>      CPUState *cs = CPU(dev);
>      S390CPUClass *scc = S390_CPU_GET_CLASS(dev);
> +    S390CPU *cpu = S390_CPU(dev);
> +    CPUS390XState *env = &cpu->env;
> 
> +#if !defined(CONFIG_USER_ONLY)
> +    qemu_register_reset(s390_cpu_machine_reset_cb, cpu);
> +#endif
> +    env->cpu_num = cs->cpu_index;
>      s390_cpu_gdb_init(cs);
>      qemu_init_vcpu(cs);
>  #if !defined(CONFIG_USER_ONLY)
> @@ -213,7 +219,6 @@ static void s390_cpu_initfn(Object *obj)
>      S390CPU *cpu = S390_CPU(obj);
>      CPUS390XState *env = &cpu->env;
>      static bool inited;
> -    static int cpu_num = 0;
>  #if !defined(CONFIG_USER_ONLY)
>      struct tm tm;
>  #endif
> @@ -223,7 +228,6 @@ static void s390_cpu_initfn(Object *obj)
>      cs->exception_index = EXCP_HLT;
>      cpu_exec_init(cs, &error_abort);
>  #if !defined(CONFIG_USER_ONLY)
> -    qemu_register_reset(s390_cpu_machine_reset_cb, cpu);
>      qemu_get_timedate(&tm, 0);
>      env->tod_offset = TOD_UNIX_EPOCH +
>                        (time2tod(mktimegm(&tm)) * 1000000000ULL);
> @@ -232,7 +236,6 @@ static void s390_cpu_initfn(Object *obj)
>      env->cpu_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, s390x_cpu_timer, cpu);
>      s390_cpu_set_state(CPU_STATE_STOPPED, cpu);
>  #endif
> -    env->cpu_num = cpu_num++;
> 
>      if (tcg_enabled() && !inited) {
>          inited = true;

Hmm, two things

a) env is not needed in this patch
b) This patch breaks cpu creation temporarily (cpu number rework). cpu_num is
always 0 - a problem at east for tcg.

You should introduce scc->next_cpu_id in this patch, cpu->id can be left
in the error handling patch.

David