Re: [Qemu-devel] [PATCH v3 03/19] pc: extract CPU lookup into a separate function

[Eduardo Habkost]

On Wed, Jul 06, 2016 at 08:20:39AM +0200, Igor Mammedov wrote:
> it will be reused in the next patch at pre_plug time
> 
> Signed-off-by: Igor Mammedov <address@hidden>
> ---
> v2:
>   - rename pc_find_cpu() into pc_find_cpu_slot() and add comment to it
>      Eduardo Habkost <address@hidden>
> ---
>  hw/i386/pc.c | 29 ++++++++++++++++++++++-------
>  1 file changed, 22 insertions(+), 7 deletions(-)
> 
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index 7ab06c2..3c42d84 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -1675,11 +1675,30 @@ static int pc_apic_cmp(const void *a, const void *b)
>     return apic_a->arch_id - apic_b->arch_id;
>  }
>  
> +/* returns pointer to CPUArchId descriptor that matches CPU's apic_id
> + * in pcms->possible_cpus->cpus, if pcms->possible_cpus->cpus has no
> + * entry correponding to CPU's apic_id returns NULL.
> + */
> +static CPUArchId *pc_find_cpu_slot(PCMachineState *pcms, CPUState *cpu,
> +                                   int *idx)
> +{
> +    CPUClass *cc = CPU_GET_CLASS(cpu);
> +    CPUArchId apic_id, *found_cpu;
> +
> +    apic_id.arch_id = cc->get_arch_id(CPU(cpu));
> +    found_cpu = bsearch(&apic_id, pcms->possible_cpus->cpus,
> +        pcms->possible_cpus->len, sizeof(*pcms->possible_cpus->cpus),
> +        pc_apic_cmp);
> +    if (found_cpu && idx) {
> +        *idx = found_cpu - pcms->possible_cpus->cpus;

Do you have a use case for the idx parameter? I don't see it
being used for anything in this series.

> +    }
> +    return found_cpu;
> +}
> +
>  static void pc_cpu_plug(HotplugHandler *hotplug_dev,
>                          DeviceState *dev, Error **errp)
>  {
> -    CPUClass *cc = CPU_GET_CLASS(dev);
> -    CPUArchId apic_id, *found_cpu;
> +    CPUArchId *found_cpu;
>      HotplugHandlerClass *hhc;
>      Error *local_err = NULL;
>      PCMachineState *pcms = PC_MACHINE(hotplug_dev);
> @@ -1703,11 +1722,7 @@ static void pc_cpu_plug(HotplugHandler *hotplug_dev,
>      /* increment the number of CPUs */
>      rtc_set_memory(pcms->rtc, 0x5f, rtc_get_memory(pcms->rtc, 0x5f) + 1);
>  
> -    apic_id.arch_id = cc->get_arch_id(CPU(dev));
> -    found_cpu = bsearch(&apic_id, pcms->possible_cpus->cpus,
> -        pcms->possible_cpus->len, sizeof(*pcms->possible_cpus->cpus),
> -        pc_apic_cmp);
> -    assert(found_cpu);
> +    found_cpu = pc_find_cpu_slot(pcms, CPU(dev), NULL);
>      found_cpu->cpu = CPU(dev);
>  out:
>      error_propagate(errp, local_err);
> -- 
> 2.7.0
> 

-- 
Eduardo