Re: xen: PV on HVM: support PV spinlocks

[Jeremy Fitzhardinge <jeremy@goop.org>]

 On 08/13/2010 12:06 PM, Stefano Stabellini wrote:
> xen: PV on HVM: support PV spinlocks
>
> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
>
> diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
> index 6f53453..5643c43 100644
> --- a/arch/x86/xen/enlighten.c
> +++ b/arch/x86/xen/enlighten.c
> @@ -1290,6 +1290,8 @@ static int __cpuinit xen_hvm_cpu_notify(struct notifier_block *self,
>  	switch (action) {
>  	case CPU_UP_PREPARE:
>  		per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
> +		if (xen_have_vector_callback)
> +			xen_init_lock_cpu(cpu);

Why does this depend on vector_callback?  pv spinlocks never have events
actually delivered.

Nice and simple otherwise.

    J

>  		break;
>  	default:
>  		break;
> @@ -1301,6 +1303,20 @@ static struct notifier_block __cpuinitdata xen_hvm_cpu_notifier = {
>  	.notifier_call	= xen_hvm_cpu_notify,
>  };
>  
> +static void xen_hvm_spinlock_init(void)
> +{
> +	if (!xen_have_vector_callback)
> +		return
> +	xen_init_lock_cpu(0);
> +	xen_init_spinlocks();
> +}
> +
> +static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
> +{
> +	xen_hvm_spinlock_init();
> +	native_smp_prepare_cpus(max_cpus);
> +}
> +
>  static void __init xen_hvm_guest_init(void)
>  {
>  	int r;
> @@ -1320,6 +1336,7 @@ static void __init xen_hvm_guest_init(void)
>  	x86_init.irqs.intr_init = xen_init_IRQ;
>  	xen_hvm_init_time_ops();
>  	xen_hvm_init_mmu_ops();
> +	smp_ops.smp_prepare_cpus = xen_hvm_smp_prepare_cpus;
>  }
>  
>  static bool __init xen_hvm_platform(void)
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel
>