Subject: Re: [PATCH V2] xen-evtchn: Bind dyn evtchn:qemu-dm interrupt to next
 online VCPU
To: Anoob Soman <anoob.soman@citrix.com>, xen-devel@lists.xenproject.org,
        linux-kernel@vger.kernel.org
References: <1496746648-25300-1-git-send-email-anoob.soman@citrix.com>
Cc: jgross@suse.com
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Message-ID: <91bfac47-7258-cec0-2a61-29f2b2e5454b@oracle.com>
Date: Tue, 6 Jun 2017 15:41:34 -0400
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>  
>  /* Rebind an evtchn so that it gets delivered to a specific cpu */
> -static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
> +int xen_rebind_evtchn_to_cpu(int evtchn, unsigned tcpu)
>  {
>  	struct evtchn_bind_vcpu bind_vcpu;
> -	int evtchn = evtchn_from_irq(irq);
>  	int masked;
>  
>  	if (!VALID_EVTCHN(evtchn))
> @@ -1338,6 +1337,12 @@ static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
>  
>  	return 0;
>  }
> +EXPORT_SYMBOL_GPL(xen_rebind_evtchn_to_cpu);
> +
> +static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
> +{
> +	return xen_rebind_evtchn_to_cpu(evtchn_from_irq(irq), tcpu);
> +}

There is a single call site for rebind_irq_to_cpu() so why not call
xen_rebind_evtchn_to_cpu() directly?


>  
> +static void evtchn_bind_interdom_next_vcpu(int evtchn)
> +{
> +	static DEFINE_PER_CPU(int, bind_last_selected_cpu);
> +	unsigned int selected_cpu, irq;
> +	struct irq_desc *desc;
> +	unsigned long flags;
> +
> +	irq = irq_from_evtchn(evtchn);
> +	desc = irq_to_desc(irq);
> +
> +	if (!desc)
> +		return;
> +
> +	raw_spin_lock_irqsave(&desc->lock, flags);

Is there a reason why you are using raw_ version?

(Sorry, I should have noticed both of these earlier)

-boris