Re: [PATCH 09/14] genirq: Implement irq_send_ipi() to be used by drivers

[Thomas Gleixner <tglx@linutronix.de>]

On Tue, 3 Nov 2015, Qais Yousef wrote:
> --- a/kernel/irq/manage.c
> +++ b/kernel/irq/manage.c
> @@ -2013,7 +2013,6 @@ EXPORT_SYMBOL_GPL(irq_set_irqchip_state);
>  struct ipi_mapping *irq_alloc_ipi_mapping(unsigned int nr_cpus)
>  {
>  	struct ipi_mapping *map;
> -	int i;

That one wants to be folded back into the patch which adds it.

> +
> +/**
> + *	__irq_desc_send_ipi - send an IPI to target CPU(s)
> + *	@irq_desc: pointer to irq_desc of the IRQ
> + *	@dest: dest CPU(s), must be the same or a subset of the mask passed to
> + *	       irq_reserve_ipi()
> + *
> + *	Sends an IPI to all cpus in dest mask.
> + *	This function is meant to be used from arch code to save the need to do
> + *	desc lookup that happens in the generic irq_send_ipi().
> + *
> + *	Returns zero on success and negative error number on failure.
> + */
> +int __irq_desc_send_ipi(struct irq_desc *desc, const struct ipi_mask *dest)
> +{
> +	struct irq_data *data = irq_desc_get_irq_data(desc);
> +	struct irq_chip *chip = irq_data_get_irq_chip(data);
> +
> +	if (!chip || !chip->irq_send_ipi)
> +		return -EINVAL;
> +
> +	if (dest->nbits > data->common->ipi_mask->nbits)
> +		return -EINVAL;
> +
> +	/*
> +	 * Do not validate the mask for IPIs marked global. These are
> +	 * regular IPIs so we can avoid the operation as their target
> +	 * mask is the cpu_possible_mask.
> +	 */
> +	if (!data->common->ipi_mask->global) {
> +		if (dest->global)
> +			return -EINVAL;
> +
> +		if (!bitmap_subset(dest->cpu_bitmap,
> +				   data->common->ipi_mask->cpu_bitmap,
> +				   dest->nbits))
> +			return -EINVAL;
> +	} else {
> +		if (!dest->global)
> +			return -EINVAL;

We might want to add sanity checks here as well, but you can leave it
as is for now.

This can move to ipi.c as well.

Thanks,

	tglx