Re: [PATCH 08/15] genirq: Add runtime power management support for IRQ chips

[Thomas Gleixner]

On Thu, 17 Mar 2016, Jon Hunter wrote:
>  /**
>   * struct irq_chip - hardware interrupt chip descriptor
>   *
> + * @parent:		pointer to associated device

That's really a bad name. parent suggests that this is a parent interrupt chip
and your explanation sucks as well. What's an associated device? Network card? 

>  #include <linux/irqdesc.h>
>  #include <linux/kernel_stat.h>
> +#include <linux/pm_runtime.h>
>  
>  #ifdef CONFIG_SPARSE_IRQ
>  # define IRQ_BITMAP_BITS	(NR_IRQS + 8196)
> diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
> index b2a93a37f772..65878e7c7c82 100644
> --- a/kernel/irq/manage.c
> +++ b/kernel/irq/manage.c
> @@ -1114,6 +1114,10 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
>  	if (!try_module_get(desc->owner))
>  		return -ENODEV;
>  
> +	ret = irq_chip_pm_get(&desc->irq_data);
> +	if (ret < 0)
> +		goto out_mput;

So this call nests inside the chip_bus_lock() region. Is that intentional?

Thanks,

	tglx