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Date: Mon, 30 Jan 2017 14:32:02 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: David Daney <ddaney@caviumnetworks.com>
cc: Marc Zyngier <marc.zyngier@arm.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linus Walleij <linus.walleij@linaro.org>
Subject: Re: irq domain hierarchy vs. chaining w/ PCI MSI-X...
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On Fri, 13 Jan 2017, David Daney wrote:
> At the point where the handle_*_irq() functions call handle_irq_event(), we
> need to 9optionally) do something both immediately before and after the call
> to handle_irq_event().
> 
> In irq_chip add a function:
> 
>     void (*irq_handle)(struct irq_data *data, struct irq_desc *desc);
> 
> Really this is the per irq_chip flow handler.
> 
> Then in handle_fasteoi_irq() and probably the other flow handlers as well:
> 
>    .
>    .
>    .
>    if (chip->irq_handle)
>       chip->irq_handle(&desc->irq_data, desc);
>    else
>       handle_irq_event(desc);
>    .
>    .
>    .
> 
> Those 4 lines of code could be factored out into a helper function in chip.c


And why don't you just write a flow handler function which does exactly
what you need instead of adding more conditionals into all hotpath
functions?

Thanks,

	tglx