[PATCH] irqchip/gic: Use GIC_SPI symbolic constant

Marc Zyngier marc.zyngier at arm.com
Sun Jul 16 14:08:01 PDT 2017


On Sun, Jul 16 2017 at 10:50:17 pm BST, Mason <slash.tmp at free.fr> wrote:
> On 16/07/2017 22:13, Marc Zyngier wrote:
>
>> Mason wrote:
>> 
>>> Use GIC_SPI explicitly instead of an implicit 0.
>> 
>> What bug is this fixing? What benefit does this bring?
>
> The patch aims to replace an (implicit) literal constant
> with the corresponding symbolic macro. IMO, it makes the
> intent somewhat clearer, and, more importantly, grepping
> for said symbol now returns the respective file/line.
> (It took me a while to find the line.)
>
> Are you saying that changing the code at this point is
> not worth the trouble?

You're assuming that this GIC_SPI macro has anything to do with the GIC
driver. It doesn't. That's just a convenience macro for people writing
DT, and definitely not something I'd ever want to rely on in the Linux
driver. The binding defines the raw value, and not this macro.

So to sum it up, thank you, but no thank out.

>
>>> FWIW, 'make C=2' flagged a few lines:
>>>
>>> $ make C=2 drivers/irqchip/irq-gic.o
>>>   CHECK   drivers/irqchip/irq-gic.c
>>> drivers/irqchip/irq-gic.c:1079:44: warning: incorrect type in
>>> assignment (different address spaces)
>>> drivers/irqchip/irq-gic.c:1079:44: expected void [noderef]
>>> <asn:3>*[noderef] <asn:2>*percpu_base
>>> drivers/irqchip/irq-gic.c:1079:44: got void [noderef]
>>> <asn:2>*[noderef] <asn:3>*<noident>
>> 
>> How is that related to this patch?
>
> I tested the patch with 'make C=2' and reported the
> output FWIW. Are you saying I should have written
> a separate message, or not bothered altogether?

An even better outcome would be analysing the issue and coming up with a
patch if there is something to fix. On its own, dumping these warnings
in the middle of something unrelated is a best at waste of bandwidth.

	M.
-- 
Jazz is not dead. It just smells funny.



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