Re: [PATCH][next] iio: adc: make read-only const array config static

[David Laight]

On Tue, 14 Jul 2026 20:08:10 +0300
Andy Shevchenko <andriy.shevchenko@xxxxxxxxx> wrote:

> On Tue, Jul 14, 2026 at 05:50:12PM +0100, Colin Ian King wrote:
> > Don't populate the read-only const array config on the stack at run
> > time, instead make it static.  
> 
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>
> 
> ...
> 
> In all patches like this it's always a bikeshedding possible of moving static
> data outside of a function. I have no strong opinion in these cases (when the
> data solely used by a single function), but in general it might give different
> readability experience (it's harder to notice static data in the local function
> definition block). So I leave this exercise to the maintainers of the respective
> pieces of the code.
> 

If global you start wondering where it is used....

There is also the fact that run-time initialisation of a 3 byte array
on stack is very likely to generate faster code than using static data.
Mostly because the access to the static data is likely to be a cache miss.

Then there are the architectures where just generating the address of
the static data takes multiple instructions.
In that case the on-stack version may even be smaller.

	David