RE: [PATCH] staging: wfx: make a const array static, makes object smaller

[David Laight]

From: Joe Perches
> Sent: 17 October 2020 01:12
> 
> On Fri, 2020-10-16 at 23:33 +0100, Colin King wrote:
> > From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> >
> > Don't populate const array filter_ies on the stack but instead
> > make it static. Makes the object code smaller by 261 bytes.
> >
> > Before:
> >    text	   data	    bss	    dec	    hex	filename
> >   21674	   3166	    448	  25288	   62c8	drivers/staging/wfx/sta.o
> >
> > After:
> >    text	   data	    bss	    dec	    hex	filename
> >   21349	   3230	    448	  25027	   61c3	drivers/staging/wfx/sta.o
> 
> Thanks.
> 
> It's odd to me it's so large a change as it's only
> 24 bytes of initialization. (3 entries, each 8 bytes)

Perhaps the 'stack protector' crap?

Interestingly, loading the data from the 'readonly' section
is probably a data cache miss.
Which might end up being slower than the extra code to
update the on-stack data.
The extra code might get prefetched...

	David
 

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