[dpdk-dev] [PATCH 0/5] remove usage of register keyword in C

[Stephen Hemminger]

On Wed, 1 Aug 2018 18:03:04 +0000
Yongseok Koh <yskoh at mellanox.com> wrote:

> > On Jul 31, 2018, at 11:07 AM, Stephen Hemminger <stephen at networkplumber.org> wrote:
> > 
> > On Tue, 31 Jul 2018 18:48:40 +0200
> > Adrien Mazarguil <adrien.mazarguil at 6wind.com> wrote:
> >   
> >> On Tue, Jul 31, 2018 at 09:30:54AM -0700, Stephen Hemminger wrote:  
> >>> Declaring variables as register in C is a leftover from an earlier
> >>> era (like cassette tape decks in cars).    
> >> 
> >> I don't agree here. It's a hint for compilers and developers that the
> >> address of such variables won't be needed (and cannot be taken) to enable
> >> whatever optimizations are possible knowing this.
> >> 
> >> Somewhat like inline functions, it's not a forced optimization, just a
> >> useful hint that shouldn't hurt if used wisely.
> >> 
> >> Besides, cassette decks are not dead yet :)  
> > 
> > If you look at the code, that is not how register is being used (ie. don't take
> > address of this). It seems like an attempt at optimization.  
> 
> I know compilers are smart enough and the occurrences in mlx4/5 were made from
> my old fashioned habit. But, I don't see any urgency to push this patch in RC
> stage even though I'm 99% sure that it is harmless. And in general I don't even
> understand why we can't live with that if it isn't harmful (or a violation) but
> informative. I mean no badness but at least one goodness :-)
> 
> Thanks,
> Yongseok
> 

Sure, this is intended for next release not rc stage.
Just trying to clean up code base where I see it.