Re: [PATCH net-next 01/14] etherdevice: Add eth_<foo>_addr CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS code

From: Joe Perches
Date: Tue Mar 03 2015 - 14:41:19 EST


On Tue, 2015-03-03 at 14:27 -0500, David Miller wrote:
> From: Joe Perches <joe@xxxxxxxxxxx>
> Date: Tue, 03 Mar 2015 11:07:51 -0800
> > On Tue, 2015-03-03 at 10:42 -0800, Eric Dumazet wrote:
> >> On Tue, 2015-03-03 at 10:25 -0800, Joe Perches wrote:
> >>
> >> > At least for arm gcc 4.6.3, it emits different code
> >> > for net/l2tp/l2tp_eth.o
> >>
> >> Then it looks like arm gcc or arm linux memset() should be improved.
> >
> > Perhaps you can take that up with the gcc folk.
> >
> > I think it appropriate to improve the actual emitted
> > code for the compiler I use.
>
> In the long term, this is poor time spent. If you fixed GCC
> everyone would benefit in the world, not just kernel builders.
>
> Furthermore, none of this crap is in the fast path of anything.
>
> I'm not applying this series, it's basis is not well founded
> yet you keep trying to argue otherwise.

Until such time as the linux crosstools compilers are updated,
(they seem stuck on 4.6.3 from 3 years ago)
https://www.kernel.org/pub/tools/crosstool/
I think the series is a trivial, small improvement.

I believe that's the only "argument" I've made.

Your choice to apply it or not, but if the series
isn't appropriate, likely the existence of both
eth_zero_addr and eth_broadcast_addr is suspect too.

cheers, Joe

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