Andrew Morton wrote:
>
> "David S. Miller" wrote:
> >
> > From: Andrew Morton <akpm@xxxxxxxxx>
> > Date: Sat, 07 Dec 2002 15:29:16 -0800
> >
> > Jeff Garzik wrote:
> > > Attached is cut #2. Thanks for all the near-instant feedback so far :)
> > > Andrew, does the attached still need padding on SMP?
> >
> > It needs padding _only_ on SMP. ____cacheline_aligned_in_smp.
> >
> > non-smp machines lack L2 caches? That's new to me :-)
> >
> > More seriously, there are real benefits on non-SMP systems.
>
> Then I am most confused. None of these fields will be put under
> busmastering or anything like that, so what advantage is there in
> spreading them out?
Oh I see what you want - to be able to pick up all the operating fields
in a single fetch.
That will increase the overall cache footprint though. I wonder if
it's really a net win, over just keeping it small.
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