Re: [PATCH] task_struct colouring ...

["H. Peter Anvin" <hpa@zytor.com>]

Followup to:  <Pine.LNX.4.40.0111301614000.1600-100000@blue1.dev.mcafeelabs.com>
By author:    Davide Libenzi <davidel@xmailserver.org>
In newsgroup: linux.dev.kernel
> 
> The point is why store kernel pointers in global registers when You can
> achieve the same functionality, with a smaller patch, that does not need
> to be recoded for each CPU, without using global registers.
> 

Because global registers are faster!  This is exactly the kind of
stuff that is properly CPU-dependent and should be treated as such.
Heck, it even depends on what kind of multiprocessor architecture, if
any, you're using!

That being said, I belive that on most, if not all, processors, the
idea of having the pointer point not to "current" but to a per-CPU
memory area is *very* appealing, and a change that should be made
uniform unless it's a significant lose on some machines...

	-hpa
-- 
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