Re: [RFC 1/6] Framework

[Andi Kleen]

> >With local_t you don't need to turn off interrupts
> >anymore.
> >
> 
> Then you can't use __local_xxx, and so many architectures will use
> atomic instructions (the ones who don't are the ones with tripled
> cacheline footprint of this structure).

They are wrong then. atomic instructions is the wrong implementation
and they would be better off with asm-generic. 

If anything they should use per_cpu counters for interrupts and 
use seq locks. Or just turn off the interrupts for a short time
in the low level code.

> 
> Sure i386 and x86-64 are happy, but this would probably slow down
> most other architectures.

I think it is better to fix the other architectures then - if they
are really using a full scale bus lock for this they're just wrong.

I don't think it is a good idea to do a large change in generic
code just for dumb low level code.

-Andi
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