Re: cpu-2.5.64-1

William Lee Irwin III (wli@holomorphy.com)
Sun, 16 Mar 2003 04:00:57 -0800


On Sun, 16 Mar 2003 03:32:54 -0800, William Lee Irwin III wrote:
>> Another thought I had was wrapping things in structures for both small
>> and large, even UP systems so proper typechecking is enforced at all
>> times. That would probably need a great deal of arch sweeping to do,
>> especially as a number of arches are UP-only (non-SMP case's motive #2).

On Sun, Mar 16, 2003 at 10:53:19PM +1100, Keith Owens wrote:
> Keep the optimized model, where cpu_online_map is #defined to 1 for UP.
> Changing it to an ADT just to get type checking on architectures that
> only support UP looks like a bad tradeoff.

It shouldn't hurt UP:

typedef { unsigned long mask; } cpumask_t;

#define cpu_online_map ({ 1UL })

or some such nonsense with all the usual special cases. The arch code
impact OTOH can't really be gotten around with such tricks, if it's
significant. More food for thought...

-- wli
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