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SubjectRe: how does kernel get the "current" task struct?
Hi,

On Wed, 02 Feb 2000 18:12:12 -0800, Jun Sun <jsun@mvista.com> said:

> I suppose if you have a global pointer "current", you don't even need
> to do "andl" instruction. (But you will need to update "current"
> whenever a context switch happens, and you'll probably have a
> "current" array in the CMP version.)

That's the whole problem: on SMP, with a current table, you'd have to
lookup the number of the current CPU every time you wanted to access
"current". Doing the stack arithmetic trick is _much_ faster than using
the cpuid instruction.

--Stephen

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