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SubjectRe: [patch] i386: use C code for current_thread_info()
Andreas Mohr wrote:
>
> An entirely different way would be to store the stack base value in a
> global variable and update that on each context switch, but it would
> increase
> context switch overhead and have >= 2 cycles access time for L1 cache
> (which
> would be the best memory access case!), which would most likely be more
> combined overhead than an AGI stall (I was mistaken in declaring the
> stall
> a pipeline flush - it's only a stall for a couple cycles, not a full
> flush
> wasting ~ 15 cycles).
>

That wouldn't work on SMP. You'd need per-cpu variables, which are
likely even slower.

[One way around that would be to use a segment register for the per-cpu
areas]

--
error compiling committee.c: too many arguments to function

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