Re: [patch] i386: use C code for current_thread_info()

[Avi Kivity]

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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