Hi,

I've been making changes for MIPS on the yamt-idlelwp branch and got stung
by the fact that there's no ci_curlwp pointer in struct cpu_info. That's
easy to solve, but I wonder if it's useful to store the value of curlwp in
gp or another register. That would allow defining curcpu as curlwp->l_cpu.

I think it's worthwhile doing since the new locking primitives want to know
what curlwp is quite often, and I've slowly been coming around to the idea
that passing "struct lwp *" about all over the place leads to confusion.

Thoughts?

Andrew