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Re: use of MI "pcu" code for x86 FPU, allocate FPU context dynamically

Le 10/09/2013 09:54, Jean-Yves Migeon a écrit :
I have two questions regarding dynfpustate:
1 - first, is it safe to have a sleepable allocation right into
fputrap(), especially in case of memory pressure?
2 - following 1), why not kmem_alloc the pcb FPU within cpu_attach?
There are already allocations that happen there (in particular:
reserved pages for MMU), memory pressure is low at this time (during
boot, and a hotplugged CPU would not be usable until cpu_attach
return, no risk of having a working CPU but without FPU state
tracking). IMO it would make sense to do it there. The FPU is not
expected to change dynamically.

Forget about point 2) for now, stupid error on my part

Jean-Yves Migeon

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