> ARM doesn't have an instruction for cpu_relax(), so it can't intercept > it. Given ppc's dislike of overcommit, and the way it implements > cpu_relax() by adjusting hw thread priority, I'm guessing it doesn't > intercept those either, but I'm copying the ppc people in case I'm > wrong. So it's s390 and x86.
No but our spinlocks call __spin_yield() (or __rw_yield) which does some paravirt tricks already. We check if the holder is currently running, and if not, we call the H_CONFER hypercall which can be used to "give" our time slice to the holder. Our implementation of H_CONFER in KVM is currently a nop though. Cheers, Ben. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
