Messages in this thread | | | Subject | Re: [PATCH 15/17] KVM: retpolines: x86: eliminate retpoline from vmx.c exit handlers | From | Paolo Bonzini <> | Date | Wed, 25 Sep 2019 09:50:38 +0200 |
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On 24/09/19 23:46, Andrea Arcangeli wrote: >>> >>> I would keep only EXIT_REASON_MSR_WRITE, EXIT_REASON_PREEMPTION_TIMER, >>> EXIT_REASON_EPT_MISCONFIG and add EXIT_REASON_IO_INSTRUCTION. >> Intuition doesn't work great when it comes to CPU speculative >> execution runtime. I can however run additional benchmarks to verify >> your theory that keeping around frequent retpolines will still perform >> ok. > On one most recent CPU model there's no measurable difference with > your list or my list with a hrtimer workload (no cpuid). It's > challenging to measure any difference below 0.5%.
Let's keep the short list then.
Paolo
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