Re: [PATCH v3 01/13] x86/retpoline: Add initial retpoline support

[Paolo Bonzini]

On 05/01/2018 11:28, Paul Turner wrote:
> 
> The "pause; jmp" sequence proved minutely faster than "lfence;jmp" which is why
> it was chosen.
> 
>   "pause; jmp" 33.231 cycles/call 9.517 ns/call
>   "lfence; jmp" 33.354 cycles/call 9.552 ns/call

Do you have timings for a non-retpolined indirect branch with the
predictor suppressed via IBRS=1?  So at least we can compute the break
even point.

Paolo