Re: [PATCH v2 09/19] crypto: x86 - use common macro for FPU limit

[Jason A. Donenfeld]

On Thu, Oct 13, 2022 at 3:48 PM Elliott, Robert (Servers)
<elliott@xxxxxxx> wrote:
> Perhaps we should declare a time goal like "30 us," measure the actual
> speed of each algorithm with a tcrypt speed test, and calculate the
> nominal value assuming some slow x86 CPU core speed?

Sure, pick something reasonable with good margin for a reasonable CPU.
It doesn't have to be perfect, but just vaguely right for supported
hardware.

> That could be further adjusted at run-time based on the supposed
> minimum CPU frequency (e.g., as reported in
> /sys/devices/system/cpu/cpufreq/policy0/scaling_min_freq).

Oh no, please no. Not another runtime knob. That also will make the
loop less efficient.