Re: [RFC PATCH v2 09/14] m68k: hp300: Remove hp300_gettimeoffset()

From: Finn Thain
Date: Sat Nov 24 2018 - 22:30:00 EST


On Sun, 25 Nov 2018, Michael Schmitz wrote:

> > We can benchmark gettimeofday syscalls on elgar but is that hardware
> > representative of other relevant models?
>
> I suppose the CIA is on the main board, so running with the slower clock
> speed that you'd see with a vanilla Amiga without 060 accelerator board.
> Ought to be representative enough?
>

Not really. An accelerated CPU clock exaggerates the slowdown factor,
given the fixed 0.7 MHz CIA clock.

The "(ticks > jiffy_ticks / 2)" conditional won't make anything worse even
if interrupt latency is already too high, so I'm inclined towards the more
prudent option. This patch series is already complicated enough.

In anycase, I'd prefer not to speculate about interrupt priorities or
latencies when the list probably has people who know the answers.

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