Re: [PATCH 07/12] time: Try to catch clocksource delta underflows

From: Ingo Molnar
Date: Sat Mar 07 2015 - 04:34:49 EST



* John Stultz <john.stultz@xxxxxxxxxx> wrote:

> In the case where there is a broken clocksource
> where there are multiple actual clocks that
> aren't perfectly aligned, we may see small "negative"
> deltas when we subtract now from cycle_last.

So this is a typical example where putting argument references is
really helpful. Consider these two variants:

deltas when we subtract now from cycle_last.

deltas when we subtract 'now' from 'cycle_last'.

I had to read the first variant three times until I realized that
'now' is a C variable misleadingly inserted into English text.

> The values are actually negative with respect to the
> clocksource mask value, not necessarily negative
> if cast to a s64, but we can check by checking the
> delta see if it is a small (relative to the mask)
> negative value (again negative relative to the mask).

typo.

Thanks,

Ingo
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