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SubjectRe: typo in scsi_obsolete.c

On Sun, 29 Nov 1998, Gerard Roudier wrote:

> The formula time_after(jiffies, least_reset + MIN_RESET_PERIOD) looks
> like very poor semantic to me. I donnot even want to ever burn a
> single neuron to understand it.

time_before(x,y) means: 'is x before y?'.
time_after(x,y) means: 'is x after y?'.

where both values are 'time' represented as signed integers.

> I may want to understand something that looks like the following:
> is_in_the_future(u_long time_stamp_in_the_past, u_long delay)

you can always add integers to time. The only thing that has to be wrapped
is comparison. Thus:

x+d means: 'd units after x'
x-d means: 'd units before x'

the whole concept is that we are representing a 'time ring' via signed
integers, but integer comparison in C is not type safe, so we have to wrap
it.

-- mingo


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