linux-kernel - Re: time: Improve documentation of timekeeeping

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Message-ID: <82mxcijtaz.fsf@gmail.com>
Date:	Sun, 30 Oct 2011 17:14:12 +0000
From:	Andy Moreton <andrewjmoreton@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: Re: time: Improve documentation of timekeeeping_adjust()

On Fri 28 Oct 2011, John Stultz wrote:

> On Fri, 2011-10-28 at 08:05 +0200, Richard Cochran wrote:
>> On Thu, Oct 27, 2011 at 06:12:42PM -0700, John Stultz wrote:
>> > diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
>> > index a5846a8..de8737e 100644
>> > --- a/kernel/time/timekeeping.c
>> > +++ b/kernel/time/timekeeping.c
>> > @@ -802,14 +802,44 @@ static void timekeeping_adjust(s64 offset)
>> >  	s64 error, interval = timekeeper.cycle_interval;
>> >  	int adj;
>> >  
>> > +	/*
>> > +	 * The point of this is to check if the error is greater then half
>> > +	 * an interval.
>> > +	 *
>> > +	 * First we shift it down from NTP_SHIFT to clocksource->shifted nsecs.
>> > +	 *
>> > +	 * Note we subtract one in the shift, so that error is really error*2.
>> > +	 * This "saves" dividing(shifting) intererval twice, but keeps the
>> > +	 * (error > interval) comparision as still measuring if error is
>> > +	 * larger then half an interval.
>> > +	 *
>> > +	 * Note: It does not "save" on aggrivation when reading the code.
>> 
>> ... or on "aggravation" either :)
>
> Sigh. I do need to start using an editor with built in spell checking.
> I'm so poor of a speller (and a typist) its really amazing its not
> worse.
>
> Thanks for catching that.
> -john

s/intererval/interval/

    AndyM

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