From mboxrd@z Thu Jan  1 00:00:00 1970
From: john stultz <johnstul@us.ibm.com>
Subject: Re: [PATCH] [RFC] timerfd: add TFD_NOTIFY_CLOCK_SET to watch for
 clock changes
Date: Wed, 01 Dec 2010 15:46:48 -0800
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Cc: Jamie Lokier <jamie@shareable.org>,
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To: Valdis.Kletnieks@vt.edu
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On Wed, 2010-12-01 at 17:46 -0500, Valdis.Kletnieks@vt.edu wrote:
> On Wed, 01 Dec 2010 10:43:59 GMT, Jamie Lokier said:
> 
> > So maybe CLOCK_MONOTONIC should be changed to include elapsed time
> > during suspend/resume, and CLOCK_MONOTONIC_RAW could remain as it is,
> > for programs that want that?
> 
> Wouldn't that be an API break for programs that are expecting the current
> behavior of CLOCK_MONOTONIC?  Yes, there should be a way to request either of
> them - but if there's only one way now, it should continue to act the current
> way, and the added way is the second option.

We do keep track of the amount of time in suspend (total_sleep_time), so
creating a new clockid to provide CLOCK_MONOTONIC + total_sleep_time
wouldn't be hard. We just haven't had a clear articulation of why it
would be useful to expose to userland (nor a clear name to describe
exactly what it represents).

thanks
-john