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Date: Fri, 9 Sep 2016 15:47:54 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Josh Triplett <josh@joshtriplett.org>
cc: Richard Cochran <richardcochran@gmail.com>,
        John Stultz <john.stultz@linaro.org>, Nicolas Pitre <nico@fluxnic.net>,
        lkml <linux-kernel@vger.kernel.org>
Subject: Re: [RFC/PATCH] posix-timers: make them configurable
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On Fri, 9 Sep 2016, Josh Triplett wrote:

> On Fri, Sep 09, 2016 at 09:48:57AM +0200, Richard Cochran wrote:
> > On Thu, Sep 08, 2016 at 02:19:24PM -0700, John Stultz wrote:
> > > Also given many other syscalls take clockids and the backing logic
> > > isn't really getting removed (probably could cut the dynamic posix
> > > clocks core with the same conditional), I wonder if you could get a
> > > similar size win by taking a slightly more narrow cutting of the
> > > subsystem. That way you could preserve the more useful clock_gettime()
> > > functionality, but maybe stub out some of the less often used
> > > functionality.
> > 
> > I want to support tinification, but I also doubt the utility of
> > removing clock_gettime() and clock_nanosleep().  I can't imagine ever
> > building a user space without those.  In fact, thinking about IoT,
> > having good time is critical, and so these are the *last* functions I
> > would remove when downsizing.
> 
> 1) If you already have another function providing time and don't need two.

Agreed.

> 2) If you run an entirely event-driven loop and don't sleep.

I hope you wanted to say: and don't use *nanosleep() :) Otherwise you'd
have a full busy polling event loop which I doubt is desirable ...

Thanks,

	tglx