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Date: Tue, 23 May 2017 15:02:05 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: David Laight <David.Laight@ACULAB.COM>
cc: Arnd Bergmann <arnd@arndb.de>, linux-s390 <linux-s390@vger.kernel.org>,
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        Christoph Hellwig <hch@lst.de>
Subject: RE: RFC: better timer interface
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On Tue, 23 May 2017, David Laight wrote:
> From: Thomas Gleixner
> > Sent: 23 May 2017 12:59
> > On Tue, 23 May 2017, David Laight wrote:
> > 
> > > From: Thomas Gleixner
> > > > Sent: 21 May 2017 19:15
> > > ...
> > > > > timer_start(timer, ms, abs)
> > > >
> > > > I'm not even sure, whether we need absolute timer wheel timers at
> > > > all, because most use cases are relative to now.
> > >
> > > Posix requires absolute timers for some userspace calls
> > > (annoying because the code often wants relative).
> > 
> > Posix is completely irrelevant here. These timers are purely kernel
> > internal.
> 
> Somehow pthread_cond_timedwait() has to be implemented.
> Doing so without kernel timers that use absolute 'wall clock' time is tricky.

Oh well. The timer wheel timers are NOT used to implement any posix
interface. That's all handled by hrtimers and they are not debated here.

So still nothing to see here.

Thanks,

	tglx