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Date: Wed, 22 Apr 2015 12:11:14 +0200
From: Richard Cochran <richardcochran@gmail.com>
To: Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [Y2038] [PATCH 04/11] posix timers:Introduce the 64bit methods
 with timespec64 type for k_clock structure
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On Wed, Apr 22, 2015 at 10:45:23AM +0200, Thomas Gleixner wrote:
> So we could save one translation step if we implement new syscalls
> which have a scalar nsec interface instead of the timespec/timeval
> cruft and let user space do the translation to whatever it wants.

+1

> I personally would welcome such an interface as it makes user space
> programming simpler. Just (re)arming a periodic nanosleep based on
> absolute expiry time is horrible stupid today:

Jup.

> Thoughts?

Current user space example: The linuxptp programs are doing ns64 to
timespec conversions to call into the kernel, which then does timespec
to ns64 to talk to the hardware.  I would bet that most (all?) use
cases are better served with 64 bit nanosecond system calls.

Thanks,
Richard