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Date: Fri, 5 Jun 2015 16:12:59 +0200
From: Richard Cochran <richardcochran@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>, Ingo Molnar <mingo@kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Prarit Bhargava <prarit@redhat.com>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Jan Kara <jack@suse.cz>, Jiri Bohac <jbohac@suse.cz>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        Shuah Khan <shuahkh@osg.samsung.com>
Subject: Re: [RFC][PATCH 4/4] time: Do leapsecond adjustment in gettime
 fastpaths
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On Fri, Jun 05, 2015 at 11:10:08AM +0200, Peter Zijlstra wrote:
> Firstly I would strongly suggest such applications not use UTC because
> of this, I think TAI was invented for just this reason.

So I wonder whether the bug in the original post affects TAI timers as
well...

> Secondly, how would John's patches help with this? Usespace loops
> reading time would be using the VDSO and would still not get the right
> time, and timers would be subject to the same IRQ latency that a hrtimer
> based leap second insert would, and would still very much not be in-sync
> across the cluster.

But we have a tick based insertion.  (IIRC, it used to be hrtimer
based, but that was buggy, too).

Thanks,
Richard