From: Peter Zijlstra <peterz@infradead.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: John Stultz <john.stultz@linaro.org>,
lkml <linux-kernel@vger.kernel.org>,
Prarit Bhargava <prarit@redhat.com>,
Daniel Bristot de Oliveira <bristot@redhat.com>,
Richard Cochran <richardcochran@gmail.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
Date: Tue, 2 Jun 2015 11:21:19 +0200 [thread overview]
Message-ID: <20150602092119.GX19282@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <20150602090154.GA2590@gmail.com>
On Tue, Jun 02, 2015 at 11:01:54AM +0200, Ingo Molnar wrote:
> > Currently, leapsecond adjustments are done at tick time.
> >
> > As a result, the leapsecond was applied at the first timer
> > tick *after* the leapsecond (~1-10ms late depending on HZ),
> > rather then exactly on the second edge.
So why not program a hrtimer to expire at the exact right time? Then
even the VDSO gets its time 'right' and you avoid touching all the
fast paths.
next prev parent reply other threads:[~2015-06-02 9:21 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-29 20:24 [RFC][PATCH 0/4] Fixes for leapsecond expiring early ABS_TIME CLOCK_REALTIME timers John Stultz
2015-05-29 20:24 ` [RFC][PATCH 1/4] selftests: timers: Add leap-second timer edge testing to leap-a-day.c John Stultz
2015-05-29 20:24 ` [RFC][PATCH 2/4] timer_list: Add the base offset so remaining nsecs are accurate for non monotonic timers John Stultz
2015-05-29 20:24 ` [RFC][PATCH 3/4] ntp: Use printk_deferred in leapsecond path John Stultz
2015-06-02 10:31 ` Jiri Bohac
2015-06-02 10:43 ` Jiri Kosina
2015-06-02 16:14 ` John Stultz
2015-06-02 16:04 ` John Stultz
2015-05-29 20:24 ` [RFC][PATCH 4/4] time: Do leapsecond adjustment in gettime fastpaths John Stultz
2015-05-31 16:05 ` Richard Cochran
2015-06-02 9:01 ` Ingo Molnar
2015-06-02 9:21 ` Peter Zijlstra [this message]
2015-06-02 14:09 ` John Stultz
2015-06-02 15:52 ` John Stultz
2015-06-03 9:04 ` Ingo Molnar
2015-06-03 17:44 ` John Stultz
2015-06-04 6:48 ` Ingo Molnar
2015-06-05 0:08 ` John Stultz
2015-06-05 7:29 ` Peter Zijlstra
2015-06-05 9:04 ` Richard Cochran
2015-06-05 9:10 ` Peter Zijlstra
2015-06-05 14:12 ` Richard Cochran
2015-06-05 17:28 ` John Stultz
2015-06-06 9:44 ` Thomas Gleixner
2015-06-08 17:55 ` John Stultz
2015-06-08 19:05 ` Thomas Gleixner
2015-06-08 20:02 ` Thomas Gleixner
2015-06-05 11:37 ` Prarit Bhargava
2015-06-05 12:07 ` Thomas Gleixner
2015-06-05 14:22 ` Richard Cochran
2015-06-05 17:24 ` John Stultz
2015-05-31 13:55 ` [RFC][PATCH 0/4] Fixes for leapsecond expiring early ABS_TIME CLOCK_REALTIME timers Prarit Bhargava
2015-06-01 11:57 ` Prarit Bhargava
2015-06-01 17:02 ` John Stultz
2015-06-01 17:43 ` Prarit Bhargava
2015-06-01 20:18 ` Daniel Bristot de Oliveira
2015-06-01 20:32 ` John Stultz
2015-06-01 21:42 ` Prarit Bhargava
2015-06-01 22:29 ` Daniel Bristot de Oliveira
2015-06-02 6:19 ` John Stultz
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