From: Thomas Gleixner <tglx@linutronix.de>
To: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>,
linux-kernel@vger.kernel.org,
John Stultz <john.stultz@linaro.org>,
Prarit Bhargava <prarit@redhat.com>
Subject: Re: [PATCH] rtc: adapt allowed RTC update error
Date: Wed, 02 Dec 2020 19:36:47 +0100 [thread overview]
Message-ID: <87eek8dphc.fsf@nanos.tec.linutronix.de> (raw)
In-Reply-To: <20201202153656.GC2231584@localhost>
On Wed, Dec 02 2020 at 16:36, Miroslav Lichvar wrote:
> On Wed, Dec 02, 2020 at 04:07:28PM +0100, Miroslav Lichvar wrote:
>> On Wed, Dec 02, 2020 at 02:44:53PM +0100, Thomas Gleixner wrote:
>> > Something like the completely untested below should make this reliable
>> > and only needs to retry when the work is running late (busy machine),
>> > but the wakeup will be on time or at max 1 jiffie off when high
>> > resolution timers are not available or disabled.
>>
>> It seems to work nicely. In my test most of the updates succeeded on
>> the first attempt hitting the right tick, the rest succeeding on the
>> second attempt. Only when the clock was set to run 10% faster, it
>> needed few more attempts to converge to the target time.
>
> I noticed an observable change wrt adjtimex() calls though. It seems
> it now reschedules the RTC update, i.e. there can be more than one
> update per 11 minutes. Was this intended?
No. Let me fix that.
Thanks,
tglx
next prev parent reply other threads:[~2020-12-02 18:37 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-01 14:38 [PATCH] rtc: adapt allowed RTC update error Miroslav Lichvar
2020-12-01 16:12 ` Jason Gunthorpe
2020-12-01 17:14 ` Miroslav Lichvar
2020-12-01 17:35 ` Jason Gunthorpe
2020-12-02 10:01 ` [PATCHv2] " Miroslav Lichvar
2020-12-02 13:44 ` [PATCH] " Thomas Gleixner
2020-12-02 15:07 ` Miroslav Lichvar
2020-12-02 15:36 ` Miroslav Lichvar
2020-12-02 18:36 ` Thomas Gleixner [this message]
2020-12-02 16:27 ` Jason Gunthorpe
2020-12-02 19:21 ` Thomas Gleixner
2020-12-02 20:54 ` Jason Gunthorpe
2020-12-02 22:08 ` Thomas Gleixner
2020-12-02 23:03 ` Jason Gunthorpe
2020-12-03 1:14 ` Thomas Gleixner
2020-12-03 2:04 ` Jason Gunthorpe
2020-12-03 2:10 ` Alexandre Belloni
2020-12-03 15:39 ` Thomas Gleixner
2020-12-03 16:16 ` Jason Gunthorpe
2020-12-03 21:05 ` Thomas Gleixner
2020-12-03 21:31 ` Thomas Gleixner
2020-12-03 22:36 ` Jason Gunthorpe
2020-12-04 13:02 ` Thomas Gleixner
2020-12-04 14:08 ` Jason Gunthorpe
2020-12-04 14:37 ` Alexandre Belloni
2020-12-04 14:46 ` Jason Gunthorpe
2020-12-04 15:08 ` Alexandre Belloni
2020-12-04 15:57 ` Jason Gunthorpe
2020-12-04 16:35 ` Alexandre Belloni
2020-12-03 22:00 ` Alexandre Belloni
2020-12-04 9:34 ` Thomas Gleixner
2020-12-04 9:51 ` Alexandre Belloni
2020-12-04 10:44 ` Thomas Gleixner
2020-12-03 17:29 ` Alexandre Belloni
2020-12-03 19:52 ` Thomas Gleixner
2020-12-03 15:52 ` Jason Gunthorpe
2020-12-03 16:07 ` Alexandre Belloni
2020-12-03 20:10 ` Jason Gunthorpe
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