lkml.org 
[lkml]   [2017]   [Oct]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: Extreme time jitter with suspend/resume cycles
On Thu, Oct 5, 2017 at 2:04 PM, Thomas Gleixner <tglx@linutronix.de> wrote:
>> > So that clocksource driver looks correct. Do you have an idea in which
>> > context this time jump happens? Does it happen when you exercise your high
>> > frequency suspend/resume dance or is that happening just when you let the
>> > machine run forever as well?
>>
>> We couldn't devise any reproduction steps. We observed it happening at
>> unexpected times in a fleet of devices -- and we couldn't find any
>> patterns to clue us in.
>
> Ok. Did you talk to NXP about that? Or did you try to exercise reads in a
> loop to detect the wreckage and maybe a pattern in there?

Yes, we talked to NXP about it. They don't have a conclusion on what happened.
While they've been very helpful... we were off the path from their reference
implementation and so it's not a high priority for them.

No, we didn't try that because we prioritized the "persistent clock" approach.
I have a little more time now and can try the loop-reading strategy.

-gabe

\
 
 \ /
  Last update: 2017-10-05 23:15    [W:0.454 / U:0.072 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site