Re: v4.11-rc1 boot time regression

From: Andy Shevchenko
Date: Wed Mar 08 2017 - 11:21:18 EST


On Wed, Mar 8, 2017 at 10:26 AM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
> On Tue, 7 Mar 2017, Andy Shevchenko wrote:
>> On Tue, Mar 7, 2017 at 9:21 PM, Linus Torvalds
>> <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>> > On Tue, Mar 7, 2017 at 11:02 AM, Andy Shevchenko
>> > <andy.shevchenko@xxxxxxxxx> wrote:
>> >>
>> >> 60 seconds of wait for what exactly? I have no clue right now. Any suggestions?
>> >
>> > Ugh. If it is something that is actively sleeping, sysrq-t during the
>> > pause might give a hint.
>>
>> Unfortunately seems I can't do this. I managed to disable watchdog in
>> U-Boot, but seems console is not yet switched to the driver my blind
>> key presses went nowhere.
>>
>> > But it could be just a timer thing with nobody actively waiting for
>> > it, just a general init completion thing, and then it wouldn't show up
>> > as a thread with a backtrace. In that case you might need to bisect
>> > it..
>>
>> Looks like it's the only way if 60 seconds doesn't ring a bell to anyone...
>> Anyway, now (as you know :-) ) quite late in Hki, have to give my body
>> a bit of sleep.
>
> A shot in the dark:
>
> Could you try Linus head first, especially commit:
>
> fa3aa7a54fe6 ("jiffies: Revert bogus conversion of NSEC_PER_SEC to TICK_NSEC")
>
> which fixes: 93825f2ec736 ("jiffies: Reuse TICK_NSEC instead of NSEC_PER_JIFFY")

Thomas, you are cool! That is the one. Thanks!

--
With Best Regards,
Andy Shevchenko