Stuart Henderson <[email protected]> writes:

> Thanks for testing.
>
> On 2022/02/02 13:51, Dave Voutila wrote:
>>
>> Jason McIntyre <[email protected]> writes:
>>
>> > On Wed, Feb 02, 2022 at 04:52:40PM +0000, Stuart Henderson wrote:
>> >> This definitely wants testing on Ryzen ThinkPads (e.g. 
>> >> E485/E585/X395/T495s)
>> >> or Inspiron 5505, I see user TSC disabled on a lot of those in dmesglog.
>> >>
>> >>
>> >
>> > hi.
>> >
>> > here are the results from a 5505. was the timecounter meant to switch
>> > from tsc?
>> >
>> > jmc
>> >
>> > $ sysctl kern.timecounter
>> > kern.timecounter.tick=1
>> > kern.timecounter.timestepwarnings=0
>> > kern.timecounter.hardware=i8254
>> > kern.timecounter.choice=i8254(0) tsc(-1000) acpihpet0(1000) 
>> > acpitimer0(1000)
>> >
>>
>> I'm seeing the same issue...switching to i8254 pit where before it was
>> using tsc. :(
>
> There are two separate related things, one is the kernel choice, and the
> other is whether TSC can be used directly from userland for gettimeofday
> and friends without a syscall. Does the dmesg without the diff say "user
> TSC disabled"? If so then it was only using it in the kernel.
>

Yup. I believe this Ryzen laptop has always had userland TSC disabled. I
typically see:

  cpu6: disabling user TSC (skew=-105)

-dv

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