Re: x86-tip tsc/tick gripage

From: Mike Galbraith
Date: Wed Apr 26 2017 - 08:31:07 EST


On Wed, 2017-04-26 at 13:39 +0200, Mike Galbraith wrote:
> On Wed, 2017-04-26 at 12:26 +0200, Peter Zijlstra wrote:
> > On Wed, Apr 26, 2017 at 10:57:42AM +0200, Mike Galbraith wrote:
> >
> > > Both still lose their TSC.
> > >
> > > [ 11.982468] tsc: Refined TSC clocksource calibration: 2260.999 MHz
> > > [ 11.994275] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x20974a4d8bb, max_idle_ns: 440795246623 ns
> > > [ 13.064172] clocksource: Switched to clocksource tsc
> > > [ 240.247851] clocksource: timekeeping watchdog on CPU23: Marking clocksource 'tsc' as unstable because the skew is too large:
> > > [ 240.462501] clocksource: 'tsc' cs_now: 108fe5be09f cs_last: b90a6a0676 mask: ffffffffffffffff
> > > [ 240.675057] tsc: Marking TSC unstable due to clocksource watchdog
> >
> >
> > And they didn't use to? We don't typically write to TSC or TSC_ADJUST
> > and thus would not cause such behaviour.
>
> Nope.

DL980 seems perfectly happy with master.today.. so off we go.