Messages in this thread | | | Date | Wed, 9 Sep 2015 10:32:43 +0200 | From | Miroslav Lichvar <> | Subject | Re: [PATCH 2/2][RFC] kselftest: timers: Add adjtick test to validate adjtimex() tick adjustments |
| |
On Tue, Sep 08, 2015 at 10:57:06PM -0700, John Stultz wrote: > Recently an issue was reported that was difficult to detect except > by tweaking the adjtimex tick value, and noticing how quickly the > adjustment took to be made: > https://lkml.org/lkml/2015/9/1/488 > > Thus this patch introduces a new test which manipulates the adjtimex > tick value and validates the results are what we expect.
Great!
> + ppm = ((long long)tickval * MILLION)/10000 - MILLION;
I think this needs to be based on sysconf(_SC_CLK_TCK) or similar, since the user-space HZ is not 100 on all archs.
> + for (tick = 9000; tick < 11000; tick += 250) > + if (check_tick_adj(tick)) {
This too.
> + tx1.tick = 10000; > + adjtimex(&tx1);
And this too.
-- Miroslav Lichvar
| |