On Thu, Oct 10, 2019 at 04:41:38PM +0800, Li RongQing wrote: > if perf counter is used as nmi watchdog, and twice nmi in soft > watchdog sample period will trigger hard lockup > > make sure left time is not less than soft watchdog period by > compared with 3/5 period to skip forward, since soft watchdog > sample period is 2/5 of watchdog_thresh, nmi watchdog sample > period, computed by set_sample_period > > Signed-off-by: Li RongQing <[email protected]> > --- > arch/x86/events/core.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c > index 7b21455d7504..1f5309456d4c 100644 > --- a/arch/x86/events/core.c > +++ b/arch/x86/events/core.c > @@ -1196,7 +1196,11 @@ int x86_perf_event_set_period(struct perf_event *event) > /* > * If we are way outside a reasonable range then just skip forward: > */ > +#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF > + if (unlikely(left <= -(period * 3 / 5))) { > +#else > if (unlikely(left <= -period)) { > +#endif
NAK. This is 100% the wrong place to do anything like that.
