On Sun, Oct 11, 2020 at 04:59:23PM +0200, Michael Weiß wrote: > @@ -79,6 +80,20 @@ static u64 get_iowait_time(struct kernel_cpustat *kcs, int > cpu) > > #endif > > +static void get_boottime(struct timespec64 *ts) > +{
> + ktime_t boottime; > + > + /* get kernel internal system boot timestamp */ > + getboottime64(ts); > + > + /* shift boot timestamp according to the timens offset */ > + boottime = timespec64_to_ktime(*ts); > + boottime = timens_ktime_to_host(CLOCK_BOOTTIME, boottime); timens_ktime_to_host is used to convert timens' time to host's time. Here it looks like we are using it in the opposite direction. I spent some time to figure out what is going on here. I think it worth to add a comment here. > + > + *ts = ktime_to_timespec64(boottime); I don't like all these conversions back and forth. Maybe something like this will look better: #ifdef CONFIG_TIME_NS if (current->nsproxy->time_ns != init_time_ns) { struct timens_offsets *ns_offsets; ns_offsets = ¤t->nsproxy->time_ns->offsets; ts = timespec64_sub(ts, timens_offsets->boottime); } #endif Thanks, Andrei