Re: Ktimer / -rt9 (+custom) monotonic_clock going backwards.

[Ingo Molnar <mingo@elte.hu>]

* Steven Rostedt <rostedt@goodmis.org> wrote:

> static inline nsec_t __get_nsec_offset(void)
> {
> 	cycle_t cycle_now, cycle_delta;
> 	nsec_t ns_offset;
> 
> 	/* read clocksource */
> 	cycle_now = read_clocksource(clock);
> 
> 	/* calculate the delta since the last timeofday_periodic_hook */
> 	cycle_delta = (cycle_now - cycle_last) & clock->mask;
> 
> 	/* convert to nanoseconds */
> 	ns_offset = cyc2ns(clock, ntp_adj, cycle_delta);
> 
> 	/* Special case for jiffies tick/offset based systems
> 	 * add arch specific offset
> 	 */
> 	ns_offset += arch_getoffset();
> 
> 	return ns_offset;
> }
> 
> cycle_now is 32 bits.  If the clocksource overflows (which it can in 
> 30 seconds) the cyclec_delta will be wrong.

isnt cycle_t 64 bits?

	Ingo
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