Hi! On 11:01 Sun 15 May , Greg KH wrote:
On Sun, May 15, 2011 at 01:48:43PM -0400, Robert P. J. Day wrote: ...
ok, good to know. i assume, then, that it's fairly pointless to use the value of "jiffies" for anything that requires even moderate accuracy. i was poking around the timer code, and i can see this in kernel/time/timekeeping.c:
No, never access jiffies directly, use the correct delay and timer functions instead, they will handle things properly. And that's the way to get correct accuracy if you need it.
When switchint from jiffies+timers to hrtimers what should be used as a monotonic time source? ktime_get()? What am I supposed to do if timekeeping_valid_for_hres() returns 0? Can I ignore this? What does it mean this highres timer are not available during system startup? Are they running with lower resolution or not at all? -Michi