Re: rtc_gettimeofday VS. do_gettimeofday

[George Anzinger]

Abhishek Rai wrote:
> Hi,
> I need a mechanism to get accurate timeofday from inside the kernel. 
> Though rtc_gettimeofday() and do_gettimeofday() both look appropriate, is 
> there a reason to prefer one over the other ?

Well, gettimeofday is corrected by ntp, if that matters.  It also has a 
resolution down to the micro second.

The rtc, on the other hand, is an I/O device (i.e. slower) and only goes to the 
second.

If all you need is second resolution the faster way is to use the seconds part 
of xtime.  This is available as CURRENT_TIME which is defined in 
include/linux/sched.h.
--
George Anzinger   george@xxxxxxxxxx
High-res-timers:  http://sourceforge.net/projects/high-res-timers/
Preemption patch: http://www.kernel.org/pub/linux/kernel/people/rml

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