Messages in this thread | | | From | Arnd Bergmann <> | Subject | Re: [PATCH v3 0/3] perf: User/kernel time correlation and event generation | Date | Tue, 04 Nov 2014 09:01:31 +0100 |
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On Monday 03 November 2014 17:11:53 John Stultz wrote: > I've got some thoughts on what a possible interface that wouldn't be > awful could look like, but I'm still hesitant because I don't really > know if exposing this sort of data is actually a good idea long term.
I was also thinking (while working on an unrelated patch) we could use a system call like
int clock_getoffset(clockid_t clkid, struct timespec *offs);
that returns the current offset between CLOCK_REALTIME and the requested timebase. It is of course racy, but so is every use of CLOCK_REALTIME. We could also use a reference other than CLOCK_REALTIME that might be more stable, but passing two arbitrary clocks as input would make this much more complex to implement.
Arnd
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