On Mon, Nov 3, 2014 at 4:28 PM, Pawel Moll <pawel.m...@arm.com> wrote: > From: Pawel Moll <m...@pawelmoll.com> > Thomas suggested solution which gets down to my original proposal for > sched/monotonic clock correlation - an additional sample type so events > can be "double stamped" using different clock sources providing > synchronisation points for later time approximation. I've just extended > the implementation with configuration value to select the clock source. > If the first patch (making perf timestamps monotonic) gets accepted, > there will be no immediate need for this one, but I'd like to gain some > feedback anyway. >
I have nothing intelligent to add to the potentional Thomas/Ingo showdown, but I do have a related thought. :) If you're going to add double-stamped packets, can you also add a syscall to read multiple clocks at once, atomically? Or can you otherwise add a non-perf mechanism to get at this data? Because the realtime to monotonic offset is really quite useful for things like this, and it seems silly to make people actually open a perf_event to get at it. --Andy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
