On Fri, Dec 5, 2014 at 1:03 PM, Arnd Bergmann <a...@arndb.de> wrote: > On Friday 05 December 2014 13:00:22 Nicolas Pitre wrote: >> >> BTW this is worth applying despite the on-going discussion with Arnd >> on a separate optimization. > > Agreed > >> On Wed, 3 Dec 2014, Nicolas Pitre wrote: >> >> > At least on ARM, do_div() is optimized to turn constant divisors into >> > an inline multiplication by the reciprocal value at compile time. >> > However this optimization is missed entirely whenever ktime_divns() is >> > used and the slow out-of-line division code is used all the time. >> > >> > Let ktime_divns() use do_div() inline whenever the divisor is constant >> > and small enough. This will make things like ktime_to_us() and >> > ktime_to_ms() much faster. >> > >> > Signed-off-by: Nicolas Pitre <n...@linaro.org> > > Acked-by: Arnd Bergmann <a...@arndb.de>
Ok, I've queued the original patch up for testing. thanks -john -- 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/
