On Tue, 2013-10-29 at 09:58 +0100, Markus Pargmann wrote: > On Tue, Oct 29, 2013 at 01:34:48AM -0700, Joe Perches wrote: > > On Tue, 2013-10-29 at 09:27 +0100, Markus Pargmann wrote: > > > This patch speeds up the rx_poll function by reducing the number of > > > register reads. > > [] > > > 125kbit: > > > Function Hit Time Avg > > > s^2 > > > -------- --- ---- --- > > > --- > > > c_can_do_rx_poll 63960 10168178 us 158.977 > > > us 1493056 us > > > With patch: > > > c_can_do_rx_poll 63939 4268457 us 66.758 us > > > 818790.9 us > > > > > > 1Mbit: > > > Function Hit Time Avg > > > s^2 > > > -------- --- ---- --- > > > --- > > > c_can_do_rx_poll 69489 30049498 us 432.435 > > > us 9271851 us > > > With patch: > > > c_can_do_rx_poll 103034 24220362 us 235.071 > > > us 6016656 us [] > Yes I just measured the timings again: [] > ./perf_can_test.sh 125000 30 [] > c_can_do_rx_poll 63941 3764057 us 58.867 us > 776162.2 us
Good, it's slightly faster still. > ./perf_can_test.sh 1000000 30 [] > c_can_do_rx_poll 207109 24322185 us 117.436 us > 171469047 us [] > It is interesting that the number of hits for c_can_do_rx_poll is twice as > much > as it was with find_next_bit. How is this possible? Any idea? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
