On Thu, 2010-05-13 at 06:16 -0500, pac...@kosh.dhis.org wrote: > Benjamin Herrenschmidt writes: > > > > Well, first it should be called once per second, not 60 times per > > second, so something is wrong there... > > Actually I think it was happening a lot more than 60 times per second, and > klogd was losing most of the messages because they came too fast. When > running the new kernel, vmstat shows 170000 context switches per second (and > CPU usage never going below 5%) even when everything should be idle. > > My next experiment was to hack rtas_init to return 0 unconditionally. Now > everything still runs fine, and the context switches per second are back down > in the 2-digit range. > > > > > Then, it wouldn't surprise me if the Pegasos RTAS didn't implement > > the event scan properly. Maybe we failed silently before that ? I > > doubt it's necessary there anyways. > > If I'm reading things correctly, rtas-event-scan-rate is the key to the > frequency of attempts. And rtasd.c didn't expect this: > > $ od -t x1 /proc/device-tree/rtas/rtas-event-scan-rate > 0000000 00 00 00 00 > 0000004
Ok, that gives us a good thing to use to not do the scanning then. If that's 0 then we assume it's a bogus OF and we disable the scan completely. I'll do a patch later today, though feel free to beat me to it. Cheers, Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev