From: Ingo Molnar <mingo@xxxxxxx> Date: Sun, 25 Feb 2007 07:27:47 +0100 > > * Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> wrote: > > > I got the following running stock 2.6.20-rt8 on an 4-CPU 1.8GHz > > Opteron box. The machine continued to run a few rounds of kernbench > > and LTP. Looks a bit scary -- a tasklet was "stolen" from > > __tasklet_action(). > > > > Thoughts? In the meantime, kicking it off again to see if it repeats. > > > BUG: at kernel/softirq.c:559 __tasklet_action() > > this seems to happen very sporadically. Seems to happen more likely on > hyperthreading CPUs. It is very likely caused by the > redesign-tasklet-locking-to-be-sane patch below - which is a quick hack > of mine from early -rt days. Can you see any obvious bug in it? The > cmpxchg logic is certainly a bit ... tricky, locking-wise. Ingo, please don't use cmpxchg() in generic code, we support several processors that simply cannot do it. Instead of saying "it's just something special in -rt for now", take it out now so that what you do eventually push upstream does get tested. Thanks. - To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
