On 01/27/2015 05:03 PM, Paul E. McKenney wrote: > On Mon, Jan 26, 2015 at 10:08:04AM +0800, Lai Jiangshan wrote: >> > On 01/25/2015 05:18 AM, Paul E. McKenney wrote: >> > >>> > > >>> > > Good point! In my scenario, CPU 0 would not yet have switched away from >>> > > Task A. Hmmm... Yet Sasha really does see this failure. Will give it >>> > > some more thought. >>> > > >>> > > Any ideas? >> > >> > I don't known which commit was merged from the rcu-git-tree in Sasha's test >> > I try to review it. > If I had to guess, it would be 1d082fd06188 (Remove local_irq_disable() > in rcu_preempt_note_context_switch()), though his finding this might be > more directly related to increases in trinity's levels of stress.
Quick update from my end: I've stopped seeing this warning, but I've also stopped seeing warnings for the other RCU issue I've reported (https://lkml.org/lkml/2015/1/22/676) so I'm slightly unhappy about that. >> > We can fallback to git-bitsect if the reviews fails. > One (very unlikely) possibility is that Sasha's compiler is ignoring the > barrier() in rcu_preempt_qs(). I'm actually running the latest gcc (trunk) as well, so it's very possible that it was doing something stupid. Thanks, Sasha -- 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/
