Messages in this thread | | | Date | Fri, 28 Feb 2014 14:23:28 -0800 | From | "Paul E. McKenney" <> | Subject | Re: perf_fuzzer compiled for x32 causes reboot |
| |
On Fri, Feb 28, 2014 at 05:05:53PM -0500, Steven Rostedt wrote: > On Fri, 28 Feb 2014 22:55:11 +0100 > Peter Zijlstra <peterz@infradead.org> wrote: > > > On Fri, Feb 28, 2014 at 01:51:50PM -0800, Paul E. McKenney wrote: > > > On Fri, Feb 28, 2014 at 10:27:00PM +0100, Peter Zijlstra wrote: > > > > On Fri, Feb 28, 2014 at 01:17:33PM -0800, Paul E. McKenney wrote: > > > > > This code isn't running in idle context is it? If so, RCU will happily > > > > > free out from under it. CONFIG_PROVE_RCU should detect this sort of thing, > > > > > though. > > > > > > > > Well, interrupts/NMIs can happen when idle, but the interrupt/NMI > > > > entry code deals with the idle state AFAIK. > > > > > > Yep, rcu_irq_enter() and rcu_nmi_enter() deal with that. More worried > > > about this being code invoked from some energy-efficiency driver or > > > another within the idle loop. > > > > Right, so any tracepoint can end up there; but I thought there was > > already the rule that tracepoints needed RCU enabled. > > There is and we have special tracepoint caller for those cases we want a > tracepoint out of RCU scope. These will reactivate rcu in the > tracepoint code. > > trace_<tp_name>_rcuidle(...)
OK, I finally looked at the emails leading up to this in the thread... I believe that I am doing premature debugging.
Thanx, Paul
| |