Messages in this thread | | | Subject | Re: [PATCH tip/core/rcu 01/15] rcu: Add PROVE_RCU_DELAY to provoke difficult races | From | Peter Zijlstra <> | Date | Fri, 07 Sep 2012 08:54:33 +0200 |
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On Thu, 2012-09-06 at 13:51 -0700, Paul E. McKenney wrote: > On Thu, Sep 06, 2012 at 04:38:32PM +0200, Peter Zijlstra wrote: > > On Thu, 2012-08-30 at 11:56 -0700, Paul E. McKenney wrote: > > > +#ifdef CONFIG_PROVE_RCU_DELAY > > > + udelay(10); /* Make preemption more probable. */ > > cond_resched(); /* for extra fun? */ > > The additional fun could include "scheduling while atomic", so I will > pass. ;-) > > (The problem is that __rcu_read_unlock() can be called with interrupts > disabled, among other things.)
Hmm, too bad. Without a preemption point here you're relying on forced preemption, which of course can only happen on PREEMPT=y kernels.
> > > +#endif /* #ifdef CONFIG_PROVE_RCU_DELAY */ > > > > >
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