On Mon, 2007-07-30 at 11:22 +0200, Ingo Molnar wrote: > * Daniel Walker <dwalker@xxxxxxxxxx> wrote: > > > + /* > > + * If our rcu_read_lock_nesting went negative, likely > > + * something is wrong.. > > + */ > > + WARN_ON(current->rcu_read_lock_nesting < 0); > > have you actually caught any rcu locking problem this way? Double > unlocks should be caught by lockdep already, at a higher level. > > in any case i've added a slightly different form of this change to the > -rt queue that will also check for counter overflows. But i'm not sure > we want to litter the code with trivial checks like this, so i'm keeping > it separate and if it does not trigger anything real i'll remove it. I haven't caught anything with it, but this code would have made it much easier to catch the single rcu unlock in sys_sched_yield() which was silent in PREEMPT_RT, and hung !PREEMPT_RT .. It's fine with me, if you have another method. Daniel - 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
