| Date | Wed, 1 Feb 2012 21:13:37 -0800 | From | Josh Triplett <> | Subject | Re: [PATCH RFC tip/core/rcu 24/41] rcu: Check for idle-loop entry while in RCU read-side critical section |
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On Wed, Feb 01, 2012 at 11:41:42AM -0800, Paul E. McKenney wrote: > --- a/kernel/rcutree.c > +++ b/kernel/rcutree.c > @@ -366,6 +366,20 @@ static void rcu_idle_enter_common(struct rcu_dynticks *rdtp, long long oldval) > atomic_inc(&rdtp->dynticks); > smp_mb__after_atomic_inc(); /* Force ordering with next sojourn. */ > WARN_ON_ONCE(atomic_read(&rdtp->dynticks) & 0x1); > + > + /* > + * The idle task is not permitted to enter the idle loop while > + * in an RCU read-side critical section. > + */ > + rcu_lockdep_assert(!lock_is_held(&rcu_lock_map), > + "Illegal idle entry in RCU read-side " > + "critical section."); > + rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map), > + "Illegal idle entry in RCU-bh read-side " > + "critical section."); > + rcu_lockdep_assert(!lock_is_held(&rcu_sched_lock_map), > + "Illegal idle entry in RCU-sched read-side " > + "critical section.");
Quoting a paragraph I added to Documentation/CodingStyle:
> Statements longer than 80 columns will be broken into sensible chunks, unless > exceeding 80 columns significantly increases readability and does not hide > information. Descendants are always substantially shorter than the parent and > are placed substantially to the right. The same applies to function headers > with a long argument list. However, never break user-visible strings such as > printk messages, because that breaks the ability to grep for them.
So, please don't break those strings across multiple lines. The same goes for the similar rcu_lockdep_assert strings added in a previous patch in this series.
- Josh Triplett
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