rcu: Update documentation of rcu_read_unlock()

Since commit b4abf91 ("rtmutex: Make wait_lock irq safe") the explanation in rcu_read_unlock() documentation about irq unsafe rtmutex wait_lock is no longer valid. Remove it to prevent kernel developers reading the documentation to rely on it. Suggested-by: Eric W. Biederman <[email protected]> Signed-off-by: Anna-Maria Gleixner <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Reviewed-by: Paul E. McKenney <[email protected]> Acked-by: "Eric W. Biederman" <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected]
akeromi · Jun 10, 2018 · ec84b27 · ec84b27
1 parent cd77849
commit ec84b27
Showing 1 changed file with 1 addition and 3 deletions.
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
@@ -652,9 +652,7 @@ static inline void rcu_read_lock(void)
  * Unfortunately, this function acquires the scheduler's runqueue and
  * priority-inheritance spinlocks.  This means that deadlock could result
  * if the caller of rcu_read_unlock() already holds one of these locks or
- * any lock that is ever acquired while holding them; or any lock which
- * can be taken from interrupt context because rcu_boost()->rt_mutex_lock()
- * does not disable irqs while taking ->wait_lock.
+ * any lock that is ever acquired while holding them.
  *
  * That said, RCU readers are never priority boosted unless they were
  * preempted.  Therefore, one way to avoid deadlock is to make sure