Messages in this thread Patch in this message | | | Date | Tue, 16 Mar 2010 19:09:21 +0800 | From | Lai Jiangshan <> | Subject | [PATCH -tip] rcu: local_irq_disable() also delimits RCU_SCHED read-site critical sections |
| |
It is documented that local_irq_disable() also delimits RCU_SCHED read-site critical sections. See the document of synchronize_sched() or Documentation/RCU/whatisRCU.txt.
So we have to test irqs_disabled() in rcu_read_lock_sched_held(). Otherwise rcu-lockdep brings incorrect complaint.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> --- diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 3024050..2ce5674 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -160,7 +160,7 @@ static inline int rcu_read_lock_sched_held(void) return 1; if (debug_locks) lockdep_opinion = lock_is_held(&rcu_sched_lock_map); - return lockdep_opinion || preempt_count() != 0; + return lockdep_opinion || preempt_count() != 0 || irqs_disabled(); } #else /* #ifdef CONFIG_PREEMPT */ static inline int rcu_read_lock_sched_held(void) @@ -191,7 +191,7 @@ static inline int rcu_read_lock_bh_held(void) #ifdef CONFIG_PREEMPT static inline int rcu_read_lock_sched_held(void) { - return !rcu_scheduler_active || preempt_count() != 0; + return !rcu_scheduler_active || preempt_count() != 0 || irqs_disabled(); } #else /* #ifdef CONFIG_PREEMPT */ static inline int rcu_read_lock_sched_held(void)
| |