From 1c50b728c3e734150b8a4a8310ce3e01bc5c70be Mon Sep 17 00:00:00 2001 From: Mathieu Desnoyers Date: Mon, 29 Sep 2008 11:06:46 -0400 Subject: [PATCH] rcu: add rcu_read_lock_sched() / rcu_read_unlock_sched() Add rcu_read_lock_sched() and rcu_read_unlock_sched() to rcupdate.h to match the recently added write-side call_rcu_sched() and rcu_barrier_sched(). They also match the no-so-recently-added synchronize_sched(). It will help following matching use of the update/read lock primitives. Those new read lock will replace preempt_disable()/enable() used in pair with RCU-classic synchronization. Signed-off-by: Mathieu Desnoyers Acked-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- include/linux/rcupdate.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index e8b4039cfb2f..86f1f5e43e33 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -132,6 +132,26 @@ struct rcu_head { */ #define rcu_read_unlock_bh() __rcu_read_unlock_bh() +/** + * rcu_read_lock_sched - mark the beginning of a RCU-classic critical section + * + * Should be used with either + * - synchronize_sched() + * or + * - call_rcu_sched() and rcu_barrier_sched() + * on the write-side to insure proper synchronization. + */ +#define rcu_read_lock_sched() preempt_disable() + +/* + * rcu_read_unlock_sched - marks the end of a RCU-classic critical section + * + * See rcu_read_lock_sched for more information. + */ +#define rcu_read_unlock_sched() preempt_enable() + + + /** * rcu_dereference - fetch an RCU-protected pointer in an * RCU read-side critical section. This pointer may later -- 2.39.2