rcu: add rcu_read_lock_sched() / rcu_read_unlock_sched() (1c50b728) · Commits · e / devices / android_kernel_fairphone_FP3

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 <mathieu.desnoyers@polymtl.ca> Acked-by:

Peter Zijlstra <peterz@infradead.org> Signed-off-by:

Ingo Molnar <mingo@elte.hu>

include/linux/rcupdate.h

+20 −0

Original line number	Diff line number	Diff line
		@@ -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