rcu: Document same-context read-side constraints (3842a083) · Commits · 戴 / test

include/linux/rcupdate.h

+15 −0

Original line number	Diff line number	Diff line
		@@ -265,6 +265,11 @@ extern int debug_lockdep_rcu_enabled(void);
		*
		* Checks debug_lockdep_rcu_enabled() to prevent false positives during boot
		* and while lockdep is disabled.
		*
		* Note that rcu_read_lock() and the matching rcu_read_unlock() must
		* occur in the same context, for example, it is illegal to invoke
		* rcu_read_unlock() in process context if the matching rcu_read_lock()
		* was invoked from within an irq handler.
		*/
		static inline int rcu_read_lock_held(void)
		{
		@@ -689,6 +694,11 @@ static inline void rcu_read_unlock(void)
		* critical sections in interrupt context can use just rcu_read_lock(),
		* though this should at least be commented to avoid confusing people
		* reading the code.
		*
		* Note that rcu_read_lock_bh() and the matching rcu_read_unlock_bh()
		* must occur in the same context, for example, it is illegal to invoke
		* rcu_read_unlock_bh() from one task if the matching rcu_read_lock_bh()
		* was invoked from some other task.
		*/
		static inline void rcu_read_lock_bh(void)
		{
		@@ -716,6 +726,11 @@ static inline void rcu_read_unlock_bh(void)
		* are being done using call_rcu_sched() or synchronize_rcu_sched().
		* Read-side critical sections can also be introduced by anything that
		* disables preemption, including local_irq_disable() and friends.
		*
		* Note that rcu_read_lock_sched() and the matching rcu_read_unlock_sched()
		* must occur in the same context, for example, it is illegal to invoke
		* rcu_read_unlock_sched() from process context if the matching
		* rcu_read_lock_sched() was invoked from an NMI handler.
		*/
		static inline void rcu_read_lock_sched(void)
		{

include/linux/srcu.h

+5 −0

Original line number	Diff line number	Diff line
		@@ -158,6 +158,11 @@ static inline int srcu_read_lock_held(struct srcu_struct *sp)
		* one way to indirectly wait on an SRCU grace period is to acquire
		* a mutex that is held elsewhere while calling synchronize_srcu() or
		* synchronize_srcu_expedited().
		*
		* Note that srcu_read_lock() and the matching srcu_read_unlock() must
		* occur in the same context, for example, it is illegal to invoke
		* srcu_read_unlock() in an irq handler if the matching srcu_read_lock()
		* was invoked in process context.
		*/
		static inline int srcu_read_lock(struct srcu_struct *sp) __acquires(sp)
		{

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