Commit 27fdb35f authored by Paul E. McKenney's avatar Paul E. McKenney Committed by Linus Torvalds
Browse files

doc: Fix various RCU docbook comment-header problems 



Because many of RCU's files have not been included into docbook, a
number of errors have accumulated.  This commit fixes them.

Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 533966c8

include/linux/rculist.h

+1 −1
Original line number Diff line number Diff line
@@ -276,7 +276,7 @@ static inline void list_splice_tail_init_rcu(struct list_head *list, 
#define list_entry_rcu(ptr, type, member) \

	container_of(lockless_dereference(ptr), type, member)



/**

/*

 * Where are list_empty_rcu() and list_first_entry_rcu()?

 *

 * Implementing those functions following their counterparts list_empty() and

include/linux/rcupdate.h

+14 −8
Original line number Diff line number Diff line
@@ -523,7 +523,7 @@ static inline void rcu_preempt_sleep_check(void) { } 
 * Return the value of the specified RCU-protected pointer, but omit

 * both the smp_read_barrier_depends() and the READ_ONCE().  This

 * is useful in cases where update-side locks prevent the value of the

 * pointer from changing.  Please note that this primitive does -not-

 * pointer from changing.  Please note that this primitive does *not*

 * prevent the compiler from repeating this reference or combining it

 * with other references, so it should not be used without protection

 * of appropriate locks.
@@ -568,7 +568,7 @@ static inline void rcu_preempt_sleep_check(void) { } 
 * is handed off from RCU to some other synchronization mechanism, for

 * example, reference counting or locking.  In C11, it would map to

 * kill_dependency().  It could be used as follows:

 *

 * ``

 *	rcu_read_lock();

 *	p = rcu_dereference(gp);

 *	long_lived = is_long_lived(p);
@@ -579,6 +579,7 @@ static inline void rcu_preempt_sleep_check(void) { } 
 *			p = rcu_pointer_handoff(p);

 *	}

 *	rcu_read_unlock();

 *``

 */

#define rcu_pointer_handoff(p) (p)
@@ -778,18 +779,21 @@ static inline notrace void rcu_read_unlock_sched_notrace(void) 


/**

 * RCU_INIT_POINTER() - initialize an RCU protected pointer

 * @p: The pointer to be initialized.

 * @v: The value to initialized the pointer to.

 *

 * Initialize an RCU-protected pointer in special cases where readers

 * do not need ordering constraints on the CPU or the compiler.  These

 * special cases are:

 *

 * 1.	This use of RCU_INIT_POINTER() is NULLing out the pointer -or-

 * 1.	This use of RCU_INIT_POINTER() is NULLing out the pointer *or*

 * 2.	The caller has taken whatever steps are required to prevent

 *	RCU readers from concurrently accessing this pointer -or-

 *	RCU readers from concurrently accessing this pointer *or*

 * 3.	The referenced data structure has already been exposed to

 *	readers either at compile time or via rcu_assign_pointer() -and-

 *	a.	You have not made -any- reader-visible changes to

 *		this structure since then -or-

 *	readers either at compile time or via rcu_assign_pointer() *and*

 *

 *	a.	You have not made *any* reader-visible changes to

 *		this structure since then *or*

 *	b.	It is OK for readers accessing this structure from its

 *		new location to see the old state of the structure.  (For

 *		example, the changes were to statistical counters or to
@@ -805,7 +809,7 @@ static inline notrace void rcu_read_unlock_sched_notrace(void) 
 * by a single external-to-structure RCU-protected pointer, then you may

 * use RCU_INIT_POINTER() to initialize the internal RCU-protected

 * pointers, but you must use rcu_assign_pointer() to initialize the

 * external-to-structure pointer -after- you have completely initialized

 * external-to-structure pointer *after* you have completely initialized

 * the reader-accessible portions of the linked structure.

 *

 * Note that unlike rcu_assign_pointer(), RCU_INIT_POINTER() provides no
@@ -819,6 +823,8 @@ static inline notrace void rcu_read_unlock_sched_notrace(void) 


/**

 * RCU_POINTER_INITIALIZER() - statically initialize an RCU protected pointer

 * @p: The pointer to be initialized.

 * @v: The value to initialized the pointer to.

 *

 * GCC-style initialization for an RCU-protected pointer in a structure field.

 */

include/linux/srcu.h

+1 −0
Original line number Diff line number Diff line
@@ -78,6 +78,7 @@ void synchronize_srcu(struct srcu_struct *sp); 


/**

 * srcu_read_lock_held - might we be in SRCU read-side critical section?

 * @sp: The srcu_struct structure to check

 *

 * If CONFIG_DEBUG_LOCK_ALLOC is selected, returns nonzero iff in an SRCU

 * read-side critical section.  In absence of CONFIG_DEBUG_LOCK_ALLOC,

kernel/rcu/srcutree.c

+1 −1
Original line number Diff line number Diff line
@@ -854,7 +854,7 @@ void __call_srcu(struct srcu_struct *sp, struct rcu_head *rhp, 
/**

 * call_srcu() - Queue a callback for invocation after an SRCU grace period

 * @sp: srcu_struct in queue the callback

 * @head: structure to be used for queueing the SRCU callback.

 * @rhp: structure to be used for queueing the SRCU callback.

 * @func: function to be invoked after the SRCU grace period

 *

 * The callback function will be invoked some time after a full SRCU

kernel/rcu/sync.c

+6 −3
Original line number Diff line number Diff line
@@ -85,6 +85,9 @@ void rcu_sync_init(struct rcu_sync *rsp, enum rcu_sync_type type) 
}



/**

 * rcu_sync_enter_start - Force readers onto slow path for multiple updates

 * @rsp: Pointer to rcu_sync structure to use for synchronization

 *

 * Must be called after rcu_sync_init() and before first use.

 *

 * Ensures rcu_sync_is_idle() returns false and rcu_sync_{enter,exit}()
@@ -142,7 +145,7 @@ void rcu_sync_enter(struct rcu_sync *rsp) 


/**

 * rcu_sync_func() - Callback function managing reader access to fastpath

 * @rsp: Pointer to rcu_sync structure to use for synchronization

 * @rhp: Pointer to rcu_head in rcu_sync structure to use for synchronization

 *

 * This function is passed to one of the call_rcu() functions by

 * rcu_sync_exit(), so that it is invoked after a grace period following the
@@ -158,9 +161,9 @@ void rcu_sync_enter(struct rcu_sync *rsp) 
 * rcu_sync_exit().  Otherwise, set all state back to idle so that readers

 * can again use their fastpaths.

 */

static void rcu_sync_func(struct rcu_head *rcu)

static void rcu_sync_func(struct rcu_head *rhp)

{

	struct rcu_sync *rsp = container_of(rcu, struct rcu_sync, cb_head);

	struct rcu_sync *rsp = container_of(rhp, struct rcu_sync, cb_head);

	unsigned long flags;



	BUG_ON(rsp->gp_state != GP_PASSED);