Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu

Pull RCU changes from Paul E. McKenney:

- Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar.

- Replace calls of RCU-bh and RCU-sched update-side functions
  to their vanilla RCU counterparts.  This series is a step
  towards complete removal of the RCU-bh and RCU-sched update-side
  functions.

  ( Note that some of these conversions are going upstream via their
    respective maintainers. )

- Documentation updates, including a number of flavor-consolidation
  updates from Joel Fernandes.

- Miscellaneous fixes.

- Automate generation of the initrd filesystem used for
  rcutorture testing.

- Convert spin_is_locked() assertions to instead use lockdep.

  ( Note that some of these conversions are going upstream via their
    respective maintainers. )

- SRCU updates, especially including a fix from Dennis Krein
  for a bag-on-head-class bug.

- RCU torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 60 insertions, 60 deletions

diff --git a/kernel/rcu/srcutiny.c b/kernel/rcu/srcutiny.c
index b46e6683f8c9..32dfd6522548 100644
--- a/kernel/rcu/srcutiny.c
+++ b/kernel/rcu/srcutiny.c
@@ -37,30 +37,30 @@ int rcu_scheduler_active __read_mostly;
 static LIST_HEAD(srcu_boot_list);
 static bool srcu_init_done;
 
-static int init_srcu_struct_fields(struct srcu_struct *sp)
+static int init_srcu_struct_fields(struct srcu_struct *ssp)
 {
-	sp->srcu_lock_nesting[0] = 0;
-	sp->srcu_lock_nesting[1] = 0;
-	init_swait_queue_head(&sp->srcu_wq);
-	sp->srcu_cb_head = NULL;
-	sp->srcu_cb_tail = &sp->srcu_cb_head;
-	sp->srcu_gp_running = false;
-	sp->srcu_gp_waiting = false;
-	sp->srcu_idx = 0;
-	INIT_WORK(&sp->srcu_work, srcu_drive_gp);
-	INIT_LIST_HEAD(&sp->srcu_work.entry);
+	ssp->srcu_lock_nesting[0] = 0;
+	ssp->srcu_lock_nesting[1] = 0;
+	init_swait_queue_head(&ssp->srcu_wq);
+	ssp->srcu_cb_head = NULL;
+	ssp->srcu_cb_tail = &ssp->srcu_cb_head;
+	ssp->srcu_gp_running = false;
+	ssp->srcu_gp_waiting = false;
+	ssp->srcu_idx = 0;
+	INIT_WORK(&ssp->srcu_work, srcu_drive_gp);
+	INIT_LIST_HEAD(&ssp->srcu_work.entry);
 	return 0;
 }
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 
-int __init_srcu_struct(struct srcu_struct *sp, const char *name,
+int __init_srcu_struct(struct srcu_struct *ssp, const char *name,
 		       struct lock_class_key *key)
 {
 	/* Don't re-initialize a lock while it is held. */
-	debug_check_no_locks_freed((void *)sp, sizeof(*sp));
-	lockdep_init_map(&sp->dep_map, name, key, 0);
-	return init_srcu_struct_fields(sp);
+	debug_check_no_locks_freed((void *)ssp, sizeof(*ssp));
+	lockdep_init_map(&ssp->dep_map, name, key, 0);
+	return init_srcu_struct_fields(ssp);
 }
 EXPORT_SYMBOL_GPL(__init_srcu_struct);
 
@@ -68,15 +68,15 @@ EXPORT_SYMBOL_GPL(__init_srcu_struct);
 
 /*
  * init_srcu_struct - initialize a sleep-RCU structure
- * @sp: structure to initialize.
+ * @ssp: structure to initialize.
  *
  * Must invoke this on a given srcu_struct before passing that srcu_struct
  * to any other function.  Each srcu_struct represents a separate domain
  * of SRCU protection.
  */
-int init_srcu_struct(struct srcu_struct *sp)
+int init_srcu_struct(struct srcu_struct *ssp)
 {
-	return init_srcu_struct_fields(sp);
+	return init_srcu_struct_fields(ssp);
 }
 EXPORT_SYMBOL_GPL(init_srcu_struct);
 
@@ -84,22 +84,22 @@ EXPORT_SYMBOL_GPL(init_srcu_struct);
 
 /*
  * cleanup_srcu_struct - deconstruct a sleep-RCU structure
- * @sp: structure to clean up.
+ * @ssp: structure to clean up.
  *
  * Must invoke this after you are finished using a given srcu_struct that
  * was initialized via init_srcu_struct(), else you leak memory.
  */
-void _cleanup_srcu_struct(struct srcu_struct *sp, bool quiesced)
+void _cleanup_srcu_struct(struct srcu_struct *ssp, bool quiesced)
 {
-	WARN_ON(sp->srcu_lock_nesting[0] || sp->srcu_lock_nesting[1]);
+	WARN_ON(ssp->srcu_lock_nesting[0] || ssp->srcu_lock_nesting[1]);
 	if (quiesced)
-		WARN_ON(work_pending(&sp->srcu_work));
+		WARN_ON(work_pending(&ssp->srcu_work));
 	else
-		flush_work(&sp->srcu_work);
-	WARN_ON(sp->srcu_gp_running);
-	WARN_ON(sp->srcu_gp_waiting);
-	WARN_ON(sp->srcu_cb_head);
-	WARN_ON(&sp->srcu_cb_head != sp->srcu_cb_tail);
+		flush_work(&ssp->srcu_work);
+	WARN_ON(ssp->srcu_gp_running);
+	WARN_ON(ssp->srcu_gp_waiting);
+	WARN_ON(ssp->srcu_cb_head);
+	WARN_ON(&ssp->srcu_cb_head != ssp->srcu_cb_tail);
 }
 EXPORT_SYMBOL_GPL(_cleanup_srcu_struct);
 
@@ -107,13 +107,13 @@ EXPORT_SYMBOL_GPL(_cleanup_srcu_struct);
  * Removes the count for the old reader from the appropriate element of
  * the srcu_struct.
  */
-void __srcu_read_unlock(struct srcu_struct *sp, int idx)
+void __srcu_read_unlock(struct srcu_struct *ssp, int idx)
 {
-	int newval = sp->srcu_lock_nesting[idx] - 1;
+	int newval = ssp->srcu_lock_nesting[idx] - 1;
 
-	WRITE_ONCE(sp->srcu_lock_nesting[idx], newval);
-	if (!newval && READ_ONCE(sp->srcu_gp_waiting))
-		swake_up_one(&sp->srcu_wq);
+	WRITE_ONCE(ssp->srcu_lock_nesting[idx], newval);
+	if (!newval && READ_ONCE(ssp->srcu_gp_waiting))
+		swake_up_one(&ssp->srcu_wq);
 }
 EXPORT_SYMBOL_GPL(__srcu_read_unlock);
 
@@ -127,24 +127,24 @@ void srcu_drive_gp(struct work_struct *wp)
 	int idx;
 	struct rcu_head *lh;
 	struct rcu_head *rhp;
-	struct srcu_struct *sp;
+	struct srcu_struct *ssp;
 
-	sp = container_of(wp, struct srcu_struct, srcu_work);
-	if (sp->srcu_gp_running || !READ_ONCE(sp->srcu_cb_head))
+	ssp = container_of(wp, struct srcu_struct, srcu_work);
+	if (ssp->srcu_gp_running || !READ_ONCE(ssp->srcu_cb_head))
 		return; /* Already running or nothing to do. */
 
 	/* Remove recently arrived callbacks and wait for readers. */
-	WRITE_ONCE(sp->srcu_gp_running, true);
+	WRITE_ONCE(ssp->srcu_gp_running, true);
 	local_irq_disable();
-	lh = sp->srcu_cb_head;
-	sp->srcu_cb_head = NULL;
-	sp->srcu_cb_tail = &sp->srcu_cb_head;
+	lh = ssp->srcu_cb_head;
+	ssp->srcu_cb_head = NULL;
+	ssp->srcu_cb_tail = &ssp->srcu_cb_head;
 	local_irq_enable();
-	idx = sp->srcu_idx;
-	WRITE_ONCE(sp->srcu_idx, !sp->srcu_idx);
-	WRITE_ONCE(sp->srcu_gp_waiting, true);  /* srcu_read_unlock() wakes! */
-	swait_event_exclusive(sp->srcu_wq, !READ_ONCE(sp->srcu_lock_nesting[idx]));
-	WRITE_ONCE(sp->srcu_gp_waiting, false); /* srcu_read_unlock() cheap. */
+	idx = ssp->srcu_idx;
+	WRITE_ONCE(ssp->srcu_idx, !ssp->srcu_idx);
+	WRITE_ONCE(ssp->srcu_gp_waiting, true);  /* srcu_read_unlock() wakes! */
+	swait_event_exclusive(ssp->srcu_wq, !READ_ONCE(ssp->srcu_lock_nesting[idx]));
+	WRITE_ONCE(ssp->srcu_gp_waiting, false); /* srcu_read_unlock() cheap. */
 
 	/* Invoke the callbacks we removed above. */
 	while (lh) {
@@ -161,9 +161,9 @@ void srcu_drive_gp(struct work_struct *wp)
 	 * at interrupt level, but the ->srcu_gp_running checks will
 	 * straighten that out.
 	 */
-	WRITE_ONCE(sp->srcu_gp_running, false);
-	if (READ_ONCE(sp->srcu_cb_head))
-		schedule_work(&sp->srcu_work);
+	WRITE_ONCE(ssp->srcu_gp_running, false);
+	if (READ_ONCE(ssp->srcu_cb_head))
+		schedule_work(&ssp->srcu_work);
 }
 EXPORT_SYMBOL_GPL(srcu_drive_gp);
 
@@ -171,7 +171,7 @@ EXPORT_SYMBOL_GPL(srcu_drive_gp);
  * Enqueue an SRCU callback on the specified srcu_struct structure,
  * initiating grace-period processing if it is not already running.
  */
-void call_srcu(struct srcu_struct *sp, struct rcu_head *rhp,
+void call_srcu(struct srcu_struct *ssp, struct rcu_head *rhp,
 	       rcu_callback_t func)
 {
 	unsigned long flags;
@@ -179,14 +179,14 @@ void call_srcu(struct srcu_struct *sp, struct rcu_head *rhp,
 	rhp->func = func;
 	rhp->next = NULL;
 	local_irq_save(flags);
-	*sp->srcu_cb_tail = rhp;
-	sp->srcu_cb_tail = &rhp->next;
+	*ssp->srcu_cb_tail = rhp;
+	ssp->srcu_cb_tail = &rhp->next;
 	local_irq_restore(flags);
-	if (!READ_ONCE(sp->srcu_gp_running)) {
+	if (!READ_ONCE(ssp->srcu_gp_running)) {
 		if (likely(srcu_init_done))
-			schedule_work(&sp->srcu_work);
-		else if (list_empty(&sp->srcu_work.entry))
-			list_add(&sp->srcu_work.entry, &srcu_boot_list);
+			schedule_work(&ssp->srcu_work);
+		else if (list_empty(&ssp->srcu_work.entry))
+			list_add(&ssp->srcu_work.entry, &srcu_boot_list);
 	}
 }
 EXPORT_SYMBOL_GPL(call_srcu);
@@ -194,13 +194,13 @@ EXPORT_SYMBOL_GPL(call_srcu);
 /*
  * synchronize_srcu - wait for prior SRCU read-side critical-section completion
  */
-void synchronize_srcu(struct srcu_struct *sp)
+void synchronize_srcu(struct srcu_struct *ssp)
 {
 	struct rcu_synchronize rs;
 
 	init_rcu_head_on_stack(&rs.head);
 	init_completion(&rs.completion);
-	call_srcu(sp, &rs.head, wakeme_after_rcu);
+	call_srcu(ssp, &rs.head, wakeme_after_rcu);
 	wait_for_completion(&rs.completion);
 	destroy_rcu_head_on_stack(&rs.head);
 }
@@ -219,13 +219,13 @@ void __init rcu_scheduler_starting(void)
  */
 void __init srcu_init(void)
 {
-	struct srcu_struct *sp;
+	struct srcu_struct *ssp;
 
 	srcu_init_done = true;
 	while (!list_empty(&srcu_boot_list)) {
-		sp = list_first_entry(&srcu_boot_list,
+		ssp = list_first_entry(&srcu_boot_list,
 				      struct srcu_struct, srcu_work.entry);
-		list_del_init(&sp->srcu_work.entry);
-		schedule_work(&sp->srcu_work);
+		list_del_init(&ssp->srcu_work.entry);
+		schedule_work(&ssp->srcu_work);
 	}
 }