Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RCU updates from Ingo Molnar:
 "The biggest RCU changes in this cycle were:

   - 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"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (112 commits)
  rcutorture: Don't do busted forward-progress testing
  rcutorture: Use 100ms buckets for forward-progress callback histograms
  rcutorture: Recover from OOM during forward-progress tests
  rcutorture: Print forward-progress test age upon failure
  rcutorture: Print time since GP end upon forward-progress failure
  rcutorture: Print histogram of CB invocation at OOM time
  rcutorture: Print GP age upon forward-progress failure
  rcu: Print per-CPU callback counts for forward-progress failures
  rcu: Account for nocb-CPU callback counts in RCU CPU stall warnings
  rcutorture: Dump grace-period diagnostics upon forward-progress OOM
  rcutorture: Prepare for asynchronous access to rcu_fwd_startat
  torture: Remove unnecessary "ret" variables
  rcutorture: Affinity forward-progress test to avoid housekeeping CPUs
  rcutorture: Break up too-long rcu_torture_fwd_prog() function
  rcutorture: Remove cbflood facility
  torture: Bring any extra CPUs online during kernel startup
  rcutorture: Add call_rcu() flooding forward-progress tests
  rcutorture/formal: Replace synchronize_sched() with synchronize_rcu()
  tools/kernel.h: Replace synchronize_sched() with synchronize_rcu()
  net/decnet: Replace rcu_barrier_bh() with rcu_barrier()
  ...

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);
         }
 }