rcu: Remove obsolete callback-invocation statistics for debugfs

The debugfs interface displayed statistics on RCU callback invocation but
this interface has since been removed.  This commit therefore removes the
no-longer-used rcu_data structure's ->n_cbs_invoked and ->n_nocbs_invoked
fields along with their updates.

If this information proves necessary in the future, the corresponding
event traces will be added.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

3 files changed, 0 insertions, 4 deletions

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 66c73a214cff..8e0711954bbf 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -2691,7 +2691,6 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
         /* Update counts and requeue any remaining callbacks. */
         rcu_segcblist_insert_done_cbs(&rdp->cblist, &rcl);
         smp_mb(); /* List handling before counting for rcu_barrier(). */
-        rdp->n_cbs_invoked += count;
         rcu_segcblist_insert_count(&rdp->cblist, &rcl);
 
         /* Reinstate batch limit if we have worked down the excess. */
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index 01abd1c4e5da..b258fac73524 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -211,8 +211,6 @@ struct rcu_data {
                                         /* different grace periods. */
         long            qlen_last_fqs_check;
                                         /* qlen at last check for QS forcing */
-        unsigned long   n_cbs_invoked;  /* count of RCU cbs invoked. */
-        unsigned long   n_nocbs_invoked; /* count of no-CBs RCU cbs invoked. */
         unsigned long   n_force_qs_snap;
                                         /* did other CPU force QS recently? */
         long            blimit;         /* Upper limit on a processed batch */
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 0d552985b905..1c2d58a85511 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -2243,7 +2243,6 @@ static int rcu_nocb_kthread(void *arg)
                 smp_mb__before_atomic();  /* _add after CB invocation. */
                 atomic_long_add(-c, &rdp->nocb_q_count);
                 atomic_long_add(-cl, &rdp->nocb_q_count_lazy);
-                rdp->n_nocbs_invoked += c;
         }
         return 0;
 }