rcu: Remove obsolete boost statistics for debugfs

The debugfs interface displayed statistics on RCU priority boosting,
but this interface has since been removed.  This commit therefore
removes the no-longer-used rcu_data structure's ->n_tasks_boosted,
->n_exp_boosts, and ->n_exp_boosts and 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>

2 files changed, 2 insertions, 12 deletions

diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index 6488a3b0e729..01abd1c4e5da 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -146,12 +146,6 @@ struct rcu_node {
                                 /*  boosting for this rcu_node structure. */
         unsigned int boost_kthread_status;
                                 /* State of boost_kthread_task for tracing. */
-        unsigned long n_tasks_boosted;
-                                /* Total number of tasks boosted. */
-        unsigned long n_exp_boosts;
-                                /* Number of tasks boosted for expedited GP. */
-        unsigned long n_normal_boosts;
-                                /* Number of tasks boosted for normal GP. */
 #ifdef CONFIG_RCU_NOCB_CPU
         struct swait_queue_head nocb_gp_wq[2];
                                 /* Place for rcu_nocb_kthread() to wait GP. */
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 7e31fb1e9fd8..0d552985b905 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -963,14 +963,10 @@ static int rcu_boost(struct rcu_node *rnp)
          * expedited grace period must boost all blocked tasks, including
          * those blocking the pre-existing normal grace period.
          */
-        if (rnp->exp_tasks != NULL) {
+        if (rnp->exp_tasks != NULL)
                 tb = rnp->exp_tasks;
-                rnp->n_exp_boosts++;
-        } else {
+        else
                 tb = rnp->boost_tasks;
-                rnp->n_normal_boosts++;
-        }
-        rnp->n_tasks_boosted++;
 
         /*
          * We boost task t by manufacturing an rt_mutex that appears to