EXP: rcu: Add more debugging info to assertion
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 3539e2fd..a8db2a7 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -2139,8 +2139,22 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
*/
rcu_for_each_node_breadth_first(rsp, rnp) {
raw_spin_lock_irq_rcu_node(rnp);
- if (WARN_ON_ONCE(rcu_preempt_blocked_readers_cgp(rnp)))
- pr_info("%s: grp: %d-%d level: %d\n", __func__, rnp->grplo, rnp->grphi, rnp->level);
+#ifdef CONFIG_PREEMPT_RCU
+ if (WARN_ON_ONCE(rcu_preempt_blocked_readers_cgp(rnp))) {
+ int i;
+ struct task_struct *t;
+
+ pr_info("%s: grp: %d-%d level: %d ->gp_tasks %p ->exp_tasks %p\n", __func__, rnp->grplo, rnp->grphi, rnp->level, rnp->gp_tasks, rnp->exp_tasks);
+ pr_cont("\t->blkd_tasks");
+ i = 0;
+ list_for_each_entry(t, &rnp->blkd_tasks, rcu_node_entry) {
+ pr_cont(" %p", t);
+ if (++i >= 10)
+ break;
+ }
+ pr_cont("\n");
+ }
+#endif /* #ifdef CONFIG_PREEMPT_RCU */
WARN_ON_ONCE(rnp->qsmask);
WRITE_ONCE(rnp->completed, rsp->gpnum);
rdp = this_cpu_ptr(rsp->rda);
