The show_rcu_tasks_trace_gp_kthread() is used by rcutorture to diagnose
bugs involving the RCU Tasks Trace grace-period kthread, which now no
longer exists.  This commit therefore removes this function.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <bpf@vger.kernel.org>
---
 kernel/rcu/rcu.h        | 5 -----
 kernel/rcu/rcutorture.c | 1 -
 kernel/rcu/tasks.h      | 6 ------
 3 files changed, 12 deletions(-)

diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index 9cf01832a6c3d1..b397572b4a5331 100644
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -673,11 +673,6 @@ void show_rcu_tasks_rude_gp_kthread(void);
 #else
 static inline void show_rcu_tasks_rude_gp_kthread(void) {}
 #endif
-#if !defined(CONFIG_TINY_RCU) && defined(CONFIG_TASKS_TRACE_RCU)
-void show_rcu_tasks_trace_gp_kthread(void);
-#else
-static inline void show_rcu_tasks_trace_gp_kthread(void) {}
-#endif
 
 #ifdef CONFIG_TINY_RCU
 static inline bool rcu_cpu_beenfullyonline(int cpu) { return true; }
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 72619e5e8549dc..5120e1ce811413 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1130,7 +1130,6 @@ static struct rcu_torture_ops tasks_tracing_ops = {
 	.exp_sync	= synchronize_rcu_tasks_trace,
 	.call		= call_rcu_tasks_trace,
 	.cb_barrier	= rcu_barrier_tasks_trace,
-	.gp_kthread_dbg	= show_rcu_tasks_trace_gp_kthread,
 	.get_gp_data    = rcu_tasks_trace_get_gp_data,
 	.cbflood_max	= 50000,
 	.irq_capable	= 1,
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 50f5c483e0e15a..6e2530fe23e620 100644
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -1468,11 +1468,6 @@ void __init rcu_tasks_trace_suppress_unused(void)
 }
 
 #if !defined(CONFIG_TINY_RCU)
-void show_rcu_tasks_trace_gp_kthread(void)
-{
-}
-EXPORT_SYMBOL_GPL(show_rcu_tasks_trace_gp_kthread);
-
 void rcu_tasks_trace_torture_stats_print(char *tt, char *tf)
 {
 }
@@ -1497,7 +1492,6 @@ void show_rcu_tasks_gp_kthreads(void)
 {
 	show_rcu_tasks_classic_gp_kthread();
 	show_rcu_tasks_rude_gp_kthread();
-	show_rcu_tasks_trace_gp_kthread();
 }
 #endif /* #ifndef CONFIG_TINY_RCU */
 
-- 
2.40.1