From: Paul E. McKenney <paulmck@kernel.org>
Date: Wed, 5 Nov 2025 20:32:11 +0000 (-0800)
Subject: rcu: Mark diagnostic functions as notrace
X-Git-Url: https://gentwo.org/gitweb/?a=commitdiff_plain;h=3ed04e3f0362351a57cb3eda1c504506f2df82b1;p=linux%2F.git

rcu: Mark diagnostic functions as notrace

The rcu_lockdep_current_cpu_online(), rcu_read_lock_sched_held(),
rcu_read_lock_held(), rcu_read_lock_bh_held(), rcu_read_lock_any_held()
are used by tracing-related code paths, so putting traces on them is
unlikely to make anyone happy.  This commit therefore marks them all
"notrace".

Reported-by: Leon Hwang <leon.hwang@linux.dev>
Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
---

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 8293bae1dec1..4937adc0a4f4 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -4021,7 +4021,7 @@ bool rcu_cpu_online(int cpu)
  * RCU on an offline processor during initial boot, hence the check for
  * rcu_scheduler_fully_active.
  */
-bool rcu_lockdep_current_cpu_online(void)
+bool notrace rcu_lockdep_current_cpu_online(void)
 {
 	struct rcu_data *rdp;
 	bool ret = false;
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index c912b594ba98..dfeba9b35395 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -117,7 +117,7 @@ static bool rcu_read_lock_held_common(bool *ret)
 	return false;
 }
 
-int rcu_read_lock_sched_held(void)
+int notrace rcu_read_lock_sched_held(void)
 {
 	bool ret;
 
@@ -342,7 +342,7 @@ EXPORT_SYMBOL_GPL(debug_lockdep_rcu_enabled);
  * Note that rcu_read_lock() is disallowed if the CPU is either idle or
  * offline from an RCU perspective, so check for those as well.
  */
-int rcu_read_lock_held(void)
+int notrace rcu_read_lock_held(void)
 {
 	bool ret;
 
@@ -367,7 +367,7 @@ EXPORT_SYMBOL_GPL(rcu_read_lock_held);
  * Note that rcu_read_lock_bh() is disallowed if the CPU is either idle or
  * offline from an RCU perspective, so check for those as well.
  */
-int rcu_read_lock_bh_held(void)
+int notrace rcu_read_lock_bh_held(void)
 {
 	bool ret;
 
@@ -377,7 +377,7 @@ int rcu_read_lock_bh_held(void)
 }
 EXPORT_SYMBOL_GPL(rcu_read_lock_bh_held);
 
-int rcu_read_lock_any_held(void)
+int notrace rcu_read_lock_any_held(void)
 {
 	bool ret;