[PATCH 4/5] rcu: Add missing annotation for rcu_nocb_bypass_lock()

[Jules Irenge]

Sparse reports warning at rcu_nocb_bypass_lock()

|warning: context imbalance in rcu_nocb_bypass_lock() - wrong count at exit

To fix this, an __acquires(&rdp->nocb_bypass_lock) is added.
Given that rcu_nocb_bypass_lock() does actually
call raw_spin_lock(&rdp->nocb_bypass_lock)
in case raw_spin_trylock(&rdp->nocb_bypass_lock) fails.
This not only fixes the warning
but also improves on the readability of the code.

Signed-off-by: Jules Irenge <jbi.octave@xxxxxxxxx>
---
 kernel/rcu/tree_plugin.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index fa08d55f7040..7689e649b674 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1510,6 +1510,7 @@ module_param(nocb_nobypass_lim_per_jiffy, int, 0);
  * flag the contention.
  */
 static void rcu_nocb_bypass_lock(struct rcu_data *rdp)
+	__acquires(&rdp->nocb_bypass_lock)
 {
 	lockdep_assert_irqs_disabled();
 	if (raw_spin_trylock(&rdp->nocb_bypass_lock))
-- 
2.24.1