The following commit has been merged into the core/rcu branch of tip:
Commit-ID: 9ced454807191e44ef093aeeee68194be9ce3a1a
Gitweb: https://git.kernel.org/tip/9ced454807191e44ef093aeeee68194be9ce3a1a
Author: Jules Irenge <jbi.octave@xxxxxxxxx>
AuthorDate: Mon, 20 Jan 2020 22:42:15
Committer: Paul E. McKenney <paulmck@xxxxxxxxxx>
CommitterDate: Thu, 20 Feb 2020 15:58:23 -08:00
rcu: Add missing annotation for rcu_nocb_bypass_lock()
Sparse reports warning at rcu_nocb_bypass_lock()
|warning: context imbalance in rcu_nocb_bypass_lock() - wrong count at exit
To fix this, this commit adds an __acquires(&rdp->nocb_bypass_lock).
Given that rcu_nocb_bypass_lock() does actually call raw_spin_lock()
when raw_spin_trylock() fails, this not only fixes the warning but also
improves on the readability of the code.
Signed-off-by: Jules Irenge <jbi.octave@xxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
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 0f8b714..6db2cad 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1486,6 +1486,7 @@ 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))
|