From 6bc8996add9f82d0153b0be44efe282bd45dc702 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 15 Aug 2021 23:28:02 +0200
Subject: [PATCH] locking/rtmutex: Provide rt_mutex_base_is_locked()
Git-commit: 6bc8996add9f82d0153b0be44efe282bd45dc702
Patch-mainline: v5.15-rc1
References: bsc#1190137 bsc#1189998

Provide rt_mutex_base_is_locked(), which will be used for various wrapped
locking primitives for RT.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211302.899572818@linutronix.de
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>

---
 include/linux/rtmutex.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h
index 852740285d71..174419ee58e9 100644
--- a/include/linux/rtmutex.h
+++ b/include/linux/rtmutex.h
@@ -13,6 +13,7 @@
 #ifndef __LINUX_RT_MUTEX_H
 #define __LINUX_RT_MUTEX_H
 
+#include <linux/compiler.h>
 #include <linux/linkage.h>
 #include <linux/rbtree.h>
 #include <linux/spinlock_types.h>
@@ -32,6 +33,17 @@ struct rt_mutex_base {
 	.owner = NULL							\
 }
 
+/**
+ * rt_mutex_base_is_locked - is the rtmutex locked
+ * @lock: the mutex to be queried
+ *
+ * Returns true if the mutex is locked, false if unlocked.
+ */
+static inline bool rt_mutex_base_is_locked(struct rt_mutex_base *lock)
+{
+	return READ_ONCE(lock->owner) != NULL;
+}
+
 extern void rt_mutex_base_init(struct rt_mutex_base *rtb);
 
 /**
-- 
2.26.2