Even if it's not critical, the avoidance of checking the error code
from devm_mutex_init() call today diminishes the point of using devm
variant of it. Tomorrow it may even leak something. Enforce all callers
checking the return value through the compiler.
As devm_mutex_init() itself is a macro, it can not be annotated
directly. Annotate __devm_mutex_init() instead.
Unfortunately __must_check/warn_unused_result don't propagate through
statement expression. So move the statement expression into the argument
list of the call to __devm_mutex_init() through a helper macro.
Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
---
include/linux/mutex.h | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index 2bf91b57591b49e4668752e773419ae945f124da..970b0526c549b699e7e4e1ba522696537957e069 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -126,11 +126,11 @@ do { \
#ifdef CONFIG_DEBUG_MUTEXES
-int __devm_mutex_init(struct device *dev, struct mutex *lock);
+int __must_check __devm_mutex_init(struct device *dev, struct mutex *lock);
#else
-static inline int __devm_mutex_init(struct device *dev, struct mutex *lock)
+static inline int __must_check __devm_mutex_init(struct device *dev, struct mutex *lock)
{
/*
* When CONFIG_DEBUG_MUTEXES is off mutex_destroy() is just a nop so
@@ -141,14 +141,17 @@ static inline int __devm_mutex_init(struct device *dev, struct mutex *lock)
#endif
-#define devm_mutex_init(dev, mutex) \
+#define __mutex_init_ret(mutex) \
({ \
typeof(mutex) mutex_ = (mutex); \
\
mutex_init(mutex_); \
- __devm_mutex_init(dev, mutex_); \
+ mutex_; \
})
+#define devm_mutex_init(dev, mutex) \
+ __devm_mutex_init(dev, __mutex_init_ret(mutex))
+
/*
* See kernel/locking/mutex.c for detailed documentation of these APIs.
* Also see Documentation/locking/mutex-design.rst.
--
2.48.1
