Re: [PATCH v5 02/10] locking/mutex: introduce devm_mutex_init

From: George Stark
Date: Tue Mar 12 2024 - 11:31:13 EST


Hello Christophe

On 3/12/24 14:51, Christophe Leroy wrote:


Le 12/03/2024 à 12:39, George Stark a écrit :
[Vous ne recevez pas souvent de courriers de gnstark@xxxxxxxxxxxxxxxxx.
Découvrez pourquoi ceci est important à
https://aka.ms/LearnAboutSenderIdentification ]

..

You don't need that inline function, just change debug_devm_mutex_init()
to __devm_mutex_init().

I stuck to debug_* name because mutex-debug.c already exports a set
of debug_ calls so...
Well it's not essential anyway. Here's the next try:

diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index 67edc4ca2bee..537b5ea18ceb 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -22,6 +22,8 @@
#include <linux/cleanup.h>
#include <linux/mutex_types.h>

+struct device;
+
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \
, .dep_map = { \
@@ -117,6 +119,29 @@ do { \
} while (0)
#endif /* CONFIG_PREEMPT_RT */

+#ifdef CONFIG_DEBUG_MUTEXES
+
+int __devm_mutex_init(struct device *dev, struct mutex *lock);
+
+#else
+
+static inline int __devm_mutex_init(struct device *dev, struct mutex *lock)
+{
+ /*
+ * When CONFIG_DEBUG_MUTEXES is off mutex_destroy is just a nop so
+ * no really need to register it in devm subsystem.
+ */
+ return 0;
+}
+
+#endif
+
+#define devm_mutex_init(dev, mutex) \
+({ \
+ mutex_init(mutex); \
+ __devm_mutex_init(dev, mutex); \
+})
+
/*
* See kernel/locking/mutex.c for detailed documentation of these APIs.
* Also see Documentation/locking/mutex-design.rst.
diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c
index bc8abb8549d2..6aa77e3dc82e 100644
--- a/kernel/locking/mutex-debug.c
+++ b/kernel/locking/mutex-debug.c
@@ -19,6 +19,7 @@
#include <linux/kallsyms.h>
#include <linux/interrupt.h>
#include <linux/debug_locks.h>
+#include <linux/device.h>

#include "mutex.h"

@@ -89,6 +90,16 @@ void debug_mutex_init(struct mutex *lock, const char *name,
lock->magic = lock;
}

+static void devm_mutex_release(void *res)
+{
+ mutex_destroy(res);
+}
+
+int __devm_mutex_init(struct device *dev, struct mutex *lock)
+{
+ return devm_add_action_or_reset(dev, devm_mutex_release, lock);
+}
+
/***
* mutex_destroy - mark a mutex unusable
* @lock: the mutex to be destroyed
--
2.25.1



+
+#else
+
+static inline int __devm_mutex_init(struct device *dev, struct mutex
*lock)
+{
+       /*
+       * When CONFIG_DEBUG_MUTEXES is off mutex_destroy is just a nop so
+       * no really need to register it in devm subsystem.
+       */

Don't know if it is because tabs are replaced by blanks in you email,
but the stars should be aligned

Ack


--
Best regards
George