On Wed, Mar 17, 2021 at 05:48:48PM +0100, Peter Zijlstra wrote:
I think you'll find that if you use ww_mutex_init() it'll all work. Let
me go and zap this patch, and then I'll try and figure out why
DEFINE_WW_MUTEX() is buggered.
Moo, I can't get the compiler to do as I want :/
The below is so close but doesn't actually compile.. Maybe we should
just give up on DEFINE_WW_MUTEX and simply remove it.
---
diff --git a/include/linux/mutex.h b/include/linux/mutex.h
index 0cd631a19727..85f50538f26a 100644
--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -129,12 +129,15 @@ do {
\
# define __DEP_MAP_MUTEX_INITIALIZER(lockname)
#endif
-#define __MUTEX_INITIALIZER(lockname) \
+#define ___MUTEX_INITIALIZER(lockname, depmap) \
{ .owner = ATOMIC_LONG_INIT(0) \
, .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
, .wait_list = LIST_HEAD_INIT(lockname.wait_list) \
__DEBUG_MUTEX_INITIALIZER(lockname) \
- __DEP_MAP_MUTEX_INITIALIZER(lockname) }
+ depmap }
+
+#define __MUTEX_INITIALIZER(lockname) \
+ ___MUTEX_INITIALIZER(lockname,
__DEP_MAP_MUTEX_INITIALIZER(lockname))
#define DEFINE_MUTEX(mutexname) \
struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
diff --git a/include/linux/ww_mutex.h b/include/linux/ww_mutex.h
index 6ecf2a0220db..c62a030652b4 100644
--- a/include/linux/ww_mutex.h
+++ b/include/linux/ww_mutex.h
@@ -50,9 +50,17 @@ struct ww_acquire_ctx {
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# define __WW_CLASS_MUTEX_INITIALIZER(lockname, class) \
- , .ww_class = class
+ , .ww_class = &(class)
+
+# define __DEP_MAP_WW_MUTEX_INITIALIZER(lockname, class) \
+ , .dep_map = { \
+ .key = &(class).mutex_key, \
+ .name = (class).mutex_name, \