[PATCH 3/9] workqueue: introduce `__INIT_WORK_WITH_KEY`

[Alice Ryhl <aliceryhl@google.com>]

From: Wedson Almeida Filho <walmeida@microsoft.com>

A Rust helper (introduced in a later patch) needs to call
`__INIT_WORK` with a passed key, rather than define one in place.

In order to do that, this moves the initialization code from
the `__INIT_WORK` macro into a new `__INIT_WORK_WITH_KEY` macro
which takes the key as an extra parameter.

Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com>
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Co-developed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
---
Taken from [1]. Wedson's email updated at Wedson's request. Tejun's
Acked-by taken from [2].

[1]: https://lore.kernel.org/rust-for-linux/20220802015052.10452-7-ojeda@kernel.org/
[2]: https://lore.kernel.org/rust-for-linux/Yvq3IfK4+C94AeE2@slm.duckdns.org/

 include/linux/workqueue.h | 31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 3992c994787f..c91a84a4723d 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -221,24 +221,31 @@ static inline unsigned int work_static(struct work_struct *work) { return 0; }
  * to generate better code.
  */
 #ifdef CONFIG_LOCKDEP
+#define __INIT_WORK_WITH_KEY(_work, _func, _onstack, _key)		\
+	do {								\
+		__init_work((_work), _onstack);				\
+		(_work)->data = (atomic_long_t) WORK_DATA_INIT();	\
+		lockdep_init_map(&(_work)->lockdep_map, "(work_completion)"#_work, _key, 0); \
+		INIT_LIST_HEAD(&(_work)->entry);			\
+		(_work)->func = (_func);				\
+	} while (0)
+
 #define __INIT_WORK(_work, _func, _onstack)				\
 	do {								\
 		static struct lock_class_key __key;			\
-									\
-		__init_work((_work), _onstack);				\
-		(_work)->data = (atomic_long_t) WORK_DATA_INIT();	\
-		lockdep_init_map(&(_work)->lockdep_map, "(work_completion)"#_work, &__key, 0); \
-		INIT_LIST_HEAD(&(_work)->entry);			\
-		(_work)->func = (_func);				\
+		__INIT_WORK_WITH_KEY(_work, _func, _onstack, &__key);	\
 	} while (0)
 #else
+#define __INIT_WORK_WITH_KEY(_work, _func, _onstack, _key)		\
+	do {								\
+		__init_work((_work), _onstack);				\
+		(_work)->data = (atomic_long_t) WORK_DATA_INIT();	\
+		INIT_LIST_HEAD(&(_work)->entry);			\
+		(_work)->func = (_func);				\
+	} while (0)
+
 #define __INIT_WORK(_work, _func, _onstack)				\
-	do {								\
-		__init_work((_work), _onstack);				\
-		(_work)->data = (atomic_long_t) WORK_DATA_INIT();	\
-		INIT_LIST_HEAD(&(_work)->entry);			\
-		(_work)->func = (_func);				\
-	} while (0)
+	__INIT_WORK_WITH_KEY(_work, _func, _onstack, NULL)
 #endif
 
 #define INIT_WORK(_work, _func)						\
-- 
2.41.0.255.g8b1d071c50-goog