locking/ww_mutex: Abstract out mutex types

Some ww_mutex helper functions use pointers for the underlying mutex and
mutex_waiter. The upcoming rtmutex based implementation needs to share
these functions. Add and use defines for the types and replace the direct
types in the affected functions.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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/20210815211304.678720245@linutronix.de

kernel/locking/ww_mutex.h

 /* SPDX-License-Identifier: GPL-2.0-only */
 
+#define MUTEX		mutex
+#define MUTEX_WAITER	mutex_waiter
+
 static inline struct mutex_waiter *
 __ww_waiter_first(struct mutex *lock)
 {
@@ -143,7 +146,7 @@ __ww_ctx_stamp_after(struct ww_acquire_ctx *a, struct ww_acquire_ctx *b)
  * __ww_mutex_check_kill() wake any but the earliest context.
  */
 static bool
-__ww_mutex_die(struct mutex *lock, struct mutex_waiter *waiter,
+__ww_mutex_die(struct MUTEX *lock, struct MUTEX_WAITER *waiter,
 	       struct ww_acquire_ctx *ww_ctx)
 {
 	if (!ww_ctx->is_wait_die)
@@ -165,7 +168,7 @@ __ww_mutex_die(struct mutex *lock, struct mutex_waiter *waiter,
  * the lock holders. Even if multiple waiters may wound the lock holder,
  * it's sufficient that only one does.
  */
-static bool __ww_mutex_wound(struct mutex *lock,
+static bool __ww_mutex_wound(struct MUTEX *lock,
 			     struct ww_acquire_ctx *ww_ctx,
 			     struct ww_acquire_ctx *hold_ctx)
 {
@@ -220,9 +223,9 @@ static bool __ww_mutex_wound(struct mutex *lock,
  * The current task must not be on the wait list.
  */
 static void
-__ww_mutex_check_waiters(struct mutex *lock, struct ww_acquire_ctx *ww_ctx)
+__ww_mutex_check_waiters(struct MUTEX *lock, struct ww_acquire_ctx *ww_ctx)
 {
-	struct mutex_waiter *cur;
+	struct MUTEX_WAITER *cur;
 
 	lockdep_assert_held(&lock->wait_lock);
 
@@ -278,7 +281,7 @@ ww_mutex_set_context_fastpath(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
 }
 
 static __always_inline int
-__ww_mutex_kill(struct mutex *lock, struct ww_acquire_ctx *ww_ctx)
+__ww_mutex_kill(struct MUTEX *lock, struct ww_acquire_ctx *ww_ctx)
 {
 	if (ww_ctx->acquired > 0) {
 #ifdef CONFIG_DEBUG_MUTEXES
@@ -306,12 +309,12 @@ __ww_mutex_kill(struct mutex *lock, struct ww_acquire_ctx *ww_ctx)
  * look at waiters before us in the wait-list.
  */
 static inline int
-__ww_mutex_check_kill(struct mutex *lock, struct mutex_waiter *waiter,
+__ww_mutex_check_kill(struct MUTEX *lock, struct MUTEX_WAITER *waiter,
 		      struct ww_acquire_ctx *ctx)
 {
 	struct ww_mutex *ww = container_of(lock, struct ww_mutex, base);
 	struct ww_acquire_ctx *hold_ctx = READ_ONCE(ww->ctx);
-	struct mutex_waiter *cur;
+	struct MUTEX_WAITER *cur;
 
 	if (ctx->acquired == 0)
 		return 0;
@@ -354,11 +357,11 @@ __ww_mutex_check_kill(struct mutex *lock, struct mutex_waiter *waiter,
  * Wound-Wait ensure we wound the owning context when it is younger.
  */
 static inline int
-__ww_mutex_add_waiter(struct mutex_waiter *waiter,
-		      struct mutex *lock,
+__ww_mutex_add_waiter(struct MUTEX_WAITER *waiter,
+		      struct MUTEX *lock,
 		      struct ww_acquire_ctx *ww_ctx)
 {
-	struct mutex_waiter *cur, *pos = NULL;
+	struct MUTEX_WAITER *cur, *pos = NULL;
 	bool is_wait_die;
 
 	if (!ww_ctx) {