rust: sync: Add __rust_helper to helpers

This is needed to inline these helpers into Rust code.

Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20260105-define-rust-helper-v2-20-51da5f454a67@google.com

Author: Darksonn

rust/helpers/mutex.c

@@ -2,28 +2,29 @@
 
 #include <linux/mutex.h>
 
-void rust_helper_mutex_lock(struct mutex *lock)
+__rust_helper void rust_helper_mutex_lock(struct mutex *lock)
 {
 	mutex_lock(lock);
 }
 
-int rust_helper_mutex_trylock(struct mutex *lock)
+__rust_helper int rust_helper_mutex_trylock(struct mutex *lock)
 {
 	return mutex_trylock(lock);
 }
 
-void rust_helper___mutex_init(struct mutex *mutex, const char *name,
-			      struct lock_class_key *key)
+__rust_helper void rust_helper___mutex_init(struct mutex *mutex,
+					    const char *name,
+					    struct lock_class_key *key)
 {
 	__mutex_init(mutex, name, key);
 }
 
-void rust_helper_mutex_assert_is_held(struct mutex *mutex)
+__rust_helper void rust_helper_mutex_assert_is_held(struct mutex *mutex)
 {
 	lockdep_assert_held(mutex);
 }
 
-void rust_helper_mutex_destroy(struct mutex *lock)
+__rust_helper void rust_helper_mutex_destroy(struct mutex *lock)
 {
 	mutex_destroy(lock);
 }

rust/helpers/spinlock.c

@@ -2,8 +2,9 @@
 
 #include <linux/spinlock.h>
 
-void rust_helper___spin_lock_init(spinlock_t *lock, const char *name,
-				  struct lock_class_key *key)
+__rust_helper void rust_helper___spin_lock_init(spinlock_t *lock,
+						const char *name,
+						struct lock_class_key *key)
 {
 #ifdef CONFIG_DEBUG_SPINLOCK
 # if defined(CONFIG_PREEMPT_RT)
@@ -16,22 +17,22 @@ void rust_helper___spin_lock_init(spinlock_t *lock, const char *name,
 #endif /* CONFIG_DEBUG_SPINLOCK */
 }
 
-void rust_helper_spin_lock(spinlock_t *lock)
+__rust_helper void rust_helper_spin_lock(spinlock_t *lock)
 {
 	spin_lock(lock);
 }
 
-void rust_helper_spin_unlock(spinlock_t *lock)
+__rust_helper void rust_helper_spin_unlock(spinlock_t *lock)
 {
 	spin_unlock(lock);
 }
 
-int rust_helper_spin_trylock(spinlock_t *lock)
+__rust_helper int rust_helper_spin_trylock(spinlock_t *lock)
 {
 	return spin_trylock(lock);
 }
 
-void rust_helper_spin_assert_is_held(spinlock_t *lock)
+__rust_helper void rust_helper_spin_assert_is_held(spinlock_t *lock)
 {
 	lockdep_assert_held(lock);
 }

rust/helpers/sync.c

@@ -2,12 +2,12 @@
 
 #include <linux/lockdep.h>
 
-void rust_helper_lockdep_register_key(struct lock_class_key *k)
+__rust_helper void rust_helper_lockdep_register_key(struct lock_class_key *k)
 {
 	lockdep_register_key(k);
 }
 
-void rust_helper_lockdep_unregister_key(struct lock_class_key *k)
+__rust_helper void rust_helper_lockdep_unregister_key(struct lock_class_key *k)
 {
 	lockdep_unregister_key(k);
 }