locking/rtmutex: Add mutex variant for RT
Add the necessary defines, helpers and API functions for replacing struct mutex on
a PREEMPT_RT enabled kernel with an rtmutex based variant.
No functional change when CONFIG_PREEMPT_RT=n
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/20210815211305.081517417@linutronix.de
diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c
index 9906ca6..3a65bf4 100644
--- a/kernel/locking/mutex.c
+++ b/kernel/locking/mutex.c
@@ -30,6 +30,7 @@
#include <linux/debug_locks.h>
#include <linux/osq_lock.h>
+#ifndef CONFIG_PREEMPT_RT
#include "mutex.h"
#ifdef CONFIG_DEBUG_MUTEXES
@@ -1066,7 +1067,8 @@ ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ctx)
}
EXPORT_SYMBOL(ww_mutex_lock_interruptible);
-#endif
+#endif /* !CONFIG_DEBUG_LOCK_ALLOC */
+#endif /* !CONFIG_PREEMPT_RT */
/**
* atomic_dec_and_mutex_lock - return holding mutex if we dec to 0