From e4e17af3b7f8841279b5a429de14907e26845c39 Mon Sep 17 00:00:00 2001
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sun, 15 Aug 2021 23:28:20 +0200
Subject: [PATCH] locking/rtmutex: Reduce <linux/rtmutex.h> header
 dependencies, only include <linux/rbtree_types.h>

We have the following header dependency problem on RT:

 - <linux/rtmutex.h> needs the definition of 'struct rb_root_cached'.
 - <linux/rbtree.h> includes <linux/kernel.h>, which includes <linux/spinlock.h>

That works nicely for non-RT enabled kernels, but on RT enabled kernels
spinlocks are based on rtmutexes, which creates another circular header
dependency as <linux/spinlocks.h> will require <linux/rtmutex.h>.

Include <linux/rbtree_types.h> instead.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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/20210815211303.598003167@linutronix.de
---
 include/linux/rtmutex.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/rtmutex.h b/include/linux/rtmutex.h
index 4be97ae..9deedfe 100644
--- a/include/linux/rtmutex.h
+++ b/include/linux/rtmutex.h
@@ -15,7 +15,7 @@
 
 #include <linux/compiler.h>
 #include <linux/linkage.h>
-#include <linux/rbtree.h>
+#include <linux/rbtree_types.h>
 #include <linux/spinlock_types_raw.h>
 
 extern int max_lock_depth; /* for sysctl */
-- 
2.7.4