From 17b41842ecf70ea595220b384e6380d29c39b555 Mon Sep 17 00:00:00 2001
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Thu, 11 Jun 2020 22:51:45 +1000
Subject: [PATCH] printk: Make linux/printk.h self-contained

As it stands if you include printk.h it will fail to compile
because it requires definitions from ratelimit.h.  However, simply
including ratelimit.h from printk.h does not work due to inclusion
loops involving sched.h and kernel.h.

This patch solves this by moving bits from ratelimit.h into a new
header file which can then be included by printk.h without any
worries about header loops.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 include/linux/printk.h          |  1 +
 include/linux/ratelimit.h       | 36 +--------------------------
 include/linux/ratelimit_types.h | 43 +++++++++++++++++++++++++++++++++
 3 files changed, 45 insertions(+), 35 deletions(-)
 create mode 100644 include/linux/ratelimit_types.h

diff --git a/include/linux/printk.h b/include/linux/printk.h
index fc8f03c5454302..34c1a7be3e014f 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -7,6 +7,7 @@
 #include <linux/kern_levels.h>
 #include <linux/linkage.h>
 #include <linux/cache.h>
+#include <linux/ratelimit_types.h>
 
 extern const char linux_banner[];
 extern const char linux_proc_banner[];
diff --git a/include/linux/ratelimit.h b/include/linux/ratelimit.h
index 8ddf79e9207a9d..b17e0cd0a30cfb 100644
--- a/include/linux/ratelimit.h
+++ b/include/linux/ratelimit.h
@@ -2,41 +2,10 @@
 #ifndef _LINUX_RATELIMIT_H
 #define _LINUX_RATELIMIT_H
 
-#include <linux/param.h>
+#include <linux/ratelimit_types.h>
 #include <linux/sched.h>
 #include <linux/spinlock.h>
 
-#define DEFAULT_RATELIMIT_INTERVAL	(5 * HZ)
-#define DEFAULT_RATELIMIT_BURST		10
-
-/* issue num suppressed message on exit */
-#define RATELIMIT_MSG_ON_RELEASE	BIT(0)
-
-struct ratelimit_state {
-	raw_spinlock_t	lock;		/* protect the state */
-
-	int		interval;
-	int		burst;
-	int		printed;
-	int		missed;
-	unsigned long	begin;
-	unsigned long	flags;
-};
-
-#define RATELIMIT_STATE_INIT(name, interval_init, burst_init) {		\
-		.lock		= __RAW_SPIN_LOCK_UNLOCKED(name.lock),	\
-		.interval	= interval_init,			\
-		.burst		= burst_init,				\
-	}
-
-#define RATELIMIT_STATE_INIT_DISABLED					\
-	RATELIMIT_STATE_INIT(ratelimit_state, 0, DEFAULT_RATELIMIT_BURST)
-
-#define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init)		\
-									\
-	struct ratelimit_state name =					\
-		RATELIMIT_STATE_INIT(name, interval_init, burst_init)	\
-
 static inline void ratelimit_state_init(struct ratelimit_state *rs,
 					int interval, int burst)
 {
@@ -73,9 +42,6 @@ ratelimit_set_flags(struct ratelimit_state *rs, unsigned long flags)
 
 extern struct ratelimit_state printk_ratelimit_state;
 
-extern int ___ratelimit(struct ratelimit_state *rs, const char *func);
-#define __ratelimit(state) ___ratelimit(state, __func__)
-
 #ifdef CONFIG_PRINTK
 
 #define WARN_ON_RATELIMIT(condition, state)	({		\
diff --git a/include/linux/ratelimit_types.h b/include/linux/ratelimit_types.h
new file mode 100644
index 00000000000000..b676aa419eef87
--- /dev/null
+++ b/include/linux/ratelimit_types.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_RATELIMIT_TYPES_H
+#define _LINUX_RATELIMIT_TYPES_H
+
+#include <linux/bits.h>
+#include <linux/param.h>
+#include <linux/spinlock_types.h>
+
+#define DEFAULT_RATELIMIT_INTERVAL	(5 * HZ)
+#define DEFAULT_RATELIMIT_BURST		10
+
+/* issue num suppressed message on exit */
+#define RATELIMIT_MSG_ON_RELEASE	BIT(0)
+
+struct ratelimit_state {
+	raw_spinlock_t	lock;		/* protect the state */
+
+	int		interval;
+	int		burst;
+	int		printed;
+	int		missed;
+	unsigned long	begin;
+	unsigned long	flags;
+};
+
+#define RATELIMIT_STATE_INIT(name, interval_init, burst_init) {		\
+		.lock		= __RAW_SPIN_LOCK_UNLOCKED(name.lock),	\
+		.interval	= interval_init,			\
+		.burst		= burst_init,				\
+	}
+
+#define RATELIMIT_STATE_INIT_DISABLED					\
+	RATELIMIT_STATE_INIT(ratelimit_state, 0, DEFAULT_RATELIMIT_BURST)
+
+#define DEFINE_RATELIMIT_STATE(name, interval_init, burst_init)		\
+									\
+	struct ratelimit_state name =					\
+		RATELIMIT_STATE_INIT(name, interval_init, burst_init)	\
+
+extern int ___ratelimit(struct ratelimit_state *rs, const char *func);
+#define __ratelimit(state) ___ratelimit(state, __func__)
+
+#endif /* _LINUX_RATELIMIT_TYPES_H */