From: Andrew Morton <akpm@linux-foundation.org>

In file included from kernel/exit.c:48:
include/linux/freezer.h:10: error: redefinition of 'frozen'
include/linux/freezer.h:10: error: previous definition of 'frozen' was here
include/linux/freezer.h:18: error: redefinition of 'freezing'
include/linux/freezer.h:18: error: previous definition of 'freezing' was here
include/linux/freezer.h:26: error: redefinition of 'set_freeze_flag'
include/linux/freezer.h:26: error: previous definition of 'set_freeze_flag' was here
include/linux/freezer.h:34: error: redefinition of 'clear_freeze_flag'
include/linux/freezer.h:34: error: previous definition of 'clear_freeze_flag' was here
include/linux/freezer.h:48: error: redefinition of 'thaw_process'
include/linux/freezer.h:48: error: previous definition of 'thaw_process' was here
include/linux/freezer.h:66: error: redefinition of 'try_to_freeze'
include/linux/freezer.h:66: error: previous definition of 'try_to_freeze' was here
include/linux/freezer.h:93: error: redefinition of 'freezer_do_not_count'
include/linux/freezer.h:93: error: previous definition of 'freezer_do_not_count' was here
include/linux/freezer.h:103: error: redefinition of 'freezer_count'
include/linux/freezer.h:103: error: previous definition of 'freezer_count' was here
include/linux/freezer.h:114: error: redefinition of 'freezer_should_skip'
include/linux/freezer.h:114: error: previous definition of 'freezer_should_skip' was here
include/linux/freezer.h:122: error: redefinition of 'set_freezable'
include/linux/freezer.h:122: error: previous definition of 'set_freezable' was here

It's included in some header file, it needs include protection.

Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/freezer.h |    5 +++++
 1 file changed, 5 insertions(+)

diff -puN include/linux/freezer.h~freezer-make-kernel-threads-nonfreezable-by-default-fix-fix include/linux/freezer.h
--- a/include/linux/freezer.h~freezer-make-kernel-threads-nonfreezable-by-default-fix-fix
+++ a/include/linux/freezer.h
@@ -1,5 +1,8 @@
 /* Freezer declarations */
 
+#ifndef FREEZER_H_INCLUDED
+#define FREEZER_H_INCLUDED
+
 #include <linux/sched.h>
 
 #ifdef CONFIG_PM
@@ -140,3 +143,5 @@ static inline void freezer_count(void) {
 static inline int freezer_should_skip(struct task_struct *p) { return 0; }
 static inline void set_freezable(void) {}
 #endif
+
+#endif	/* FREEZER_H_INCLUDED */
_