[PATCH 1/2] preempt: Provide preempt_*_(no)rt variants

[Mel Gorman]

From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

RT needs a few preempt_disable/enable points which are not necessary
otherwise. Implement variants to avoid #ifdeffery.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
---
 include/linux/preempt.h | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/include/linux/preempt.h b/include/linux/preempt.h
index 9881eac0698f..3434f4618178 100644
--- a/include/linux/preempt.h
+++ b/include/linux/preempt.h
@@ -184,7 +184,11 @@ do { \
 	preempt_count_dec(); \
 } while (0)
 
-#define preempt_enable_no_resched() sched_preempt_enable_no_resched()
+#ifdef CONFIG_PREEMPT_RT
+# define preempt_enable_no_resched() sched_preempt_enable_no_resched()
+#else
+# define preempt_enable_no_resched() preempt_enable()
+#endif
 
 #define preemptible()	(preempt_count() == 0 && !irqs_disabled())
 
@@ -278,6 +282,18 @@ do { \
 		set_preempt_need_resched(); \
 } while (0)
 
+#ifdef CONFIG_PREEMPT_RT
+# define preempt_disable_rt()		preempt_disable()
+# define preempt_enable_rt()		preempt_enable()
+# define preempt_disable_nort()		barrier()
+# define preempt_enable_nort()		barrier()
+#else
+# define preempt_disable_rt()		barrier()
+# define preempt_enable_rt()		barrier()
+# define preempt_disable_nort()		preempt_disable()
+# define preempt_enable_nort()		preempt_enable()
+#endif
+
 #ifdef CONFIG_PREEMPT_NOTIFIERS
 
 struct preempt_notifier;
-- 
2.26.2