sched/rt: Document scheduler related skip-resched-check sites

Create a distinction between scheduler related preempt_enable_no_resched()
calls and the nearly one hundred other places in the kernel that do not
want to reschedule, for one reason or another.

This distinction matters for -rt, where the scheduler and the non-scheduler
preempt models (and checks) are different. For upstream it's purely
documentational.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/n/tip-gs88fvx2mdv5psnzxnv575ke@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 1 deletions

diff --git a/include/linux/preempt.h b/include/linux/preempt.h
index 58969b2a8a8..5a710b9c578 100644
--- a/include/linux/preempt.h
+++ b/include/linux/preempt.h
@@ -48,12 +48,14 @@ do { \
         barrier(); \
 } while (0)
 
-#define preempt_enable_no_resched() \
+#define sched_preempt_enable_no_resched() \
 do { \
         barrier(); \
         dec_preempt_count(); \
 } while (0)
 
+#define preempt_enable_no_resched()     sched_preempt_enable_no_resched()
+
 #define preempt_enable() \
 do { \
         preempt_enable_no_resched(); \
@@ -92,6 +94,7 @@ do { \
 #else /* !CONFIG_PREEMPT_COUNT */
 
 #define preempt_disable()               do { } while (0)
+#define sched_preempt_enable_no_resched()       do { } while (0)
 #define preempt_enable_no_resched()     do { } while (0)
 #define preempt_enable()                do { } while (0)