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>
diff --git a/include/linux/preempt.h b/include/linux/preempt.h
index 58969b2..5a710b9 100644
--- a/include/linux/preempt.h
+++ b/include/linux/preempt.h
@@ -48,12 +48,14 @@
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 @@
#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)