sched: introduce se->vruntime
introduce se->vruntime as a sum of weighted delta-exec's, and use that
as the key into the tree.
the idea to use absolute virtual time as the basic metric of scheduling
has been first raised by William Lee Irwin, advanced by Tong Li and first
prototyped by Roman Zippel in the "Really Fair Scheduler" (RFS) patchset.
also see:
http://lkml.org/lkml/2007/9/2/76
for a simpler variant of this patch.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 3c38a50..5e5c457 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -902,6 +902,7 @@
u64 exec_start;
u64 sum_exec_runtime;
+ u64 vruntime;
u64 prev_sum_exec_runtime;
u64 wait_start_fair;
u64 sleep_start_fair;