sched: fix SMP migration latencies
fix SMP migration latencies: the vruntimes of different CPUs are
at incompatible offsets so they have to be fixed up when migrating
a task across CPUs.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/sched.c b/kernel/sched.c
index 0f0cf37..4ad789d 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -992,6 +992,9 @@
if (p->se.block_start)
p->se.block_start -= clock_offset;
#endif
+ if (likely(new_rq->cfs.min_vruntime))
+ p->se.vruntime -= old_rq->cfs.min_vruntime -
+ new_rq->cfs.min_vruntime;
__set_task_cpu(p, new_cpu);
}