sched: fix load scaling in group balancing
doing the load balance will change cfs_rq->load.weight (that's the whole point)
but since that's part of the scale factor, we'll scale back with a different
amount.
Weight getting smaller would result in an inflated moved_load which causes
it to stop balancing too soon.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 865cb53a..734e4c5 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1444,6 +1444,8 @@
list_for_each_entry(tg, &task_groups, list) {
struct cfs_rq *busiest_cfs_rq = tg->cfs_rq[busiest_cpu];
+ unsigned long busiest_h_load = busiest_cfs_rq->h_load;
+ unsigned long busiest_weight = busiest_cfs_rq->load.weight;
long rem_load, moved_load;
/*
@@ -1452,8 +1454,8 @@
if (!busiest_cfs_rq->task_weight)
continue;
- rem_load = rem_load_move * busiest_cfs_rq->load.weight;
- rem_load /= busiest_cfs_rq->h_load + 1;
+ rem_load = rem_load_move * busiest_weight;
+ rem_load /= busiest_h_load + 1;
moved_load = __load_balance_fair(this_rq, this_cpu, busiest,
rem_load, sd, idle, all_pinned, this_best_prio,
@@ -1462,8 +1464,8 @@
if (!moved_load)
continue;
- moved_load *= busiest_cfs_rq->h_load;
- moved_load /= busiest_cfs_rq->load.weight + 1;
+ moved_load *= busiest_h_load;
+ moved_load /= busiest_weight + 1;
rem_load_move -= moved_load;
if (rem_load_move < 0)