[RFC PATCH] sched: let task migration destination cpu do active balance

[Alex Shi]

Chris Redpath found an issue on active balance: 
We let the task source cpu, the busiest cpu, do the active balance,
while the destination cpu maybe idle. thus we take the busiest cpu
time, but left the idlest cpu wait. That is not good for performance.

This patch let the destination cpu do active balance. It will give tasks
more running time.

Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxx>
---
 kernel/sched/fair.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 9b4c4f3..cccee76 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6308,7 +6308,7 @@ more_balance:
 			raw_spin_unlock_irqrestore(&busiest->lock, flags);
 
 			if (active_balance) {
-				stop_one_cpu_nowait(cpu_of(busiest),
+				stop_one_cpu_nowait(busiest->push_cpu,
 					active_load_balance_cpu_stop, busiest,
 					&busiest->active_balance_work);
 			}
-- 
1.8.1.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/