rcu: fix a performance regression

Commit "rcu: Create RCU-specific workqueues with rescuers" switched RCU
to using local workqueses and removed power efficiency flag from them.

This caused a performance regression that can be observed in Geekbench 5
after enabling CONFIG_WQ_POWER_EFFICIENT_DEFAULT: score went down from
760/2500 to 620/2300 (single/multi core respectively).

Add WQ_POWER_EFFICIENT flag to avoid this regression.

Signed-off-by: Yaroslav Furman <yaro330@gmail.com>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>
This commit is contained in:
Yaroslav Furman
2019-12-11 03:06:26 +03:00
committed by Pranav Vashi
parent 9176df89d4
commit 2c73901cf7

View File

@@ -4240,7 +4240,7 @@ void __init rcu_init(void)
}
/* Create workqueue for expedited GPs and for Tree SRCU. */
rcu_gp_wq = alloc_workqueue("rcu_gp", WQ_MEM_RECLAIM, 0);
rcu_gp_wq = alloc_workqueue("rcu_gp", WQ_POWER_EFFICIENT | WQ_MEM_RECLAIM, 0);
WARN_ON(!rcu_gp_wq);
}