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. Change-Id: If4975db6c4b8e2e442c6bb0d11900260f424c1ea Signed-off-by: Yaroslav Furman <[email protected]> Signed-off-by: alk3pInjection <[email protected]> Signed-off-by: LibXZR <[email protected]>
realme-mt6781-dev · Apr 15, 2024 · 171d4ce · 171d4ce
1 parent 9eac798
commit 171d4ce
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
@@ -4179,9 +4179,9 @@ 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);
-	rcu_par_gp_wq = alloc_workqueue("rcu_par_gp", WQ_MEM_RECLAIM, 0);
+	rcu_par_gp_wq = alloc_workqueue("rcu_par_gp", WQ_POWER_EFFICIENT | WQ_MEM_RECLAIM, 0);
 	WARN_ON(!rcu_par_gp_wq);
 }