From: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Date: Tue, 29 Sep 2015 01:19:24 +0000 (-0700)
Subject: rcu: Simplify rcu_sched_qs() control flow
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=fecbf6f01fbd83e6419ccb7f61d9a6eb987f1d92;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

rcu: Simplify rcu_sched_qs() control flow

This commit applies an early-exit approach to rcu_sched_qs(), reducing
the nesting level and saving a line of code.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 23df2661c899..ed3bc0578cc5 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -244,22 +244,21 @@ void rcu_sched_qs(void)
 {
 	unsigned long flags;
 
-	if (__this_cpu_read(rcu_sched_data.cpu_no_qs.s)) {
-		trace_rcu_grace_period(TPS("rcu_sched"),
-				       __this_cpu_read(rcu_sched_data.gpnum),
-				       TPS("cpuqs"));
-		__this_cpu_write(rcu_sched_data.cpu_no_qs.b.norm, false);
-		if (!__this_cpu_read(rcu_sched_data.cpu_no_qs.b.exp))
-			return;
-		local_irq_save(flags);
-		if (__this_cpu_read(rcu_sched_data.cpu_no_qs.b.exp)) {
-			__this_cpu_write(rcu_sched_data.cpu_no_qs.b.exp, false);
-			rcu_report_exp_rdp(&rcu_sched_state,
-					   this_cpu_ptr(&rcu_sched_data),
-					   true);
-		}
-		local_irq_restore(flags);
+	if (!__this_cpu_read(rcu_sched_data.cpu_no_qs.s))
+		return;
+	trace_rcu_grace_period(TPS("rcu_sched"),
+			       __this_cpu_read(rcu_sched_data.gpnum),
+			       TPS("cpuqs"));
+	__this_cpu_write(rcu_sched_data.cpu_no_qs.b.norm, false);
+	if (!__this_cpu_read(rcu_sched_data.cpu_no_qs.b.exp))
+		return;
+	local_irq_save(flags);
+	if (__this_cpu_read(rcu_sched_data.cpu_no_qs.b.exp)) {
+		__this_cpu_write(rcu_sched_data.cpu_no_qs.b.exp, false);
+		rcu_report_exp_rdp(&rcu_sched_state,
+				   this_cpu_ptr(&rcu_sched_data), true);
 	}
+	local_irq_restore(flags);
 }
 
 void rcu_bh_qs(void)