sched/fair: Simplify the code of should_we_balance() (64297f2b) · Commits · 戴 / test

We only consider group_balance_cpu() after there is no idle cpu. So, just do comparison before return at these two cases. Signed-off-by:

kernel/sched/fair.c

+5 −11

Original line number	Diff line number	Diff line
		@@ -9413,7 +9413,7 @@ static int active_load_balance_cpu_stop(void *data);
		static int should_we_balance(struct lb_env *env)
		{
		struct sched_group *sg = env->sd->groups;
		int cpu, balance_cpu = -1;
		int cpu;

		/*
		* Ensure the balancing environment is consistent; can happen
		@@ -9434,18 +9434,12 @@ static int should_we_balance(struct lb_env *env)
		if (!idle_cpu(cpu))
		continue;

		balance_cpu = cpu;
		break;
		/* Are we the first idle CPU? */
		return cpu == env->dst_cpu;
		}

		if (balance_cpu == -1)
		balance_cpu = group_balance_cpu(sg);

		/*
		* First idle CPU or the first CPU(busiest) in this sched group
		* is eligible for doing load balancing at this and above domains.
		*/
		return balance_cpu == env->dst_cpu;
		/* Are we the first CPU of this group ? */
		return group_balance_cpu(sg) == env->dst_cpu;
		}

		/*