Commit 3f5ad914 authored by YueHaibing's avatar YueHaibing Committed by Ingo Molnar
Browse files

sched/fair: Move update_nohz_stats() to the CONFIG_NO_HZ_COMMON block to... 


sched/fair: Move update_nohz_stats() to the CONFIG_NO_HZ_COMMON block to simplify the code & fix an unused function warning

When !CONFIG_NO_HZ_COMMON we get this new GCC warning:

   kernel/sched/fair.c:8398:13: warning: ‘update_nohz_stats’ defined but not used [-Wunused-function]

Move update_nohz_stats() to an already existing CONFIG_NO_HZ_COMMON #ifdef
block.

Beyond fixing the GCC warning, this also simplifies the update_nohz_stats() function.

[ mingo: Rewrote the changelog. ]

Fixes: 0826530d ("sched/fair: Remove update of blocked load from newidle_balance")
Signed-off-by: default avatarYueHaibing <yuehaibing@huawei.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Reviewed-by: default avatarVincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20210329144029.29200-1-yuehaibing@huawei.com
parent d0d252b8

kernel/sched/fair.c

+18 −22
Original line number Diff line number Diff line
@@ -8430,28 +8430,6 @@ group_type group_classify(unsigned int imbalance_pct, 
	return group_has_spare;

}



static bool update_nohz_stats(struct rq *rq)

{

#ifdef CONFIG_NO_HZ_COMMON

	unsigned int cpu = rq->cpu;



	if (!rq->has_blocked_load)

		return false;



	if (!cpumask_test_cpu(cpu, nohz.idle_cpus_mask))

		return false;



	if (!time_after(jiffies, READ_ONCE(rq->last_blocked_load_update_tick)))

		return true;



	update_blocked_averages(cpu);



	return rq->has_blocked_load;

#else

	return false;

#endif

}



/**

 * update_sg_lb_stats - Update sched_group's statistics for load balancing.

 * @env: The load balancing environment.
@@ -10406,6 +10384,24 @@ void nohz_balance_enter_idle(int cpu) 
	WRITE_ONCE(nohz.has_blocked, 1);

}



static bool update_nohz_stats(struct rq *rq)

{

	unsigned int cpu = rq->cpu;



	if (!rq->has_blocked_load)

		return false;



	if (!cpumask_test_cpu(cpu, nohz.idle_cpus_mask))

		return false;



	if (!time_after(jiffies, READ_ONCE(rq->last_blocked_load_update_tick)))

		return true;



	update_blocked_averages(cpu);



	return rq->has_blocked_load;

}



/*

 * Internal function that runs load balance for all idle cpus. The load balance

 * can be a simple update of blocked load or a complete load balance with