Commit 08d473dd authored by Peter Zijlstra's avatar Peter Zijlstra
Browse files

sched/fair: Small cleanup to update_newidle_cost() 



Simplify code by adding a few variables.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarDietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: default avatarDietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: default avatarChris Mason <clm@meta.com>
Link: https://patch.msgid.link/20251107161739.655208666@infradead.org
parent e78e70db

kernel/sched/fair.c

+7 −4
Original line number Diff line number Diff line
@@ -12226,22 +12226,25 @@ void update_max_interval(void) 


static inline bool update_newidle_cost(struct sched_domain *sd, u64 cost)

{

	unsigned long next_decay = sd->last_decay_max_lb_cost + HZ;

	unsigned long now = jiffies;



	if (cost > sd->max_newidle_lb_cost) {

		/*

		 * Track max cost of a domain to make sure to not delay the

		 * next wakeup on the CPU.

		 */

		sd->max_newidle_lb_cost = cost;

		sd->last_decay_max_lb_cost = jiffies;

	} else if (time_after(jiffies, sd->last_decay_max_lb_cost + HZ)) {

		sd->last_decay_max_lb_cost = now;



	} else if (time_after(now, next_decay)) {

		/*

		 * Decay the newidle max times by ~1% per second to ensure that

		 * it is not outdated and the current max cost is actually

		 * shorter.

		 */

		sd->max_newidle_lb_cost = (sd->max_newidle_lb_cost * 253) / 256;

		sd->last_decay_max_lb_cost = jiffies;



		sd->last_decay_max_lb_cost = now;

		return true;

	}