Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 3277c4c3 authored by Pavankumar Kondeti's avatar Pavankumar Kondeti
Browse files

sched/fair: Add support for need_idle task placement 



Any task with PF_WAKE_UP_IDLE flag set or any task woken up
by another task with PF_WAKE_UP_IDLE flag set is placed on
an idle CPU. This only affects CPU selection with in a
selected cluster. If all the CPUs are active in the selected
cluster, the task is placed on the least loaded CPU.

Change-Id: Icf663abb60447508e9934ba92b19ffbfbbb6d3f5
Signed-off-by: default avatarPavankumar Kondeti <pkondeti@codeaurora.org>
parent 968a4abf

kernel/sched/fair.c

+21 −1
Original line number Diff line number Diff line
@@ -6967,6 +6967,7 @@ static inline bool task_fits_max(struct task_struct *p, int cpu) 
struct find_best_target_env {

	struct cpumask *rtg_target;

	bool placement_boost;

	bool need_idle;

};



static inline bool skip_sg(struct task_struct *p, struct sched_group *sg,
@@ -7261,6 +7262,13 @@ static inline int find_best_target(struct task_struct *p, int *backup_cpu, 


	} while (sg = sg->next, sg != sd->groups);



	if (fbt_env->need_idle) {

		if (best_idle_cpu != -1) {

			target_cpu = best_idle_cpu;

			best_idle_cpu = -1;

		}

	}



	/*

	 * For non latency sensitive tasks, cases B and C in the previous loop,

	 * we pick the best IDLE CPU only if we was not able to find a target
@@ -7461,6 +7469,12 @@ static inline struct energy_env *get_eenv(struct task_struct *p, int prev_cpu) 
	return eenv;

}



static inline int wake_to_idle(struct task_struct *p)

{

	return (current->flags & PF_WAKE_UP_IDLE) ||

		 (p->flags & PF_WAKE_UP_IDLE);

}



static inline struct cpumask *find_rtg_target(struct task_struct *p)

{

	struct related_thread_group *grp;
@@ -7498,6 +7512,10 @@ static int find_energy_efficient_cpu(struct sched_domain *sd, 
	struct energy_env *eenv;

	struct cpumask *rtg_target = find_rtg_target(p);

	struct find_best_target_env fbt_env;

	bool need_idle = wake_to_idle(p);



	if (need_idle)

		sync = 0;



	if (sysctl_sched_sync_hint_enable && sync &&

				bias_to_waker_cpu(p, cpu, rtg_target)) {
@@ -7553,6 +7571,7 @@ static int find_energy_efficient_cpu(struct sched_domain *sd, 


		fbt_env.rtg_target = rtg_target;

		fbt_env.placement_boost = task_placement_boost_enabled(p);

		fbt_env.need_idle = need_idle;



		/* Find a cpu with sufficient capacity */

		eenv->cpu[EAS_CPU_NXT].cpu_id = find_best_target(p,
@@ -7577,7 +7596,8 @@ static int find_energy_efficient_cpu(struct sched_domain *sd, 
		return energy_cpu;

	}



	if (use_fbt && (rtg_target != NULL || fbt_env.placement_boost))

	if (use_fbt && (rtg_target != NULL || fbt_env.placement_boost ||

			fbt_env.need_idle))

		return eenv->cpu[EAS_CPU_NXT].cpu_id;



	/* find most energy-efficient CPU */