Commit a2e7f03e authored by Qais Yousef's avatar Qais Yousef Committed by Peter Zijlstra
Browse files

sched/uclamp: Make asym_fits_capacity() use util_fits_cpu() 



Use the new util_fits_cpu() to ensure migration margin and capacity
pressure are taken into account correctly when uclamp is being used
otherwise we will fail to consider CPUs as fitting in scenarios where
they should.

s/asym_fits_capacity/asym_fits_cpu/ to better reflect what it does now.

Fixes: b4c9c9f1 ("sched/fair: Prefer prev cpu in asymmetric wakeup path")
Signed-off-by: default avatarQais Yousef <qais.yousef@arm.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220804143609.515789-6-qais.yousef@arm.com
parent b759caa1

kernel/sched/fair.c

+13 −8
Original line number Diff line number Diff line
@@ -6807,10 +6807,13 @@ select_idle_capacity(struct task_struct *p, struct sched_domain *sd, int target) 
	return best_cpu;

}



static inline bool asym_fits_capacity(unsigned long task_util, int cpu)

static inline bool asym_fits_cpu(unsigned long util,

				 unsigned long util_min,

				 unsigned long util_max,

				 int cpu)

{

	if (sched_asym_cpucap_active())

		return fits_capacity(task_util, capacity_of(cpu));

		return util_fits_cpu(util, util_min, util_max, cpu);



	return true;

}
@@ -6822,7 +6825,7 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) 
{

	bool has_idle_core = false;

	struct sched_domain *sd;

	unsigned long task_util;

	unsigned long task_util, util_min, util_max;

	int i, recent_used_cpu;



	/*
@@ -6831,7 +6834,9 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) 
	 */

	if (sched_asym_cpucap_active()) {

		sync_entity_load_avg(&p->se);

		task_util = uclamp_task_util(p);

		task_util = task_util_est(p);

		util_min = uclamp_eff_value(p, UCLAMP_MIN);

		util_max = uclamp_eff_value(p, UCLAMP_MAX);

	}



	/*
@@ -6840,7 +6845,7 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) 
	lockdep_assert_irqs_disabled();



	if ((available_idle_cpu(target) || sched_idle_cpu(target)) &&

	    asym_fits_capacity(task_util, target))

	    asym_fits_cpu(task_util, util_min, util_max, target))

		return target;



	/*
@@ -6848,7 +6853,7 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) 
	 */

	if (prev != target && cpus_share_cache(prev, target) &&

	    (available_idle_cpu(prev) || sched_idle_cpu(prev)) &&

	    asym_fits_capacity(task_util, prev))

	    asym_fits_cpu(task_util, util_min, util_max, prev))

		return prev;



	/*
@@ -6863,7 +6868,7 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) 
	    in_task() &&

	    prev == smp_processor_id() &&

	    this_rq()->nr_running <= 1 &&

	    asym_fits_capacity(task_util, prev)) {

	    asym_fits_cpu(task_util, util_min, util_max, prev)) {

		return prev;

	}
@@ -6875,7 +6880,7 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) 
	    cpus_share_cache(recent_used_cpu, target) &&

	    (available_idle_cpu(recent_used_cpu) || sched_idle_cpu(recent_used_cpu)) &&

	    cpumask_test_cpu(p->recent_used_cpu, p->cpus_ptr) &&

	    asym_fits_capacity(task_util, recent_used_cpu)) {

	    asym_fits_cpu(task_util, util_min, util_max, recent_used_cpu)) {

		return recent_used_cpu;

	}