From: Qais Yousef qais.yousef@arm.com
commit b759caa1d9f667b94727b2ad12589cbc4ce13a82 upstream.
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.
Fixes: b4c9c9f15649 ("sched/fair: Prefer prev cpu in asymmetric wakeup path") Signed-off-by: Qais Yousef qais.yousef@arm.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Link: https://lore.kernel.org/r/20220804143609.515789-5-qais.yousef@arm.com (cherry picked from commit b759caa1d9f667b94727b2ad12589cbc4ce13a82) Signed-off-by: Qais Yousef (Google) qyousef@layalina.io Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- kernel/sched/fair.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
--- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6394,21 +6394,23 @@ static int select_idle_cpu(struct task_s static int select_idle_capacity(struct task_struct *p, struct sched_domain *sd, int target) { - unsigned long task_util, best_cap = 0; + unsigned long task_util, util_min, util_max, best_cap = 0; int cpu, best_cpu = -1; struct cpumask *cpus;
cpus = this_cpu_cpumask_var_ptr(select_idle_mask); cpumask_and(cpus, sched_domain_span(sd), p->cpus_ptr);
- 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);
for_each_cpu_wrap(cpu, cpus, target) { unsigned long cpu_cap = capacity_of(cpu);
if (!available_idle_cpu(cpu) && !sched_idle_cpu(cpu)) continue; - if (fits_capacity(task_util, cpu_cap)) + if (util_fits_cpu(task_util, util_min, util_max, cpu)) return cpu;
if (cpu_cap > best_cap) {