This is a note to let you know that I've just added the patch titled sched/uclamp: Make select_idle_capacity() use util_fits_cpu() to the 6.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: sched-uclamp-make-select_idle_capacity-use-util_fits.patch and it can be found in the queue-6.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit dcc34320f58af8c952af3ed21925ef1e62d8ab45 Author: Qais Yousef <qais.yousef@xxxxxxx> Date: Thu Aug 4 15:36:04 2022 +0100 sched/uclamp: Make select_idle_capacity() use util_fits_cpu() [ Upstream commit b759caa1d9f667b94727b2ad12589cbc4ce13a82 ] 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@xxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220804143609.515789-5-qais.yousef@xxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index abe0e6baaa2e..892ea83864a7 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6603,21 +6603,23 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, bool 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_rq_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) {