From 13fa3326efb257f0fa6aaf17ef509de79e47e301 Mon Sep 17 00:00:00 2001 From: Keisuke Nishimura Date: Wed, 10 Jan 2024 14:17:07 +0100 Subject: [PATCH] sched/fair: Take the scheduling domain into account in select_idle_core() [ Upstream commit 23d04d8c6b8ec339057264659b7834027f3e6a63 ] When picking a CPU on task wakeup, select_idle_core() has to take into account the scheduling domain where the function looks for the CPU. This is because the "isolcpus" kernel command line option can remove CPUs from the domain to isolate them from other SMT siblings. This change replaces the set of CPUs allowed to run the task from p->cpus_ptr by the intersection of p->cpus_ptr and sched_domain_span(sd) which is stored in the 'cpus' argument provided by select_idle_cpu(). Fixes: 9fe1f127b913 ("sched/fair: Merge select_idle_core/cpu()") Signed-off-by: Keisuke Nishimura Signed-off-by: Julia Lawall Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20240110131707.437301-2-keisuke.nishimura@inria.fr Signed-off-by: Sasha Levin --- kernel/sched/fair.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 1c4e54fffb8b..91c101ecfef9 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6656,7 +6656,7 @@ static int select_idle_core(struct task_struct *p, int core, struct cpumask *cpu if (!available_idle_cpu(cpu)) { idle = false; if (*idle_cpu == -1) { - if (sched_idle_cpu(cpu) && cpumask_test_cpu(cpu, p->cpus_ptr)) { + if (sched_idle_cpu(cpu) && cpumask_test_cpu(cpu, cpus)) { *idle_cpu = cpu; break; } @@ -6664,7 +6664,7 @@ static int select_idle_core(struct task_struct *p, int core, struct cpumask *cpu } break; } - if (*idle_cpu == -1 && cpumask_test_cpu(cpu, p->cpus_ptr)) + if (*idle_cpu == -1 && cpumask_test_cpu(cpu, cpus)) *idle_cpu = cpu; }