From bbe5ab8191a33572c11be8628c55b79246307125 Mon Sep 17 00:00:00 2001 From: Waiman Long Date: Tue, 31 Mar 2026 11:11:07 -0400 Subject: cgroup/cpuset: Simplify setsched decision check in task iteration loop of cpuset_can_attach() Centralize the check required to run security_task_setscheduler() in the task iteration loop of cpuset_can_attach() outside of the loop as it has no dependency on the characteristics of the tasks themselves. There is no functional change. Signed-off-by: Waiman Long Signed-off-by: Tejun Heo --- kernel/cgroup/cpuset.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index d21868455341..58c5b7b72cca 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -2988,7 +2988,7 @@ static int cpuset_can_attach(struct cgroup_taskset *tset) struct cgroup_subsys_state *css; struct cpuset *cs, *oldcs; struct task_struct *task; - bool cpus_updated, mems_updated; + bool setsched_check; int ret; /* used later by cpuset_attach() */ @@ -3003,20 +3003,21 @@ static int cpuset_can_attach(struct cgroup_taskset *tset) if (ret) goto out_unlock; - cpus_updated = !cpumask_equal(cs->effective_cpus, oldcs->effective_cpus); - mems_updated = !nodes_equal(cs->effective_mems, oldcs->effective_mems); + /* + * Skip rights over task setsched check in v2 when nothing changes, + * migration permission derives from hierarchy ownership in + * cgroup_procs_write_permission()). + */ + setsched_check = !cpuset_v2() || + !cpumask_equal(cs->effective_cpus, oldcs->effective_cpus) || + !nodes_equal(cs->effective_mems, oldcs->effective_mems); cgroup_taskset_for_each(task, css, tset) { ret = task_can_attach(task); if (ret) goto out_unlock; - /* - * Skip rights over task check in v2 when nothing changes, - * migration permission derives from hierarchy ownership in - * cgroup_procs_write_permission()). - */ - if (!cpuset_v2() || (cpus_updated || mems_updated)) { + if (setsched_check) { ret = security_task_setscheduler(task); if (ret) goto out_unlock; -- cgit v1.2.3