Right now, update_tasks_cpumask() is not supposed to be called with top cpuset. With cpuset partition that takes CPUs away from the top cpuset, we may want to consider adjusting the cpu_allows mask of the tasks in the top cpuset as well. However, we need more investigation to figure out a way to do that without breaking non-cgroup aware applications in the top cpuset. So move the top_cpuset check into update_tasks_cpumask() and add a comment about possible future work. Signed-off-by: Waiman Long <longman@xxxxxxxxxx> --- kernel/cgroup/cpuset.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 9390bfd9f1cd..d90f33b068a3 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -1128,6 +1128,14 @@ static void update_tasks_cpumask(struct cpuset *cs) struct css_task_iter it; struct task_struct *task; + /* + * TODO: With cpuset partition that takes CPUs away from the top + * cpuset, we may want to properly adjust the cpus_allowed mask of + * tasks in the top cpuset as well. + */ + if (cs == &top_cpuset) + return; + css_task_iter_start(&cs->css, 0, &it); while ((task = css_task_iter_next(&it))) set_cpus_allowed_ptr(task, cs->effective_cpus); @@ -2092,12 +2100,7 @@ static int update_prstate(struct cpuset *cs, int new_prs) update_flag(CS_CPU_EXCLUSIVE, cs, 0); } - /* - * Update cpumask of parent's tasks except when it is the top - * cpuset as some system daemons cannot be mapped to other CPUs. - */ - if (parent != &top_cpuset) - update_tasks_cpumask(parent); + update_tasks_cpumask(parent); if (parent->child_ecpus_count) update_sibling_cpumasks(parent, cs, &tmpmask); -- 2.27.0
