From 4f05b98d54b140ed3c5851d5d5156e9918c6305d Mon Sep 17 00:00:00 2001 From: Michal Schmidt Date: Fri, 25 Jan 2008 21:08:33 +0100 Subject: sched: fix, always create kernel threads with normal priority Ensure that the kernel threads are created with the usual nice level and affinity even if kthreadd's properties were changed from the default by root. Signed-off-by: Michal Schmidt Signed-off-by: Ingo Molnar --- kernel/kthread.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/kernel/kthread.c b/kernel/kthread.c index dcfe724..0ac8878 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -15,6 +15,8 @@ #include #include +#define KTHREAD_NICE_LEVEL (-5) + static DEFINE_SPINLOCK(kthread_create_lock); static LIST_HEAD(kthread_create_list); struct task_struct *kthreadd_task; @@ -94,10 +96,18 @@ static void create_kthread(struct kthread_create_info *create) if (pid < 0) { create->result = ERR_PTR(pid); } else { + struct sched_param param = { .sched_priority = 0 }; wait_for_completion(&create->started); read_lock(&tasklist_lock); create->result = find_task_by_pid(pid); read_unlock(&tasklist_lock); + /* + * root may have changed our (kthreadd's) priority or CPU mask. + * The kernel thread should not inherit these properties. + */ + sched_setscheduler(create->result, SCHED_NORMAL, ¶m); + set_user_nice(create->result, KTHREAD_NICE_LEVEL); + set_cpus_allowed(create->result, CPU_MASK_ALL); } complete(&create->done); } @@ -221,7 +231,7 @@ int kthreadd(void *unused) /* Setup a clean context for our children to inherit. */ set_task_comm(tsk, "kthreadd"); ignore_signals(tsk); - set_user_nice(tsk, -5); + set_user_nice(tsk, KTHREAD_NICE_LEVEL); set_cpus_allowed(tsk, CPU_MASK_ALL); current->flags |= PF_NOFREEZE; -- cgit v1.1