1 files changed, 27 insertions, 9 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index dcd553cc4ee8..52b98675acb2 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4422,7 +4422,7 @@ int task_nice(const struct task_struct *p)
 {
         return TASK_NICE(p);
 }
-EXPORT_SYMBOL_GPL(task_nice);
+EXPORT_SYMBOL(task_nice);
 
 /**
  * idle_cpu - is a given cpu idle currently?
@@ -5100,7 +5100,7 @@ long sys_sched_rr_get_interval(pid_t pid, struct timespec __user *interval)
         time_slice = 0;
         if (p->policy == SCHED_RR) {
                 time_slice = DEF_TIMESLICE;
-        } else {
+        } else if (p->policy != SCHED_FIFO) {
                 struct sched_entity *se = &p->se;
                 unsigned long flags;
                 struct rq *rq;
@@ -7625,6 +7625,11 @@ void sched_move_task(struct task_struct *tsk)
 
         set_task_rq(tsk, task_cpu(tsk));
 
+#ifdef CONFIG_FAIR_GROUP_SCHED
+        if (tsk->sched_class->moved_group)
+                tsk->sched_class->moved_group(tsk);
+#endif
+
         if (on_rq) {
                 if (unlikely(running))
                         tsk->sched_class->set_curr_task(rq);
@@ -7721,9 +7726,7 @@ static unsigned long to_ratio(u64 period, u64 runtime)
         if (runtime == RUNTIME_INF)
                 return 1ULL << 16;
 
-        runtime *= (1ULL << 16);
-        div64_64(runtime, period);
-        return runtime;
+        return div64_64(runtime << 16, period);
 }
 
 static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
@@ -7747,25 +7750,40 @@ static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
         return total + to_ratio(period, runtime) < global_ratio;
 }
 
+/* Must be called with tasklist_lock held */
+static inline int tg_has_rt_tasks(struct task_group *tg)
+{
+        struct task_struct *g, *p;
+        do_each_thread(g, p) {
+                if (rt_task(p) && rt_rq_of_se(&p->rt)->tg == tg)
+                        return 1;
+        } while_each_thread(g, p);
+        return 0;
+}
+
 int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us)
 {
         u64 rt_runtime, rt_period;
         int err = 0;
 
-        rt_period = sysctl_sched_rt_period * NSEC_PER_USEC;
+        rt_period = (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
         rt_runtime = (u64)rt_runtime_us * NSEC_PER_USEC;
         if (rt_runtime_us == -1)
-                rt_runtime = rt_period;
+                rt_runtime = RUNTIME_INF;
 
         mutex_lock(&rt_constraints_mutex);
+        read_lock(&tasklist_lock);
+        if (rt_runtime_us == 0 && tg_has_rt_tasks(tg)) {
+                err = -EBUSY;
+                goto unlock;
+        }
         if (!__rt_schedulable(tg, rt_period, rt_runtime)) {
                 err = -EINVAL;
                 goto unlock;
         }
-        if (rt_runtime_us == -1)
-                rt_runtime = RUNTIME_INF;
         tg->rt_runtime = rt_runtime;
  unlock:
+        read_unlock(&tasklist_lock);
         mutex_unlock(&rt_constraints_mutex);
 
         return err;