Merge branch 'sched/new-API-sched_setscheduler' of git://git.kernel.org/pub/scm/linux...

[pandora-kernel.git] / kernel / sched.c

diff --git a/kernel/sched.c b/kernel/sched.c
index c74b0d2..2317a21 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4995,16 +4995,8 @@ __setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio)
        set_load_weight(p);
 }
 
-/**
- * sched_setscheduler - change the scheduling policy and/or RT priority of a thread.
- * @p: the task in question.
- * @policy: new policy.
- * @param: structure containing the new RT priority.
- *
- * NOTE that the task may be already dead.
- */
-int sched_setscheduler(struct task_struct *p, int policy,
-                      struct sched_param *param)
+static int __sched_setscheduler(struct task_struct *p, int policy,
+                               struct sched_param *param, bool user)
 {
        int retval, oldprio, oldpolicy = -1, on_rq, running;
        unsigned long flags;
@@ -5036,7 +5028,7 @@ recheck:
        /*
         * Allow unprivileged RT tasks to decrease priority:
         */
-       if (!capable(CAP_SYS_NICE)) {
+       if (user && !capable(CAP_SYS_NICE)) {
                if (rt_policy(policy)) {
                        unsigned long rlim_rtprio;
 
@@ -5072,7 +5064,8 @@ recheck:
         * Do not allow realtime tasks into groups that have no runtime
         * assigned.
         */
-       if (rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0)
+       if (user
+           && rt_policy(policy) && task_group(p)->rt_bandwidth.rt_runtime == 0)
                return -EPERM;
 #endif
 
@@ -5121,8 +5114,39 @@ recheck:
 
        return 0;
 }
+
+/**
+ * sched_setscheduler - change the scheduling policy and/or RT priority of a thread.
+ * @p: the task in question.
+ * @policy: new policy.
+ * @param: structure containing the new RT priority.
+ *
+ * NOTE that the task may be already dead.
+ */
+int sched_setscheduler(struct task_struct *p, int policy,
+                      struct sched_param *param)
+{
+       return __sched_setscheduler(p, policy, param, true);
+}
 EXPORT_SYMBOL_GPL(sched_setscheduler);
 
+/**
+ * sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace.
+ * @p: the task in question.
+ * @policy: new policy.
+ * @param: structure containing the new RT priority.
+ *
+ * Just like sched_setscheduler, only don't bother checking if the
+ * current context has permission.  For example, this is needed in
+ * stop_machine(): we create temporary high priority worker threads,
+ * but our caller might not have that capability.
+ */
+int sched_setscheduler_nocheck(struct task_struct *p, int policy,
+                              struct sched_param *param)
+{
+       return __sched_setscheduler(p, policy, param, false);
+}
+
 static int
 do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param)
 {