sched/deadline: Add SCHED_DEADLINE structures & implementation

[deliverable/linux.git] / include / linux / sched.h

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 86025b6c6387edf30fcfa413762b9bdb7180b0c4..6c196794fc12ae64b1ddb82aa8b2f3d626828adf 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -97,6 +97,10 @@ struct sched_param {
  * Given this task model, there are a multiplicity of scheduling algorithms
  * and policies, that can be used to ensure all the tasks will make their
  * timing constraints.
+ *
+ * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
+ * only user of this new interface. More information about the algorithm
+ * available in the scheduling class file or in Documentation/.
  */
 struct sched_attr {
        u32 size;
@@ -1088,6 +1092,45 @@ struct sched_rt_entity {
 #endif
 };
 
+struct sched_dl_entity {
+       struct rb_node  rb_node;
+
+       /*
+        * Original scheduling parameters. Copied here from sched_attr
+        * during sched_setscheduler2(), they will remain the same until
+        * the next sched_setscheduler2().
+        */
+       u64 dl_runtime;         /* maximum runtime for each instance    */
+       u64 dl_deadline;        /* relative deadline of each instance   */
+
+       /*
+        * Actual scheduling parameters. Initialized with the values above,
+        * they are continously updated during task execution. Note that
+        * the remaining runtime could be < 0 in case we are in overrun.
+        */
+       s64 runtime;            /* remaining runtime for this instance  */
+       u64 deadline;           /* absolute deadline for this instance  */
+       unsigned int flags;     /* specifying the scheduler behaviour   */
+
+       /*
+        * Some bool flags:
+        *
+        * @dl_throttled tells if we exhausted the runtime. If so, the
+        * task has to wait for a replenishment to be performed at the
+        * next firing of dl_timer.
+        *
+        * @dl_new tells if a new instance arrived. If so we must
+        * start executing it with full runtime and reset its absolute
+        * deadline;
+        */
+       int dl_throttled, dl_new;
+
+       /*
+        * Bandwidth enforcement timer. Each -deadline task has its
+        * own bandwidth to be enforced, thus we need one timer per task.
+        */
+       struct hrtimer dl_timer;
+};
 
 struct rcu_node;
 
@@ -1124,6 +1167,7 @@ struct task_struct {
 #ifdef CONFIG_CGROUP_SCHED
        struct task_group *sched_task_group;
 #endif
+       struct sched_dl_entity dl;
 
 #ifdef CONFIG_PREEMPT_NOTIFIERS
        /* list of struct preempt_notifier: */
@@ -2099,7 +2143,7 @@ extern void wake_up_new_task(struct task_struct *tsk);
 #else
  static inline void kick_process(struct task_struct *tsk) { }
 #endif
-extern void sched_fork(unsigned long clone_flags, struct task_struct *p);
+extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
 extern void sched_dead(struct task_struct *p);
 
 extern void proc_caches_init(void);