various scheduler patches

Index: linux-2.6/kernel/sched_rt.c
===================================================================
@@ -837,6 +837,8 @@ static void prio_changed_rt(struct rq *r
 
 static void task_tick_rt(struct rq *rq, struct task_struct *p)
 {
+	update_curr_rt(rq);
+
 	/*
 	 * RR tasks need a special form of timeslice management.
 	 * FIFO tasks have no timeslices.

Index: linux-2.6/include/linux/init_task.h
===================================================================
@@ -133,9 +133,10 @@ extern struct group_info init_groups;
 	.nr_cpus_allowed = NR_CPUS,					\
 	.mm		= NULL,						\
 	.active_mm	= &init_mm,					\
-	.run_list	= LIST_HEAD_INIT(tsk.run_list),			\
+	.rt		= {						\
+		.run_list	= LIST_HEAD_INIT(tsk.rt.run_list),	\
+		.time_slice	= HZ, },				\
 	.ioprio		= 0,						\
-	.time_slice	= HZ,						\
 	.tasks		= LIST_HEAD_INIT(tsk.tasks),			\
 	.ptrace_children= LIST_HEAD_INIT(tsk.ptrace_children),		\
 	.ptrace_list	= LIST_HEAD_INIT(tsk.ptrace_list),		\

Index: linux-2.6/include/linux/sched.h
===================================================================
@@ -934,6 +934,11 @@ struct sched_entity {
 #endif
 };
 
+struct sched_rt_entity {
+	struct list_head run_list;
+	unsigned int time_slice;
+};
+
 struct task_struct {
 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
 	void *stack;

@@ -950,9 +955,9 @@ struct task_struct {
 #endif
 
 	int prio, static_prio, normal_prio;
-	struct list_head run_list;
 	const struct sched_class *sched_class;
 	struct sched_entity se;
+	struct sched_rt_entity rt;
 
 #ifdef CONFIG_PREEMPT_NOTIFIERS
 	/* list of struct preempt_notifier: */

@@ -977,7 +982,6 @@ struct task_struct {
 	unsigned int policy;
 	cpumask_t cpus_allowed;
 	int nr_cpus_allowed;
-	unsigned int time_slice;
 
 #ifdef CONFIG_PREEMPT_RCU
 	int rcu_read_lock_nesting;

Index: linux-2.6/kernel/sched_rt.c
===================================================================
@@ -111,7 +111,7 @@ static void enqueue_task_rt(struct rq *r
 {
 	struct rt_prio_array *array = &rq->rt.active;
 
-	list_add_tail(&p->run_list, array->queue + p->prio);
+	list_add_tail(&p->rt.run_list, array->queue + p->prio);
 	__set_bit(p->prio, array->bitmap);
 	inc_cpu_load(rq, p->se.load.weight);
 

@@ -127,7 +127,7 @@ static void dequeue_task_rt(struct rq *r
 
 	update_curr_rt(rq);
 
-	list_del(&p->run_list);
+	list_del(&p->rt.run_list);
 	if (list_empty(array->queue + p->prio))
 		__clear_bit(p->prio, array->bitmap);
 	dec_cpu_load(rq, p->se.load.weight);

@@ -143,7 +143,7 @@ static void requeue_task_rt(struct rq *r
 {
 	struct rt_prio_array *array = &rq->rt.active;
 
-	list_move_tail(&p->run_list, array->queue + p->prio);
+	list_move_tail(&p->rt.run_list, array->queue + p->prio);
 }
 
 static void

@@ -212,7 +212,7 @@ static struct task_struct *pick_next_tas
 		return NULL;
 
 	queue = array->queue + idx;
-	next = list_entry(queue->next, struct task_struct, run_list);
+	next = list_entry(queue->next, struct task_struct, rt.run_list);
 
 	next->se.exec_start = rq->clock;
 

@@ -261,14 +261,14 @@ static struct task_struct *pick_next_hig
 	queue = array->queue + idx;
 	BUG_ON(list_empty(queue));
 
-	next = list_entry(queue->next, struct task_struct, run_list);
+	next = list_entry(queue->next, struct task_struct, rt.run_list);
 	if (unlikely(pick_rt_task(rq, next, cpu)))
 		goto out;
 
 	if (queue->next->next != queue) {
 		/* same prio task */
 		next = list_entry(queue->next->next, struct task_struct,
-				  run_list);
+				  rt.run_list);
 		if (pick_rt_task(rq, next, cpu))
 			goto out;
 	}

@@ -282,7 +282,7 @@ static struct task_struct *pick_next_hig
 	queue = array->queue + idx;
 	BUG_ON(list_empty(queue));
 
-	list_for_each_entry(next, queue, run_list) {
+	list_for_each_entry(next, queue, rt.run_list) {
 		if (pick_rt_task(rq, next, cpu))
 			goto out;
 	}

@@ -846,16 +846,16 @@ static void task_tick_rt(struct rq *rq, 
 	if (p->policy != SCHED_RR)
 		return;
 
-	if (--p->time_slice)
+	if (--p->rt.time_slice)
 		return;
 
-	p->time_slice = DEF_TIMESLICE;
+	p->rt.time_slice = DEF_TIMESLICE;
 
 	/*
 	 * Requeue to the end of queue if we are not the only element
 	 * on the queue:
 	 */
-	if (p->run_list.prev != p->run_list.next) {
+	if (p->rt.run_list.prev != p->rt.run_list.next) {
 		requeue_task_rt(rq, p);
 		set_tsk_need_resched(p);
 	}

Index: linux-2.6/mm/oom_kill.c
===================================================================
@@ -286,7 +286,7 @@ static void __oom_kill_task(struct task_
 	 * all the memory it needs. That way it should be able to
 	 * exit() and clear out its resources quickly...
 	 */
-	p->time_slice = HZ;
+	p->rt.time_slice = HZ;
 	set_tsk_thread_flag(p, TIF_MEMDIE);
 
 	force_sig(SIGKILL, p);

Index: linux-2.6/kernel/sched.c
===================================================================
@@ -1685,7 +1685,7 @@ static void __sched_fork(struct task_str
 	p->se.wait_max			= 0;
 #endif
 
-	INIT_LIST_HEAD(&p->run_list);
+	INIT_LIST_HEAD(&p->rt.run_list);
 	p->se.on_rq = 0;
 
 #ifdef CONFIG_PREEMPT_NOTIFIERS

Index: linux-2.6/include/asm-generic/resource.h
===================================================================
@@ -44,8 +44,8 @@
 #define RLIMIT_NICE		13	/* max nice prio allowed to raise to
 					   0-39 for nice level 19 .. -20 */
 #define RLIMIT_RTPRIO		14	/* maximum realtime priority */
-
-#define RLIM_NLIMITS		15
+#define RLIMIT_RTTIME		15	/* timeout for RT tasks in us */
+#define RLIM_NLIMITS		16
 
 /*
  * SuS says limits have to be unsigned.

@@ -86,6 +86,7 @@
 	[RLIMIT_MSGQUEUE]	= {   MQ_BYTES_MAX,   MQ_BYTES_MAX },	\
 	[RLIMIT_NICE]		= { 0, 0 },				\
 	[RLIMIT_RTPRIO]		= { 0, 0 },				\
+	[RLIMIT_RTTIME]		= {  RLIM_INFINITY,  RLIM_INFINITY },	\
 }
 
 #endif	/* __KERNEL__ */

Index: linux-2.6/kernel/sched_rt.c
===================================================================
@@ -116,6 +116,9 @@ static void enqueue_task_rt(struct rq *r
 	inc_cpu_load(rq, p->se.load.weight);
 
 	inc_rt_tasks(p, rq);
+
+	if (wakeup)
+		p->rt.timeout = 0;
 }
 
 /*

@@ -834,11 +837,38 @@ static void prio_changed_rt(struct rq *r
 	}
 }
 
+static void watchdog(struct rq *rq, struct task_struct *p)
+{
+	unsigned long soft, hard;
+
+	if (!p->signal)
+		return;
+
+	soft = p->signal->rlim[RLIMIT_RTTIME].rlim_cur;
+	hard = p->signal->rlim[RLIMIT_RTTIME].rlim_max;
+
+	if (soft != RLIM_INFINITY) {
+		unsigned long next;
+
+		p->rt.timeout++;
+		next = DIV_ROUND_UP(min(soft, hard), USEC_PER_SEC/HZ);
+		if (next > p->rt.timeout) {
+			u64 next_time = p->se.sum_exec_runtime;
+
+			next_time += next * (NSEC_PER_SEC/HZ);
+			if (p->it_sched_expires > next_time)
+				p->it_sched_expires = next_time;
+		} else
+			p->it_sched_expires = p->se.sum_exec_runtime;
+	}
+}
 
 static void task_tick_rt(struct rq *rq, struct task_struct *p)
 {
 	update_curr_rt(rq);
 
+	watchdog(rq, p);
+
 	/*
 	 * RR tasks need a special form of timeslice management.
 	 * FIFO tasks have no timeslices.

Index: linux-2.6/include/linux/sched.h
===================================================================
@@ -937,6 +937,7 @@ struct sched_entity {
 struct sched_rt_entity {
 	struct list_head run_list;
 	unsigned int time_slice;
+	unsigned long timeout;
 };
 
 struct task_struct {

Index: linux-2.6/kernel/posix-cpu-timers.c
===================================================================
@@ -967,6 +967,7 @@ static void check_thread_timers(struct t
 {
 	int maxfire;
 	struct list_head *timers = tsk->cpu_timers;
+	struct signal_struct *const sig = tsk->signal;
 
 	maxfire = 20;
 	tsk->it_prof_expires = cputime_zero;

@@ -1011,6 +1012,33 @@ static void check_thread_timers(struct t
 		t->firing = 1;
 		list_move_tail(&t->entry, firing);
 	}
+
+	/*
+	 * Check for the special case thread timers.
+	 */
+	if (sig->rlim[RLIMIT_RTTIME].rlim_cur != RLIM_INFINITY) {
+		unsigned long hard = sig->rlim[RLIMIT_RTTIME].rlim_max;
+		unsigned long *soft = &sig->rlim[RLIMIT_RTTIME].rlim_cur;
+
+		if (tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) {
+			/*
+			 * At the hard limit, we just die.
+			 * No need to calculate anything else now.
+			 */
+			__group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk);
+			return;
+		}
+		if (tsk->rt.timeout > DIV_ROUND_UP(*soft, USEC_PER_SEC/HZ)) {
+			/*
+			 * At the soft limit, send a SIGXCPU every second.
+			 */
+			if (sig->rlim[RLIMIT_RTTIME].rlim_cur
+			    < sig->rlim[RLIMIT_RTTIME].rlim_max)
+				sig->rlim[RLIMIT_RTTIME].rlim_cur += USEC_PER_SEC;
+
+			__group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk);
+		}
+	}
 }
 
 /*