*/
unsigned long nr_running;
#ifdef CONFIG_SMP
+ unsigned long prio_bias;
unsigned long cpu_load[3];
#endif
unsigned long long nr_switches;
return prio;
}
+#ifdef CONFIG_SMP
+static inline void inc_prio_bias(runqueue_t *rq, int prio)
+{
+ rq->prio_bias += MAX_PRIO - prio;
+}
+
+static inline void dec_prio_bias(runqueue_t *rq, int prio)
+{
+ rq->prio_bias -= MAX_PRIO - prio;
+}
+
+static inline void inc_nr_running(task_t *p, runqueue_t *rq)
+{
+ rq->nr_running++;
+ if (rt_task(p)) {
+ if (p != rq->migration_thread)
+ /*
+ * The migration thread does the actual balancing. Do
+ * not bias by its priority as the ultra high priority
+ * will skew balancing adversely.
+ */
+ inc_prio_bias(rq, p->prio);
+ } else
+ inc_prio_bias(rq, p->static_prio);
+}
+
+static inline void dec_nr_running(task_t *p, runqueue_t *rq)
+{
+ rq->nr_running--;
+ if (rt_task(p)) {
+ if (p != rq->migration_thread)
+ dec_prio_bias(rq, p->prio);
+ } else
+ dec_prio_bias(rq, p->static_prio);
+}
+#else
+static inline void inc_prio_bias(runqueue_t *rq, int prio)
+{
+}
+
+static inline void dec_prio_bias(runqueue_t *rq, int prio)
+{
+}
+
+static inline void inc_nr_running(task_t *p, runqueue_t *rq)
+{
+ rq->nr_running++;
+}
+
+static inline void dec_nr_running(task_t *p, runqueue_t *rq)
+{
+ rq->nr_running--;
+}
+#endif
+
/*
* __activate_task - move a task to the runqueue.
*/
static inline void __activate_task(task_t *p, runqueue_t *rq)
{
enqueue_task(p, rq->active);
- rq->nr_running++;
+ inc_nr_running(p, rq);
}
/*
static inline void __activate_idle_task(task_t *p, runqueue_t *rq)
{
enqueue_task_head(p, rq->active);
- rq->nr_running++;
+ inc_nr_running(p, rq);
}
static int recalc_task_prio(task_t *p, unsigned long long now)
}
#endif
- p->prio = recalc_task_prio(p, now);
+ if (!rt_task(p))
+ p->prio = recalc_task_prio(p, now);
/*
* This checks to make sure it's not an uninterruptible task
*/
static void deactivate_task(struct task_struct *p, runqueue_t *rq)
{
- rq->nr_running--;
+ dec_nr_running(p, rq);
dequeue_task(p, p->array);
p->array = NULL;
}
#ifdef CONFIG_SMP
static void resched_task(task_t *p)
{
- int need_resched, nrpolling;
+ int cpu;
assert_spin_locked(&task_rq(p)->lock);
- /* minimise the chance of sending an interrupt to poll_idle() */
- nrpolling = test_tsk_thread_flag(p,TIF_POLLING_NRFLAG);
- need_resched = test_and_set_tsk_thread_flag(p,TIF_NEED_RESCHED);
- nrpolling |= test_tsk_thread_flag(p,TIF_POLLING_NRFLAG);
+ if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED)))
+ return;
+
+ set_tsk_thread_flag(p, TIF_NEED_RESCHED);
+
+ cpu = task_cpu(p);
+ if (cpu == smp_processor_id())
+ return;
- if (!need_resched && !nrpolling && (task_cpu(p) != smp_processor_id()))
- smp_send_reschedule(task_cpu(p));
+ /* NEED_RESCHED must be visible before we test POLLING_NRFLAG */
+ smp_mb();
+ if (!test_tsk_thread_flag(p, TIF_POLLING_NRFLAG))
+ smp_send_reschedule(cpu);
}
#else
static inline void resched_task(task_t *p)
{
+ assert_spin_locked(&task_rq(p)->lock);
set_tsk_need_resched(p);
}
#endif
* We want to under-estimate the load of migration sources, to
* balance conservatively.
*/
-static inline unsigned long source_load(int cpu, int type)
+static inline unsigned long __source_load(int cpu, int type, enum idle_type idle)
{
runqueue_t *rq = cpu_rq(cpu);
- unsigned long load_now = rq->nr_running * SCHED_LOAD_SCALE;
+ unsigned long running = rq->nr_running;
+ unsigned long source_load, cpu_load = rq->cpu_load[type-1],
+ load_now = running * SCHED_LOAD_SCALE;
+
if (type == 0)
- return load_now;
+ source_load = load_now;
+ else
+ source_load = min(cpu_load, load_now);
+
+ if (running > 1 || (idle == NOT_IDLE && running))
+ /*
+ * If we are busy rebalancing the load is biased by
+ * priority to create 'nice' support across cpus. When
+ * idle rebalancing we should only bias the source_load if
+ * there is more than one task running on that queue to
+ * prevent idle rebalance from trying to pull tasks from a
+ * queue with only one running task.
+ */
+ source_load = source_load * rq->prio_bias / running;
+
+ return source_load;
+}
- return min(rq->cpu_load[type-1], load_now);
+static inline unsigned long source_load(int cpu, int type)
+{
+ return __source_load(cpu, type, NOT_IDLE);
}
/*
* Return a high guess at the load of a migration-target cpu
*/
-static inline unsigned long target_load(int cpu, int type)
+static inline unsigned long __target_load(int cpu, int type, enum idle_type idle)
{
runqueue_t *rq = cpu_rq(cpu);
- unsigned long load_now = rq->nr_running * SCHED_LOAD_SCALE;
+ unsigned long running = rq->nr_running;
+ unsigned long target_load, cpu_load = rq->cpu_load[type-1],
+ load_now = running * SCHED_LOAD_SCALE;
+
if (type == 0)
- return load_now;
+ target_load = load_now;
+ else
+ target_load = max(cpu_load, load_now);
+
+ if (running > 1 || (idle == NOT_IDLE && running))
+ target_load = target_load * rq->prio_bias / running;
+
+ return target_load;
+}
- return max(rq->cpu_load[type-1], load_now);
+static inline unsigned long target_load(int cpu, int type)
+{
+ return __target_load(cpu, type, NOT_IDLE);
}
/*
list_add_tail(&p->run_list, ¤t->run_list);
p->array = current->array;
p->array->nr_active++;
- rq->nr_running++;
+ inc_nr_running(p, rq);
}
set_need_resched();
} else
* the sleep_avg of the parent as well.
*/
rq = task_rq_lock(p->parent, &flags);
- if (p->first_time_slice) {
+ if (p->first_time_slice && task_cpu(p) == task_cpu(p->parent)) {
p->parent->time_slice += p->time_slice;
if (unlikely(p->parent->time_slice > task_timeslice(p)))
p->parent->time_slice = task_timeslice(p);
runqueue_t *this_rq, prio_array_t *this_array, int this_cpu)
{
dequeue_task(p, src_array);
- src_rq->nr_running--;
+ dec_nr_running(p, src_rq);
set_task_cpu(p, this_cpu);
- this_rq->nr_running++;
+ inc_nr_running(p, this_rq);
enqueue_task(p, this_array);
p->timestamp = (p->timestamp - src_rq->timestamp_last_tick)
+ this_rq->timestamp_last_tick;
/* Bias balancing toward cpus of our domain */
if (local_group)
- load = target_load(i, load_idx);
+ load = __target_load(i, load_idx, idle);
else
- load = source_load(i, load_idx);
+ load = __source_load(i, load_idx, idle);
avg_load += load;
}
/*
* find_busiest_queue - find the busiest runqueue among the cpus in group.
*/
-static runqueue_t *find_busiest_queue(struct sched_group *group)
+static runqueue_t *find_busiest_queue(struct sched_group *group,
+ enum idle_type idle)
{
unsigned long load, max_load = 0;
runqueue_t *busiest = NULL;
int i;
for_each_cpu_mask(i, group->cpumask) {
- load = source_load(i, 0);
+ load = __source_load(i, 0, idle);
if (load > max_load) {
max_load = load;
goto out_balanced;
}
- busiest = find_busiest_queue(group);
+ busiest = find_busiest_queue(group, idle);
if (!busiest) {
schedstat_inc(sd, lb_nobusyq[idle]);
goto out_balanced;
goto out_balanced;
}
- busiest = find_busiest_queue(group);
+ busiest = find_busiest_queue(group, NEWLY_IDLE);
if (!busiest) {
schedstat_inc(sd, lb_nobusyq[NEWLY_IDLE]);
goto out_balanced;
cpustat->idle = cputime64_add(cpustat->idle, tmp);
/* Account for system time used */
acct_update_integrals(p);
- /* Update rss highwater mark */
- update_mem_hiwater(p);
}
/*
goto out_unlock;
}
array = p->array;
- if (array)
+ if (array) {
dequeue_task(p, array);
+ dec_prio_bias(rq, p->static_prio);
+ }
old_prio = p->prio;
new_prio = NICE_TO_PRIO(nice);
if (array) {
enqueue_task(p, array);
+ inc_prio_bias(rq, p->static_prio);
/*
* If the task increased its priority or is running and
* lowered its priority, then reschedule its CPU:
return cpu_curr(cpu) == cpu_rq(cpu)->idle;
}
-EXPORT_SYMBOL_GPL(idle_cpu);
-
/**
* idle_task - return the idle task for a given cpu.
* @cpu: the processor in question.
#ifndef CONFIG_SMP
cpumask_t cpu_online_map = CPU_MASK_ALL;
-EXPORT_SYMBOL_GPL(cpu_online_map);
cpumask_t cpu_possible_map = CPU_MASK_ALL;
#endif
#ifdef CONFIG_HOTPLUG_CPU
case CPU_UP_CANCELED:
/* Unbind it from offline cpu so it can run. Fall thru. */
- kthread_bind(cpu_rq(cpu)->migration_thread,smp_processor_id());
+ kthread_bind(cpu_rq(cpu)->migration_thread,
+ any_online_cpu(cpu_online_map));
kthread_stop(cpu_rq(cpu)->migration_thread);
cpu_rq(cpu)->migration_thread = NULL;
break;
projects / powerpc.git / blobdiff