}
#endif
+/*
+ * delta *= w / rw
+ */
+static inline unsigned long
+calc_delta_weight(unsigned long delta, struct sched_entity *se)
+{
+ for_each_sched_entity(se) {
+ delta = calc_delta_mine(delta,
+ se->load.weight, &cfs_rq_of(se)->load);
+ }
+
+ return delta;
+}
+
+/*
+ * delta *= rw / w
+ */
+static inline unsigned long
+calc_delta_fair(unsigned long delta, struct sched_entity *se)
+{
+ for_each_sched_entity(se) {
+ delta = calc_delta_mine(delta,
+ cfs_rq_of(se)->load.weight, &se->load);
+ }
+
+ return delta;
+}
+
/*
* The idea is to set a period in which each task runs once.
*
*/
static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- u64 slice = __sched_period(cfs_rq->nr_running);
-
- for_each_sched_entity(se) {
- cfs_rq = cfs_rq_of(se);
-
- slice *= se->load.weight;
- do_div(slice, cfs_rq->load.weight);
- }
-
-
- return slice;
+ return calc_delta_weight(__sched_period(cfs_rq->nr_running), se);
}
/*
* We calculate the vruntime slice of a to be inserted task
*
- * vs = s/w = p/rw
+ * vs = s*rw/w = p
*/
static u64 sched_vslice_add(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
unsigned long nr_running = cfs_rq->nr_running;
- unsigned long weight;
- u64 vslice;
if (!se->on_rq)
nr_running++;
- vslice = __sched_period(nr_running);
+ return __sched_period(nr_running);
+}
+
+/*
+ * The goal of calc_delta_asym() is to be asymmetrically around NICE_0_LOAD, in
+ * that it favours >=0 over <0.
+ *
+ * -20 |
+ * |
+ * 0 --------+-------
+ * .'
+ * 19 .'
+ *
+ */
+static unsigned long
+calc_delta_asym(unsigned long delta, struct sched_entity *se)
+{
+ struct load_weight lw = {
+ .weight = NICE_0_LOAD,
+ .inv_weight = 1UL << (WMULT_SHIFT-NICE_0_SHIFT)
+ };
for_each_sched_entity(se) {
- cfs_rq = cfs_rq_of(se);
+ struct load_weight *se_lw = &se->load;
- weight = cfs_rq->load.weight;
- if (!se->on_rq)
- weight += se->load.weight;
+ if (se->load.weight < NICE_0_LOAD)
+ se_lw = &lw;
- vslice *= NICE_0_LOAD;
- do_div(vslice, weight);
+ delta = calc_delta_mine(delta,
+ cfs_rq_of(se)->load.weight, se_lw);
}
- return vslice;
+ return delta;
}
/*
curr->sum_exec_runtime += delta_exec;
schedstat_add(cfs_rq, exec_clock, delta_exec);
- delta_exec_weighted = delta_exec;
- if (unlikely(curr->load.weight != NICE_0_LOAD)) {
- delta_exec_weighted = calc_delta_fair(delta_exec_weighted,
- &curr->load);
- }
+ delta_exec_weighted = calc_delta_fair(delta_exec, curr);
curr->vruntime += delta_exec_weighted;
}
add_cfs_task_weight(cfs_rq, se->load.weight);
cfs_rq->nr_running++;
se->on_rq = 1;
+ list_add(&se->group_node, &cfs_rq->tasks);
}
static void
add_cfs_task_weight(cfs_rq, -se->load.weight);
cfs_rq->nr_running--;
se->on_rq = 0;
+ list_del_init(&se->group_node);
}
static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
/* sleeps upto a single latency don't count. */
if (sched_feat(NEW_FAIR_SLEEPERS)) {
if (sched_feat(NORMALIZED_SLEEPER))
- vruntime -= calc_delta_fair(sysctl_sched_latency,
- &cfs_rq->load);
+ vruntime -= calc_delta_weight(sysctl_sched_latency, se);
else
vruntime -= sysctl_sched_latency;
}
unsigned long gran = sysctl_sched_wakeup_granularity;
/*
- * More easily preempt - nice tasks, while not making
- * it harder for + nice tasks.
+ * More easily preempt - nice tasks, while not making it harder for
+ * + nice tasks.
*/
- if (unlikely(se->load.weight > NICE_0_LOAD))
- gran = calc_delta_fair(gran, &se->load);
+ gran = calc_delta_asym(sysctl_sched_wakeup_granularity, se);
return gran;
}
* the current task:
*/
static struct task_struct *
-__load_balance_iterator(struct cfs_rq *cfs_rq, struct rb_node *curr)
+__load_balance_iterator(struct cfs_rq *cfs_rq, struct list_head *next)
{
struct task_struct *p = NULL;
struct sched_entity *se;
- if (!curr)
+ if (next == &cfs_rq->tasks)
return NULL;
/* Skip over entities that are not tasks */
do {
- se = rb_entry(curr, struct sched_entity, run_node);
- curr = rb_next(curr);
- } while (curr && !entity_is_task(se));
+ se = list_entry(next, struct sched_entity, group_node);
+ next = next->next;
+ } while (next != &cfs_rq->tasks && !entity_is_task(se));
- cfs_rq->rb_load_balance_curr = curr;
+ if (next == &cfs_rq->tasks)
+ return NULL;
+
+ cfs_rq->balance_iterator = next;
if (entity_is_task(se))
p = task_of(se);
{
struct cfs_rq *cfs_rq = arg;
- return __load_balance_iterator(cfs_rq, first_fair(cfs_rq));
+ return __load_balance_iterator(cfs_rq, cfs_rq->tasks.next);
}
static struct task_struct *load_balance_next_fair(void *arg)
{
struct cfs_rq *cfs_rq = arg;
- return __load_balance_iterator(cfs_rq, cfs_rq->rb_load_balance_curr);
+ return __load_balance_iterator(cfs_rq, cfs_rq->balance_iterator);
}
static unsigned long
};
#ifdef CONFIG_SCHED_DEBUG
+static void
+print_cfs_rq_tasks(struct seq_file *m, struct cfs_rq *cfs_rq, int depth)
+{
+ struct sched_entity *se;
+
+ if (!cfs_rq)
+ return;
+
+ list_for_each_entry_rcu(se, &cfs_rq->tasks, group_node) {
+ int i;
+
+ for (i = depth; i; i--)
+ seq_puts(m, " ");
+
+ seq_printf(m, "%lu %s %lu\n",
+ se->load.weight,
+ entity_is_task(se) ? "T" : "G",
+ calc_delta_weight(SCHED_LOAD_SCALE, se)
+ );
+ if (!entity_is_task(se))
+ print_cfs_rq_tasks(m, group_cfs_rq(se), depth + 1);
+ }
+}
+
static void print_cfs_stats(struct seq_file *m, int cpu)
{
struct cfs_rq *cfs_rq;
rcu_read_lock();
for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
print_cfs_rq(m, cpu, cfs_rq);
+
+ seq_printf(m, "\nWeight tree:\n");
+ print_cfs_rq_tasks(m, &cpu_rq(cpu)->cfs, 1);
rcu_read_unlock();
}
#endif