*/
struct list_head leaf_cfs_rq_list;
struct task_group *tg; /* group that "owns" this runqueue */
-
-#ifdef CONFIG_SMP
- unsigned long task_weight;
- unsigned long shares;
- /*
- * We need space to build a sched_domain wide view of the full task
- * group tree, in order to avoid depending on dynamic memory allocation
- * during the load balancing we place this in the per cpu task group
- * hierarchy. This limits the load balancing to one instance per cpu,
- * but more should not be needed anyway.
- */
- struct aggregate_struct {
- /*
- * load = weight(cpus) * f(tg)
- *
- * Where f(tg) is the recursive weight fraction assigned to
- * this group.
- */
- unsigned long load;
-
- /*
- * part of the group weight distributed to this span.
- */
- unsigned long shares;
-
- /*
- * The sum of all runqueue weights within this span.
- */
- unsigned long rq_weight;
-
- /*
- * Weight contributed by tasks; this is the part we can
- * influence by moving tasks around.
- */
- unsigned long task_weight;
- } aggregate;
-#endif
#endif
};
static unsigned long target_load(int cpu, int type);
static unsigned long cpu_avg_load_per_task(int cpu);
static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd);
-
-#ifdef CONFIG_FAIR_GROUP_SCHED
-
-/*
- * Group load balancing.
- *
- * We calculate a few balance domain wide aggregate numbers; load and weight.
- * Given the pictures below, and assuming each item has equal weight:
- *
- * root 1 - thread
- * / | \ A - group
- * A 1 B
- * /|\ / \
- * C 2 D 3 4
- * | |
- * 5 6
- *
- * load:
- * A and B get 1/3-rd of the total load. C and D get 1/3-rd of A's 1/3-rd,
- * which equals 1/9-th of the total load.
- *
- * shares:
- * The weight of this group on the selected cpus.
- *
- * rq_weight:
- * Direct sum of all the cpu's their rq weight, e.g. A would get 3 while
- * B would get 2.
- *
- * task_weight:
- * Part of the rq_weight contributed by tasks; all groups except B would
- * get 1, B gets 2.
- */
-
-static inline struct aggregate_struct *
-aggregate(struct task_group *tg, struct sched_domain *sd)
-{
- return &tg->cfs_rq[sd->first_cpu]->aggregate;
-}
-
-typedef void (*aggregate_func)(struct task_group *, struct sched_domain *);
-
-/*
- * Iterate the full tree, calling @down when first entering a node and @up when
- * leaving it for the final time.
- */
-static
-void aggregate_walk_tree(aggregate_func down, aggregate_func up,
- struct sched_domain *sd)
-{
- struct task_group *parent, *child;
-
- rcu_read_lock();
- parent = &root_task_group;
-down:
- (*down)(parent, sd);
- list_for_each_entry_rcu(child, &parent->children, siblings) {
- parent = child;
- goto down;
-
-up:
- continue;
- }
- (*up)(parent, sd);
-
- child = parent;
- parent = parent->parent;
- if (parent)
- goto up;
- rcu_read_unlock();
-}
-
-/*
- * Calculate the aggregate runqueue weight.
- */
-static
-void aggregate_group_weight(struct task_group *tg, struct sched_domain *sd)
-{
- unsigned long rq_weight = 0;
- unsigned long task_weight = 0;
- int i;
-
- for_each_cpu_mask(i, sd->span) {
- rq_weight += tg->cfs_rq[i]->load.weight;
- task_weight += tg->cfs_rq[i]->task_weight;
- }
-
- aggregate(tg, sd)->rq_weight = rq_weight;
- aggregate(tg, sd)->task_weight = task_weight;
-}
-
-/*
- * Compute the weight of this group on the given cpus.
- */
-static
-void aggregate_group_shares(struct task_group *tg, struct sched_domain *sd)
-{
- unsigned long shares = 0;
- int i;
-
- for_each_cpu_mask(i, sd->span)
- shares += tg->cfs_rq[i]->shares;
-
- if ((!shares && aggregate(tg, sd)->rq_weight) || shares > tg->shares)
- shares = tg->shares;
-
- aggregate(tg, sd)->shares = shares;
-}
-
-/*
- * Compute the load fraction assigned to this group, relies on the aggregate
- * weight and this group's parent's load, i.e. top-down.
- */
-static
-void aggregate_group_load(struct task_group *tg, struct sched_domain *sd)
-{
- unsigned long load;
-
- if (!tg->parent) {
- int i;
-
- load = 0;
- for_each_cpu_mask(i, sd->span)
- load += cpu_rq(i)->load.weight;
-
- } else {
- load = aggregate(tg->parent, sd)->load;
-
- /*
- * shares is our weight in the parent's rq so
- * shares/parent->rq_weight gives our fraction of the load
- */
- load *= aggregate(tg, sd)->shares;
- load /= aggregate(tg->parent, sd)->rq_weight + 1;
- }
-
- aggregate(tg, sd)->load = load;
-}
-
-static void __set_se_shares(struct sched_entity *se, unsigned long shares);
-
-/*
- * Calculate and set the cpu's group shares.
- */
-static void
-__update_group_shares_cpu(struct task_group *tg, struct sched_domain *sd,
- int tcpu)
-{
- int boost = 0;
- unsigned long shares;
- unsigned long rq_weight;
-
- if (!tg->se[tcpu])
- return;
-
- rq_weight = tg->cfs_rq[tcpu]->load.weight;
-
- /*
- * If there are currently no tasks on the cpu pretend there is one of
- * average load so that when a new task gets to run here it will not
- * get delayed by group starvation.
- */
- if (!rq_weight) {
- boost = 1;
- rq_weight = NICE_0_LOAD;
- }
-
- /*
- * \Sum shares * rq_weight
- * shares = -----------------------
- * \Sum rq_weight
- *
- */
- shares = aggregate(tg, sd)->shares * rq_weight;
- shares /= aggregate(tg, sd)->rq_weight + 1;
-
- /*
- * record the actual number of shares, not the boosted amount.
- */
- tg->cfs_rq[tcpu]->shares = boost ? 0 : shares;
-
- if (shares < MIN_SHARES)
- shares = MIN_SHARES;
- else if (shares > MAX_SHARES)
- shares = MAX_SHARES;
-
- __set_se_shares(tg->se[tcpu], shares);
-}
-
-/*
- * Re-adjust the weights on the cpu the task came from and on the cpu the
- * task went to.
- */
-static void
-__move_group_shares(struct task_group *tg, struct sched_domain *sd,
- int scpu, int dcpu)
-{
- unsigned long shares;
-
- shares = tg->cfs_rq[scpu]->shares + tg->cfs_rq[dcpu]->shares;
-
- __update_group_shares_cpu(tg, sd, scpu);
- __update_group_shares_cpu(tg, sd, dcpu);
-
- /*
- * ensure we never loose shares due to rounding errors in the
- * above redistribution.
- */
- shares -= tg->cfs_rq[scpu]->shares + tg->cfs_rq[dcpu]->shares;
- if (shares)
- tg->cfs_rq[dcpu]->shares += shares;
-}
-
-/*
- * Because changing a group's shares changes the weight of the super-group
- * we need to walk up the tree and change all shares until we hit the root.
- */
-static void
-move_group_shares(struct task_group *tg, struct sched_domain *sd,
- int scpu, int dcpu)
-{
- while (tg) {
- __move_group_shares(tg, sd, scpu, dcpu);
- tg = tg->parent;
- }
-}
-
-static
-void aggregate_group_set_shares(struct task_group *tg, struct sched_domain *sd)
-{
- unsigned long shares = aggregate(tg, sd)->shares;
- int i;
-
- for_each_cpu_mask(i, sd->span) {
- struct rq *rq = cpu_rq(i);
- unsigned long flags;
-
- spin_lock_irqsave(&rq->lock, flags);
- __update_group_shares_cpu(tg, sd, i);
- spin_unlock_irqrestore(&rq->lock, flags);
- }
-
- aggregate_group_shares(tg, sd);
-
- /*
- * ensure we never loose shares due to rounding errors in the
- * above redistribution.
- */
- shares -= aggregate(tg, sd)->shares;
- if (shares) {
- tg->cfs_rq[sd->first_cpu]->shares += shares;
- aggregate(tg, sd)->shares += shares;
- }
-}
-
-/*
- * Calculate the accumulative weight and recursive load of each task group
- * while walking down the tree.
- */
-static
-void aggregate_get_down(struct task_group *tg, struct sched_domain *sd)
-{
- aggregate_group_weight(tg, sd);
- aggregate_group_shares(tg, sd);
- aggregate_group_load(tg, sd);
-}
-
-/*
- * Rebalance the cpu shares while walking back up the tree.
- */
-static
-void aggregate_get_up(struct task_group *tg, struct sched_domain *sd)
-{
- aggregate_group_set_shares(tg, sd);
-}
-
-static DEFINE_PER_CPU(spinlock_t, aggregate_lock);
-
-static void __init init_aggregate(void)
-{
- int i;
-
- for_each_possible_cpu(i)
- spin_lock_init(&per_cpu(aggregate_lock, i));
-}
-
-static int get_aggregate(struct sched_domain *sd)
-{
- if (!spin_trylock(&per_cpu(aggregate_lock, sd->first_cpu)))
- return 0;
-
- aggregate_walk_tree(aggregate_get_down, aggregate_get_up, sd);
- return 1;
-}
-
-static void put_aggregate(struct sched_domain *sd)
-{
- spin_unlock(&per_cpu(aggregate_lock, sd->first_cpu));
-}
-
-static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
-{
- cfs_rq->shares = shares;
-}
-
-#else
-
-static inline void init_aggregate(void)
-{
-}
-
-static inline int get_aggregate(struct sched_domain *sd)
-{
- return 0;
-}
-
-static inline void put_aggregate(struct sched_domain *sd)
-{
-}
-#endif
-
#else /* CONFIG_SMP */
#ifdef CONFIG_FAIR_GROUP_SCHED
#define sched_class_highest (&rt_sched_class)
-static void inc_nr_running(struct rq *rq)
+static inline void inc_load(struct rq *rq, const struct task_struct *p)
+{
+ update_load_add(&rq->load, p->se.load.weight);
+}
+
+static inline void dec_load(struct rq *rq, const struct task_struct *p)
+{
+ update_load_sub(&rq->load, p->se.load.weight);
+}
+
+static void inc_nr_running(struct task_struct *p, struct rq *rq)
{
rq->nr_running++;
+ inc_load(rq, p);
}
-static void dec_nr_running(struct rq *rq)
+static void dec_nr_running(struct task_struct *p, struct rq *rq)
{
rq->nr_running--;
+ dec_load(rq, p);
}
static void set_load_weight(struct task_struct *p)
rq->nr_uninterruptible--;
enqueue_task(rq, p, wakeup);
- inc_nr_running(rq);
+ inc_nr_running(p, rq);
}
/*
rq->nr_uninterruptible++;
dequeue_task(rq, p, sleep);
- dec_nr_running(rq);
+ dec_nr_running(p, rq);
}
/**
* management (if any):
*/
p->sched_class->task_new(rq, p);
- inc_nr_running(rq);
+ inc_nr_running(p, rq);
}
check_preempt_curr(rq, p);
#ifdef CONFIG_SMP
unsigned long imbalance;
struct rq *busiest;
unsigned long flags;
- int unlock_aggregate;
cpus_setall(*cpus);
- unlock_aggregate = get_aggregate(sd);
-
/*
* When power savings policy is enabled for the parent domain, idle
* sibling can pick up load irrespective of busy siblings. In this case,
if (!ld_moved && !sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
!test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
- ld_moved = -1;
-
- goto out;
+ return -1;
+ return ld_moved;
out_balanced:
schedstat_inc(sd, lb_balanced[idle]);
if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
!test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
- ld_moved = -1;
- else
- ld_moved = 0;
-out:
- if (unlock_aggregate)
- put_aggregate(sd);
- return ld_moved;
+ return -1;
+ return 0;
}
/*
goto out_unlock;
}
on_rq = p->se.on_rq;
- if (on_rq)
+ if (on_rq) {
dequeue_task(rq, p, 0);
+ dec_load(rq, p);
+ }
p->static_prio = NICE_TO_PRIO(nice);
set_load_weight(p);
if (on_rq) {
enqueue_task(rq, p, 0);
+ inc_load(rq, p);
/*
* If the task increased its priority or is running and
* lowered its priority, then reschedule its CPU:
SD_INIT(sd, ALLNODES);
set_domain_attribute(sd, attr);
sd->span = *cpu_map;
- sd->first_cpu = first_cpu(sd->span);
cpu_to_allnodes_group(i, cpu_map, &sd->groups, tmpmask);
p = sd;
sd_allnodes = 1;
SD_INIT(sd, NODE);
set_domain_attribute(sd, attr);
sched_domain_node_span(cpu_to_node(i), &sd->span);
- sd->first_cpu = first_cpu(sd->span);
sd->parent = p;
if (p)
p->child = sd;
SD_INIT(sd, CPU);
set_domain_attribute(sd, attr);
sd->span = *nodemask;
- sd->first_cpu = first_cpu(sd->span);
sd->parent = p;
if (p)
p->child = sd;
SD_INIT(sd, MC);
set_domain_attribute(sd, attr);
sd->span = cpu_coregroup_map(i);
- sd->first_cpu = first_cpu(sd->span);
cpus_and(sd->span, sd->span, *cpu_map);
sd->parent = p;
p->child = sd;
SD_INIT(sd, SIBLING);
set_domain_attribute(sd, attr);
sd->span = per_cpu(cpu_sibling_map, i);
- sd->first_cpu = first_cpu(sd->span);
cpus_and(sd->span, sd->span, *cpu_map);
sd->parent = p;
p->child = sd;
}
#ifdef CONFIG_SMP
- init_aggregate();
init_defrootdomain();
#endif
#endif
#ifdef CONFIG_FAIR_GROUP_SCHED
-static void __set_se_shares(struct sched_entity *se, unsigned long shares)
+static void set_se_shares(struct sched_entity *se, unsigned long shares)
{
struct cfs_rq *cfs_rq = se->cfs_rq;
+ struct rq *rq = cfs_rq->rq;
int on_rq;
+ spin_lock_irq(&rq->lock);
+
on_rq = se->on_rq;
if (on_rq)
dequeue_entity(cfs_rq, se, 0);
if (on_rq)
enqueue_entity(cfs_rq, se, 0);
-}
-static void set_se_shares(struct sched_entity *se, unsigned long shares)
-{
- struct cfs_rq *cfs_rq = se->cfs_rq;
- struct rq *rq = cfs_rq->rq;
- unsigned long flags;
-
- spin_lock_irqsave(&rq->lock, flags);
- __set_se_shares(se, shares);
- spin_unlock_irqrestore(&rq->lock, flags);
+ spin_unlock_irq(&rq->lock);
}
static DEFINE_MUTEX(shares_mutex);
* w/o tripping rebalance_share or load_balance_fair.
*/
tg->shares = shares;
- for_each_possible_cpu(i) {
- /*
- * force a rebalance
- */
- cfs_rq_set_shares(tg->cfs_rq[i], 0);
+ for_each_possible_cpu(i)
set_se_shares(tg->se[i], shares);
- }
/*
* Enable load balance activity on this group, by inserting it back on
* Scheduling class queueing methods:
*/
-#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED
-static void
-add_cfs_task_weight(struct cfs_rq *cfs_rq, unsigned long weight)
-{
- cfs_rq->task_weight += weight;
-}
-#else
-static inline void
-add_cfs_task_weight(struct cfs_rq *cfs_rq, unsigned long weight)
-{
-}
-#endif
-
static void
account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
update_load_add(&cfs_rq->load, se->load.weight);
- if (!parent_entity(se))
- inc_cpu_load(rq_of(cfs_rq), se->load.weight);
- if (entity_is_task(se))
- 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);
account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
update_load_sub(&cfs_rq->load, se->load.weight);
- if (!parent_entity(se))
- dec_cpu_load(rq_of(cfs_rq), se->load.weight);
- if (entity_is_task(se))
- add_cfs_task_weight(cfs_rq, -se->load.weight);
cfs_rq->nr_running--;
se->on_rq = 0;
list_del_init(&se->group_node);
return __load_balance_iterator(cfs_rq, cfs_rq->balance_iterator);
}
-static unsigned long
-__load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
- unsigned long max_load_move, struct sched_domain *sd,
- enum cpu_idle_type idle, int *all_pinned, int *this_best_prio,
- struct cfs_rq *cfs_rq)
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static int cfs_rq_best_prio(struct cfs_rq *cfs_rq)
{
- struct rq_iterator cfs_rq_iterator;
+ struct sched_entity *curr;
+ struct task_struct *p;
- cfs_rq_iterator.start = load_balance_start_fair;
- cfs_rq_iterator.next = load_balance_next_fair;
- cfs_rq_iterator.arg = cfs_rq;
+ if (!cfs_rq->nr_running || !first_fair(cfs_rq))
+ return MAX_PRIO;
+
+ curr = cfs_rq->curr;
+ if (!curr)
+ curr = __pick_next_entity(cfs_rq);
- return balance_tasks(this_rq, this_cpu, busiest,
- max_load_move, sd, idle, all_pinned,
- this_best_prio, &cfs_rq_iterator);
+ p = task_of(curr);
+
+ return p->prio;
}
+#endif
-#ifdef CONFIG_FAIR_GROUP_SCHED
static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move,
struct sched_domain *sd, enum cpu_idle_type idle,
int *all_pinned, int *this_best_prio)
{
+ struct cfs_rq *busy_cfs_rq;
long rem_load_move = max_load_move;
- int busiest_cpu = cpu_of(busiest);
- struct task_group *tg;
-
- rcu_read_lock();
- list_for_each_entry(tg, &task_groups, list) {
- long imbalance;
- unsigned long this_weight, busiest_weight;
- long rem_load, max_load, moved_load;
-
- /*
- * empty group
- */
- if (!aggregate(tg, sd)->task_weight)
- continue;
-
- rem_load = rem_load_move * aggregate(tg, sd)->rq_weight;
- rem_load /= aggregate(tg, sd)->load + 1;
-
- this_weight = tg->cfs_rq[this_cpu]->task_weight;
- busiest_weight = tg->cfs_rq[busiest_cpu]->task_weight;
+ struct rq_iterator cfs_rq_iterator;
- imbalance = (busiest_weight - this_weight) / 2;
+ cfs_rq_iterator.start = load_balance_start_fair;
+ cfs_rq_iterator.next = load_balance_next_fair;
- if (imbalance < 0)
- imbalance = busiest_weight;
+ for_each_leaf_cfs_rq(busiest, busy_cfs_rq) {
+#ifdef CONFIG_FAIR_GROUP_SCHED
+ struct cfs_rq *this_cfs_rq;
+ long imbalance;
+ unsigned long maxload;
- max_load = max(rem_load, imbalance);
- moved_load = __load_balance_fair(this_rq, this_cpu, busiest,
- max_load, sd, idle, all_pinned, this_best_prio,
- tg->cfs_rq[busiest_cpu]);
+ this_cfs_rq = cpu_cfs_rq(busy_cfs_rq, this_cpu);
- if (!moved_load)
+ imbalance = busy_cfs_rq->load.weight - this_cfs_rq->load.weight;
+ /* Don't pull if this_cfs_rq has more load than busy_cfs_rq */
+ if (imbalance <= 0)
continue;
- move_group_shares(tg, sd, busiest_cpu, this_cpu);
+ /* Don't pull more than imbalance/2 */
+ imbalance /= 2;
+ maxload = min(rem_load_move, imbalance);
- moved_load *= aggregate(tg, sd)->load;
- moved_load /= aggregate(tg, sd)->rq_weight + 1;
+ *this_best_prio = cfs_rq_best_prio(this_cfs_rq);
+#else
+# define maxload rem_load_move
+#endif
+ /*
+ * pass busy_cfs_rq argument into
+ * load_balance_[start|next]_fair iterators
+ */
+ cfs_rq_iterator.arg = busy_cfs_rq;
+ rem_load_move -= balance_tasks(this_rq, this_cpu, busiest,
+ maxload, sd, idle, all_pinned,
+ this_best_prio,
+ &cfs_rq_iterator);
- rem_load_move -= moved_load;
- if (rem_load_move < 0)
+ if (rem_load_move <= 0)
break;
}
- rcu_read_unlock();
return max_load_move - rem_load_move;
}
-#else
-static unsigned long
-load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
- unsigned long max_load_move,
- struct sched_domain *sd, enum cpu_idle_type idle,
- int *all_pinned, int *this_best_prio)
-{
- return __load_balance_fair(this_rq, this_cpu, busiest,
- max_load_move, sd, idle, all_pinned,
- this_best_prio, &busiest->cfs);
-}
-#endif
static int
move_one_task_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
projects / linux-2.6 / commitdiff