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authorPeter Zijlstra <a.p.zijlstra@chello.nl>2011-10-25 10:00:11 +0200
committerIngo Molnar <mingo@elte.hu>2011-11-17 12:20:19 +0100
commit029632fbb7b7c9d85063cc9eb470de6c54873df3 (patch)
tree511303f0fa32f997c4b2f68364b032555b6a642e /kernel/sched_fair.c
parent60686317da05049385eae86e44c710cde535f95f (diff)
downloadlinux-linaro-stable-029632fbb7b7c9d85063cc9eb470de6c54873df3.tar.gz
sched: Make separate sched*.c translation units
Since once needs to do something at conferences and fixing compile warnings doesn't actually require much if any attention I decided to break up the sched.c #include "*.c" fest. This further modularizes the scheduler code. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-x0fcd3mnp8f9c99grcpewmhi@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/sched_fair.c')
-rw-r--r--kernel/sched_fair.c580
1 files changed, 542 insertions, 38 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index a608593df243..cd3b64219d9f 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -23,6 +23,13 @@
#include <linux/latencytop.h>
#include <linux/sched.h>
#include <linux/cpumask.h>
+#include <linux/slab.h>
+#include <linux/profile.h>
+#include <linux/interrupt.h>
+
+#include <trace/events/sched.h>
+
+#include "sched.h"
/*
* Targeted preemption latency for CPU-bound tasks:
@@ -103,7 +110,110 @@ unsigned int __read_mostly sysctl_sched_shares_window = 10000000UL;
unsigned int sysctl_sched_cfs_bandwidth_slice = 5000UL;
#endif
-static const struct sched_class fair_sched_class;
+/*
+ * Increase the granularity value when there are more CPUs,
+ * because with more CPUs the 'effective latency' as visible
+ * to users decreases. But the relationship is not linear,
+ * so pick a second-best guess by going with the log2 of the
+ * number of CPUs.
+ *
+ * This idea comes from the SD scheduler of Con Kolivas:
+ */
+static int get_update_sysctl_factor(void)
+{
+ unsigned int cpus = min_t(int, num_online_cpus(), 8);
+ unsigned int factor;
+
+ switch (sysctl_sched_tunable_scaling) {
+ case SCHED_TUNABLESCALING_NONE:
+ factor = 1;
+ break;
+ case SCHED_TUNABLESCALING_LINEAR:
+ factor = cpus;
+ break;
+ case SCHED_TUNABLESCALING_LOG:
+ default:
+ factor = 1 + ilog2(cpus);
+ break;
+ }
+
+ return factor;
+}
+
+static void update_sysctl(void)
+{
+ unsigned int factor = get_update_sysctl_factor();
+
+#define SET_SYSCTL(name) \
+ (sysctl_##name = (factor) * normalized_sysctl_##name)
+ SET_SYSCTL(sched_min_granularity);
+ SET_SYSCTL(sched_latency);
+ SET_SYSCTL(sched_wakeup_granularity);
+#undef SET_SYSCTL
+}
+
+void sched_init_granularity(void)
+{
+ update_sysctl();
+}
+
+#if BITS_PER_LONG == 32
+# define WMULT_CONST (~0UL)
+#else
+# define WMULT_CONST (1UL << 32)
+#endif
+
+#define WMULT_SHIFT 32
+
+/*
+ * Shift right and round:
+ */
+#define SRR(x, y) (((x) + (1UL << ((y) - 1))) >> (y))
+
+/*
+ * delta *= weight / lw
+ */
+static unsigned long
+calc_delta_mine(unsigned long delta_exec, unsigned long weight,
+ struct load_weight *lw)
+{
+ u64 tmp;
+
+ /*
+ * weight can be less than 2^SCHED_LOAD_RESOLUTION for task group sched
+ * entities since MIN_SHARES = 2. Treat weight as 1 if less than
+ * 2^SCHED_LOAD_RESOLUTION.
+ */
+ if (likely(weight > (1UL << SCHED_LOAD_RESOLUTION)))
+ tmp = (u64)delta_exec * scale_load_down(weight);
+ else
+ tmp = (u64)delta_exec;
+
+ if (!lw->inv_weight) {
+ unsigned long w = scale_load_down(lw->weight);
+
+ if (BITS_PER_LONG > 32 && unlikely(w >= WMULT_CONST))
+ lw->inv_weight = 1;
+ else if (unlikely(!w))
+ lw->inv_weight = WMULT_CONST;
+ else
+ lw->inv_weight = WMULT_CONST / w;
+ }
+
+ /*
+ * Check whether we'd overflow the 64-bit multiplication:
+ */
+ if (unlikely(tmp > WMULT_CONST))
+ tmp = SRR(SRR(tmp, WMULT_SHIFT/2) * lw->inv_weight,
+ WMULT_SHIFT/2);
+ else
+ tmp = SRR(tmp * lw->inv_weight, WMULT_SHIFT);
+
+ return (unsigned long)min(tmp, (u64)(unsigned long)LONG_MAX);
+}
+
+
+const struct sched_class fair_sched_class;
/**************************************************************
* CFS operations on generic schedulable entities:
@@ -413,7 +523,7 @@ static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
rb_erase(&se->run_node, &cfs_rq->tasks_timeline);
}
-static struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq)
+struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq)
{
struct rb_node *left = cfs_rq->rb_leftmost;
@@ -434,7 +544,7 @@ static struct sched_entity *__pick_next_entity(struct sched_entity *se)
}
#ifdef CONFIG_SCHED_DEBUG
-static struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
+struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
{
struct rb_node *last = rb_last(&cfs_rq->tasks_timeline);
@@ -684,7 +794,7 @@ 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);
+ update_load_add(&rq_of(cfs_rq)->load, se->load.weight);
if (entity_is_task(se)) {
add_cfs_task_weight(cfs_rq, se->load.weight);
list_add(&se->group_node, &cfs_rq->tasks);
@@ -697,7 +807,7 @@ 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);
+ update_load_sub(&rq_of(cfs_rq)->load, se->load.weight);
if (entity_is_task(se)) {
add_cfs_task_weight(cfs_rq, -se->load.weight);
list_del_init(&se->group_node);
@@ -1287,6 +1397,32 @@ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
*/
#ifdef CONFIG_CFS_BANDWIDTH
+
+#ifdef HAVE_JUMP_LABEL
+static struct jump_label_key __cfs_bandwidth_used;
+
+static inline bool cfs_bandwidth_used(void)
+{
+ return static_branch(&__cfs_bandwidth_used);
+}
+
+void account_cfs_bandwidth_used(int enabled, int was_enabled)
+{
+ /* only need to count groups transitioning between enabled/!enabled */
+ if (enabled && !was_enabled)
+ jump_label_inc(&__cfs_bandwidth_used);
+ else if (!enabled && was_enabled)
+ jump_label_dec(&__cfs_bandwidth_used);
+}
+#else /* HAVE_JUMP_LABEL */
+static bool cfs_bandwidth_used(void)
+{
+ return true;
+}
+
+void account_cfs_bandwidth_used(int enabled, int was_enabled) {}
+#endif /* HAVE_JUMP_LABEL */
+
/*
* default period for cfs group bandwidth.
* default: 0.1s, units: nanoseconds
@@ -1308,7 +1444,7 @@ static inline u64 sched_cfs_bandwidth_slice(void)
*
* requires cfs_b->lock
*/
-static void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b)
+void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b)
{
u64 now;
@@ -1320,6 +1456,11 @@ static void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b)
cfs_b->runtime_expires = now + ktime_to_ns(cfs_b->period);
}
+static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
+{
+ return &tg->cfs_bandwidth;
+}
+
/* returns 0 on failure to allocate runtime */
static int assign_cfs_rq_runtime(struct cfs_rq *cfs_rq)
{
@@ -1530,7 +1671,7 @@ static void throttle_cfs_rq(struct cfs_rq *cfs_rq)
raw_spin_unlock(&cfs_b->lock);
}
-static void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
+void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
{
struct rq *rq = rq_of(cfs_rq);
struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
@@ -1839,7 +1980,112 @@ static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq)
throttle_cfs_rq(cfs_rq);
}
-#else
+
+static inline u64 default_cfs_period(void);
+static int do_sched_cfs_period_timer(struct cfs_bandwidth *cfs_b, int overrun);
+static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b);
+
+static enum hrtimer_restart sched_cfs_slack_timer(struct hrtimer *timer)
+{
+ struct cfs_bandwidth *cfs_b =
+ container_of(timer, struct cfs_bandwidth, slack_timer);
+ do_sched_cfs_slack_timer(cfs_b);
+
+ return HRTIMER_NORESTART;
+}
+
+static enum hrtimer_restart sched_cfs_period_timer(struct hrtimer *timer)
+{
+ struct cfs_bandwidth *cfs_b =
+ container_of(timer, struct cfs_bandwidth, period_timer);
+ ktime_t now;
+ int overrun;
+ int idle = 0;
+
+ for (;;) {
+ now = hrtimer_cb_get_time(timer);
+ overrun = hrtimer_forward(timer, now, cfs_b->period);
+
+ if (!overrun)
+ break;
+
+ idle = do_sched_cfs_period_timer(cfs_b, overrun);
+ }
+
+ return idle ? HRTIMER_NORESTART : HRTIMER_RESTART;
+}
+
+void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
+{
+ raw_spin_lock_init(&cfs_b->lock);
+ cfs_b->runtime = 0;
+ cfs_b->quota = RUNTIME_INF;
+ cfs_b->period = ns_to_ktime(default_cfs_period());
+
+ INIT_LIST_HEAD(&cfs_b->throttled_cfs_rq);
+ hrtimer_init(&cfs_b->period_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ cfs_b->period_timer.function = sched_cfs_period_timer;
+ hrtimer_init(&cfs_b->slack_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ cfs_b->slack_timer.function = sched_cfs_slack_timer;
+}
+
+static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq)
+{
+ cfs_rq->runtime_enabled = 0;
+ INIT_LIST_HEAD(&cfs_rq->throttled_list);
+}
+
+/* requires cfs_b->lock, may release to reprogram timer */
+void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
+{
+ /*
+ * The timer may be active because we're trying to set a new bandwidth
+ * period or because we're racing with the tear-down path
+ * (timer_active==0 becomes visible before the hrtimer call-back
+ * terminates). In either case we ensure that it's re-programmed
+ */
+ while (unlikely(hrtimer_active(&cfs_b->period_timer))) {
+ raw_spin_unlock(&cfs_b->lock);
+ /* ensure cfs_b->lock is available while we wait */
+ hrtimer_cancel(&cfs_b->period_timer);
+
+ raw_spin_lock(&cfs_b->lock);
+ /* if someone else restarted the timer then we're done */
+ if (cfs_b->timer_active)
+ return;
+ }
+
+ cfs_b->timer_active = 1;
+ start_bandwidth_timer(&cfs_b->period_timer, cfs_b->period);
+}
+
+static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
+{
+ hrtimer_cancel(&cfs_b->period_timer);
+ hrtimer_cancel(&cfs_b->slack_timer);
+}
+
+void unthrottle_offline_cfs_rqs(struct rq *rq)
+{
+ struct cfs_rq *cfs_rq;
+
+ for_each_leaf_cfs_rq(rq, cfs_rq) {
+ struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
+
+ if (!cfs_rq->runtime_enabled)
+ continue;
+
+ /*
+ * clock_task is not advancing so we just need to make sure
+ * there's some valid quota amount
+ */
+ cfs_rq->runtime_remaining = cfs_b->quota;
+ if (cfs_rq_throttled(cfs_rq))
+ unthrottle_cfs_rq(cfs_rq);
+ }
+}
+
+#else /* CONFIG_CFS_BANDWIDTH */
static void account_cfs_rq_runtime(struct cfs_rq *cfs_rq,
unsigned long delta_exec) {}
static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
@@ -1861,8 +2107,22 @@ static inline int throttled_lb_pair(struct task_group *tg,
{
return 0;
}
+
+void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
#endif
+static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
+{
+ return NULL;
+}
+static inline void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
+void unthrottle_offline_cfs_rqs(struct rq *rq) {}
+
+#endif /* CONFIG_CFS_BANDWIDTH */
+
/**************************************************
* CFS operations on tasks:
*/
@@ -2029,6 +2289,61 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
}
#ifdef CONFIG_SMP
+/* Used instead of source_load when we know the type == 0 */
+static unsigned long weighted_cpuload(const int cpu)
+{
+ return cpu_rq(cpu)->load.weight;
+}
+
+/*
+ * Return a low guess at the load of a migration-source cpu weighted
+ * according to the scheduling class and "nice" value.
+ *
+ * We want to under-estimate the load of migration sources, to
+ * balance conservatively.
+ */
+static unsigned long source_load(int cpu, int type)
+{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long total = weighted_cpuload(cpu);
+
+ if (type == 0 || !sched_feat(LB_BIAS))
+ return total;
+
+ return min(rq->cpu_load[type-1], total);
+}
+
+/*
+ * Return a high guess at the load of a migration-target cpu weighted
+ * according to the scheduling class and "nice" value.
+ */
+static unsigned long target_load(int cpu, int type)
+{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long total = weighted_cpuload(cpu);
+
+ if (type == 0 || !sched_feat(LB_BIAS))
+ return total;
+
+ return max(rq->cpu_load[type-1], total);
+}
+
+static unsigned long power_of(int cpu)
+{
+ return cpu_rq(cpu)->cpu_power;
+}
+
+static unsigned long cpu_avg_load_per_task(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long nr_running = ACCESS_ONCE(rq->nr_running);
+
+ if (nr_running)
+ return rq->load.weight / nr_running;
+
+ return 0;
+}
+
static void task_waking_fair(struct task_struct *p)
{
@@ -2783,6 +3098,38 @@ static void pull_task(struct rq *src_rq, struct task_struct *p,
}
/*
+ * Is this task likely cache-hot:
+ */
+static int
+task_hot(struct task_struct *p, u64 now, struct sched_domain *sd)
+{
+ s64 delta;
+
+ if (p->sched_class != &fair_sched_class)
+ return 0;
+
+ if (unlikely(p->policy == SCHED_IDLE))
+ return 0;
+
+ /*
+ * Buddy candidates are cache hot:
+ */
+ if (sched_feat(CACHE_HOT_BUDDY) && this_rq()->nr_running &&
+ (&p->se == cfs_rq_of(&p->se)->next ||
+ &p->se == cfs_rq_of(&p->se)->last))
+ return 1;
+
+ if (sysctl_sched_migration_cost == -1)
+ return 1;
+ if (sysctl_sched_migration_cost == 0)
+ return 0;
+
+ delta = now - p->se.exec_start;
+
+ return delta < (s64)sysctl_sched_migration_cost;
+}
+
+/*
* can_migrate_task - may task p from runqueue rq be migrated to this_cpu?
*/
static
@@ -3162,15 +3509,6 @@ struct sg_lb_stats {
};
/**
- * group_first_cpu - Returns the first cpu in the cpumask of a sched_group.
- * @group: The group whose first cpu is to be returned.
- */
-static inline unsigned int group_first_cpu(struct sched_group *group)
-{
- return cpumask_first(sched_group_cpus(group));
-}
-
-/**
* get_sd_load_idx - Obtain the load index for a given sched domain.
* @sd: The sched_domain whose load_idx is to be obtained.
* @idle: The Idle status of the CPU for whose sd load_icx is obtained.
@@ -3419,7 +3757,7 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
sdg->sgp->power = power;
}
-static void update_group_power(struct sched_domain *sd, int cpu)
+void update_group_power(struct sched_domain *sd, int cpu)
{
struct sched_domain *child = sd->child;
struct sched_group *group, *sdg = sd->groups;
@@ -3685,11 +4023,6 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
} while (sg != sd->groups);
}
-int __weak arch_sd_sibling_asym_packing(void)
-{
- return 0*SD_ASYM_PACKING;
-}
-
/**
* check_asym_packing - Check to see if the group is packed into the
* sched doman.
@@ -4053,7 +4386,7 @@ find_busiest_queue(struct sched_domain *sd, struct sched_group *group,
#define MAX_PINNED_INTERVAL 512
/* Working cpumask for load_balance and load_balance_newidle. */
-static DEFINE_PER_CPU(cpumask_var_t, load_balance_tmpmask);
+DEFINE_PER_CPU(cpumask_var_t, load_balance_tmpmask);
static int need_active_balance(struct sched_domain *sd, int idle,
int busiest_cpu, int this_cpu)
@@ -4256,7 +4589,7 @@ out:
* idle_balance is called by schedule() if this_cpu is about to become
* idle. Attempts to pull tasks from other CPUs.
*/
-static void idle_balance(int this_cpu, struct rq *this_rq)
+void idle_balance(int this_cpu, struct rq *this_rq)
{
struct sched_domain *sd;
int pulled_task = 0;
@@ -4631,7 +4964,7 @@ static unsigned long __read_mostly max_load_balance_interval = HZ/10;
* Scale the max load_balance interval with the number of CPUs in the system.
* This trades load-balance latency on larger machines for less cross talk.
*/
-static void update_max_interval(void)
+void update_max_interval(void)
{
max_load_balance_interval = HZ*num_online_cpus()/10;
}
@@ -4833,7 +5166,7 @@ static inline int on_null_domain(int cpu)
/*
* Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
*/
-static inline void trigger_load_balance(struct rq *rq, int cpu)
+void trigger_load_balance(struct rq *rq, int cpu)
{
/* Don't need to rebalance while attached to NULL domain */
if (time_after_eq(jiffies, rq->next_balance) &&
@@ -4855,15 +5188,6 @@ static void rq_offline_fair(struct rq *rq)
update_sysctl();
}
-#else /* CONFIG_SMP */
-
-/*
- * on UP we do not need to balance between CPUs:
- */
-static inline void idle_balance(int cpu, struct rq *rq)
-{
-}
-
#endif /* CONFIG_SMP */
/*
@@ -5006,6 +5330,16 @@ static void set_curr_task_fair(struct rq *rq)
}
}
+void init_cfs_rq(struct cfs_rq *cfs_rq)
+{
+ cfs_rq->tasks_timeline = RB_ROOT;
+ INIT_LIST_HEAD(&cfs_rq->tasks);
+ cfs_rq->min_vruntime = (u64)(-(1LL << 20));
+#ifndef CONFIG_64BIT
+ cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
+#endif
+}
+
#ifdef CONFIG_FAIR_GROUP_SCHED
static void task_move_group_fair(struct task_struct *p, int on_rq)
{
@@ -5028,7 +5362,161 @@ static void task_move_group_fair(struct task_struct *p, int on_rq)
if (!on_rq)
p->se.vruntime += cfs_rq_of(&p->se)->min_vruntime;
}
+
+void free_fair_sched_group(struct task_group *tg)
+{
+ int i;
+
+ destroy_cfs_bandwidth(tg_cfs_bandwidth(tg));
+
+ for_each_possible_cpu(i) {
+ if (tg->cfs_rq)
+ kfree(tg->cfs_rq[i]);
+ if (tg->se)
+ kfree(tg->se[i]);
+ }
+
+ kfree(tg->cfs_rq);
+ kfree(tg->se);
+}
+
+int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
+{
+ struct cfs_rq *cfs_rq;
+ struct sched_entity *se;
+ int i;
+
+ tg->cfs_rq = kzalloc(sizeof(cfs_rq) * nr_cpu_ids, GFP_KERNEL);
+ if (!tg->cfs_rq)
+ goto err;
+ tg->se = kzalloc(sizeof(se) * nr_cpu_ids, GFP_KERNEL);
+ if (!tg->se)
+ goto err;
+
+ tg->shares = NICE_0_LOAD;
+
+ init_cfs_bandwidth(tg_cfs_bandwidth(tg));
+
+ for_each_possible_cpu(i) {
+ cfs_rq = kzalloc_node(sizeof(struct cfs_rq),
+ GFP_KERNEL, cpu_to_node(i));
+ if (!cfs_rq)
+ goto err;
+
+ se = kzalloc_node(sizeof(struct sched_entity),
+ GFP_KERNEL, cpu_to_node(i));
+ if (!se)
+ goto err_free_rq;
+
+ init_cfs_rq(cfs_rq);
+ init_tg_cfs_entry(tg, cfs_rq, se, i, parent->se[i]);
+ }
+
+ return 1;
+
+err_free_rq:
+ kfree(cfs_rq);
+err:
+ return 0;
+}
+
+void unregister_fair_sched_group(struct task_group *tg, int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long flags;
+
+ /*
+ * Only empty task groups can be destroyed; so we can speculatively
+ * check on_list without danger of it being re-added.
+ */
+ if (!tg->cfs_rq[cpu]->on_list)
+ return;
+
+ raw_spin_lock_irqsave(&rq->lock, flags);
+ list_del_leaf_cfs_rq(tg->cfs_rq[cpu]);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
+ struct sched_entity *se, int cpu,
+ struct sched_entity *parent)
+{
+ struct rq *rq = cpu_rq(cpu);
+
+ cfs_rq->tg = tg;
+ cfs_rq->rq = rq;
+#ifdef CONFIG_SMP
+ /* allow initial update_cfs_load() to truncate */
+ cfs_rq->load_stamp = 1;
#endif
+ init_cfs_rq_runtime(cfs_rq);
+
+ tg->cfs_rq[cpu] = cfs_rq;
+ tg->se[cpu] = se;
+
+ /* se could be NULL for root_task_group */
+ if (!se)
+ return;
+
+ if (!parent)
+ se->cfs_rq = &rq->cfs;
+ else
+ se->cfs_rq = parent->my_q;
+
+ se->my_q = cfs_rq;
+ update_load_set(&se->load, 0);
+ se->parent = parent;
+}
+
+static DEFINE_MUTEX(shares_mutex);
+
+int sched_group_set_shares(struct task_group *tg, unsigned long shares)
+{
+ int i;
+ unsigned long flags;
+
+ /*
+ * We can't change the weight of the root cgroup.
+ */
+ if (!tg->se[0])
+ return -EINVAL;
+
+ shares = clamp(shares, scale_load(MIN_SHARES), scale_load(MAX_SHARES));
+
+ mutex_lock(&shares_mutex);
+ if (tg->shares == shares)
+ goto done;
+
+ tg->shares = shares;
+ for_each_possible_cpu(i) {
+ struct rq *rq = cpu_rq(i);
+ struct sched_entity *se;
+
+ se = tg->se[i];
+ /* Propagate contribution to hierarchy */
+ raw_spin_lock_irqsave(&rq->lock, flags);
+ for_each_sched_entity(se)
+ update_cfs_shares(group_cfs_rq(se));
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
+ }
+
+done:
+ mutex_unlock(&shares_mutex);
+ return 0;
+}
+#else /* CONFIG_FAIR_GROUP_SCHED */
+
+void free_fair_sched_group(struct task_group *tg) { }
+
+int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
+{
+ return 1;
+}
+
+void unregister_fair_sched_group(struct task_group *tg, int cpu) { }
+
+#endif /* CONFIG_FAIR_GROUP_SCHED */
+
static unsigned int get_rr_interval_fair(struct rq *rq, struct task_struct *task)
{
@@ -5048,7 +5536,7 @@ static unsigned int get_rr_interval_fair(struct rq *rq, struct task_struct *task
/*
* All the scheduling class methods:
*/
-static const struct sched_class fair_sched_class = {
+const struct sched_class fair_sched_class = {
.next = &idle_sched_class,
.enqueue_task = enqueue_task_fair,
.dequeue_task = dequeue_task_fair,
@@ -5085,7 +5573,7 @@ static const struct sched_class fair_sched_class = {
};
#ifdef CONFIG_SCHED_DEBUG
-static void print_cfs_stats(struct seq_file *m, int cpu)
+void print_cfs_stats(struct seq_file *m, int cpu)
{
struct cfs_rq *cfs_rq;
@@ -5095,3 +5583,19 @@ static void print_cfs_stats(struct seq_file *m, int cpu)
rcu_read_unlock();
}
#endif
+
+__init void init_sched_fair_class(void)
+{
+#ifdef CONFIG_SMP
+ open_softirq(SCHED_SOFTIRQ, run_rebalance_domains);
+
+#ifdef CONFIG_NO_HZ
+ zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT);
+ alloc_cpumask_var(&nohz.grp_idle_mask, GFP_NOWAIT);
+ atomic_set(&nohz.load_balancer, nr_cpu_ids);
+ atomic_set(&nohz.first_pick_cpu, nr_cpu_ids);
+ atomic_set(&nohz.second_pick_cpu, nr_cpu_ids);
+#endif
+#endif /* SMP */
+
+}