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-rw-r--r--kernel/sched.c1232
1 files changed, 832 insertions, 400 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 1b59e265273..e27a53685ed 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -64,7 +64,6 @@
#include <linux/tsacct_kern.h>
#include <linux/kprobes.h>
#include <linux/delayacct.h>
-#include <linux/reciprocal_div.h>
#include <linux/unistd.h>
#include <linux/pagemap.h>
#include <linux/hrtimer.h>
@@ -120,30 +119,8 @@
*/
#define RUNTIME_INF ((u64)~0ULL)
-#ifdef CONFIG_SMP
-
static void double_rq_lock(struct rq *rq1, struct rq *rq2);
-/*
- * Divide a load by a sched group cpu_power : (load / sg->__cpu_power)
- * Since cpu_power is a 'constant', we can use a reciprocal divide.
- */
-static inline u32 sg_div_cpu_power(const struct sched_group *sg, u32 load)
-{
- return reciprocal_divide(load, sg->reciprocal_cpu_power);
-}
-
-/*
- * Each time a sched group cpu_power is changed,
- * we must compute its reciprocal value
- */
-static inline void sg_inc_cpu_power(struct sched_group *sg, u32 val)
-{
- sg->__cpu_power += val;
- sg->reciprocal_cpu_power = reciprocal_value(sg->__cpu_power);
-}
-#endif
-
static inline int rt_policy(int policy)
{
if (unlikely(policy == SCHED_FIFO || policy == SCHED_RR))
@@ -309,8 +286,8 @@ void set_tg_uid(struct user_struct *user)
/*
* Root task group.
- * Every UID task group (including init_task_group aka UID-0) will
- * be a child to this group.
+ * Every UID task group (including init_task_group aka UID-0) will
+ * be a child to this group.
*/
struct task_group root_task_group;
@@ -318,7 +295,7 @@ struct task_group root_task_group;
/* Default task group's sched entity on each cpu */
static DEFINE_PER_CPU(struct sched_entity, init_sched_entity);
/* Default task group's cfs_rq on each cpu */
-static DEFINE_PER_CPU(struct cfs_rq, init_cfs_rq) ____cacheline_aligned_in_smp;
+static DEFINE_PER_CPU(struct cfs_rq, init_tg_cfs_rq) ____cacheline_aligned_in_smp;
#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_RT_GROUP_SCHED
@@ -616,6 +593,7 @@ struct rq {
unsigned char idle_at_tick;
/* For active balancing */
+ int post_schedule;
int active_balance;
int push_cpu;
/* cpu of this runqueue: */
@@ -626,6 +604,9 @@ struct rq {
struct task_struct *migration_thread;
struct list_head migration_queue;
+
+ u64 rt_avg;
+ u64 age_stamp;
#endif
/* calc_load related fields */
@@ -693,6 +674,7 @@ static inline int cpu_of(struct rq *rq)
#define this_rq() (&__get_cpu_var(runqueues))
#define task_rq(p) cpu_rq(task_cpu(p))
#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
+#define raw_rq() (&__raw_get_cpu_var(runqueues))
inline void update_rq_clock(struct rq *rq)
{
@@ -861,6 +843,14 @@ unsigned int sysctl_sched_shares_ratelimit = 250000;
unsigned int sysctl_sched_shares_thresh = 4;
/*
+ * period over which we average the RT time consumption, measured
+ * in ms.
+ *
+ * default: 1s
+ */
+const_debug unsigned int sysctl_sched_time_avg = MSEC_PER_SEC;
+
+/*
* period over which we measure -rt task cpu usage in us.
* default: 1s
*/
@@ -1278,12 +1268,37 @@ void wake_up_idle_cpu(int cpu)
}
#endif /* CONFIG_NO_HZ */
+static u64 sched_avg_period(void)
+{
+ return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2;
+}
+
+static void sched_avg_update(struct rq *rq)
+{
+ s64 period = sched_avg_period();
+
+ while ((s64)(rq->clock - rq->age_stamp) > period) {
+ rq->age_stamp += period;
+ rq->rt_avg /= 2;
+ }
+}
+
+static void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
+{
+ rq->rt_avg += rt_delta;
+ sched_avg_update(rq);
+}
+
#else /* !CONFIG_SMP */
static void resched_task(struct task_struct *p)
{
assert_spin_locked(&task_rq(p)->lock);
set_tsk_need_resched(p);
}
+
+static void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
+{
+}
#endif /* CONFIG_SMP */
#if BITS_PER_LONG == 32
@@ -1513,28 +1528,35 @@ static unsigned long cpu_avg_load_per_task(int cpu)
#ifdef CONFIG_FAIR_GROUP_SCHED
+struct update_shares_data {
+ unsigned long rq_weight[NR_CPUS];
+};
+
+static DEFINE_PER_CPU(struct update_shares_data, update_shares_data);
+
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, int cpu,
- unsigned long sd_shares, unsigned long sd_rq_weight)
+static void update_group_shares_cpu(struct task_group *tg, int cpu,
+ unsigned long sd_shares,
+ unsigned long sd_rq_weight,
+ struct update_shares_data *usd)
{
- unsigned long shares;
- unsigned long rq_weight;
-
- if (!tg->se[cpu])
- return;
+ unsigned long shares, rq_weight;
+ int boost = 0;
- rq_weight = tg->cfs_rq[cpu]->rq_weight;
+ rq_weight = usd->rq_weight[cpu];
+ if (!rq_weight) {
+ boost = 1;
+ rq_weight = NICE_0_LOAD;
+ }
/*
- * \Sum shares * rq_weight
- * shares = -----------------------
- * \Sum rq_weight
- *
+ * \Sum_j shares_j * rq_weight_i
+ * shares_i = -----------------------------
+ * \Sum_j rq_weight_j
*/
shares = (sd_shares * rq_weight) / sd_rq_weight;
shares = clamp_t(unsigned long, shares, MIN_SHARES, MAX_SHARES);
@@ -1545,8 +1567,8 @@ update_group_shares_cpu(struct task_group *tg, int cpu,
unsigned long flags;
spin_lock_irqsave(&rq->lock, flags);
- tg->cfs_rq[cpu]->shares = shares;
-
+ tg->cfs_rq[cpu]->rq_weight = boost ? 0 : rq_weight;
+ tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
__set_se_shares(tg->se[cpu], shares);
spin_unlock_irqrestore(&rq->lock, flags);
}
@@ -1559,22 +1581,30 @@ update_group_shares_cpu(struct task_group *tg, int cpu,
*/
static int tg_shares_up(struct task_group *tg, void *data)
{
- unsigned long weight, rq_weight = 0;
- unsigned long shares = 0;
+ unsigned long weight, rq_weight = 0, shares = 0;
+ struct update_shares_data *usd;
struct sched_domain *sd = data;
+ unsigned long flags;
int i;
+ if (!tg->se[0])
+ return 0;
+
+ local_irq_save(flags);
+ usd = &__get_cpu_var(update_shares_data);
+
for_each_cpu(i, sched_domain_span(sd)) {
+ weight = tg->cfs_rq[i]->load.weight;
+ usd->rq_weight[i] = 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.
*/
- weight = tg->cfs_rq[i]->load.weight;
if (!weight)
weight = NICE_0_LOAD;
- tg->cfs_rq[i]->rq_weight = weight;
rq_weight += weight;
shares += tg->cfs_rq[i]->shares;
}
@@ -1586,7 +1616,9 @@ static int tg_shares_up(struct task_group *tg, void *data)
shares = tg->shares;
for_each_cpu(i, sched_domain_span(sd))
- update_group_shares_cpu(tg, i, shares, rq_weight);
+ update_group_shares_cpu(tg, i, shares, rq_weight, usd);
+
+ local_irq_restore(flags);
return 0;
}
@@ -1616,8 +1648,14 @@ static int tg_load_down(struct task_group *tg, void *data)
static void update_shares(struct sched_domain *sd)
{
- u64 now = cpu_clock(raw_smp_processor_id());
- s64 elapsed = now - sd->last_update;
+ s64 elapsed;
+ u64 now;
+
+ if (root_task_group_empty())
+ return;
+
+ now = cpu_clock(raw_smp_processor_id());
+ elapsed = now - sd->last_update;
if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) {
sd->last_update = now;
@@ -1627,6 +1665,9 @@ static void update_shares(struct sched_domain *sd)
static void update_shares_locked(struct rq *rq, struct sched_domain *sd)
{
+ if (root_task_group_empty())
+ return;
+
spin_unlock(&rq->lock);
update_shares(sd);
spin_lock(&rq->lock);
@@ -1634,6 +1675,9 @@ static void update_shares_locked(struct rq *rq, struct sched_domain *sd)
static void update_h_load(long cpu)
{
+ if (root_task_group_empty())
+ return;
+
walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
}
@@ -2268,8 +2312,7 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p, int this_cpu)
}
/* Adjust by relative CPU power of the group */
- avg_load = sg_div_cpu_power(group,
- avg_load * SCHED_LOAD_SCALE);
+ avg_load = (avg_load * SCHED_LOAD_SCALE) / group->cpu_power;
if (local_group) {
this_load = avg_load;
@@ -2637,9 +2680,32 @@ void sched_fork(struct task_struct *p, int clone_flags)
set_task_cpu(p, cpu);
/*
- * Make sure we do not leak PI boosting priority to the child:
+ * Make sure we do not leak PI boosting priority to the child.
*/
p->prio = current->normal_prio;
+
+ /*
+ * Revert to default priority/policy on fork if requested.
+ */
+ if (unlikely(p->sched_reset_on_fork)) {
+ if (p->policy == SCHED_FIFO || p->policy == SCHED_RR)
+ p->policy = SCHED_NORMAL;
+
+ if (p->normal_prio < DEFAULT_PRIO)
+ p->prio = DEFAULT_PRIO;
+
+ if (PRIO_TO_NICE(p->static_prio) < 0) {
+ p->static_prio = NICE_TO_PRIO(0);
+ set_load_weight(p);
+ }
+
+ /*
+ * We don't need the reset flag anymore after the fork. It has
+ * fulfilled its duty:
+ */
+ p->sched_reset_on_fork = 0;
+ }
+
if (!rt_prio(p->prio))
p->sched_class = &fair_sched_class;
@@ -2796,12 +2862,6 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
{
struct mm_struct *mm = rq->prev_mm;
long prev_state;
-#ifdef CONFIG_SMP
- int post_schedule = 0;
-
- if (current->sched_class->needs_post_schedule)
- post_schedule = current->sched_class->needs_post_schedule(rq);
-#endif
rq->prev_mm = NULL;
@@ -2820,10 +2880,6 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
finish_arch_switch(prev);
perf_counter_task_sched_in(current, cpu_of(rq));
finish_lock_switch(rq, prev);
-#ifdef CONFIG_SMP
- if (post_schedule)
- current->sched_class->post_schedule(rq);
-#endif
fire_sched_in_preempt_notifiers(current);
if (mm)
@@ -2838,6 +2894,42 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
}
}
+#ifdef CONFIG_SMP
+
+/* assumes rq->lock is held */
+static inline void pre_schedule(struct rq *rq, struct task_struct *prev)
+{
+ if (prev->sched_class->pre_schedule)
+ prev->sched_class->pre_schedule(rq, prev);
+}
+
+/* rq->lock is NOT held, but preemption is disabled */
+static inline void post_schedule(struct rq *rq)
+{
+ if (rq->post_schedule) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&rq->lock, flags);
+ if (rq->curr->sched_class->post_schedule)
+ rq->curr->sched_class->post_schedule(rq);
+ spin_unlock_irqrestore(&rq->lock, flags);
+
+ rq->post_schedule = 0;
+ }
+}
+
+#else
+
+static inline void pre_schedule(struct rq *rq, struct task_struct *p)
+{
+}
+
+static inline void post_schedule(struct rq *rq)
+{
+}
+
+#endif
+
/**
* schedule_tail - first thing a freshly forked thread must call.
* @prev: the thread we just switched away from.
@@ -2848,6 +2940,13 @@ asmlinkage void schedule_tail(struct task_struct *prev)
struct rq *rq = this_rq();
finish_task_switch(rq, prev);
+
+ /*
+ * FIXME: do we need to worry about rq being invalidated by the
+ * task_switch?
+ */
+ post_schedule(rq);
+
#ifdef __ARCH_WANT_UNLOCKED_CTXSW
/* In this case, finish_task_switch does not reenable preemption */
preempt_enable();
@@ -3379,9 +3478,10 @@ static int move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
{
const struct sched_class *class;
- for (class = sched_class_highest; class; class = class->next)
+ for_each_class(class) {
if (class->move_one_task(this_rq, this_cpu, busiest, sd, idle))
return 1;
+ }
return 0;
}
@@ -3544,7 +3644,7 @@ static inline void update_sd_power_savings_stats(struct sched_group *group,
* capacity but still has some space to pick up some load
* from other group and save more power
*/
- if (sgs->sum_nr_running > sgs->group_capacity - 1)
+ if (sgs->sum_nr_running + 1 > sgs->group_capacity)
return;
if (sgs->sum_nr_running > sds->leader_nr_running ||
@@ -3611,6 +3711,77 @@ static inline int check_power_save_busiest_group(struct sd_lb_stats *sds,
}
#endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
+unsigned long __weak arch_scale_smt_power(struct sched_domain *sd, int cpu)
+{
+ unsigned long weight = cpumask_weight(sched_domain_span(sd));
+ unsigned long smt_gain = sd->smt_gain;
+
+ smt_gain /= weight;
+
+ return smt_gain;
+}
+
+unsigned long scale_rt_power(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ u64 total, available;
+
+ sched_avg_update(rq);
+
+ total = sched_avg_period() + (rq->clock - rq->age_stamp);
+ available = total - rq->rt_avg;
+
+ if (unlikely((s64)total < SCHED_LOAD_SCALE))
+ total = SCHED_LOAD_SCALE;
+
+ total >>= SCHED_LOAD_SHIFT;
+
+ return div_u64(available, total);
+}
+
+static void update_cpu_power(struct sched_domain *sd, int cpu)
+{
+ unsigned long weight = cpumask_weight(sched_domain_span(sd));
+ unsigned long power = SCHED_LOAD_SCALE;
+ struct sched_group *sdg = sd->groups;
+
+ /* here we could scale based on cpufreq */
+
+ if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
+ power *= arch_scale_smt_power(sd, cpu);
+ power >>= SCHED_LOAD_SHIFT;
+ }
+
+ power *= scale_rt_power(cpu);
+ power >>= SCHED_LOAD_SHIFT;
+
+ if (!power)
+ power = 1;
+
+ sdg->cpu_power = power;
+}
+
+static void update_group_power(struct sched_domain *sd, int cpu)
+{
+ struct sched_domain *child = sd->child;
+ struct sched_group *group, *sdg = sd->groups;
+ unsigned long power;
+
+ if (!child) {
+ update_cpu_power(sd, cpu);
+ return;
+ }
+
+ power = 0;
+
+ group = child->groups;
+ do {
+ power += group->cpu_power;
+ group = group->next;
+ } while (group != child->groups);
+
+ sdg->cpu_power = power;
+}
/**
* update_sg_lb_stats - Update sched_group's statistics for load balancing.
@@ -3624,7 +3795,8 @@ static inline int check_power_save_busiest_group(struct sd_lb_stats *sds,
* @balance: Should we balance.
* @sgs: variable to hold the statistics for this group.
*/
-static inline void update_sg_lb_stats(struct sched_group *group, int this_cpu,
+static inline void update_sg_lb_stats(struct sched_domain *sd,
+ struct sched_group *group, int this_cpu,
enum cpu_idle_type idle, int load_idx, int *sd_idle,
int local_group, const struct cpumask *cpus,
int *balance, struct sg_lb_stats *sgs)
@@ -3635,8 +3807,11 @@ static inline void update_sg_lb_stats(struct sched_group *group, int this_cpu,
unsigned long sum_avg_load_per_task;
unsigned long avg_load_per_task;
- if (local_group)
+ if (local_group) {
balance_cpu = group_first_cpu(group);
+ if (balance_cpu == this_cpu)
+ update_group_power(sd, this_cpu);
+ }
/* Tally up the load of all CPUs in the group */
sum_avg_load_per_task = avg_load_per_task = 0;
@@ -3685,8 +3860,7 @@ static inline void update_sg_lb_stats(struct sched_group *group, int this_cpu,
}
/* Adjust by relative CPU power of the group */
- sgs->avg_load = sg_div_cpu_power(group,
- sgs->group_load * SCHED_LOAD_SCALE);
+ sgs->avg_load = (sgs->group_load * SCHED_LOAD_SCALE) / group->cpu_power;
/*
@@ -3698,14 +3872,14 @@ static inline void update_sg_lb_stats(struct sched_group *group, int this_cpu,
* normalized nr_running number somewhere that negates
* the hierarchy?
*/
- avg_load_per_task = sg_div_cpu_power(group,
- sum_avg_load_per_task * SCHED_LOAD_SCALE);
+ avg_load_per_task = (sum_avg_load_per_task * SCHED_LOAD_SCALE) /
+ group->cpu_power;
if ((max_cpu_load - min_cpu_load) > 2*avg_load_per_task)
sgs->group_imb = 1;
- sgs->group_capacity = group->__cpu_power / SCHED_LOAD_SCALE;
-
+ sgs->group_capacity =
+ DIV_ROUND_CLOSEST(group->cpu_power, SCHED_LOAD_SCALE);
}
/**
@@ -3723,9 +3897,13 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
const struct cpumask *cpus, int *balance,
struct sd_lb_stats *sds)
{
+ struct sched_domain *child = sd->child;
struct sched_group *group = sd->groups;
struct sg_lb_stats sgs;
- int load_idx;
+ int load_idx, prefer_sibling = 0;
+
+ if (child && child->flags & SD_PREFER_SIBLING)
+ prefer_sibling = 1;
init_sd_power_savings_stats(sd, sds, idle);
load_idx = get_sd_load_idx(sd, idle);
@@ -3736,14 +3914,22 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
local_group = cpumask_test_cpu(this_cpu,
sched_group_cpus(group));
memset(&sgs, 0, sizeof(sgs));
- update_sg_lb_stats(group, this_cpu, idle, load_idx, sd_idle,
+ update_sg_lb_stats(sd, group, this_cpu, idle, load_idx, sd_idle,
local_group, cpus, balance, &sgs);
if (local_group && balance && !(*balance))
return;
sds->total_load += sgs.group_load;
- sds->total_pwr += group->__cpu_power;
+ sds->total_pwr += group->cpu_power;
+
+ /*
+ * In case the child domain prefers tasks go to siblings
+ * first, lower the group capacity to one so that we'll try
+ * and move all the excess tasks away.
+ */
+ if (prefer_sibling)
+ sgs.group_capacity = min(sgs.group_capacity, 1UL);
if (local_group) {
sds->this_load = sgs.avg_load;
@@ -3763,7 +3949,6 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
update_sd_power_savings_stats(group, sds, local_group, &sgs);
group = group->next;
} while (group != sd->groups);
-
}
/**
@@ -3801,28 +3986,28 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,
* moving them.
*/
- pwr_now += sds->busiest->__cpu_power *
+ pwr_now += sds->busiest->cpu_power *
min(sds->busiest_load_per_task, sds->max_load);
- pwr_now += sds->this->__cpu_power *
+ pwr_now += sds->this->cpu_power *
min(sds->this_load_per_task, sds->this_load);
pwr_now /= SCHED_LOAD_SCALE;
/* Amount of load we'd subtract */
- tmp = sg_div_cpu_power(sds->busiest,
- sds->busiest_load_per_task * SCHED_LOAD_SCALE);
+ tmp = (sds->busiest_load_per_task * SCHED_LOAD_SCALE) /
+ sds->busiest->cpu_power;
if (sds->max_load > tmp)
- pwr_move += sds->busiest->__cpu_power *
+ pwr_move += sds->busiest->cpu_power *
min(sds->busiest_load_per_task, sds->max_load - tmp);
/* Amount of load we'd add */
- if (sds->max_load * sds->busiest->__cpu_power <
+ if (sds->max_load * sds->busiest->cpu_power <
sds->busiest_load_per_task * SCHED_LOAD_SCALE)
- tmp = sg_div_cpu_power(sds->this,
- sds->max_load * sds->busiest->__cpu_power);
+ tmp = (sds->max_load * sds->busiest->cpu_power) /
+ sds->this->cpu_power;
else
- tmp = sg_div_cpu_power(sds->this,
- sds->busiest_load_per_task * SCHED_LOAD_SCALE);
- pwr_move += sds->this->__cpu_power *
+ tmp = (sds->busiest_load_per_task * SCHED_LOAD_SCALE) /
+ sds->this->cpu_power;
+ pwr_move += sds->this->cpu_power *
min(sds->this_load_per_task, sds->this_load + tmp);
pwr_move /= SCHED_LOAD_SCALE;
@@ -3857,8 +4042,8 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,
sds->max_load - sds->busiest_load_per_task);
/* How much load to actually move to equalise the imbalance */
- *imbalance = min(max_pull * sds->busiest->__cpu_power,
- (sds->avg_load - sds->this_load) * sds->this->__cpu_power)
+ *imbalance = min(max_pull * sds->busiest->cpu_power,
+ (sds->avg_load - sds->this_load) * sds->this->cpu_power)
/ SCHED_LOAD_SCALE;
/*
@@ -3976,6 +4161,26 @@ ret:
return NULL;
}
+static struct sched_group *group_of(int cpu)
+{
+ struct sched_domain *sd = rcu_dereference(cpu_rq(cpu)->sd);
+
+ if (!sd)
+ return NULL;
+
+ return sd->groups;
+}
+
+static unsigned long power_of(int cpu)
+{
+ struct sched_group *group = group_of(cpu);
+
+ if (!group)
+ return SCHED_LOAD_SCALE;
+
+ return group->cpu_power;
+}
+
/*
* find_busiest_queue - find the busiest runqueue among the cpus in group.
*/
@@ -3988,15 +4193,18 @@ find_busiest_queue(struct sched_group *group, enum cpu_idle_type idle,
int i;
for_each_cpu(i, sched_group_cpus(group)) {
+ unsigned long power = power_of(i);
+ unsigned long capacity = DIV_ROUND_CLOSEST(power, SCHED_LOAD_SCALE);
unsigned long wl;
if (!cpumask_test_cpu(i, cpus))
continue;
rq = cpu_rq(i);
- wl = weighted_cpuload(i);
+ wl = weighted_cpuload(i) * SCHED_LOAD_SCALE;
+ wl /= power;
- if (rq->nr_running == 1 && wl > imbalance)
+ if (capacity && rq->nr_running == 1 && wl > imbalance)
continue;
if (wl > max_load) {
@@ -5325,7 +5533,7 @@ need_resched:
preempt_disable();
cpu = smp_processor_id();
rq = cpu_rq(cpu);
- rcu_qsctr_inc(cpu);
+ rcu_sched_qs(cpu);
prev = rq->curr;
switch_count = &prev->nivcsw;
@@ -5349,10 +5557,7 @@ need_resched_nonpreemptible:
switch_count = &prev->nvcsw;
}
-#ifdef CONFIG_SMP
- if (prev->sched_class->pre_schedule)
- prev->sched_class->pre_schedule(rq, prev);
-#endif
+ pre_schedule(rq, prev);
if (unlikely(!rq->nr_running))
idle_balance(cpu, rq);
@@ -5378,6 +5583,8 @@ need_resched_nonpreemptible:
} else
spin_unlock_irq(&rq->lock);
+ post_schedule(rq);
+
if (unlikely(reacquire_kernel_lock(current) < 0))
goto need_resched_nonpreemptible;
@@ -6123,17 +6330,25 @@ static int __sched_setscheduler(struct task_struct *p, int policy,
unsigned long flags;
const struct sched_class *prev_class = p->sched_class;
struct rq *rq;
+ int reset_on_fork;
/* may grab non-irq protected spin_locks */
BUG_ON(in_interrupt());
recheck:
/* double check policy once rq lock held */
- if (policy < 0)
+ if (policy < 0) {
+ reset_on_fork = p->sched_reset_on_fork;
policy = oldpolicy = p->policy;
- else if (policy != SCHED_FIFO && policy != SCHED_RR &&
- policy != SCHED_NORMAL && policy != SCHED_BATCH &&
- policy != SCHED_IDLE)
- return -EINVAL;
+ } else {
+ reset_on_fork = !!(policy & SCHED_RESET_ON_FORK);
+ policy &= ~SCHED_RESET_ON_FORK;
+
+ if (policy != SCHED_FIFO && policy != SCHED_RR &&
+ policy != SCHED_NORMAL && policy != SCHED_BATCH &&
+ policy != SCHED_IDLE)
+ return -EINVAL;
+ }
+
/*
* Valid priorities for SCHED_FIFO and SCHED_RR are
* 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL,
@@ -6177,6 +6392,10 @@ recheck:
/* can't change other user's priorities */
if (!check_same_owner(p))
return -EPERM;
+
+ /* Normal users shall not reset the sched_reset_on_fork flag */
+ if (p->sched_reset_on_fork && !reset_on_fork)
+ return -EPERM;
}
if (user) {
@@ -6220,6 +6439,8 @@ recheck:
if (running)
p->sched_class->put_prev_task(rq, p);
+ p->sched_reset_on_fork = reset_on_fork;
+
oldprio = p->prio;
__setscheduler(rq, p, policy, param->sched_priority);
@@ -6336,14 +6557,15 @@ SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
if (p) {
retval = security_task_getscheduler(p);
if (!retval)
- retval = p->policy;
+ retval = p->policy
+ | (p->sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0);
}
read_unlock(&tasklist_lock);
return retval;
}
/**
- * sys_sched_getscheduler - get the RT priority of a thread
+ * sys_sched_getparam - get the RT priority of a thread
* @pid: the pid in question.
* @param: structure containing the RT priority.
*/
@@ -6571,19 +6793,9 @@ static inline int should_resched(void)
static void __cond_resched(void)
{
-#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
- __might_sleep(__FILE__, __LINE__);
-#endif
- /*
- * The BKS might be reacquired before we have dropped
- * PREEMPT_ACTIVE, which could trigger a second
- * cond_resched() call.
- */
- do {
- add_preempt_count(PREEMPT_ACTIVE);
- schedule();
- sub_preempt_count(PREEMPT_ACTIVE);
- } while (need_resched());
+ add_preempt_count(PREEMPT_ACTIVE);
+ schedule();
+ sub_preempt_count(PREEMPT_ACTIVE);
}
int __sched _cond_resched(void)
@@ -6597,18 +6809,20 @@ int __sched _cond_resched(void)
EXPORT_SYMBOL(_cond_resched);
/*
- * cond_resched_lock() - if a reschedule is pending, drop the given lock,
+ * __cond_resched_lock() - if a reschedule is pending, drop the given lock,
* call schedule, and on return reacquire the lock.
*
* This works OK both with and without CONFIG_PREEMPT. We do strange low-level
* operations here to prevent schedule() from being called twice (once via
* spin_unlock(), once by hand).
*/
-int cond_resched_lock(spinlock_t *lock)
+int __cond_resched_lock(spinlock_t *lock)
{
int resched = should_resched();
int ret = 0;
+ lockdep_assert_held(lock);
+
if (spin_needbreak(lock) || resched) {
spin_unlock(lock);
if (resched)
@@ -6620,9 +6834,9 @@ int cond_resched_lock(spinlock_t *lock)
}
return ret;
}
-EXPORT_SYMBOL(cond_resched_lock);
+EXPORT_SYMBOL(__cond_resched_lock);
-int __sched cond_resched_softirq(void)
+int __sched __cond_resched_softirq(void)
{
BUG_ON(!in_softirq());
@@ -6634,7 +6848,7 @@ int __sched cond_resched_softirq(void)
}
return 0;
}
-EXPORT_SYMBOL(cond_resched_softirq);
+EXPORT_SYMBOL(__cond_resched_softirq);
/**
* yield - yield the current processor to other threads.
@@ -6658,11 +6872,13 @@ EXPORT_SYMBOL(yield);
*/
void __sched io_schedule(void)
{
- struct rq *rq = &__raw_get_cpu_var(runqueues);
+ struct rq *rq = raw_rq();
delayacct_blkio_start();
atomic_inc(&rq->nr_iowait);
+ current->in_iowait = 1;
schedule();
+ current->in_iowait = 0;
atomic_dec(&rq->nr_iowait);
delayacct_blkio_end();
}
@@ -6670,12 +6886,14 @@ EXPORT_SYMBOL(io_schedule);
long __sched io_schedule_timeout(long timeout)
{
- struct rq *rq = &__raw_get_cpu_var(runqueues);
+ struct rq *rq = raw_rq();
long ret;
delayacct_blkio_start();
atomic_inc(&rq->nr_iowait);
+ current->in_iowait = 1;
ret = schedule_timeout(timeout);
+ current->in_iowait = 0;
atomic_dec(&rq->nr_iowait);
delayacct_blkio_end();
return ret;
@@ -6992,8 +7210,12 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
if (migrate_task(p, cpumask_any_and(cpu_online_mask, new_mask), &req)) {
/* Need help from migration thread: drop lock and wait. */
+ struct task_struct *mt = rq->migration_thread;
+
+ get_task_struct(mt);
task_rq_unlock(rq, &flags);
wake_up_process(rq->migration_thread);
+ put_task_struct(mt);
wait_for_completion(&req.done);
tlb_migrate_finish(p->mm);
return 0;
@@ -7051,6 +7273,11 @@ fail:
return ret;
}
+#define RCU_MIGRATION_IDLE 0
+#define RCU_MIGRATION_NEED_QS 1
+#define RCU_MIGRATION_GOT_QS 2
+#define RCU_MIGRATION_MUST_SYNC 3
+
/*
* migration_thread - this is a highprio system thread that performs
* thread migration by bumping thread off CPU then 'pushing' onto
@@ -7058,6 +7285,7 @@ fail:
*/
static int migration_thread(void *data)
{
+ int badcpu;
int cpu = (long)data;
struct rq *rq;
@@ -7092,8 +7320,17 @@ static int migration_thread(void *data)
req = list_entry(head->next, struct migration_req, list);
list_del_init(head->next);
- spin_unlock(&rq->lock);
- __migrate_task(req->task, cpu, req->dest_cpu);
+ if (req->task != NULL) {
+ spin_unlock(&rq->lock);
+ __migrate_task(req->task, cpu, req->dest_cpu);
+ } else if (likely(cpu == (badcpu = smp_processor_id()))) {
+ req->dest_cpu = RCU_MIGRATION_GOT_QS;
+ spin_unlock(&rq->lock);
+ } else {
+ req->dest_cpu = RCU_MIGRATION_MUST_SYNC;
+ spin_unlock(&rq->lock);
+ WARN_ONCE(1, "migration_thread() on CPU %d, expected %d\n", badcpu, cpu);
+ }
local_irq_enable();
complete(&req->done);
@@ -7625,7 +7862,7 @@ static int __init migration_init(void)
migration_call(&migration_notifier, CPU_ONLINE, cpu);
register_cpu_notifier(&migration_notifier);
- return err;
+ return 0;
}
early_initcall(migration_init);
#endif
@@ -7672,7 +7909,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
break;
}
- if (!group->__cpu_power) {
+ if (!group->cpu_power) {
printk(KERN_CONT "\n");
printk(KERN_ERR "ERROR: domain->cpu_power not "
"set\n");
@@ -7696,9 +7933,9 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group));
printk(KERN_CONT " %s", str);
- if (group->__cpu_power != SCHED_LOAD_SCALE) {
- printk(KERN_CONT " (__cpu_power = %d)",
- group->__cpu_power);
+ if (group->cpu_power != SCHED_LOAD_SCALE) {
+ printk(KERN_CONT " (cpu_power = %d)",
+ group->cpu_power);
}
group = group->next;
@@ -7841,7 +8078,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
rq->rd = rd;
cpumask_set_cpu(rq->cpu, rd->span);
- if (cpumask_test_cpu(rq->cpu, cpu_online_mask))
+ if (cpumask_test_cpu(rq->cpu, cpu_active_mask))
set_rq_online(rq);
spin_unlock_irqrestore(&rq->lock, flags);
@@ -7983,7 +8220,7 @@ init_sched_build_groups(const struct cpumask *span,
continue;
cpumask_clear(sched_group_cpus(sg));
- sg->__cpu_power = 0;
+ sg->cpu_power = 0;
for_each_cpu(j, span) {
if (group_fn(j, cpu_map, NULL, tmpmask) != group)
@@ -8091,6 +8328,39 @@ struct static_sched_domain {
DECLARE_BITMAP(span, CONFIG_NR_CPUS);
};
+struct s_data {
+#ifdef CONFIG_NUMA
+ int sd_allnodes;
+ cpumask_var_t domainspan;
+ cpumask_var_t covered;
+ cpumask_var_t notcovered;
+#endif
+ cpumask_var_t nodemask;
+ cpumask_var_t this_sibling_map;
+ cpumask_var_t this_core_map;
+ cpumask_var_t send_covered;
+ cpumask_var_t tmpmask;
+ struct sched_group **sched_group_nodes;
+ struct root_domain *rd;
+};
+
+enum s_alloc {
+ sa_sched_groups = 0,
+ sa_rootdomain,
+ sa_tmpmask,
+ sa_send_covered,
+ sa_this_core_map,
+ sa_this_sibling_map,
+ sa_nodemask,
+ sa_sched_group_nodes,
+#ifdef CONFIG_NUMA
+ sa_notcovered,
+ sa_covered,
+ sa_domainspan,
+#endif
+ sa_none,
+};
+
/*
* SMT sched-domains:
*/
@@ -8208,11 +8478,76 @@ static void init_numa_sched_groups_power(struct sched_group *group_head)
continue;
}
- sg_inc_cpu_power(sg, sd->groups->__cpu_power);
+ sg->cpu_power += sd->groups->cpu_power;
}
sg = sg->next;
} while (sg != group_head);
}
+
+static int build_numa_sched_groups(struct s_data *d,
+ const struct cpumask *cpu_map, int num)
+{
+ struct sched_domain *sd;
+ struct sched_group *sg, *prev;
+ int n, j;
+
+ cpumask_clear(d->covered);
+ cpumask_and(d->nodemask, cpumask_of_node(num), cpu_map);
+ if (cpumask_empty(d->nodemask)) {
+ d->sched_group_nodes[num] = NULL;
+ goto out;
+ }
+
+ sched_domain_node_span(num, d->domainspan);
+ cpumask_and(d->domainspan, d->domainspan, cpu_map);
+
+ sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
+ GFP_KERNEL, num);
+ if (!sg) {
+ printk(KERN_WARNING "Can not alloc domain group for node %d\n",
+ num);
+ return -ENOMEM;
+ }
+ d->sched_group_nodes[num] = sg;
+
+ for_each_cpu(j, d->nodemask) {
+ sd = &per_cpu(node_domains, j).sd;
+ sd->groups = sg;
+ }
+
+ sg->cpu_power = 0;
+ cpumask_copy(sched_group_cpus(sg), d->nodemask);
+ sg->next = sg;
+ cpumask_or(d->covered, d->covered, d->nodemask);
+
+ prev = sg;
+ for (j = 0; j < nr_node_ids; j++) {
+ n = (num + j) % nr_node_ids;
+ cpumask_complement(d->notcovered, d->covered);
+ cpumask_and(d->tmpmask, d->notcovered, cpu_map);
+ cpumask_and(d->tmpmask, d->tmpmask, d->domainspan);
+ if (cpumask_empty(d->tmpmask))
+ break;
+ cpumask_and(d->tmpmask, d->tmpmask, cpumask_of_node(n));
+ if (cpumask_empty(d->tmpmask))
+ continue;
+ sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
+ GFP_KERNEL, num);
+ if (!sg) {
+ printk(KERN_WARNING
+ "Can not alloc domain group for node %d\n", j);
+ return -ENOMEM;
+ }
+ sg->cpu_power = 0;
+ cpumask_copy(sched_group_cpus(sg), d->tmpmask);
+ sg->next = prev->next;
+ cpumask_or(d->covered, d->covered, d->tmpmask);
+ prev->next = sg;
+ prev = sg;
+ }
+out:
+ return 0;
+}
#endif /* CONFIG_NUMA */
#ifdef CONFIG_NUMA
@@ -8266,15 +8601,13 @@ static void free_sched_groups(const struct cpumask *cpu_map,
* there are asymmetries in the topology. If there are asymmetries, group
* having more cpu_power will pickup more load compared to the group having
* less cpu_power.
- *
- * cpu_power will be a multiple of SCHED_LOAD_SCALE. This multiple represents
- * the maximum number of tasks a group can handle in the presence of other idle
- * or lightly loaded groups in the same sched domain.
*/
static void init_sched_groups_power(int cpu, struct sched_domain *sd)
{
struct sched_domain *child;
struct sched_group *group;
+ long power;
+ int weight;
WARN_ON(!sd || !sd->groups);
@@ -8283,28 +8616,32 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
child = sd->child;
- sd->groups->__cpu_power = 0;
+ sd->groups->cpu_power = 0;
- /*
- * For perf policy, if the groups in child domain share resources
- * (for example cores sharing some portions of the cache hierarchy
- * or SMT), then set this domain groups cpu_power such that each group
- * can handle only one task, when there are other idle groups in the
- * same sched domain.
- */
- if (!child || (!(sd->flags & SD_POWERSAVINGS_BALANCE) &&
- (child->flags &
- (SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES)))) {
- sg_inc_cpu_power(sd->groups, SCHED_LOAD_SCALE);
+ if (!child) {
+ power = SCHED_LOAD_SCALE;
+ weight = cpumask_weight(sched_domain_span(sd));
+ /*
+ * SMT siblings share the power of a single core.
+ * Usually multiple threads get a better yield out of
+ * that one core than a single thread would have,
+ * reflect that in sd->smt_gain.
+ */
+ if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
+ power *= sd->smt_gain;
+ power /= weight;
+ power >>= SCHED_LOAD_SHIFT;
+ }
+ sd->groups->cpu_power += power;
return;
}
/*
- * add cpu_power of each child group to this groups cpu_power
+ * Add cpu_power of each child group to this groups cpu_power.
*/
group = child->groups;
do {
- sg_inc_cpu_power(sd->groups, group->__cpu_power);
+ sd->groups->cpu_power += group->cpu_power;
group = group->next;
} while (group != child->groups);
}
@@ -8378,280 +8715,285 @@ static void set_domain_attribute(struct sched_domain *sd,
}
}
-/*
- * Build sched domains for a given set of cpus and attach the sched domains
- * to the individual cpus
- */
-static int __build_sched_domains(const struct cpumask *cpu_map,
- struct sched_domain_attr *attr)
-{
- int i, err = -ENOMEM;
- struct root_domain *rd;
- cpumask_var_t nodemask, this_sibling_map, this_core_map, send_covered,
- tmpmask;
+static void __free_domain_allocs(struct s_data *d, enum s_alloc what,
+ const struct cpumask *cpu_map)
+{
+ switch (what) {
+ case sa_sched_groups:
+ free_sched_groups(cpu_map, d->tmpmask); /* fall through */
+ d->sched_group_nodes = NULL;
+ case sa_rootdomain:
+ free_rootdomain(d->rd); /* fall through */
+ case sa_tmpmask:
+ free_cpumask_var(d->tmpmask); /* fall through */
+ case sa_send_covered:
+ free_cpumask_var(d->send_covered); /* fall through */
+ case sa_this_core_map:
+ free_cpumask_var(d->this_core_map); /* fall through */
+ case sa_this_sibling_map:
+ free_cpumask_var(d->this_sibling_map); /* fall through */
+ case sa_nodemask:
+ free_cpumask_var(d->nodemask); /* fall through */
+ case sa_sched_group_nodes:
#ifdef CONFIG_NUMA
- cpumask_var_t domainspan, covered, notcovered;
- struct sched_group **sched_group_nodes = NULL;
- int sd_allnodes = 0;
-
- if (!alloc_cpumask_var(&domainspan, GFP_KERNEL))
- goto out;
- if (!alloc_cpumask_var(&covered, GFP_KERNEL))
- goto free_domainspan;
- if (!alloc_cpumask_var(&notcovered, GFP_KERNEL))
- goto free_covered;
-#endif
-
- if (!alloc_cpumask_var(&nodemask, GFP_KERNEL))
- goto free_notcovered;
- if (!alloc_cpumask_var(&this_sibling_map, GFP_KERNEL))
- goto free_nodemask;
- if (!alloc_cpumask_var(&this_core_map, GFP_KERNEL))
- goto free_this_sibling_map;
- if (!alloc_cpumask_var(&send_covered, GFP_KERNEL))
- goto free_this_core_map;
- if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
- goto free_send_covered;
+ kfree(d->sched_group_nodes); /* fall through */
+ case sa_notcovered:
+ free_cpumask_var(d->notcovered); /* fall through */
+ case sa_covered:
+ free_cpumask_var(d->covered); /* fall through */
+ case sa_domainspan:
+ free_cpumask_var(d->domainspan); /* fall through */
+#endif
+ case sa_none:
+ break;
+ }
+}
+static enum s_alloc __visit_domain_allocation_hell(struct s_data *d,
+ const struct cpumask *cpu_map)
+{
#ifdef CONFIG_NUMA
- /*
- * Allocate the per-node list of sched groups
- */
- sched_group_nodes = kcalloc(nr_node_ids, sizeof(struct sched_group *),
- GFP_KERNEL);
- if (!sched_group_nodes) {
+ if (!alloc_cpumask_var(&d->domainspan, GFP_KERNEL))
+ return sa_none;
+ if (!alloc_cpumask_var(&d->covered, GFP_KERNEL))
+ return sa_domainspan;
+ if (!alloc_cpumask_var(&d->notcovered, GFP_KERNEL))
+ return sa_covered;
+ /* Allocate the per-node list of sched groups */
+ d->sched_group_nodes = kcalloc(nr_node_ids,
+ sizeof(struct sched_group *), GFP_KERNEL);
+ if (!d->sched_group_nodes) {
printk(KERN_WARNING "Can not alloc sched group node list\n");
- goto free_tmpmask;
- }
-#endif
-
- rd = alloc_rootdomain();
- if (!rd) {
+ return sa_notcovered;
+ }
+ sched_group_nodes_bycpu[cpumask_first(cpu_map)] = d->sched_group_nodes;
+#endif
+ if (!alloc_cpumask_var(&d->nodemask, GFP_KERNEL))
+ return sa_sched_group_nodes;
+ if (!alloc_cpumask_var(&d->this_sibling_map, GFP_KERNEL))
+ return sa_nodemask;
+ if (!alloc_cpumask_var(&d->this_core_map, GFP_KERNEL))
+ return sa_this_sibling_map;
+ if (!alloc_cpumask_var(&d->send_covered, GFP_KERNEL))
+ return sa_this_core_map;
+ if (!alloc_cpumask_var(&d->tmpmask, GFP_KERNEL))
+ return sa_send_covered;
+ d->rd = alloc_rootdomain();
+ if (!d->rd) {
printk(KERN_WARNING "Cannot alloc root domain\n");
- goto free_sched_groups;
+ return sa_tmpmask;
}
+ return sa_rootdomain;
+}
+static struct sched_domain *__build_numa_sched_domains(struct s_data *d,
+ const struct cpumask *cpu_map, struct sched_domain_attr *attr, int i)
+{
+ struct sched_domain *sd = NULL;
#ifdef CONFIG_NUMA
- sched_group_nodes_bycpu[cpumask_first(cpu_map)] = sched_group_nodes;
-#endif
-
- /*
- * Set up domains for cpus specified by the cpu_map.
- */
- for_each_cpu(i, cpu_map) {
- struct sched_domain *sd = NULL, *p;
-
- cpumask_and(nodemask, cpumask_of_node(cpu_to_node(i)), cpu_map);
-
-#ifdef CONFIG_NUMA
- if (cpumask_weight(cpu_map) >
- SD_NODES_PER_DOMAIN*cpumask_weight(nodemask)) {
- sd = &per_cpu(allnodes_domains, i).sd;
- SD_INIT(sd, ALLNODES);
- set_domain_attribute(sd, attr);
- cpumask_copy(sched_domain_span(sd), cpu_map);
- cpu_to_allnodes_group(i, cpu_map, &sd->groups, tmpmask);
- p = sd;
- sd_allnodes = 1;
- } else
- p = NULL;
+ struct sched_domain *parent;
- sd = &per_cpu(node_domains, i).sd;
- SD_INIT(sd, NODE);
+ d->sd_allnodes = 0;
+ if (cpumask_weight(cpu_map) >
+ SD_NODES_PER_DOMAIN * cpumask_weight(d->nodemask)) {
+ sd = &per_cpu(allnodes_domains, i).sd;
+ SD_INIT(sd, ALLNODES);
set_domain_attribute(sd, attr);
- sched_domain_node_span(cpu_to_node(i), sched_domain_span(sd));
- sd->parent = p;
- if (p)
- p->child = sd;
- cpumask_and(sched_domain_span(sd),
- sched_domain_span(sd), cpu_map);
+ cpumask_copy(sched_domain_span(sd), cpu_map);
+ cpu_to_allnodes_group(i, cpu_map, &sd->groups, d->tmpmask);
+ d->sd_allnodes = 1;
+ }
+ parent = sd;
+
+ sd = &per_cpu(node_domains, i).sd;
+ SD_INIT(sd, NODE);
+ set_domain_attribute(sd, attr);
+ sched_domain_node_span(cpu_to_node(i), sched_domain_span(sd));
+ sd->parent = parent;
+ if (parent)
+ parent->child = sd;
+ cpumask_and(sched_domain_span(sd), sched_domain_span(sd), cpu_map);
#endif
+ return sd;
+}
- p = sd;
- sd = &per_cpu(phys_domains, i).sd;
- SD_INIT(sd, CPU);
- set_domain_attribute(sd, attr);
- cpumask_copy(sched_domain_span(sd), nodemask);
- sd->parent = p;
- if (p)
- p->child = sd;
- cpu_to_phys_group(i, cpu_map, &sd->groups, tmpmask);
+static struct sched_domain *__build_cpu_sched_domain(struct s_data *d,
+ const struct cpumask *cpu_map, struct sched_domain_attr *attr,
+ struct sched_domain *parent, int i)
+{
+ struct sched_domain *sd;
+ sd = &per_cpu(phys_domains, i).sd;
+ SD_INIT(sd, CPU);
+ set_domain_attribute(sd, attr);
+ cpumask_copy(sched_domain_span(sd), d->nodemask);
+ sd->parent = parent;
+ if (parent)
+ parent->child = sd;
+ cpu_to_phys_group(i, cpu_map, &sd->groups, d->tmpmask);
+ return sd;
+}
+static struct sched_domain *__build_mc_sched_domain(struct s_data *d,
+ const struct cpumask *cpu_map, struct sched_domain_attr *attr,
+ struct sched_domain *parent, int i)
+{
+ struct sched_domain *sd = parent;
#ifdef CONFIG_SCHED_MC
- p = sd;
- sd = &per_cpu(core_domains, i).sd;
- SD_INIT(sd, MC);
- set_domain_attribute(sd, attr);
- cpumask_and(sched_domain_span(sd), cpu_map,
- cpu_coregroup_mask(i));
- sd->parent = p;
- p->child = sd;
- cpu_to_core_group(i, cpu_map, &sd->groups, tmpmask);
+ sd = &per_cpu(core_domains, i).sd;
+ SD_INIT(sd, MC);
+ set_domain_attribute(sd, attr);
+ cpumask_and(sched_domain_span(sd), cpu_map, cpu_coregroup_mask(i));
+ sd->parent = parent;
+ parent->child = sd;
+ cpu_to_core_group(i, cpu_map, &sd->groups, d->tmpmask);
#endif
+ return sd;
+}
+static struct sched_domain *__build_smt_sched_domain(struct s_data *d,
+ const struct cpumask *cpu_map, struct sched_domain_attr *attr,
+ struct sched_domain *parent, int i)
+{
+ struct sched_domain *sd = parent;
#ifdef CONFIG_SCHED_SMT
- p = sd;
- sd = &per_cpu(cpu_domains, i).sd;
- SD_INIT(sd, SIBLING);
- set_domain_attribute(sd, attr);
- cpumask_and(sched_domain_span(sd),
- topology_thread_cpumask(i), cpu_map);
- sd->parent = p;
- p->child = sd;
- cpu_to_cpu_group(i, cpu_map, &sd->groups, tmpmask);
+ sd = &per_cpu(cpu_domains, i).sd;
+ SD_INIT(sd, SIBLING);
+ set_domain_attribute(sd, attr);
+ cpumask_and(sched_domain_span(sd), cpu_map, topology_thread_cpumask(i));
+ sd->parent = parent;
+ parent->child = sd;
+ cpu_to_cpu_group(i, cpu_map, &sd->groups, d->tmpmask);
#endif
- }
+ return sd;
+}
+static void build_sched_groups(struct s_data *d, enum sched_domain_level l,
+ const struct cpumask *cpu_map, int cpu)
+{
+ switch (l) {
#ifdef CONFIG_SCHED_SMT
- /* Set up CPU (sibling) groups */
- for_each_cpu(i, cpu_map) {
- cpumask_and(this_sibling_map,
- topology_thread_cpumask(i), cpu_map);
- if (i != cpumask_first(this_sibling_map))
- continue;
-
- init_sched_build_groups(this_sibling_map, cpu_map,
- &cpu_to_cpu_group,
- send_covered, tmpmask);
- }
+ case SD_LV_SIBLING: /* set up CPU (sibling) groups */
+ cpumask_and(d->this_sibling_map, cpu_map,
+ topology_thread_cpumask(cpu));
+ if (cpu == cpumask_first(d->this_sibling_map))
+ init_sched_build_groups(d->this_sibling_map, cpu_map,
+ &cpu_to_cpu_group,
+ d->send_covered, d->tmpmask);
+ break;
#endif
-
#ifdef CONFIG_SCHED_MC
- /* Set up multi-core groups */
- for_each_cpu(i, cpu_map) {
- cpumask_and(this_core_map, cpu_coregroup_mask(i), cpu_map);
- if (i != cpumask_first(this_core_map))
- continue;
-
- init_sched_build_groups(this_core_map, cpu_map,
- &cpu_to_core_group,
- send_covered, tmpmask);
- }
+ case SD_LV_MC: /* set up multi-core groups */
+ cpumask_and(d->this_core_map, cpu_map, cpu_coregroup_mask(cpu));
+ if (cpu == cpumask_first(d->this_core_map))
+ init_sched_build_groups(d->this_core_map, cpu_map,
+ &cpu_to_core_group,
+ d->send_covered, d->tmpmask);
+ break;
#endif
-
- /* Set up physical groups */
- for (i = 0; i < nr_node_ids; i++) {
- cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
- if (cpumask_empty(nodemask))
- continue;
-
- init_sched_build_groups(nodemask, cpu_map,
- &cpu_to_phys_group,
- send_covered, tmpmask);
- }
-
+ case SD_LV_CPU: /* set up physical groups */
+ cpumask_and(d->nodemask, cpumask_of_node(cpu), cpu_map);
+ if (!cpumask_empty(d->nodemask))
+ init_sched_build_groups(d->nodemask, cpu_map,
+ &cpu_to_phys_group,
+ d->send_covered, d->tmpmask);
+ break;
#ifdef CONFIG_NUMA
- /* Set up node groups */
- if (sd_allnodes) {
- init_sched_build_groups(cpu_map, cpu_map,
- &cpu_to_allnodes_group,
- send_covered, tmpmask);
+ case SD_LV_ALLNODES:
+ init_sched_build_groups(cpu_map, cpu_map, &cpu_to_allnodes_group,
+ d->send_covered, d->tmpmask);
+ break;
+#endif
+ default:
+ break;
}
+}
- for (i = 0; i < nr_node_ids; i++) {
- /* Set up node groups */
- struct sched_group *sg, *prev;
- int j;
-
- cpumask_clear(covered);
- cpumask_and(nodemask, cpumask_of_node(i), cpu_map);
- if (cpumask_empty(nodemask)) {
- sched_group_nodes[i] = NULL;
- continue;
- }
+/*
+ * Build sched domains for a given set of cpus and attach the sched domains
+ * to the individual cpus
+ */
+static int __build_sched_domains(const struct cpumask *cpu_map,
+ struct sched_domain_attr *attr)
+{
+ enum s_alloc alloc_state = sa_none;
+ struct s_data d;
+ struct sched_domain *sd;
+ int i;
+#ifdef CONFIG_NUMA
+ d.sd_allnodes = 0;
+#endif
- sched_domain_node_span(i, domainspan);
- cpumask_and(domainspan, domainspan, cpu_map);
+ alloc_state = __visit_domain_allocation_hell(&d, cpu_map);
+ if (alloc_state != sa_rootdomain)
+ goto error;
+ alloc_state = sa_sched_groups;
- sg = kmalloc_node(sizeof(struct sched_group) + cpumask_size(),
- GFP_KERNEL, i);
- if (!sg) {
- printk(KERN_WARNING "Can not alloc domain group for "
- "node %d\n", i);
- goto error;
- }
- sched_group_nodes[i] = sg;
- for_each_cpu(j, nodemask) {
- struct sched_domain *sd;
+ /*
+ * Set up domains for cpus specified by the cpu_map.
+ */
+ for_each_cpu(i, cpu_map) {
+ cpumask_and(d.nodemask, cpumask_of_node(cpu_to_node(i)),
+ cpu_map);
- sd = &per_cpu(node_domains, j).sd;
- sd->groups = sg;
- }
- sg->__cpu_power = 0;
- cpumask_copy(sched_group_cpus(sg), nodemask);
- sg->next = sg;
- cpumask_or(covered, covered, nodemask);
- prev = sg;
+ sd = __build_numa_sched_domains(&d, cpu_map, attr, i);
+ sd = __build_cpu_sched_domain(&d, cpu_map, attr, sd, i);
+ sd = __build_mc_sched_domain(&d, cpu_map, attr, sd, i);
+ sd = __build_smt_sched_domain(&d, cpu_map, attr, sd, i);
+ }
- for (j = 0; j < nr_node_ids; j++) {
- int n = (i + j) % nr_node_ids;
+ for_each_cpu(i, cpu_map) {
+ build_sched_groups(&d, SD_LV_SIBLING, cpu_map, i);
+ build_sched_groups(&d, SD_LV_MC, cpu_map, i);
+ }
- cpumask_complement(notcovered, covered);
- cpumask_and(tmpmask, notcovered, cpu_map);
- cpumask_and(tmpmask, tmpmask, domainspan);
- if (cpumask_empty(tmpmask))
- break;
+ /* Set up physical groups */
+ for (i = 0; i < nr_node_ids; i++)
+ build_sched_groups(&d, SD_LV_CPU, cpu_map, i);
- cpumask_and(tmpmask, tmpmask, cpumask_of_node(n));
- if (cpumask_empty(tmpmask))
- continue;
+#ifdef CONFIG_NUMA
+ /* Set up node groups */
+ if (d.sd_allnodes)
+ build_sched_groups(&d, SD_LV_ALLNODES, cpu_map, 0);
- sg = kmalloc_node(sizeof(struct sched_group) +
- cpumask_size(),
- GFP_KERNEL, i);
- if (!sg) {
- printk(KERN_WARNING
- "Can not alloc domain group for node %d\n", j);
- goto error;
- }
- sg->__cpu_power = 0;
- cpumask_copy(sched_group_cpus(sg), tmpmask);
- sg->next = prev->next;
- cpumask_or(covered, covered, tmpmask);
- prev->next = sg;
- prev = sg;
- }
- }
+ for (i = 0; i < nr_node_ids; i++)
+ if (build_numa_sched_groups(&d, cpu_map, i))
+ goto error;
#endif
/* Calculate CPU power for physical packages and nodes */
#ifdef CONFIG_SCHED_SMT
for_each_cpu(i, cpu_map) {
- struct sched_domain *sd = &per_cpu(cpu_domains, i).sd;
-
+ sd = &per_cpu(cpu_domains, i).sd;
init_sched_groups_power(i, sd);
}
#endif
#ifdef CONFIG_SCHED_MC
for_each_cpu(i, cpu_map) {
- struct sched_domain *sd = &per_cpu(core_domains, i).sd;
-
+ sd = &per_cpu(core_domains, i).sd;
init_sched_groups_power(i, sd);
}
#endif
for_each_cpu(i, cpu_map) {
- struct sched_domain *sd = &per_cpu(phys_domains, i).sd;
-
+ sd = &per_cpu(phys_domains, i).sd;
init_sched_groups_power(i, sd);
}
#ifdef CONFIG_NUMA
for (i = 0; i < nr_node_ids; i++)
- init_numa_sched_groups_power(sched_group_nodes[i]);
+ init_numa_sched_groups_power(d.sched_group_nodes[i]);
- if (sd_allnodes) {
+ if (d.sd_allnodes) {
struct sched_group *sg;
cpu_to_allnodes_group(cpumask_first(cpu_map), cpu_map, &sg,
- tmpmask);
+ d.tmpmask);
init_numa_sched_groups_power(sg);
}
#endif
/* Attach the domains */
for_each_cpu(i, cpu_map) {
- struct sched_domain *sd;
#ifdef CONFIG_SCHED_SMT
sd = &per_cpu(cpu_domains, i).sd;
#elif defined(CONFIG_SCHED_MC)
@@ -8659,44 +9001,16 @@ static int __build_sched_domains(const struct cpumask *cpu_map,
#else
sd = &per_cpu(phys_domains, i).sd;
#endif
- cpu_attach_domain(sd, rd, i);
+ cpu_attach_domain(sd, d.rd, i);
}
- err = 0;
-
-free_tmpmask:
- free_cpumask_var(tmpmask);
-free_send_covered:
- free_cpumask_var(send_covered);
-free_this_core_map:
- free_cpumask_var(this_core_map);
-free_this_sibling_map:
- free_cpumask_var(this_sibling_map);
-free_nodemask:
- free_cpumask_var(nodemask);
-free_notcovered:
-#ifdef CONFIG_NUMA
- free_cpumask_var(notcovered);
-free_covered:
- free_cpumask_var(covered);
-free_domainspan:
- free_cpumask_var(domainspan);
-out:
-#endif
- return err;
-
-free_sched_groups:
-#ifdef CONFIG_NUMA
- kfree(sched_group_nodes);
-#endif
- goto free_tmpmask;
+ d.sched_group_nodes = NULL; /* don't free this we still need it */
+ __free_domain_allocs(&d, sa_tmpmask, cpu_map);
+ return 0;
-#ifdef CONFIG_NUMA
error:
- free_sched_groups(cpu_map, tmpmask);
- free_rootdomain(rd);
- goto free_tmpmask;
-#endif
+ __free_domain_allocs(&d, alloc_state, cpu_map);
+ return -ENOMEM;
}
static int build_sched_domains(const struct cpumask *cpu_map)
@@ -9304,11 +9618,11 @@ void __init sched_init(void)
* system cpu resource, based on the weight assigned to root
* user's cpu share (INIT_TASK_GROUP_LOAD). This is accomplished
* by letting tasks of init_task_group sit in a separate cfs_rq
- * (init_cfs_rq) and having one entity represent this group of
+ * (init_tg_cfs_rq) and having one entity represent this group of
* tasks in rq->cfs (i.e init_task_group->se[] != NULL).
*/
init_tg_cfs_entry(&init_task_group,
- &per_cpu(init_cfs_rq, i),
+ &per_cpu(init_tg_cfs_rq, i),
&per_cpu(init_sched_entity, i), i, 1,
root_task_group.se[i]);
@@ -9334,6 +9648,7 @@ void __init sched_init(void)
#ifdef CONFIG_SMP
rq->sd = NULL;
rq->rd = NULL;
+ rq->post_schedule = 0;
rq->active_balance = 0;
rq->next_balance = jiffies;
rq->push_cpu = 0;
@@ -9398,13 +9713,20 @@ void __init sched_init(void)
}
#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
-void __might_sleep(char *file, int line)
+static inline int preempt_count_equals(int preempt_offset)
+{
+ int nested = preempt_count() & ~PREEMPT_ACTIVE;
+
+ return (nested == PREEMPT_INATOMIC_BASE + preempt_offset);
+}
+
+void __might_sleep(char *file, int line, int preempt_offset)
{
#ifdef in_atomic
static unsigned long prev_jiffy; /* ratelimiting */
- if ((!in_atomic() && !irqs_disabled()) ||
- system_state != SYSTEM_RUNNING || oops_in_progress)
+ if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
+ system_state != SYSTEM_RUNNING || oops_in_progress)
return;
if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
return;
@@ -10581,3 +10903,113 @@ struct cgroup_subsys cpuacct_subsys = {
.subsys_id = cpuacct_subsys_id,
};
#endif /* CONFIG_CGROUP_CPUACCT */
+
+#ifndef CONFIG_SMP
+
+int rcu_expedited_torture_stats(char *page)
+{
+ return 0;
+}
+EXPORT_SYMBOL_GPL(rcu_expedited_torture_stats);
+
+void synchronize_sched_expedited(void)
+{
+}
+EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
+
+#else /* #ifndef CONFIG_SMP */
+
+static DEFINE_PER_CPU(struct migration_req, rcu_migration_req);
+static DEFINE_MUTEX(rcu_sched_expedited_mutex);
+
+#define RCU_EXPEDITED_STATE_POST -2
+#define RCU_EXPEDITED_STATE_IDLE -1
+
+static int rcu_expedited_state = RCU_EXPEDITED_STATE_IDLE;
+
+int rcu_expedited_torture_stats(char *page)
+{
+ int cnt = 0;
+ int cpu;
+
+ cnt += sprintf(&page[cnt], "state: %d /", rcu_expedited_state);
+ for_each_online_cpu(cpu) {
+ cnt += sprintf(&page[cnt], " %d:%d",
+ cpu, per_cpu(rcu_migration_req, cpu).dest_cpu);
+ }
+ cnt += sprintf(&page[cnt], "\n");
+ return cnt;
+}
+EXPORT_SYMBOL_GPL(rcu_expedited_torture_stats);
+
+static long synchronize_sched_expedited_count;
+
+/*
+ * Wait for an rcu-sched grace period to elapse, but use "big hammer"
+ * approach to force grace period to end quickly. This consumes
+ * significant time on all CPUs, and is thus not recommended for
+ * any sort of common-case code.
+ *
+ * Note that it is illegal to call this function while holding any
+ * lock that is acquired by a CPU-hotplug notifier. Failing to
+ * observe this restriction will result in deadlock.
+ */
+void synchronize_sched_expedited(void)
+{
+ int cpu;
+ unsigned long flags;
+ bool need_full_sync = 0;
+ struct rq *rq;
+ struct migration_req *req;
+ long snap;
+ int trycount = 0;
+
+ smp_mb(); /* ensure prior mod happens before capturing snap. */
+ snap = ACCESS_ONCE(synchronize_sched_expedited_count) + 1;
+ get_online_cpus();
+ while (!mutex_trylock(&rcu_sched_expedited_mutex)) {
+ put_online_cpus();
+ if (trycount++ < 10)
+ udelay(trycount * num_online_cpus());
+ else {
+ synchronize_sched();
+ return;
+ }
+ if (ACCESS_ONCE(synchronize_sched_expedited_count) - snap > 0) {
+ smp_mb(); /* ensure test happens before caller kfree */
+ return;
+ }
+ get_online_cpus();
+ }
+ rcu_expedited_state = RCU_EXPEDITED_STATE_POST;
+ for_each_online_cpu(cpu) {
+ rq = cpu_rq(cpu);
+ req = &per_cpu(rcu_migration_req, cpu);
+ init_completion(&req->done);
+ req->task = NULL;
+ req->dest_cpu = RCU_MIGRATION_NEED_QS;
+ spin_lock_irqsave(&rq->lock, flags);
+ list_add(&req->list, &rq->migration_queue);
+ spin_unlock_irqrestore(&rq->lock, flags);
+ wake_up_process(rq->migration_thread);
+ }
+ for_each_online_cpu(cpu) {
+ rcu_expedited_state = cpu;
+ req = &per_cpu(rcu_migration_req, cpu);
+ rq = cpu_rq(cpu);
+ wait_for_completion(&req->done);
+ spin_lock_irqsave(&rq->lock, flags);
+ if (unlikely(req->dest_cpu == RCU_MIGRATION_MUST_SYNC))
+ need_full_sync = 1;
+ req->dest_cpu = RCU_MIGRATION_IDLE;
+ spin_unlock_irqrestore(&rq->lock, flags);
+ }
+ rcu_expedited_state = RCU_EXPEDITED_STATE_IDLE;
+ mutex_unlock(&rcu_sched_expedited_mutex);
+ put_online_cpus();
+ if (need_full_sync)
+ synchronize_sched();
+}
+EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
+
+#endif /* #else #ifndef CONFIG_SMP */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-21 18:52:17 +0000