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-rw-r--r--kernel/sched.c870
1 files changed, 228 insertions, 642 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 34bcc5bc120..4e2f6033565 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -75,16 +75,6 @@
#include <asm/irq_regs.h>
/*
- * Scheduler clock - returns current time in nanosec units.
- * This is default implementation.
- * Architectures and sub-architectures can override this.
- */
-unsigned long long __attribute__((weak)) sched_clock(void)
-{
- return (unsigned long long)jiffies * (NSEC_PER_SEC / HZ);
-}
-
-/*
* Convert user-nice values [ -20 ... 0 ... 19 ]
* to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
* and back.
@@ -146,7 +136,7 @@ static inline void sg_inc_cpu_power(struct sched_group *sg, u32 val)
static inline int rt_policy(int policy)
{
- if (unlikely(policy == SCHED_FIFO) || unlikely(policy == SCHED_RR))
+ if (unlikely(policy == SCHED_FIFO || policy == SCHED_RR))
return 1;
return 0;
}
@@ -242,6 +232,12 @@ static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b)
}
#endif
+/*
+ * sched_domains_mutex serializes calls to arch_init_sched_domains,
+ * detach_destroy_domains and partition_sched_domains.
+ */
+static DEFINE_MUTEX(sched_domains_mutex);
+
#ifdef CONFIG_GROUP_SCHED
#include <linux/cgroup.h>
@@ -308,9 +304,6 @@ static DEFINE_PER_CPU(struct rt_rq, init_rt_rq) ____cacheline_aligned_in_smp;
*/
static DEFINE_SPINLOCK(task_group_lock);
-/* doms_cur_mutex serializes access to doms_cur[] array */
-static DEFINE_MUTEX(doms_cur_mutex);
-
#ifdef CONFIG_FAIR_GROUP_SCHED
#ifdef CONFIG_USER_SCHED
# define INIT_TASK_GROUP_LOAD (2*NICE_0_LOAD)
@@ -318,7 +311,16 @@ static DEFINE_MUTEX(doms_cur_mutex);
# define INIT_TASK_GROUP_LOAD NICE_0_LOAD
#endif
+/*
+ * A weight of 0 or 1 can cause arithmetics problems.
+ * A weight of a cfs_rq is the sum of weights of which entities
+ * are queued on this cfs_rq, so a weight of a entity should not be
+ * too large, so as the shares value of a task group.
+ * (The default weight is 1024 - so there's no practical
+ * limitation from this.)
+ */
#define MIN_SHARES 2
+#define MAX_SHARES (1UL << 18)
static int init_task_group_load = INIT_TASK_GROUP_LOAD;
#endif
@@ -358,21 +360,9 @@ static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
#endif
}
-static inline void lock_doms_cur(void)
-{
- mutex_lock(&doms_cur_mutex);
-}
-
-static inline void unlock_doms_cur(void)
-{
- mutex_unlock(&doms_cur_mutex);
-}
-
#else
static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
-static inline void lock_doms_cur(void) { }
-static inline void unlock_doms_cur(void) { }
#endif /* CONFIG_GROUP_SCHED */
@@ -411,43 +401,6 @@ struct cfs_rq {
*/
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
};
@@ -560,13 +513,7 @@ struct rq {
unsigned long next_balance;
struct mm_struct *prev_mm;
- u64 clock, prev_clock_raw;
- s64 clock_max_delta;
-
- unsigned int clock_warps, clock_overflows, clock_underflows;
- u64 idle_clock;
- unsigned int clock_deep_idle_events;
- u64 tick_timestamp;
+ u64 clock;
atomic_t nr_iowait;
@@ -631,82 +578,6 @@ static inline int cpu_of(struct rq *rq)
#endif
}
-#ifdef CONFIG_NO_HZ
-static inline bool nohz_on(int cpu)
-{
- return tick_get_tick_sched(cpu)->nohz_mode != NOHZ_MODE_INACTIVE;
-}
-
-static inline u64 max_skipped_ticks(struct rq *rq)
-{
- return nohz_on(cpu_of(rq)) ? jiffies - rq->last_tick_seen + 2 : 1;
-}
-
-static inline void update_last_tick_seen(struct rq *rq)
-{
- rq->last_tick_seen = jiffies;
-}
-#else
-static inline u64 max_skipped_ticks(struct rq *rq)
-{
- return 1;
-}
-
-static inline void update_last_tick_seen(struct rq *rq)
-{
-}
-#endif
-
-/*
- * Update the per-runqueue clock, as finegrained as the platform can give
- * us, but without assuming monotonicity, etc.:
- */
-static void __update_rq_clock(struct rq *rq)
-{
- u64 prev_raw = rq->prev_clock_raw;
- u64 now = sched_clock();
- s64 delta = now - prev_raw;
- u64 clock = rq->clock;
-
-#ifdef CONFIG_SCHED_DEBUG
- WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
-#endif
- /*
- * Protect against sched_clock() occasionally going backwards:
- */
- if (unlikely(delta < 0)) {
- clock++;
- rq->clock_warps++;
- } else {
- /*
- * Catch too large forward jumps too:
- */
- u64 max_jump = max_skipped_ticks(rq) * TICK_NSEC;
- u64 max_time = rq->tick_timestamp + max_jump;
-
- if (unlikely(clock + delta > max_time)) {
- if (clock < max_time)
- clock = max_time;
- else
- clock++;
- rq->clock_overflows++;
- } else {
- if (unlikely(delta > rq->clock_max_delta))
- rq->clock_max_delta = delta;
- clock += delta;
- }
- }
-
- rq->prev_clock_raw = now;
- rq->clock = clock;
-}
-
-static void update_rq_clock(struct rq *rq)
-{
- if (likely(smp_processor_id() == cpu_of(rq)))
- __update_rq_clock(rq);
-}
-
/*
* The domain tree (rq->sd) is protected by RCU's quiescent state transition.
* See detach_destroy_domains: synchronize_sched for details.
@@ -722,6 +593,11 @@ static void update_rq_clock(struct rq *rq)
#define task_rq(p) cpu_rq(task_cpu(p))
#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
+static inline void update_rq_clock(struct rq *rq)
+{
+ rq->clock = sched_clock_cpu(cpu_of(rq));
+}
+
/*
* Tunables that become constants when CONFIG_SCHED_DEBUG is off:
*/
@@ -757,14 +633,14 @@ const_debug unsigned int sysctl_sched_features =
#define SCHED_FEAT(name, enabled) \
#name ,
-__read_mostly char *sched_feat_names[] = {
+static __read_mostly char *sched_feat_names[] = {
#include "sched_features.h"
NULL
};
#undef SCHED_FEAT
-int sched_feat_open(struct inode *inode, struct file *filp)
+static int sched_feat_open(struct inode *inode, struct file *filp)
{
filp->private_data = inode->i_private;
return 0;
@@ -899,7 +775,7 @@ static inline u64 global_rt_runtime(void)
return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
}
-static const unsigned long long time_sync_thresh = 100000;
+unsigned long long time_sync_thresh = 100000;
static DEFINE_PER_CPU(unsigned long long, time_offset);
static DEFINE_PER_CPU(unsigned long long, prev_cpu_time);
@@ -913,11 +789,14 @@ static DEFINE_PER_CPU(unsigned long long, prev_cpu_time);
static DEFINE_SPINLOCK(time_sync_lock);
static unsigned long long prev_global_time;
-static unsigned long long __sync_cpu_clock(cycles_t time, int cpu)
+static unsigned long long __sync_cpu_clock(unsigned long long time, int cpu)
{
- unsigned long flags;
-
- spin_lock_irqsave(&time_sync_lock, flags);
+ /*
+ * We want this inlined, to not get tracer function calls
+ * in this critical section:
+ */
+ spin_acquire(&time_sync_lock.dep_map, 0, 0, _THIS_IP_);
+ __raw_spin_lock(&time_sync_lock.raw_lock);
if (time < prev_global_time) {
per_cpu(time_offset, cpu) += prev_global_time - time;
@@ -926,7 +805,8 @@ static unsigned long long __sync_cpu_clock(cycles_t time, int cpu)
prev_global_time = time;
}
- spin_unlock_irqrestore(&time_sync_lock, flags);
+ __raw_spin_unlock(&time_sync_lock.raw_lock);
+ spin_release(&time_sync_lock.dep_map, 1, _THIS_IP_);
return time;
}
@@ -934,8 +814,6 @@ static unsigned long long __sync_cpu_clock(cycles_t time, int cpu)
static unsigned long long __cpu_clock(int cpu)
{
unsigned long long now;
- unsigned long flags;
- struct rq *rq;
/*
* Only call sched_clock() if the scheduler has already been
@@ -944,11 +822,7 @@ static unsigned long long __cpu_clock(int cpu)
if (unlikely(!scheduler_running))
return 0;
- local_irq_save(flags);
- rq = cpu_rq(cpu);
- update_rq_clock(rq);
- now = rq->clock;
- local_irq_restore(flags);
+ now = sched_clock_cpu(cpu);
return now;
}
@@ -960,13 +834,18 @@ static unsigned long long __cpu_clock(int cpu)
unsigned long long cpu_clock(int cpu)
{
unsigned long long prev_cpu_time, time, delta_time;
+ unsigned long flags;
+ local_irq_save(flags);
prev_cpu_time = per_cpu(prev_cpu_time, cpu);
time = __cpu_clock(cpu) + per_cpu(time_offset, cpu);
delta_time = time-prev_cpu_time;
- if (unlikely(delta_time > time_sync_thresh))
+ if (unlikely(delta_time > time_sync_thresh)) {
time = __sync_cpu_clock(time, cpu);
+ per_cpu(prev_cpu_time, cpu) = time;
+ }
+ local_irq_restore(flags);
return time;
}
@@ -1117,43 +996,6 @@ static struct rq *this_rq_lock(void)
return rq;
}
-/*
- * We are going deep-idle (irqs are disabled):
- */
-void sched_clock_idle_sleep_event(void)
-{
- struct rq *rq = cpu_rq(smp_processor_id());
-
- spin_lock(&rq->lock);
- __update_rq_clock(rq);
- spin_unlock(&rq->lock);
- rq->clock_deep_idle_events++;
-}
-EXPORT_SYMBOL_GPL(sched_clock_idle_sleep_event);
-
-/*
- * We just idled delta nanoseconds (called with irqs disabled):
- */
-void sched_clock_idle_wakeup_event(u64 delta_ns)
-{
- struct rq *rq = cpu_rq(smp_processor_id());
- u64 now = sched_clock();
-
- rq->idle_clock += delta_ns;
- /*
- * Override the previous timestamp and ignore all
- * sched_clock() deltas that occured while we idled,
- * and use the PM-provided delta_ns to advance the
- * rq clock:
- */
- spin_lock(&rq->lock);
- rq->prev_clock_raw = now;
- rq->clock += delta_ns;
- spin_unlock(&rq->lock);
- touch_softlockup_watchdog();
-}
-EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
-
static void __resched_task(struct task_struct *p, int tif_bit);
static inline void resched_task(struct task_struct *p)
@@ -1189,6 +1031,7 @@ static inline void resched_rq(struct rq *rq)
enum {
HRTICK_SET, /* re-programm hrtick_timer */
HRTICK_RESET, /* not a new slice */
+ HRTICK_BLOCK, /* stop hrtick operations */
};
/*
@@ -1200,6 +1043,8 @@ static inline int hrtick_enabled(struct rq *rq)
{
if (!sched_feat(HRTICK))
return 0;
+ if (unlikely(test_bit(HRTICK_BLOCK, &rq->hrtick_flags)))
+ return 0;
return hrtimer_is_hres_active(&rq->hrtick_timer);
}
@@ -1275,14 +1120,72 @@ static enum hrtimer_restart hrtick(struct hrtimer *timer)
WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
spin_lock(&rq->lock);
- __update_rq_clock(rq);
+ update_rq_clock(rq);
rq->curr->sched_class->task_tick(rq, rq->curr, 1);
spin_unlock(&rq->lock);
return HRTIMER_NORESTART;
}
-static inline void init_rq_hrtick(struct rq *rq)
+#ifdef CONFIG_SMP
+static void hotplug_hrtick_disable(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long flags;
+
+ spin_lock_irqsave(&rq->lock, flags);
+ rq->hrtick_flags = 0;
+ __set_bit(HRTICK_BLOCK, &rq->hrtick_flags);
+ spin_unlock_irqrestore(&rq->lock, flags);
+
+ hrtick_clear(rq);
+}
+
+static void hotplug_hrtick_enable(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+ unsigned long flags;
+
+ spin_lock_irqsave(&rq->lock, flags);
+ __clear_bit(HRTICK_BLOCK, &rq->hrtick_flags);
+ spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+static int
+hotplug_hrtick(struct notifier_block *nfb, unsigned long action, void *hcpu)
+{
+ int cpu = (int)(long)hcpu;
+
+ switch (action) {
+ case CPU_UP_CANCELED:
+ case CPU_UP_CANCELED_FROZEN:
+ case CPU_DOWN_PREPARE:
+ case CPU_DOWN_PREPARE_FROZEN:
+ case CPU_DEAD:
+ case CPU_DEAD_FROZEN:
+ hotplug_hrtick_disable(cpu);
+ return NOTIFY_OK;
+
+ case CPU_UP_PREPARE:
+ case CPU_UP_PREPARE_FROZEN:
+ case CPU_DOWN_FAILED:
+ case CPU_DOWN_FAILED_FROZEN:
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ hotplug_hrtick_enable(cpu);
+ return NOTIFY_OK;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static void init_hrtick(void)
+{
+ hotcpu_notifier(hotplug_hrtick, 0);
+}
+#endif /* CONFIG_SMP */
+
+static void init_rq_hrtick(struct rq *rq)
{
rq->hrtick_flags = 0;
hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
@@ -1319,6 +1222,10 @@ static inline void init_rq_hrtick(struct rq *rq)
void hrtick_resched(void)
{
}
+
+static inline void init_hrtick(void)
+{
+}
#endif
/*
@@ -1429,17 +1336,19 @@ static void __resched_task(struct task_struct *p, int tif_bit)
*/
#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;
- if (unlikely(!lw->inv_weight))
- lw->inv_weight = (WMULT_CONST-lw->weight/2) / (lw->weight+1);
+ if (!lw->inv_weight) {
+ if (BITS_PER_LONG > 32 && unlikely(lw->weight >= WMULT_CONST))
+ lw->inv_weight = 1;
+ else
+ lw->inv_weight = 1 + (WMULT_CONST-lw->weight/2)
+ / (lw->weight+1);
+ }
tmp = (u64)delta_exec * weight;
/*
@@ -1454,6 +1363,12 @@ calc_delta_mine(unsigned long delta_exec, unsigned long weight,
return (unsigned long)min(tmp, (u64)(unsigned long)LONG_MAX);
}
+static inline unsigned long
+calc_delta_fair(unsigned long delta_exec, struct load_weight *lw)
+{
+ return calc_delta_mine(delta_exec, NICE_0_LOAD, lw);
+}
+
static inline void update_load_add(struct load_weight *lw, unsigned long inc)
{
lw->weight += inc;
@@ -1566,324 +1481,6 @@ static unsigned long source_load(int cpu, int type);
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;
-
- __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
@@ -1904,14 +1501,26 @@ static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
#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)
@@ -2003,7 +1612,7 @@ static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
rq->nr_uninterruptible--;
enqueue_task(rq, p, wakeup);
- inc_nr_running(rq);
+ inc_nr_running(p, rq);
}
/*
@@ -2015,7 +1624,7 @@ static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep)
rq->nr_uninterruptible++;
dequeue_task(rq, p, sleep);
- dec_nr_running(rq);
+ dec_nr_running(p, rq);
}
/**
@@ -2668,7 +2277,7 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
* 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
@@ -3659,12 +3268,9 @@ static int load_balance(int this_cpu, struct rq *this_rq,
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,
@@ -3780,9 +3386,8 @@ redo:
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]);
@@ -3797,13 +3402,8 @@ out_one_pinned:
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;
}
/*
@@ -4339,8 +3939,10 @@ void account_system_time(struct task_struct *p, int hardirq_offset,
struct rq *rq = this_rq();
cputime64_t tmp;
- if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0))
- return account_guest_time(p, cputime);
+ if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) {
+ account_guest_time(p, cputime);
+ return;
+ }
p->stime = cputime_add(p->stime, cputime);
@@ -4404,19 +4006,11 @@ void scheduler_tick(void)
int cpu = smp_processor_id();
struct rq *rq = cpu_rq(cpu);
struct task_struct *curr = rq->curr;
- u64 next_tick = rq->tick_timestamp + TICK_NSEC;
+
+ sched_clock_tick();
spin_lock(&rq->lock);
- __update_rq_clock(rq);
- /*
- * Let rq->clock advance by at least TICK_NSEC:
- */
- if (unlikely(rq->clock < next_tick)) {
- rq->clock = next_tick;
- rq->clock_underflows++;
- }
- rq->tick_timestamp = rq->clock;
- update_last_tick_seen(rq);
+ update_rq_clock(rq);
update_cpu_load(rq);
curr->sched_class->task_tick(rq, curr, 0);
spin_unlock(&rq->lock);
@@ -4495,7 +4089,7 @@ static inline void schedule_debug(struct task_struct *prev)
* schedule() atomically, we ignore that path for now.
* Otherwise, whine if we are scheduling when we should not be.
*/
- if (unlikely(in_atomic_preempt_off()) && unlikely(!prev->exit_state))
+ if (unlikely(in_atomic_preempt_off() && !prev->exit_state))
__schedule_bug(prev);
profile_hit(SCHED_PROFILING, __builtin_return_address(0));
@@ -4570,17 +4164,15 @@ need_resched_nonpreemptible:
* Do the rq-clock update outside the rq lock:
*/
local_irq_disable();
- __update_rq_clock(rq);
+ update_rq_clock(rq);
spin_lock(&rq->lock);
clear_tsk_need_resched(prev);
if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
- if (unlikely((prev->state & TASK_INTERRUPTIBLE) &&
- signal_pending(prev))) {
+ if (unlikely(signal_pending_state(prev->state, prev)))
prev->state = TASK_RUNNING;
- } else {
+ else
deactivate_task(rq, prev, 1);
- }
switch_count = &prev->nvcsw;
}
@@ -4595,9 +4187,9 @@ need_resched_nonpreemptible:
prev->sched_class->put_prev_task(rq, prev);
next = pick_next_task(rq, prev);
- sched_info_switch(prev, next);
-
if (likely(prev != next)) {
+ sched_info_switch(prev, next);
+
rq->nr_switches++;
rq->curr = next;
++*switch_count;
@@ -4632,8 +4224,6 @@ EXPORT_SYMBOL(schedule);
asmlinkage void __sched preempt_schedule(void)
{
struct thread_info *ti = current_thread_info();
- struct task_struct *task = current;
- int saved_lock_depth;
/*
* If there is a non-zero preempt_count or interrupts are disabled,
@@ -4644,16 +4234,7 @@ asmlinkage void __sched preempt_schedule(void)
do {
add_preempt_count(PREEMPT_ACTIVE);
-
- /*
- * We keep the big kernel semaphore locked, but we
- * clear ->lock_depth so that schedule() doesnt
- * auto-release the semaphore:
- */
- saved_lock_depth = task->lock_depth;
- task->lock_depth = -1;
schedule();
- task->lock_depth = saved_lock_depth;
sub_preempt_count(PREEMPT_ACTIVE);
/*
@@ -4674,26 +4255,15 @@ EXPORT_SYMBOL(preempt_schedule);
asmlinkage void __sched preempt_schedule_irq(void)
{
struct thread_info *ti = current_thread_info();
- struct task_struct *task = current;
- int saved_lock_depth;
/* Catch callers which need to be fixed */
BUG_ON(ti->preempt_count || !irqs_disabled());
do {
add_preempt_count(PREEMPT_ACTIVE);
-
- /*
- * We keep the big kernel semaphore locked, but we
- * clear ->lock_depth so that schedule() doesnt
- * auto-release the semaphore:
- */
- saved_lock_depth = task->lock_depth;
- task->lock_depth = -1;
local_irq_enable();
schedule();
local_irq_disable();
- task->lock_depth = saved_lock_depth;
sub_preempt_count(PREEMPT_ACTIVE);
/*
@@ -4828,22 +4398,20 @@ do_wait_for_common(struct completion *x, long timeout, int state)
signal_pending(current)) ||
(state == TASK_KILLABLE &&
fatal_signal_pending(current))) {
- __remove_wait_queue(&x->wait, &wait);
- return -ERESTARTSYS;
+ timeout = -ERESTARTSYS;
+ break;
}
__set_current_state(state);
spin_unlock_irq(&x->wait.lock);
timeout = schedule_timeout(timeout);
spin_lock_irq(&x->wait.lock);
- if (!timeout) {
- __remove_wait_queue(&x->wait, &wait);
- return timeout;
- }
- } while (!x->done);
+ } while (!x->done && timeout);
__remove_wait_queue(&x->wait, &wait);
+ if (!x->done)
+ return timeout;
}
x->done--;
- return timeout;
+ return timeout ?: 1;
}
static long __sched
@@ -5018,8 +4586,10 @@ void set_user_nice(struct task_struct *p, long nice)
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);
@@ -5029,6 +4599,7 @@ void set_user_nice(struct task_struct *p, long nice)
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:
@@ -5612,7 +5183,6 @@ static void __cond_resched(void)
} while (need_resched());
}
-#if !defined(CONFIG_PREEMPT) || defined(CONFIG_PREEMPT_VOLUNTARY)
int __sched _cond_resched(void)
{
if (need_resched() && !(preempt_count() & PREEMPT_ACTIVE) &&
@@ -5623,7 +5193,6 @@ int __sched _cond_resched(void)
return 0;
}
EXPORT_SYMBOL(_cond_resched);
-#endif
/*
* cond_resched_lock() - if a reschedule is pending, drop the given lock,
@@ -5918,8 +5487,11 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu)
spin_unlock_irqrestore(&rq->lock, flags);
/* Set the preempt count _outside_ the spinlocks! */
+#if defined(CONFIG_PREEMPT)
+ task_thread_info(idle)->preempt_count = (idle->lock_depth >= 0);
+#else
task_thread_info(idle)->preempt_count = 0;
-
+#endif
/*
* The idle tasks have their own, simple scheduling class:
*/
@@ -6050,10 +5622,10 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
double_rq_lock(rq_src, rq_dest);
/* Already moved. */
if (task_cpu(p) != src_cpu)
- goto out;
+ goto done;
/* Affinity changed (again). */
if (!cpu_isset(dest_cpu, p->cpus_allowed))
- goto out;
+ goto fail;
on_rq = p->se.on_rq;
if (on_rq)
@@ -6064,8 +5636,9 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
activate_task(rq_dest, p, 0);
check_preempt_curr(rq_dest, p);
}
+done:
ret = 1;
-out:
+fail:
double_rq_unlock(rq_src, rq_dest);
return ret;
}
@@ -6315,6 +5888,7 @@ static void migrate_dead_tasks(unsigned int dead_cpu)
next = pick_next_task(rq, rq->curr);
if (!next)
break;
+ next->sched_class->put_prev_task(rq, next);
migrate_dead(dead_cpu, next);
}
@@ -7305,7 +6879,12 @@ static int default_relax_domain_level = -1;
static int __init setup_relax_domain_level(char *str)
{
- default_relax_domain_level = simple_strtoul(str, NULL, 0);
+ unsigned long val;
+
+ val = simple_strtoul(str, NULL, 0);
+ if (val < SD_LV_MAX)
+ default_relax_domain_level = val;
+
return 1;
}
__setup("relax_domain_level=", setup_relax_domain_level);
@@ -7402,7 +6981,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
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;
@@ -7413,7 +6991,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
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;
@@ -7425,7 +7002,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
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;
@@ -7437,7 +7013,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
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;
@@ -7450,7 +7025,6 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
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;
@@ -7654,8 +7228,8 @@ static int build_sched_domains(const cpumask_t *cpu_map)
static cpumask_t *doms_cur; /* current sched domains */
static int ndoms_cur; /* number of sched domains in 'doms_cur' */
-static struct sched_domain_attr *dattr_cur; /* attribues of custom domains
- in 'doms_cur' */
+static struct sched_domain_attr *dattr_cur;
+ /* attribues of custom domains in 'doms_cur' */
/*
* Special case: If a kmalloc of a doms_cur partition (array of
@@ -7669,6 +7243,18 @@ void __attribute__((weak)) arch_update_cpu_topology(void)
}
/*
+ * Free current domain masks.
+ * Called after all cpus are attached to NULL domain.
+ */
+static void free_sched_domains(void)
+{
+ ndoms_cur = 0;
+ if (doms_cur != &fallback_doms)
+ kfree(doms_cur);
+ doms_cur = &fallback_doms;
+}
+
+/*
* Set up scheduler domains and groups. Callers must hold the hotplug lock.
* For now this just excludes isolated cpus, but could be used to
* exclude other special cases in the future.
@@ -7755,7 +7341,7 @@ void partition_sched_domains(int ndoms_new, cpumask_t *doms_new,
{
int i, j;
- lock_doms_cur();
+ mutex_lock(&sched_domains_mutex);
/* always unregister in case we don't destroy any domains */
unregister_sched_domain_sysctl();
@@ -7804,7 +7390,7 @@ match2:
register_sched_domain_sysctl();
- unlock_doms_cur();
+ mutex_unlock(&sched_domains_mutex);
}
#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
@@ -7813,8 +7399,11 @@ int arch_reinit_sched_domains(void)
int err;
get_online_cpus();
+ mutex_lock(&sched_domains_mutex);
detach_destroy_domains(&cpu_online_map);
+ free_sched_domains();
err = arch_init_sched_domains(&cpu_online_map);
+ mutex_unlock(&sched_domains_mutex);
put_online_cpus();
return err;
@@ -7898,6 +7487,7 @@ static int update_sched_domains(struct notifier_block *nfb,
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
detach_destroy_domains(&cpu_online_map);
+ free_sched_domains();
return NOTIFY_OK;
case CPU_UP_CANCELED:
@@ -7916,8 +7506,16 @@ static int update_sched_domains(struct notifier_block *nfb,
return NOTIFY_DONE;
}
+#ifndef CONFIG_CPUSETS
+ /*
+ * Create default domain partitioning if cpusets are disabled.
+ * Otherwise we let cpusets rebuild the domains based on the
+ * current setup.
+ */
+
/* The hotplug lock is already held by cpu_up/cpu_down */
arch_init_sched_domains(&cpu_online_map);
+#endif
return NOTIFY_OK;
}
@@ -7932,13 +7530,16 @@ void __init sched_init_smp(void)
BUG_ON(sched_group_nodes_bycpu == NULL);
#endif
get_online_cpus();
+ mutex_lock(&sched_domains_mutex);
arch_init_sched_domains(&cpu_online_map);
cpus_andnot(non_isolated_cpus, cpu_possible_map, cpu_isolated_map);
if (cpus_empty(non_isolated_cpus))
cpu_set(smp_processor_id(), non_isolated_cpus);
+ mutex_unlock(&sched_domains_mutex);
put_online_cpus();
/* XXX: Theoretical race here - CPU may be hotplugged now */
hotcpu_notifier(update_sched_domains, 0);
+ init_hrtick();
/* Move init over to a non-isolated CPU */
if (set_cpus_allowed_ptr(current, &non_isolated_cpus) < 0)
@@ -8025,7 +7626,7 @@ static void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
se->my_q = cfs_rq;
se->load.weight = tg->shares;
- se->load.inv_weight = div64_u64(1ULL<<32, se->load.weight);
+ se->load.inv_weight = 0;
se->parent = parent;
}
#endif
@@ -8054,7 +7655,6 @@ static void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
else
rt_se->rt_rq = parent->my_q;
- rt_se->rt_rq = &rq->rt;
rt_se->my_q = rt_rq;
rt_se->parent = parent;
INIT_LIST_HEAD(&rt_se->run_list);
@@ -8115,7 +7715,6 @@ void __init sched_init(void)
}
#ifdef CONFIG_SMP
- init_aggregate();
init_defrootdomain();
#endif
@@ -8149,8 +7748,6 @@ void __init sched_init(void)
spin_lock_init(&rq->lock);
lockdep_set_class(&rq->lock, &rq->rq_lock_key);
rq->nr_running = 0;
- rq->clock = 1;
- update_last_tick_seen(rq);
init_cfs_rq(&rq->cfs, rq);
init_rt_rq(&rq->rt, rq);
#ifdef CONFIG_FAIR_GROUP_SCHED
@@ -8294,6 +7891,7 @@ EXPORT_SYMBOL(__might_sleep);
static void normalize_task(struct rq *rq, struct task_struct *p)
{
int on_rq;
+
update_rq_clock(rq);
on_rq = p->se.on_rq;
if (on_rq)
@@ -8325,7 +7923,6 @@ void normalize_rt_tasks(void)
p->se.sleep_start = 0;
p->se.block_start = 0;
#endif
- task_rq(p)->clock = 0;
if (!rt_task(p)) {
/*
@@ -8682,31 +8279,25 @@ void sched_move_task(struct task_struct *tsk)
#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);
se->load.weight = shares;
- se->load.inv_weight = div64_u64((1ULL<<32), shares);
+ se->load.inv_weight = 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);
@@ -8722,13 +8313,10 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
if (!tg->se[0])
return -EINVAL;
- /*
- * A weight of 0 or 1 can cause arithmetics problems.
- * (The default weight is 1024 - so there's no practical
- * limitation from this.)
- */
if (shares < MIN_SHARES)
shares = MIN_SHARES;
+ else if (shares > MAX_SHARES)
+ shares = MAX_SHARES;
mutex_lock(&shares_mutex);
if (tg->shares == shares)
@@ -8748,13 +8336,8 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
* 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);
- set_se_shares(tg->se[i], shares/nr_cpu_ids);
- }
+ for_each_possible_cpu(i)
+ set_se_shares(tg->se[i], shares);
/*
* Enable load balance activity on this group, by inserting it back on
@@ -8793,7 +8376,7 @@ static unsigned long to_ratio(u64 period, u64 runtime)
#ifdef CONFIG_CGROUP_SCHED
static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
{
- struct task_group *tgi, *parent = tg->parent;
+ struct task_group *tgi, *parent = tg ? tg->parent : NULL;
unsigned long total = 0;
if (!parent) {
@@ -8920,6 +8503,9 @@ int sched_group_set_rt_period(struct task_group *tg, long rt_period_us)
rt_period = (u64)rt_period_us * NSEC_PER_USEC;
rt_runtime = tg->rt_bandwidth.rt_runtime;
+ if (rt_period == 0)
+ return -EINVAL;
+
return tg_set_bandwidth(tg, rt_period, rt_runtime);
}
@@ -9072,7 +8658,7 @@ static u64 cpu_shares_read_u64(struct cgroup *cgrp, struct cftype *cft)
#endif
#ifdef CONFIG_RT_GROUP_SCHED
-static ssize_t cpu_rt_runtime_write(struct cgroup *cgrp, struct cftype *cft,
+static int cpu_rt_runtime_write(struct cgroup *cgrp, struct cftype *cft,
s64 val)
{
return sched_group_set_rt_runtime(cgroup_tg(cgrp), val);