|  | 
 | #include <linux/sched.h> | 
 | #include <linux/mutex.h> | 
 | #include <linux/spinlock.h> | 
 | #include <linux/stop_machine.h> | 
 |  | 
 | #include "cpupri.h" | 
 |  | 
 | extern __read_mostly int scheduler_running; | 
 |  | 
 | /* | 
 |  * Convert user-nice values [ -20 ... 0 ... 19 ] | 
 |  * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ], | 
 |  * and back. | 
 |  */ | 
 | #define NICE_TO_PRIO(nice)	(MAX_RT_PRIO + (nice) + 20) | 
 | #define PRIO_TO_NICE(prio)	((prio) - MAX_RT_PRIO - 20) | 
 | #define TASK_NICE(p)		PRIO_TO_NICE((p)->static_prio) | 
 |  | 
 | /* | 
 |  * 'User priority' is the nice value converted to something we | 
 |  * can work with better when scaling various scheduler parameters, | 
 |  * it's a [ 0 ... 39 ] range. | 
 |  */ | 
 | #define USER_PRIO(p)		((p)-MAX_RT_PRIO) | 
 | #define TASK_USER_PRIO(p)	USER_PRIO((p)->static_prio) | 
 | #define MAX_USER_PRIO		(USER_PRIO(MAX_PRIO)) | 
 |  | 
 | /* | 
 |  * Helpers for converting nanosecond timing to jiffy resolution | 
 |  */ | 
 | #define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) | 
 |  | 
 | #define NICE_0_LOAD		SCHED_LOAD_SCALE | 
 | #define NICE_0_SHIFT		SCHED_LOAD_SHIFT | 
 |  | 
 | /* | 
 |  * These are the 'tuning knobs' of the scheduler: | 
 |  */ | 
 |  | 
 | /* | 
 |  * single value that denotes runtime == period, ie unlimited time. | 
 |  */ | 
 | #define RUNTIME_INF	((u64)~0ULL) | 
 |  | 
 | static inline int rt_policy(int policy) | 
 | { | 
 | 	if (policy == SCHED_FIFO || policy == SCHED_RR) | 
 | 		return 1; | 
 | 	return 0; | 
 | } | 
 |  | 
 | static inline int task_has_rt_policy(struct task_struct *p) | 
 | { | 
 | 	return rt_policy(p->policy); | 
 | } | 
 |  | 
 | /* | 
 |  * This is the priority-queue data structure of the RT scheduling class: | 
 |  */ | 
 | struct rt_prio_array { | 
 | 	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ | 
 | 	struct list_head queue[MAX_RT_PRIO]; | 
 | }; | 
 |  | 
 | struct rt_bandwidth { | 
 | 	/* nests inside the rq lock: */ | 
 | 	raw_spinlock_t		rt_runtime_lock; | 
 | 	ktime_t			rt_period; | 
 | 	u64			rt_runtime; | 
 | 	struct hrtimer		rt_period_timer; | 
 | }; | 
 |  | 
 | extern struct mutex sched_domains_mutex; | 
 |  | 
 | #ifdef CONFIG_CGROUP_SCHED | 
 |  | 
 | #include <linux/cgroup.h> | 
 |  | 
 | struct cfs_rq; | 
 | struct rt_rq; | 
 |  | 
 | extern struct list_head task_groups; | 
 |  | 
 | struct cfs_bandwidth { | 
 | #ifdef CONFIG_CFS_BANDWIDTH | 
 | 	raw_spinlock_t lock; | 
 | 	ktime_t period; | 
 | 	u64 quota, runtime; | 
 | 	s64 hierarchal_quota; | 
 | 	u64 runtime_expires; | 
 |  | 
 | 	int idle, timer_active; | 
 | 	struct hrtimer period_timer, slack_timer; | 
 | 	struct list_head throttled_cfs_rq; | 
 |  | 
 | 	/* statistics */ | 
 | 	int nr_periods, nr_throttled; | 
 | 	u64 throttled_time; | 
 | #endif | 
 | }; | 
 |  | 
 | /* task group related information */ | 
 | struct task_group { | 
 | 	struct cgroup_subsys_state css; | 
 |  | 
 | #ifdef CONFIG_FAIR_GROUP_SCHED | 
 | 	/* schedulable entities of this group on each cpu */ | 
 | 	struct sched_entity **se; | 
 | 	/* runqueue "owned" by this group on each cpu */ | 
 | 	struct cfs_rq **cfs_rq; | 
 | 	unsigned long shares; | 
 |  | 
 | 	atomic_t load_weight; | 
 | #endif | 
 |  | 
 | #ifdef CONFIG_RT_GROUP_SCHED | 
 | 	struct sched_rt_entity **rt_se; | 
 | 	struct rt_rq **rt_rq; | 
 |  | 
 | 	struct rt_bandwidth rt_bandwidth; | 
 | #endif | 
 |  | 
 | 	struct rcu_head rcu; | 
 | 	struct list_head list; | 
 |  | 
 | 	struct task_group *parent; | 
 | 	struct list_head siblings; | 
 | 	struct list_head children; | 
 |  | 
 | #ifdef CONFIG_SCHED_AUTOGROUP | 
 | 	struct autogroup *autogroup; | 
 | #endif | 
 |  | 
 | 	struct cfs_bandwidth cfs_bandwidth; | 
 | }; | 
 |  | 
 | #ifdef CONFIG_FAIR_GROUP_SCHED | 
 | #define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD | 
 |  | 
 | /* | 
 |  * 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	(1UL <<  1) | 
 | #define MAX_SHARES	(1UL << 18) | 
 | #endif | 
 |  | 
 | /* Default task group. | 
 |  *	Every task in system belong to this group at bootup. | 
 |  */ | 
 | extern struct task_group root_task_group; | 
 |  | 
 | typedef int (*tg_visitor)(struct task_group *, void *); | 
 |  | 
 | extern int walk_tg_tree_from(struct task_group *from, | 
 | 			     tg_visitor down, tg_visitor up, void *data); | 
 |  | 
 | /* | 
 |  * Iterate the full tree, calling @down when first entering a node and @up when | 
 |  * leaving it for the final time. | 
 |  * | 
 |  * Caller must hold rcu_lock or sufficient equivalent. | 
 |  */ | 
 | static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) | 
 | { | 
 | 	return walk_tg_tree_from(&root_task_group, down, up, data); | 
 | } | 
 |  | 
 | extern int tg_nop(struct task_group *tg, void *data); | 
 |  | 
 | extern void free_fair_sched_group(struct task_group *tg); | 
 | extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); | 
 | extern void unregister_fair_sched_group(struct task_group *tg, int cpu); | 
 | extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, | 
 | 			struct sched_entity *se, int cpu, | 
 | 			struct sched_entity *parent); | 
 | extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b); | 
 | extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); | 
 |  | 
 | extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); | 
 | extern void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); | 
 | extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); | 
 |  | 
 | extern void free_rt_sched_group(struct task_group *tg); | 
 | extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); | 
 | extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, | 
 | 		struct sched_rt_entity *rt_se, int cpu, | 
 | 		struct sched_rt_entity *parent); | 
 |  | 
 | #else /* CONFIG_CGROUP_SCHED */ | 
 |  | 
 | struct cfs_bandwidth { }; | 
 |  | 
 | #endif	/* CONFIG_CGROUP_SCHED */ | 
 |  | 
 | /* CFS-related fields in a runqueue */ | 
 | struct cfs_rq { | 
 | 	struct load_weight load; | 
 | 	unsigned long nr_running, h_nr_running; | 
 |  | 
 | 	u64 exec_clock; | 
 | 	u64 min_vruntime; | 
 | #ifndef CONFIG_64BIT | 
 | 	u64 min_vruntime_copy; | 
 | #endif | 
 |  | 
 | 	struct rb_root tasks_timeline; | 
 | 	struct rb_node *rb_leftmost; | 
 |  | 
 | 	/* | 
 | 	 * 'curr' points to currently running entity on this cfs_rq. | 
 | 	 * It is set to NULL otherwise (i.e when none are currently running). | 
 | 	 */ | 
 | 	struct sched_entity *curr, *next, *last, *skip; | 
 |  | 
 | #ifdef	CONFIG_SCHED_DEBUG | 
 | 	unsigned int nr_spread_over; | 
 | #endif | 
 |  | 
 | #ifdef CONFIG_FAIR_GROUP_SCHED | 
 | 	struct rq *rq;	/* cpu runqueue to which this cfs_rq is attached */ | 
 |  | 
 | 	/* | 
 | 	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in | 
 | 	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities | 
 | 	 * (like users, containers etc.) | 
 | 	 * | 
 | 	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This | 
 | 	 * list is used during load balance. | 
 | 	 */ | 
 | 	int on_list; | 
 | 	struct list_head leaf_cfs_rq_list; | 
 | 	struct task_group *tg;	/* group that "owns" this runqueue */ | 
 |  | 
 | #ifdef CONFIG_SMP | 
 | 	/* | 
 | 	 *   h_load = weight * f(tg) | 
 | 	 * | 
 | 	 * Where f(tg) is the recursive weight fraction assigned to | 
 | 	 * this group. | 
 | 	 */ | 
 | 	unsigned long h_load; | 
 |  | 
 | 	/* | 
 | 	 * Maintaining per-cpu shares distribution for group scheduling | 
 | 	 * | 
 | 	 * load_stamp is the last time we updated the load average | 
 | 	 * load_last is the last time we updated the load average and saw load | 
 | 	 * load_unacc_exec_time is currently unaccounted execution time | 
 | 	 */ | 
 | 	u64 load_avg; | 
 | 	u64 load_period; | 
 | 	u64 load_stamp, load_last, load_unacc_exec_time; | 
 |  | 
 | 	unsigned long load_contribution; | 
 | #endif /* CONFIG_SMP */ | 
 | #ifdef CONFIG_CFS_BANDWIDTH | 
 | 	int runtime_enabled; | 
 | 	u64 runtime_expires; | 
 | 	s64 runtime_remaining; | 
 |  | 
 | 	u64 throttled_timestamp; | 
 | 	int throttled, throttle_count; | 
 | 	struct list_head throttled_list; | 
 | #endif /* CONFIG_CFS_BANDWIDTH */ | 
 | #endif /* CONFIG_FAIR_GROUP_SCHED */ | 
 | }; | 
 |  | 
 | static inline int rt_bandwidth_enabled(void) | 
 | { | 
 | 	return sysctl_sched_rt_runtime >= 0; | 
 | } | 
 |  | 
 | /* Real-Time classes' related field in a runqueue: */ | 
 | struct rt_rq { | 
 | 	struct rt_prio_array active; | 
 | 	unsigned long rt_nr_running; | 
 | #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED | 
 | 	struct { | 
 | 		int curr; /* highest queued rt task prio */ | 
 | #ifdef CONFIG_SMP | 
 | 		int next; /* next highest */ | 
 | #endif | 
 | 	} highest_prio; | 
 | #endif | 
 | #ifdef CONFIG_SMP | 
 | 	unsigned long rt_nr_migratory; | 
 | 	unsigned long rt_nr_total; | 
 | 	int overloaded; | 
 | 	struct plist_head pushable_tasks; | 
 | #endif | 
 | 	int rt_throttled; | 
 | 	u64 rt_time; | 
 | 	u64 rt_runtime; | 
 | 	/* Nests inside the rq lock: */ | 
 | 	raw_spinlock_t rt_runtime_lock; | 
 |  | 
 | #ifdef CONFIG_RT_GROUP_SCHED | 
 | 	unsigned long rt_nr_boosted; | 
 |  | 
 | 	struct rq *rq; | 
 | 	struct list_head leaf_rt_rq_list; | 
 | 	struct task_group *tg; | 
 | #endif | 
 | }; | 
 |  | 
 | #ifdef CONFIG_SMP | 
 |  | 
 | /* | 
 |  * We add the notion of a root-domain which will be used to define per-domain | 
 |  * variables. Each exclusive cpuset essentially defines an island domain by | 
 |  * fully partitioning the member cpus from any other cpuset. Whenever a new | 
 |  * exclusive cpuset is created, we also create and attach a new root-domain | 
 |  * object. | 
 |  * | 
 |  */ | 
 | struct root_domain { | 
 | 	atomic_t refcount; | 
 | 	atomic_t rto_count; | 
 | 	struct rcu_head rcu; | 
 | 	cpumask_var_t span; | 
 | 	cpumask_var_t online; | 
 |  | 
 | 	/* | 
 | 	 * The "RT overload" flag: it gets set if a CPU has more than | 
 | 	 * one runnable RT task. | 
 | 	 */ | 
 | 	cpumask_var_t rto_mask; | 
 | 	struct cpupri cpupri; | 
 | }; | 
 |  | 
 | extern struct root_domain def_root_domain; | 
 |  | 
 | #endif /* CONFIG_SMP */ | 
 |  | 
 | /* | 
 |  * This is the main, per-CPU runqueue data structure. | 
 |  * | 
 |  * Locking rule: those places that want to lock multiple runqueues | 
 |  * (such as the load balancing or the thread migration code), lock | 
 |  * acquire operations must be ordered by ascending &runqueue. | 
 |  */ | 
 | struct rq { | 
 | 	/* runqueue lock: */ | 
 | 	raw_spinlock_t lock; | 
 |  | 
 | 	/* | 
 | 	 * nr_running and cpu_load should be in the same cacheline because | 
 | 	 * remote CPUs use both these fields when doing load calculation. | 
 | 	 */ | 
 | 	unsigned long nr_running; | 
 | 	#define CPU_LOAD_IDX_MAX 5 | 
 | 	unsigned long cpu_load[CPU_LOAD_IDX_MAX]; | 
 | 	unsigned long last_load_update_tick; | 
 | #ifdef CONFIG_NO_HZ | 
 | 	u64 nohz_stamp; | 
 | 	unsigned long nohz_flags; | 
 | #endif | 
 | 	int skip_clock_update; | 
 |  | 
 | 	/* capture load from *all* tasks on this cpu: */ | 
 | 	struct load_weight load; | 
 | 	unsigned long nr_load_updates; | 
 | 	u64 nr_switches; | 
 |  | 
 | 	struct cfs_rq cfs; | 
 | 	struct rt_rq rt; | 
 |  | 
 | #ifdef CONFIG_FAIR_GROUP_SCHED | 
 | 	/* list of leaf cfs_rq on this cpu: */ | 
 | 	struct list_head leaf_cfs_rq_list; | 
 | #endif | 
 | #ifdef CONFIG_RT_GROUP_SCHED | 
 | 	struct list_head leaf_rt_rq_list; | 
 | #endif | 
 |  | 
 | 	/* | 
 | 	 * This is part of a global counter where only the total sum | 
 | 	 * over all CPUs matters. A task can increase this counter on | 
 | 	 * one CPU and if it got migrated afterwards it may decrease | 
 | 	 * it on another CPU. Always updated under the runqueue lock: | 
 | 	 */ | 
 | 	unsigned long nr_uninterruptible; | 
 |  | 
 | 	struct task_struct *curr, *idle, *stop; | 
 | 	unsigned long next_balance; | 
 | 	struct mm_struct *prev_mm; | 
 |  | 
 | 	u64 clock; | 
 | 	u64 clock_task; | 
 |  | 
 | 	atomic_t nr_iowait; | 
 |  | 
 | #ifdef CONFIG_SMP | 
 | 	struct root_domain *rd; | 
 | 	struct sched_domain *sd; | 
 |  | 
 | 	unsigned long cpu_power; | 
 |  | 
 | 	unsigned char idle_balance; | 
 | 	/* For active balancing */ | 
 | 	int post_schedule; | 
 | 	int active_balance; | 
 | 	int push_cpu; | 
 | 	struct cpu_stop_work active_balance_work; | 
 | 	/* cpu of this runqueue: */ | 
 | 	int cpu; | 
 | 	int online; | 
 |  | 
 | 	struct list_head cfs_tasks; | 
 |  | 
 | 	u64 rt_avg; | 
 | 	u64 age_stamp; | 
 | 	u64 idle_stamp; | 
 | 	u64 avg_idle; | 
 | #endif | 
 |  | 
 | #ifdef CONFIG_IRQ_TIME_ACCOUNTING | 
 | 	u64 prev_irq_time; | 
 | #endif | 
 | #ifdef CONFIG_PARAVIRT | 
 | 	u64 prev_steal_time; | 
 | #endif | 
 | #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING | 
 | 	u64 prev_steal_time_rq; | 
 | #endif | 
 |  | 
 | 	/* calc_load related fields */ | 
 | 	unsigned long calc_load_update; | 
 | 	long calc_load_active; | 
 |  | 
 | #ifdef CONFIG_SCHED_HRTICK | 
 | #ifdef CONFIG_SMP | 
 | 	int hrtick_csd_pending; | 
 | 	struct call_single_data hrtick_csd; | 
 | #endif | 
 | 	struct hrtimer hrtick_timer; | 
 | #endif | 
 |  | 
 | #ifdef CONFIG_SCHEDSTATS | 
 | 	/* latency stats */ | 
 | 	struct sched_info rq_sched_info; | 
 | 	unsigned long long rq_cpu_time; | 
 | 	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ | 
 |  | 
 | 	/* sys_sched_yield() stats */ | 
 | 	unsigned int yld_count; | 
 |  | 
 | 	/* schedule() stats */ | 
 | 	unsigned int sched_count; | 
 | 	unsigned int sched_goidle; | 
 |  | 
 | 	/* try_to_wake_up() stats */ | 
 | 	unsigned int ttwu_count; | 
 | 	unsigned int ttwu_local; | 
 | #endif | 
 |  | 
 | #ifdef CONFIG_SMP | 
 | 	struct llist_head wake_list; | 
 | #endif | 
 | }; | 
 |  | 
 | static inline int cpu_of(struct rq *rq) | 
 | { | 
 | #ifdef CONFIG_SMP | 
 | 	return rq->cpu; | 
 | #else | 
 | 	return 0; | 
 | #endif | 
 | } | 
 |  | 
 | DECLARE_PER_CPU(struct rq, runqueues); | 
 |  | 
 | #ifdef CONFIG_STACK_SIZE | 
 | extern struct thread_info * current_kernel_thread; | 
 | #endif | 
 |  | 
 | #define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu))) | 
 | #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)) | 
 |  | 
 | #ifdef CONFIG_SMP | 
 |  | 
 | #define rcu_dereference_check_sched_domain(p) \ | 
 | 	rcu_dereference_check((p), \ | 
 | 			      lockdep_is_held(&sched_domains_mutex)) | 
 |  | 
 | /* | 
 |  * The domain tree (rq->sd) is protected by RCU's quiescent state transition. | 
 |  * See detach_destroy_domains: synchronize_sched for details. | 
 |  * | 
 |  * The domain tree of any CPU may only be accessed from within | 
 |  * preempt-disabled sections. | 
 |  */ | 
 | #define for_each_domain(cpu, __sd) \ | 
 | 	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \ | 
 | 			__sd; __sd = __sd->parent) | 
 |  | 
 | #define for_each_lower_domain(sd) for (; sd; sd = sd->child) | 
 |  | 
 | /** | 
 |  * highest_flag_domain - Return highest sched_domain containing flag. | 
 |  * @cpu:	The cpu whose highest level of sched domain is to | 
 |  *		be returned. | 
 |  * @flag:	The flag to check for the highest sched_domain | 
 |  *		for the given cpu. | 
 |  * | 
 |  * Returns the highest sched_domain of a cpu which contains the given flag. | 
 |  */ | 
 | static inline struct sched_domain *highest_flag_domain(int cpu, int flag) | 
 | { | 
 | 	struct sched_domain *sd, *hsd = NULL; | 
 |  | 
 | 	for_each_domain(cpu, sd) { | 
 | 		if (!(sd->flags & flag)) | 
 | 			break; | 
 | 		hsd = sd; | 
 | 	} | 
 |  | 
 | 	return hsd; | 
 | } | 
 |  | 
 | DECLARE_PER_CPU(struct sched_domain *, sd_llc); | 
 | DECLARE_PER_CPU(int, sd_llc_id); | 
 |  | 
 | #endif /* CONFIG_SMP */ | 
 |  | 
 | #include "stats.h" | 
 | #include "auto_group.h" | 
 |  | 
 | #ifdef CONFIG_CGROUP_SCHED | 
 |  | 
 | /* | 
 |  * Return the group to which this tasks belongs. | 
 |  * | 
 |  * We cannot use task_subsys_state() and friends because the cgroup | 
 |  * subsystem changes that value before the cgroup_subsys::attach() method | 
 |  * is called, therefore we cannot pin it and might observe the wrong value. | 
 |  * | 
 |  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup | 
 |  * core changes this before calling sched_move_task(). | 
 |  * | 
 |  * Instead we use a 'copy' which is updated from sched_move_task() while | 
 |  * holding both task_struct::pi_lock and rq::lock. | 
 |  */ | 
 | static inline struct task_group *task_group(struct task_struct *p) | 
 | { | 
 | 	return p->sched_task_group; | 
 | } | 
 |  | 
 | /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ | 
 | static inline void set_task_rq(struct task_struct *p, unsigned int cpu) | 
 | { | 
 | #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) | 
 | 	struct task_group *tg = task_group(p); | 
 | #endif | 
 |  | 
 | #ifdef CONFIG_FAIR_GROUP_SCHED | 
 | 	p->se.cfs_rq = tg->cfs_rq[cpu]; | 
 | 	p->se.parent = tg->se[cpu]; | 
 | #endif | 
 |  | 
 | #ifdef CONFIG_RT_GROUP_SCHED | 
 | 	p->rt.rt_rq  = tg->rt_rq[cpu]; | 
 | 	p->rt.parent = tg->rt_se[cpu]; | 
 | #endif | 
 | } | 
 |  | 
 | #else /* CONFIG_CGROUP_SCHED */ | 
 |  | 
 | static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } | 
 | static inline struct task_group *task_group(struct task_struct *p) | 
 | { | 
 | 	return NULL; | 
 | } | 
 |  | 
 | #endif /* CONFIG_CGROUP_SCHED */ | 
 |  | 
 | static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) | 
 | { | 
 | 	set_task_rq(p, cpu); | 
 | #ifdef CONFIG_SMP | 
 | 	/* | 
 | 	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be | 
 | 	 * successfuly executed on another CPU. We must ensure that updates of | 
 | 	 * per-task data have been completed by this moment. | 
 | 	 */ | 
 | 	smp_wmb(); | 
 | 	task_thread_info(p)->cpu = cpu; | 
 | #endif | 
 | } | 
 |  | 
 | /* | 
 |  * Tunables that become constants when CONFIG_SCHED_DEBUG is off: | 
 |  */ | 
 | #ifdef CONFIG_SCHED_DEBUG | 
 | # include <linux/static_key.h> | 
 | # define const_debug __read_mostly | 
 | #else | 
 | # define const_debug const | 
 | #endif | 
 |  | 
 | extern const_debug unsigned int sysctl_sched_features; | 
 |  | 
 | #define SCHED_FEAT(name, enabled)	\ | 
 | 	__SCHED_FEAT_##name , | 
 |  | 
 | enum { | 
 | #include "features.h" | 
 | 	__SCHED_FEAT_NR, | 
 | }; | 
 |  | 
 | #undef SCHED_FEAT | 
 |  | 
 | #if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL) | 
 | static __always_inline bool static_branch__true(struct static_key *key) | 
 | { | 
 | 	return static_key_true(key); /* Not out of line branch. */ | 
 | } | 
 |  | 
 | static __always_inline bool static_branch__false(struct static_key *key) | 
 | { | 
 | 	return static_key_false(key); /* Out of line branch. */ | 
 | } | 
 |  | 
 | #define SCHED_FEAT(name, enabled)					\ | 
 | static __always_inline bool static_branch_##name(struct static_key *key) \ | 
 | {									\ | 
 | 	return static_branch__##enabled(key);				\ | 
 | } | 
 |  | 
 | #include "features.h" | 
 |  | 
 | #undef SCHED_FEAT | 
 |  | 
 | extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; | 
 | #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) | 
 | #else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */ | 
 | #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) | 
 | #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */ | 
 |  | 
 | static inline u64 global_rt_period(void) | 
 | { | 
 | 	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; | 
 | } | 
 |  | 
 | static inline u64 global_rt_runtime(void) | 
 | { | 
 | 	if (sysctl_sched_rt_runtime < 0) | 
 | 		return RUNTIME_INF; | 
 |  | 
 | 	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; | 
 | } | 
 |  | 
 |  | 
 |  | 
 | static inline int task_current(struct rq *rq, struct task_struct *p) | 
 | { | 
 | 	return rq->curr == p; | 
 | } | 
 |  | 
 | static inline int task_running(struct rq *rq, struct task_struct *p) | 
 | { | 
 | #ifdef CONFIG_SMP | 
 | 	return p->on_cpu; | 
 | #else | 
 | 	return task_current(rq, p); | 
 | #endif | 
 | } | 
 |  | 
 |  | 
 | #ifndef prepare_arch_switch | 
 | # define prepare_arch_switch(next)	do { } while (0) | 
 | #endif | 
 | #ifndef finish_arch_switch | 
 | # define finish_arch_switch(prev)	do { } while (0) | 
 | #endif | 
 | #ifndef finish_arch_post_lock_switch | 
 | # define finish_arch_post_lock_switch()	do { } while (0) | 
 | #endif | 
 |  | 
 | #ifndef __ARCH_WANT_UNLOCKED_CTXSW | 
 | static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) | 
 | { | 
 | #ifdef CONFIG_SMP | 
 | 	/* | 
 | 	 * We can optimise this out completely for !SMP, because the | 
 | 	 * SMP rebalancing from interrupt is the only thing that cares | 
 | 	 * here. | 
 | 	 */ | 
 | 	next->on_cpu = 1; | 
 | #endif | 
 | } | 
 |  | 
 | static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) | 
 | { | 
 | #ifdef CONFIG_SMP | 
 | 	/* | 
 | 	 * After ->on_cpu is cleared, the task can be moved to a different CPU. | 
 | 	 * We must ensure this doesn't happen until the switch is completely | 
 | 	 * finished. | 
 | 	 */ | 
 | 	smp_wmb(); | 
 | 	prev->on_cpu = 0; | 
 | #endif | 
 | #ifdef CONFIG_DEBUG_SPINLOCK | 
 | 	/* this is a valid case when another task releases the spinlock */ | 
 | 	rq->lock.owner = current; | 
 | #endif | 
 | 	/* | 
 | 	 * If we are tracking spinlock dependencies then we have to | 
 | 	 * fix up the runqueue lock - which gets 'carried over' from | 
 | 	 * prev into current: | 
 | 	 */ | 
 | 	spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_); | 
 |  | 
 | 	raw_spin_unlock_irq(&rq->lock); | 
 | } | 
 |  | 
 | #else /* __ARCH_WANT_UNLOCKED_CTXSW */ | 
 | static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) | 
 | { | 
 | #ifdef CONFIG_SMP | 
 | 	/* | 
 | 	 * We can optimise this out completely for !SMP, because the | 
 | 	 * SMP rebalancing from interrupt is the only thing that cares | 
 | 	 * here. | 
 | 	 */ | 
 | 	next->on_cpu = 1; | 
 | #endif | 
 | #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW | 
 | 	raw_spin_unlock_irq(&rq->lock); | 
 | #else | 
 | 	raw_spin_unlock(&rq->lock); | 
 | #endif | 
 | } | 
 |  | 
 | static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) | 
 | { | 
 | #ifdef CONFIG_SMP | 
 | 	/* | 
 | 	 * After ->on_cpu is cleared, the task can be moved to a different CPU. | 
 | 	 * We must ensure this doesn't happen until the switch is completely | 
 | 	 * finished. | 
 | 	 */ | 
 | 	smp_wmb(); | 
 | 	prev->on_cpu = 0; | 
 | #endif | 
 | #ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW | 
 | 	local_irq_enable(); | 
 | #endif | 
 | } | 
 | #endif /* __ARCH_WANT_UNLOCKED_CTXSW */ | 
 |  | 
 |  | 
 | static inline void update_load_add(struct load_weight *lw, unsigned long inc) | 
 | { | 
 | 	lw->weight += inc; | 
 | 	lw->inv_weight = 0; | 
 | } | 
 |  | 
 | static inline void update_load_sub(struct load_weight *lw, unsigned long dec) | 
 | { | 
 | 	lw->weight -= dec; | 
 | 	lw->inv_weight = 0; | 
 | } | 
 |  | 
 | static inline void update_load_set(struct load_weight *lw, unsigned long w) | 
 | { | 
 | 	lw->weight = w; | 
 | 	lw->inv_weight = 0; | 
 | } | 
 |  | 
 | /* | 
 |  * To aid in avoiding the subversion of "niceness" due to uneven distribution | 
 |  * of tasks with abnormal "nice" values across CPUs the contribution that | 
 |  * each task makes to its run queue's load is weighted according to its | 
 |  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a | 
 |  * scaled version of the new time slice allocation that they receive on time | 
 |  * slice expiry etc. | 
 |  */ | 
 |  | 
 | #define WEIGHT_IDLEPRIO                3 | 
 | #define WMULT_IDLEPRIO         1431655765 | 
 |  | 
 | /* | 
 |  * Nice levels are multiplicative, with a gentle 10% change for every | 
 |  * nice level changed. I.e. when a CPU-bound task goes from nice 0 to | 
 |  * nice 1, it will get ~10% less CPU time than another CPU-bound task | 
 |  * that remained on nice 0. | 
 |  * | 
 |  * The "10% effect" is relative and cumulative: from _any_ nice level, | 
 |  * if you go up 1 level, it's -10% CPU usage, if you go down 1 level | 
 |  * it's +10% CPU usage. (to achieve that we use a multiplier of 1.25. | 
 |  * If a task goes up by ~10% and another task goes down by ~10% then | 
 |  * the relative distance between them is ~25%.) | 
 |  */ | 
 | static const int prio_to_weight[40] = { | 
 |  /* -20 */     88761,     71755,     56483,     46273,     36291, | 
 |  /* -15 */     29154,     23254,     18705,     14949,     11916, | 
 |  /* -10 */      9548,      7620,      6100,      4904,      3906, | 
 |  /*  -5 */      3121,      2501,      1991,      1586,      1277, | 
 |  /*   0 */      1024,       820,       655,       526,       423, | 
 |  /*   5 */       335,       272,       215,       172,       137, | 
 |  /*  10 */       110,        87,        70,        56,        45, | 
 |  /*  15 */        36,        29,        23,        18,        15, | 
 | }; | 
 |  | 
 | /* | 
 |  * Inverse (2^32/x) values of the prio_to_weight[] array, precalculated. | 
 |  * | 
 |  * In cases where the weight does not change often, we can use the | 
 |  * precalculated inverse to speed up arithmetics by turning divisions | 
 |  * into multiplications: | 
 |  */ | 
 | static const u32 prio_to_wmult[40] = { | 
 |  /* -20 */     48388,     59856,     76040,     92818,    118348, | 
 |  /* -15 */    147320,    184698,    229616,    287308,    360437, | 
 |  /* -10 */    449829,    563644,    704093,    875809,   1099582, | 
 |  /*  -5 */   1376151,   1717300,   2157191,   2708050,   3363326, | 
 |  /*   0 */   4194304,   5237765,   6557202,   8165337,  10153587, | 
 |  /*   5 */  12820798,  15790321,  19976592,  24970740,  31350126, | 
 |  /*  10 */  39045157,  49367440,  61356676,  76695844,  95443717, | 
 |  /*  15 */ 119304647, 148102320, 186737708, 238609294, 286331153, | 
 | }; | 
 |  | 
 | /* Time spent by the tasks of the cpu accounting group executing in ... */ | 
 | enum cpuacct_stat_index { | 
 | 	CPUACCT_STAT_USER,	/* ... user mode */ | 
 | 	CPUACCT_STAT_SYSTEM,	/* ... kernel mode */ | 
 |  | 
 | 	CPUACCT_STAT_NSTATS, | 
 | }; | 
 |  | 
 |  | 
 | #define sched_class_highest (&stop_sched_class) | 
 | #define for_each_class(class) \ | 
 |    for (class = sched_class_highest; class; class = class->next) | 
 |  | 
 | extern const struct sched_class stop_sched_class; | 
 | extern const struct sched_class rt_sched_class; | 
 | extern const struct sched_class fair_sched_class; | 
 | extern const struct sched_class idle_sched_class; | 
 |  | 
 |  | 
 | #ifdef CONFIG_SMP | 
 |  | 
 | extern void trigger_load_balance(struct rq *rq, int cpu); | 
 | extern void idle_balance(int this_cpu, struct rq *this_rq); | 
 |  | 
 | #else	/* CONFIG_SMP */ | 
 |  | 
 | static inline void idle_balance(int cpu, struct rq *rq) | 
 | { | 
 | } | 
 |  | 
 | #endif | 
 |  | 
 | extern void sysrq_sched_debug_show(void); | 
 | extern void sched_init_granularity(void); | 
 | extern void update_max_interval(void); | 
 | extern void update_group_power(struct sched_domain *sd, int cpu); | 
 | extern int update_runtime(struct notifier_block *nfb, unsigned long action, void *hcpu); | 
 | extern void init_sched_rt_class(void); | 
 | extern void init_sched_fair_class(void); | 
 |  | 
 | extern void resched_task(struct task_struct *p); | 
 | extern void resched_cpu(int cpu); | 
 |  | 
 | extern struct rt_bandwidth def_rt_bandwidth; | 
 | extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); | 
 |  | 
 | extern void update_idle_cpu_load(struct rq *this_rq); | 
 |  | 
 | #ifdef CONFIG_CGROUP_CPUACCT | 
 | #include <linux/cgroup.h> | 
 | /* track cpu usage of a group of tasks and its child groups */ | 
 | struct cpuacct { | 
 | 	struct cgroup_subsys_state css; | 
 | 	/* cpuusage holds pointer to a u64-type object on every cpu */ | 
 | 	u64 __percpu *cpuusage; | 
 | 	struct kernel_cpustat __percpu *cpustat; | 
 | }; | 
 |  | 
 | /* return cpu accounting group corresponding to this container */ | 
 | static inline struct cpuacct *cgroup_ca(struct cgroup *cgrp) | 
 | { | 
 | 	return container_of(cgroup_subsys_state(cgrp, cpuacct_subsys_id), | 
 | 			    struct cpuacct, css); | 
 | } | 
 |  | 
 | /* return cpu accounting group to which this task belongs */ | 
 | static inline struct cpuacct *task_ca(struct task_struct *tsk) | 
 | { | 
 | 	return container_of(task_subsys_state(tsk, cpuacct_subsys_id), | 
 | 			    struct cpuacct, css); | 
 | } | 
 |  | 
 | static inline struct cpuacct *parent_ca(struct cpuacct *ca) | 
 | { | 
 | 	if (!ca || !ca->css.cgroup->parent) | 
 | 		return NULL; | 
 | 	return cgroup_ca(ca->css.cgroup->parent); | 
 | } | 
 |  | 
 | extern void cpuacct_charge(struct task_struct *tsk, u64 cputime); | 
 | #else | 
 | static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {} | 
 | #endif | 
 |  | 
 | static inline void inc_nr_running(struct rq *rq) | 
 | { | 
 | 	rq->nr_running++; | 
 | } | 
 |  | 
 | static inline void dec_nr_running(struct rq *rq) | 
 | { | 
 | 	rq->nr_running--; | 
 | } | 
 |  | 
 | extern void update_rq_clock(struct rq *rq); | 
 |  | 
 | extern void activate_task(struct rq *rq, struct task_struct *p, int flags); | 
 | extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); | 
 |  | 
 | extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags); | 
 |  | 
 | extern const_debug unsigned int sysctl_sched_time_avg; | 
 | extern const_debug unsigned int sysctl_sched_nr_migrate; | 
 | extern const_debug unsigned int sysctl_sched_migration_cost; | 
 |  | 
 | static inline u64 sched_avg_period(void) | 
 | { | 
 | 	return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2; | 
 | } | 
 |  | 
 | #ifdef CONFIG_SCHED_HRTICK | 
 |  | 
 | /* | 
 |  * Use hrtick when: | 
 |  *  - enabled by features | 
 |  *  - hrtimer is actually high res | 
 |  */ | 
 | static inline int hrtick_enabled(struct rq *rq) | 
 | { | 
 | 	if (!sched_feat(HRTICK)) | 
 | 		return 0; | 
 | 	if (!cpu_active(cpu_of(rq))) | 
 | 		return 0; | 
 | 	return hrtimer_is_hres_active(&rq->hrtick_timer); | 
 | } | 
 |  | 
 | void hrtick_start(struct rq *rq, u64 delay); | 
 |  | 
 | #else | 
 |  | 
 | static inline int hrtick_enabled(struct rq *rq) | 
 | { | 
 | 	return 0; | 
 | } | 
 |  | 
 | #endif /* CONFIG_SCHED_HRTICK */ | 
 |  | 
 | #ifdef CONFIG_SMP | 
 | extern void sched_avg_update(struct rq *rq); | 
 | static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) | 
 | { | 
 | 	rq->rt_avg += rt_delta; | 
 | 	sched_avg_update(rq); | 
 | } | 
 | #else | 
 | static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { } | 
 | static inline void sched_avg_update(struct rq *rq) { } | 
 | #endif | 
 |  | 
 | extern void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period); | 
 |  | 
 | #ifdef CONFIG_SMP | 
 | #ifdef CONFIG_PREEMPT | 
 |  | 
 | static inline void double_rq_lock(struct rq *rq1, struct rq *rq2); | 
 |  | 
 | /* | 
 |  * fair double_lock_balance: Safely acquires both rq->locks in a fair | 
 |  * way at the expense of forcing extra atomic operations in all | 
 |  * invocations.  This assures that the double_lock is acquired using the | 
 |  * same underlying policy as the spinlock_t on this architecture, which | 
 |  * reduces latency compared to the unfair variant below.  However, it | 
 |  * also adds more overhead and therefore may reduce throughput. | 
 |  */ | 
 | static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) | 
 | 	__releases(this_rq->lock) | 
 | 	__acquires(busiest->lock) | 
 | 	__acquires(this_rq->lock) | 
 | { | 
 | 	raw_spin_unlock(&this_rq->lock); | 
 | 	double_rq_lock(this_rq, busiest); | 
 |  | 
 | 	return 1; | 
 | } | 
 |  | 
 | #else | 
 | /* | 
 |  * Unfair double_lock_balance: Optimizes throughput at the expense of | 
 |  * latency by eliminating extra atomic operations when the locks are | 
 |  * already in proper order on entry.  This favors lower cpu-ids and will | 
 |  * grant the double lock to lower cpus over higher ids under contention, | 
 |  * regardless of entry order into the function. | 
 |  */ | 
 | static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) | 
 | 	__releases(this_rq->lock) | 
 | 	__acquires(busiest->lock) | 
 | 	__acquires(this_rq->lock) | 
 | { | 
 | 	int ret = 0; | 
 |  | 
 | 	if (unlikely(!raw_spin_trylock(&busiest->lock))) { | 
 | 		if (busiest < this_rq) { | 
 | 			raw_spin_unlock(&this_rq->lock); | 
 | 			raw_spin_lock(&busiest->lock); | 
 | 			raw_spin_lock_nested(&this_rq->lock, | 
 | 					      SINGLE_DEPTH_NESTING); | 
 | 			ret = 1; | 
 | 		} else | 
 | 			raw_spin_lock_nested(&busiest->lock, | 
 | 					      SINGLE_DEPTH_NESTING); | 
 | 	} | 
 | 	return ret; | 
 | } | 
 |  | 
 | #endif /* CONFIG_PREEMPT */ | 
 |  | 
 | /* | 
 |  * double_lock_balance - lock the busiest runqueue, this_rq is locked already. | 
 |  */ | 
 | static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) | 
 | { | 
 | 	if (unlikely(!irqs_disabled())) { | 
 | 		/* printk() doesn't work good under rq->lock */ | 
 | 		raw_spin_unlock(&this_rq->lock); | 
 | 		BUG_ON(1); | 
 | 	} | 
 |  | 
 | 	return _double_lock_balance(this_rq, busiest); | 
 | } | 
 |  | 
 | static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) | 
 | 	__releases(busiest->lock) | 
 | { | 
 | 	raw_spin_unlock(&busiest->lock); | 
 | 	lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_); | 
 | } | 
 |  | 
 | /* | 
 |  * double_rq_lock - safely lock two runqueues | 
 |  * | 
 |  * Note this does not disable interrupts like task_rq_lock, | 
 |  * you need to do so manually before calling. | 
 |  */ | 
 | static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) | 
 | 	__acquires(rq1->lock) | 
 | 	__acquires(rq2->lock) | 
 | { | 
 | 	BUG_ON(!irqs_disabled()); | 
 | 	if (rq1 == rq2) { | 
 | 		raw_spin_lock(&rq1->lock); | 
 | 		__acquire(rq2->lock);	/* Fake it out ;) */ | 
 | 	} else { | 
 | 		if (rq1 < rq2) { | 
 | 			raw_spin_lock(&rq1->lock); | 
 | 			raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING); | 
 | 		} else { | 
 | 			raw_spin_lock(&rq2->lock); | 
 | 			raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING); | 
 | 		} | 
 | 	} | 
 | } | 
 |  | 
 | /* | 
 |  * double_rq_unlock - safely unlock two runqueues | 
 |  * | 
 |  * Note this does not restore interrupts like task_rq_unlock, | 
 |  * you need to do so manually after calling. | 
 |  */ | 
 | static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) | 
 | 	__releases(rq1->lock) | 
 | 	__releases(rq2->lock) | 
 | { | 
 | 	raw_spin_unlock(&rq1->lock); | 
 | 	if (rq1 != rq2) | 
 | 		raw_spin_unlock(&rq2->lock); | 
 | 	else | 
 | 		__release(rq2->lock); | 
 | } | 
 |  | 
 | #else /* CONFIG_SMP */ | 
 |  | 
 | /* | 
 |  * double_rq_lock - safely lock two runqueues | 
 |  * | 
 |  * Note this does not disable interrupts like task_rq_lock, | 
 |  * you need to do so manually before calling. | 
 |  */ | 
 | static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) | 
 | 	__acquires(rq1->lock) | 
 | 	__acquires(rq2->lock) | 
 | { | 
 | 	BUG_ON(!irqs_disabled()); | 
 | 	BUG_ON(rq1 != rq2); | 
 | 	raw_spin_lock(&rq1->lock); | 
 | 	__acquire(rq2->lock);	/* Fake it out ;) */ | 
 | } | 
 |  | 
 | /* | 
 |  * double_rq_unlock - safely unlock two runqueues | 
 |  * | 
 |  * Note this does not restore interrupts like task_rq_unlock, | 
 |  * you need to do so manually after calling. | 
 |  */ | 
 | static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) | 
 | 	__releases(rq1->lock) | 
 | 	__releases(rq2->lock) | 
 | { | 
 | 	BUG_ON(rq1 != rq2); | 
 | 	raw_spin_unlock(&rq1->lock); | 
 | 	__release(rq2->lock); | 
 | } | 
 |  | 
 | #endif | 
 |  | 
 | extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); | 
 | extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); | 
 | extern void print_cfs_stats(struct seq_file *m, int cpu); | 
 | extern void print_rt_stats(struct seq_file *m, int cpu); | 
 |  | 
 | extern void init_cfs_rq(struct cfs_rq *cfs_rq); | 
 | extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq); | 
 |  | 
 | extern void cfs_bandwidth_usage_inc(void); | 
 | extern void cfs_bandwidth_usage_dec(void); | 
 |  | 
 | #ifdef CONFIG_NO_HZ | 
 | enum rq_nohz_flag_bits { | 
 | 	NOHZ_TICK_STOPPED, | 
 | 	NOHZ_BALANCE_KICK, | 
 | 	NOHZ_IDLE, | 
 | }; | 
 |  | 
 | #define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags) | 
 | #endif |