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sched.h
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sched.h
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#include <linux/sched.h>
#include <linux/sched/autogroup.h>
#include <linux/sched/sysctl.h>
#include <linux/sched/topology.h>
#include <linux/sched/rt.h>
#include <linux/sched/deadline.h>
#include <linux/sched/clock.h>
#include <linux/sched/wake_q.h>
#include <linux/sched/signal.h>
#include <linux/sched/numa_balancing.h>
#include <linux/sched/mm.h>
#include <linux/sched/cpufreq.h>
#include <linux/sched/stat.h>
#include <linux/sched/nohz.h>
#include <linux/sched/debug.h>
#include <linux/sched/hotplug.h>
#include <linux/sched/task.h>
#include <linux/sched/task_stack.h>
#include <linux/sched/cputime.h>
#include <linux/sched/init.h>
#include <linux/u64_stats_sync.h>
#include <linux/kernel_stat.h>
#include <linux/binfmts.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/stop_machine.h>
#include <linux/irq_work.h>
#include <linux/tick.h>
#include <linux/slab.h>
#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#endif
#include "cpupri.h"
#include "cpudeadline.h"
#include "cpuacct.h"
#ifdef CONFIG_SCHED_DEBUG
# define SCHED_WARN_ON(x) WARN_ONCE(x, #x)
#else
# define SCHED_WARN_ON(x) ({ (void)(x), 0; })
#endif
struct rq;
struct cpuidle_state;
/* task_struct::on_rq states: */
#define TASK_ON_RQ_QUEUED 1
#define TASK_ON_RQ_MIGRATING 2
extern __read_mostly int scheduler_running;
extern unsigned long calc_load_update;
extern atomic_long_t calc_load_tasks;
extern void calc_global_load_tick(struct rq *this_rq);
extern long calc_load_fold_active(struct rq *this_rq, long adjust);
#ifdef CONFIG_SMP
extern void cpu_load_update_active(struct rq *this_rq);
#else
static inline void cpu_load_update_active(struct rq *this_rq) { }
#endif
/*
* Helpers for converting nanosecond timing to jiffy resolution
*/
#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
/*
* Increase resolution of nice-level calculations for 64-bit architectures.
* The extra resolution improves shares distribution and load balancing of
* low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
* hierarchies, especially on larger systems. This is not a user-visible change
* and does not change the user-interface for setting shares/weights.
*
* We increase resolution only if we have enough bits to allow this increased
* resolution (i.e. 64bit). The costs for increasing resolution when 32bit are
* pretty high and the returns do not justify the increased costs.
*
* Really only required when CONFIG_FAIR_GROUP_SCHED is also set, but to
* increase coverage and consistency always enable it on 64bit platforms.
*/
#ifdef CONFIG_64BIT
# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
# define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT)
# define scale_load_down(w) ((w) >> SCHED_FIXEDPOINT_SHIFT)
#else
# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
# define scale_load(w) (w)
# define scale_load_down(w) (w)
#endif
/*
* Task weight (visible to users) and its load (invisible to users) have
* independent resolution, but they should be well calibrated. We use
* scale_load() and scale_load_down(w) to convert between them. The
* following must be true:
*
* scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
*
*/
#define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
/*
* Single value that decides SCHED_DEADLINE internal math precision.
* 10 -> just above 1us
* 9 -> just above 0.5us
*/
#define DL_SCALE (10)
/*
* 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 idle_policy(int policy)
{
return policy == SCHED_IDLE;
}
static inline int fair_policy(int policy)
{
return policy == SCHED_NORMAL || policy == SCHED_BATCH;
}
static inline int rt_policy(int policy)
{
return policy == SCHED_FIFO || policy == SCHED_RR;
}
static inline int dl_policy(int policy)
{
return policy == SCHED_DEADLINE;
}
static inline bool valid_policy(int policy)
{
return idle_policy(policy) || fair_policy(policy) ||
rt_policy(policy) || dl_policy(policy);
}
static inline int task_has_rt_policy(struct task_struct *p)
{
return rt_policy(p->policy);
}
static inline int task_has_dl_policy(struct task_struct *p)
{
return dl_policy(p->policy);
}
/*
* Tells if entity @a should preempt entity @b.
*/
static inline bool
dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
{
return dl_time_before(a->deadline, b->deadline);
}
/*
* 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;
unsigned int rt_period_active;
};
void __dl_clear_params(struct task_struct *p);
/*
* To keep the bandwidth of -deadline tasks and groups under control
* we need some place where:
* - store the maximum -deadline bandwidth of the system (the group);
* - cache the fraction of that bandwidth that is currently allocated.
*
* This is all done in the data structure below. It is similar to the
* one used for RT-throttling (rt_bandwidth), with the main difference
* that, since here we are only interested in admission control, we
* do not decrease any runtime while the group "executes", neither we
* need a timer to replenish it.
*
* With respect to SMP, the bandwidth is given on a per-CPU basis,
* meaning that:
* - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
* - dl_total_bw array contains, in the i-eth element, the currently
* allocated bandwidth on the i-eth CPU.
* Moreover, groups consume bandwidth on each CPU, while tasks only
* consume bandwidth on the CPU they're running on.
* Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
* that will be shown the next time the proc or cgroup controls will
* be red. It on its turn can be changed by writing on its own
* control.
*/
struct dl_bandwidth {
raw_spinlock_t dl_runtime_lock;
u64 dl_runtime;
u64 dl_period;
};
static inline int dl_bandwidth_enabled(void)
{
return sysctl_sched_rt_runtime >= 0;
}
struct dl_bw {
raw_spinlock_t lock;
u64 bw, total_bw;
};
static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
static inline
void __dl_clear(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
{
dl_b->total_bw -= tsk_bw;
__dl_update(dl_b, (s32)tsk_bw / cpus);
}
static inline
void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
{
dl_b->total_bw += tsk_bw;
__dl_update(dl_b, -((s32)tsk_bw / cpus));
}
static inline
bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
{
return dl_b->bw != -1 &&
dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
}
void dl_change_utilization(struct task_struct *p, u64 new_bw);
extern void init_dl_bw(struct dl_bw *dl_b);
extern int sched_dl_global_validate(void);
extern void sched_dl_do_global(void);
extern int sched_dl_overflow(struct task_struct *p, int policy,
const struct sched_attr *attr);
extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
extern bool __checkparam_dl(const struct sched_attr *attr);
extern void __dl_clear_params(struct task_struct *p);
extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
extern int dl_task_can_attach(struct task_struct *p,
const struct cpumask *cs_cpus_allowed);
extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur,
const struct cpumask *trial);
extern bool dl_cpu_busy(unsigned int cpu);
#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 hierarchical_quota;
u64 runtime_expires;
int idle, period_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;
#ifdef CONFIG_SMP
/*
* load_avg can be heavily contended at clock tick time, so put
* it in its own cacheline separated from the fields above which
* will also be accessed at each tick.
*/
atomic_long_t load_avg ____cacheline_aligned;
#endif
#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
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 online_fair_sched_group(struct task_group *tg);
extern void unregister_fair_sched_group(struct task_group *tg);
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 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);
extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
extern long sched_group_rt_runtime(struct task_group *tg);
extern long sched_group_rt_period(struct task_group *tg);
extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
extern struct task_group *sched_create_group(struct task_group *parent);
extern void sched_online_group(struct task_group *tg,
struct task_group *parent);
extern void sched_destroy_group(struct task_group *tg);
extern void sched_offline_group(struct task_group *tg);
extern void sched_move_task(struct task_struct *tsk);
#ifdef CONFIG_FAIR_GROUP_SCHED
extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
#ifdef CONFIG_SMP
extern void set_task_rq_fair(struct sched_entity *se,
struct cfs_rq *prev, struct cfs_rq *next);
#else /* !CONFIG_SMP */
static inline void set_task_rq_fair(struct sched_entity *se,
struct cfs_rq *prev, struct cfs_rq *next) { }
#endif /* CONFIG_SMP */
#endif /* CONFIG_FAIR_GROUP_SCHED */
#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 int 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_SMP
/*
* CFS load tracking
*/
struct sched_avg avg;
u64 runnable_load_sum;
unsigned long runnable_load_avg;
#ifdef CONFIG_FAIR_GROUP_SCHED
unsigned long tg_load_avg_contrib;
unsigned long propagate_avg;
#endif
atomic_long_t removed_load_avg, removed_util_avg;
#ifndef CONFIG_64BIT
u64 load_last_update_time_copy;
#endif
#ifdef CONFIG_FAIR_GROUP_SCHED
/*
* h_load = weight * f(tg)
*
* Where f(tg) is the recursive weight fraction assigned to
* this group.
*/
unsigned long h_load;
u64 last_h_load_update;
struct sched_entity *h_load_next;
#endif /* CONFIG_FAIR_GROUP_SCHED */
#endif /* CONFIG_SMP */
#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_CFS_BANDWIDTH
int runtime_enabled;
u64 runtime_expires;
s64 runtime_remaining;
u64 throttled_clock, throttled_clock_task;
u64 throttled_clock_task_time;
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;
}
/* RT IPI pull logic requires IRQ_WORK */
#ifdef CONFIG_IRQ_WORK
# define HAVE_RT_PUSH_IPI
#endif
/* Real-Time classes' related field in a runqueue: */
struct rt_rq {
struct rt_prio_array active;
unsigned int rt_nr_running;
unsigned int rr_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;
#ifdef HAVE_RT_PUSH_IPI
int push_flags;
int push_cpu;
struct irq_work push_work;
raw_spinlock_t push_lock;
#endif
#endif /* CONFIG_SMP */
int rt_queued;
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 task_group *tg;
#endif
};
/* Deadline class' related fields in a runqueue */
struct dl_rq {
/* runqueue is an rbtree, ordered by deadline */
struct rb_root rb_root;
struct rb_node *rb_leftmost;
unsigned long dl_nr_running;
#ifdef CONFIG_SMP
/*
* Deadline values of the currently executing and the
* earliest ready task on this rq. Caching these facilitates
* the decision wether or not a ready but not running task
* should migrate somewhere else.
*/
struct {
u64 curr;
u64 next;
} earliest_dl;
unsigned long dl_nr_migratory;
int overloaded;
/*
* Tasks on this rq that can be pushed away. They are kept in
* an rb-tree, ordered by tasks' deadlines, with caching
* of the leftmost (earliest deadline) element.
*/
struct rb_root pushable_dl_tasks_root;
struct rb_node *pushable_dl_tasks_leftmost;
#else
struct dl_bw dl_bw;
#endif
/*
* "Active utilization" for this runqueue: increased when a
* task wakes up (becomes TASK_RUNNING) and decreased when a
* task blocks
*/
u64 running_bw;
/*
* Utilization of the tasks "assigned" to this runqueue (including
* the tasks that are in runqueue and the tasks that executed on this
* CPU and blocked). Increased when a task moves to this runqueue, and
* decreased when the task moves away (migrates, changes scheduling
* policy, or terminates).
* This is needed to compute the "inactive utilization" for the
* runqueue (inactive utilization = this_bw - running_bw).
*/
u64 this_bw;
u64 extra_bw;
/*
* Inverse of the fraction of CPU utilization that can be reclaimed
* by the GRUB algorithm.
*/
u64 bw_ratio;
};
#ifdef CONFIG_SMP
static inline bool sched_asym_prefer(int a, int b)
{
return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
}
/*
* 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;
/* Indicate more than one runnable task for any CPU */
bool overload;
/*
* The bit corresponding to a CPU gets set here if such CPU has more
* than one runnable -deadline task (as it is below for RT tasks).
*/
cpumask_var_t dlo_mask;
atomic_t dlo_count;
struct dl_bw dl_bw;
struct cpudl cpudl;
/*
* 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;
unsigned long max_cpu_capacity;
};
extern struct root_domain def_root_domain;
extern struct mutex sched_domains_mutex;
extern void init_defrootdomain(void);
extern int sched_init_domains(const struct cpumask *cpu_map);
extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
#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 int nr_running;
#ifdef CONFIG_NUMA_BALANCING
unsigned int nr_numa_running;
unsigned int nr_preferred_running;
#endif
#define CPU_LOAD_IDX_MAX 5
unsigned long cpu_load[CPU_LOAD_IDX_MAX];
#ifdef CONFIG_NO_HZ_COMMON
#ifdef CONFIG_SMP
unsigned long last_load_update_tick;
#endif /* CONFIG_SMP */
unsigned long nohz_flags;
#endif /* CONFIG_NO_HZ_COMMON */
#ifdef CONFIG_NO_HZ_FULL
unsigned long last_sched_tick;
#endif
/* 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;
struct dl_rq dl;
#ifdef CONFIG_FAIR_GROUP_SCHED
/* list of leaf cfs_rq on this cpu: */
struct list_head leaf_cfs_rq_list;
struct list_head *tmp_alone_branch;
#endif /* CONFIG_FAIR_GROUP_SCHED */
/*
* 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;
unsigned int clock_update_flags;
u64 clock;
u64 clock_task;
atomic_t nr_iowait;
#ifdef CONFIG_SMP
struct root_domain *rd;
struct sched_domain *sd;
unsigned long cpu_capacity;
unsigned long cpu_capacity_orig;
struct callback_head *balance_callback;
unsigned char idle_balance;
/* For active balancing */
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;
/* This is used to determine avg_idle's max value */
u64 max_idle_balance_cost;
#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
#ifdef CONFIG_CPU_IDLE
/* Must be inspected within a rcu lock section */
struct cpuidle_state *idle_state;
#endif
};
static inline int cpu_of(struct rq *rq)
{
#ifdef CONFIG_SMP
return rq->cpu;
#else
return 0;
#endif
}
#ifdef CONFIG_SCHED_SMT
extern struct static_key_false sched_smt_present;
extern void __update_idle_core(struct rq *rq);
static inline void update_idle_core(struct rq *rq)
{
if (static_branch_unlikely(&sched_smt_present))
__update_idle_core(rq);
}
#else
static inline void update_idle_core(struct rq *rq) { }
#endif
DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
#define this_rq() this_cpu_ptr(&runqueues)
#define task_rq(p) cpu_rq(task_cpu(p))
#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
#define raw_rq() raw_cpu_ptr(&runqueues)
static inline u64 __rq_clock_broken(struct rq *rq)
{
return READ_ONCE(rq->clock);
}
/*
* rq::clock_update_flags bits
*
* %RQCF_REQ_SKIP - will request skipping of clock update on the next
* call to __schedule(). This is an optimisation to avoid
* neighbouring rq clock updates.
*
* %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
* in effect and calls to update_rq_clock() are being ignored.
*
* %RQCF_UPDATED - is a debug flag that indicates whether a call has been
* made to update_rq_clock() since the last time rq::lock was pinned.
*
* If inside of __schedule(), clock_update_flags will have been
* shifted left (a left shift is a cheap operation for the fast path
* to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
*
* if (rq-clock_update_flags >= RQCF_UPDATED)
*
* to check if %RQCF_UPADTED is set. It'll never be shifted more than
* one position though, because the next rq_unpin_lock() will shift it
* back.
*/
#define RQCF_REQ_SKIP 0x01
#define RQCF_ACT_SKIP 0x02
#define RQCF_UPDATED 0x04
static inline void assert_clock_updated(struct rq *rq)
{
/*
* The only reason for not seeing a clock update since the
* last rq_pin_lock() is if we're currently skipping updates.
*/
SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
}
static inline u64 rq_clock(struct rq *rq)
{
lockdep_assert_held(&rq->lock);
assert_clock_updated(rq);
return rq->clock;
}
static inline u64 rq_clock_task(struct rq *rq)
{
lockdep_assert_held(&rq->lock);
assert_clock_updated(rq);
return rq->clock_task;
}
static inline void rq_clock_skip_update(struct rq *rq, bool skip)
{
lockdep_assert_held(&rq->lock);
if (skip)
rq->clock_update_flags |= RQCF_REQ_SKIP;
else
rq->clock_update_flags &= ~RQCF_REQ_SKIP;
}
struct rq_flags {
unsigned long flags;
struct pin_cookie cookie;
#ifdef CONFIG_SCHED_DEBUG
/*
* A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
* current pin context is stashed here in case it needs to be
* restored in rq_repin_lock().
*/
unsigned int clock_update_flags;
#endif
};
static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
{
rf->cookie = lockdep_pin_lock(&rq->lock);
#ifdef CONFIG_SCHED_DEBUG
rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
rf->clock_update_flags = 0;
#endif
}
static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
{
#ifdef CONFIG_SCHED_DEBUG
if (rq->clock_update_flags > RQCF_ACT_SKIP)
rf->clock_update_flags = RQCF_UPDATED;
#endif
lockdep_unpin_lock(&rq->lock, rf->cookie);
}
static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
{
lockdep_repin_lock(&rq->lock, rf->cookie);
#ifdef CONFIG_SCHED_DEBUG
/*
* Restore the value we stashed in @rf for this pin context.
*/
rq->clock_update_flags |= rf->clock_update_flags;
#endif
}
#ifdef CONFIG_NUMA
enum numa_topology_type {
NUMA_DIRECT,
NUMA_GLUELESS_MESH,
NUMA_BACKPLANE,
};
extern enum numa_topology_type sched_numa_topology_type;
extern int sched_max_numa_distance;
extern bool find_numa_distance(int distance);
#endif
#ifdef CONFIG_NUMA
extern void sched_init_numa(void);
extern void sched_domains_numa_masks_set(unsigned int cpu);
extern void sched_domains_numa_masks_clear(unsigned int cpu);
#else
static inline void sched_init_numa(void) { }
static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
#endif
#ifdef CONFIG_NUMA_BALANCING
/* The regions in numa_faults array from task_struct */
enum numa_faults_stats {
NUMA_MEM = 0,
NUMA_CPU,
NUMA_MEMBUF,
NUMA_CPUBUF
};
extern void sched_setnuma(struct task_struct *p, int node);
extern int migrate_task_to(struct task_struct *p, int cpu);
extern int migrate_swap(struct task_struct *, struct task_struct *);
#endif /* CONFIG_NUMA_BALANCING */
#ifdef CONFIG_SMP
static inline void
queue_balance_callback(struct rq *rq,
struct callback_head *head,
void (*func)(struct rq *rq))
{
lockdep_assert_held(&rq->lock);
if (unlikely(head->next))
return;
head->func = (void (*)(struct callback_head *))func;
head->next = rq->balance_callback;
rq->balance_callback = head;
}