1946 lines
50 KiB
C
1946 lines
50 KiB
C
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#include <linux/sched.h>
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#include <linux/sched/autogroup.h>
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#include <linux/sched/sysctl.h>
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#include <linux/sched/topology.h>
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#include <linux/sched/rt.h>
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#include <linux/sched/deadline.h>
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#include <linux/sched/clock.h>
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#include <linux/sched/wake_q.h>
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#include <linux/sched/signal.h>
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#include <linux/sched/numa_balancing.h>
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#include <linux/sched/mm.h>
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#include <linux/sched/cpufreq.h>
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#include <linux/sched/stat.h>
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#include <linux/sched/nohz.h>
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#include <linux/sched/debug.h>
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#include <linux/sched/hotplug.h>
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#include <linux/sched/task.h>
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#include <linux/sched/task_stack.h>
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#include <linux/sched/cputime.h>
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#include <linux/sched/init.h>
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#include <linux/u64_stats_sync.h>
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#include <linux/kernel_stat.h>
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#include <linux/binfmts.h>
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#include <linux/mutex.h>
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#include <linux/spinlock.h>
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#include <linux/stop_machine.h>
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#include <linux/irq_work.h>
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#include <linux/tick.h>
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#include <linux/slab.h>
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#ifdef CONFIG_PARAVIRT
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#include <asm/paravirt.h>
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#endif
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#include "cpupri.h"
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#include "cpudeadline.h"
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#include "cpuacct.h"
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#ifdef CONFIG_SCHED_DEBUG
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#define SCHED_WARN_ON(x) WARN_ONCE(x, #x)
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#else
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#define SCHED_WARN_ON(x) ((void)(x))
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#endif
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struct rq;
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struct cpuidle_state;
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/* task_struct::on_rq states: */
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#define TASK_ON_RQ_QUEUED 1
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#define TASK_ON_RQ_MIGRATING 2
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extern __read_mostly int scheduler_running;
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extern unsigned long calc_load_update;
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extern atomic_long_t calc_load_tasks;
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extern void calc_global_load_tick(struct rq *this_rq);
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extern long calc_load_fold_active(struct rq *this_rq, long adjust);
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#ifdef CONFIG_SMP
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extern void cpu_load_update_active(struct rq *this_rq);
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#else
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static inline void cpu_load_update_active(struct rq *this_rq) { }
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#endif
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/*
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* Helpers for converting nanosecond timing to jiffy resolution
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*/
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#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
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/*
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* Increase resolution of nice-level calculations for 64-bit architectures.
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* The extra resolution improves shares distribution and load balancing of
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* low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
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* hierarchies, especially on larger systems. This is not a user-visible change
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* and does not change the user-interface for setting shares/weights.
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*
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* We increase resolution only if we have enough bits to allow this increased
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* resolution (i.e. 64bit). The costs for increasing resolution when 32bit are
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* pretty high and the returns do not justify the increased costs.
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*
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* Really only required when CONFIG_FAIR_GROUP_SCHED is also set, but to
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* increase coverage and consistency always enable it on 64bit platforms.
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*/
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#ifdef CONFIG_64BIT
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# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
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# define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT)
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# define scale_load_down(w) ((w) >> SCHED_FIXEDPOINT_SHIFT)
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#else
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# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT)
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# define scale_load(w) (w)
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# define scale_load_down(w) (w)
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#endif
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/*
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* Task weight (visible to users) and its load (invisible to users) have
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* independent resolution, but they should be well calibrated. We use
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* scale_load() and scale_load_down(w) to convert between them. The
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* following must be true:
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*
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* scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
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*
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*/
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#define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT)
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/*
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* Single value that decides SCHED_DEADLINE internal math precision.
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* 10 -> just above 1us
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* 9 -> just above 0.5us
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*/
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#define DL_SCALE (10)
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/*
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* These are the 'tuning knobs' of the scheduler:
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*/
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/*
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* single value that denotes runtime == period, ie unlimited time.
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*/
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#define RUNTIME_INF ((u64)~0ULL)
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static inline int idle_policy(int policy)
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{
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return policy == SCHED_IDLE;
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}
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static inline int fair_policy(int policy)
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{
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return policy == SCHED_NORMAL || policy == SCHED_BATCH;
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}
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static inline int rt_policy(int policy)
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{
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return policy == SCHED_FIFO || policy == SCHED_RR;
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}
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static inline int dl_policy(int policy)
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{
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return policy == SCHED_DEADLINE;
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}
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static inline bool valid_policy(int policy)
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{
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return idle_policy(policy) || fair_policy(policy) ||
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rt_policy(policy) || dl_policy(policy);
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}
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static inline int task_has_rt_policy(struct task_struct *p)
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{
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return rt_policy(p->policy);
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}
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static inline int task_has_dl_policy(struct task_struct *p)
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{
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return dl_policy(p->policy);
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}
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/*
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* Tells if entity @a should preempt entity @b.
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*/
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static inline bool
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dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
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{
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return dl_time_before(a->deadline, b->deadline);
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}
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/*
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* This is the priority-queue data structure of the RT scheduling class:
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*/
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struct rt_prio_array {
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DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
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struct list_head queue[MAX_RT_PRIO];
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};
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struct rt_bandwidth {
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/* nests inside the rq lock: */
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raw_spinlock_t rt_runtime_lock;
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ktime_t rt_period;
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u64 rt_runtime;
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struct hrtimer rt_period_timer;
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unsigned int rt_period_active;
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};
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void __dl_clear_params(struct task_struct *p);
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/*
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* To keep the bandwidth of -deadline tasks and groups under control
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* we need some place where:
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* - store the maximum -deadline bandwidth of the system (the group);
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* - cache the fraction of that bandwidth that is currently allocated.
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*
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* This is all done in the data structure below. It is similar to the
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* one used for RT-throttling (rt_bandwidth), with the main difference
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* that, since here we are only interested in admission control, we
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* do not decrease any runtime while the group "executes", neither we
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* need a timer to replenish it.
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*
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* With respect to SMP, the bandwidth is given on a per-CPU basis,
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* meaning that:
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* - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
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* - dl_total_bw array contains, in the i-eth element, the currently
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* allocated bandwidth on the i-eth CPU.
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* Moreover, groups consume bandwidth on each CPU, while tasks only
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* consume bandwidth on the CPU they're running on.
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* Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
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* that will be shown the next time the proc or cgroup controls will
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* be red. It on its turn can be changed by writing on its own
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* control.
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*/
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struct dl_bandwidth {
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raw_spinlock_t dl_runtime_lock;
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u64 dl_runtime;
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u64 dl_period;
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};
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static inline int dl_bandwidth_enabled(void)
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{
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return sysctl_sched_rt_runtime >= 0;
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}
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extern struct dl_bw *dl_bw_of(int i);
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struct dl_bw {
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raw_spinlock_t lock;
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u64 bw, total_bw;
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};
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static inline
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void __dl_clear(struct dl_bw *dl_b, u64 tsk_bw)
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{
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dl_b->total_bw -= tsk_bw;
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}
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static inline
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void __dl_add(struct dl_bw *dl_b, u64 tsk_bw)
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{
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dl_b->total_bw += tsk_bw;
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}
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static inline
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bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
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{
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return dl_b->bw != -1 &&
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dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
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}
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extern void init_dl_bw(struct dl_bw *dl_b);
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#ifdef CONFIG_CGROUP_SCHED
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#include <linux/cgroup.h>
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struct cfs_rq;
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struct rt_rq;
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extern struct list_head task_groups;
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struct cfs_bandwidth {
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#ifdef CONFIG_CFS_BANDWIDTH
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raw_spinlock_t lock;
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ktime_t period;
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u64 quota, runtime;
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s64 hierarchical_quota;
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u64 runtime_expires;
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int idle, period_active;
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struct hrtimer period_timer, slack_timer;
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struct list_head throttled_cfs_rq;
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/* statistics */
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int nr_periods, nr_throttled;
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u64 throttled_time;
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#endif
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};
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/* task group related information */
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struct task_group {
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struct cgroup_subsys_state css;
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#ifdef CONFIG_FAIR_GROUP_SCHED
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/* schedulable entities of this group on each cpu */
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struct sched_entity **se;
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/* runqueue "owned" by this group on each cpu */
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struct cfs_rq **cfs_rq;
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unsigned long shares;
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#ifdef CONFIG_SMP
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/*
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* load_avg can be heavily contended at clock tick time, so put
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* it in its own cacheline separated from the fields above which
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* will also be accessed at each tick.
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*/
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atomic_long_t load_avg ____cacheline_aligned;
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#endif
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#endif
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#ifdef CONFIG_RT_GROUP_SCHED
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struct sched_rt_entity **rt_se;
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struct rt_rq **rt_rq;
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struct rt_bandwidth rt_bandwidth;
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#endif
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struct rcu_head rcu;
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struct list_head list;
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struct task_group *parent;
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struct list_head siblings;
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struct list_head children;
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#ifdef CONFIG_SCHED_AUTOGROUP
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struct autogroup *autogroup;
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#endif
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struct cfs_bandwidth cfs_bandwidth;
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};
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#ifdef CONFIG_FAIR_GROUP_SCHED
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#define ROOT_TASK_GROUP_LOAD NICE_0_LOAD
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/*
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* A weight of 0 or 1 can cause arithmetics problems.
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* A weight of a cfs_rq is the sum of weights of which entities
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* are queued on this cfs_rq, so a weight of a entity should not be
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* too large, so as the shares value of a task group.
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* (The default weight is 1024 - so there's no practical
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* limitation from this.)
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*/
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#define MIN_SHARES (1UL << 1)
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#define MAX_SHARES (1UL << 18)
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#endif
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typedef int (*tg_visitor)(struct task_group *, void *);
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extern int walk_tg_tree_from(struct task_group *from,
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tg_visitor down, tg_visitor up, void *data);
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/*
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* Iterate the full tree, calling @down when first entering a node and @up when
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* leaving it for the final time.
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*
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* Caller must hold rcu_lock or sufficient equivalent.
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*/
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static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
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{
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return walk_tg_tree_from(&root_task_group, down, up, data);
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}
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extern int tg_nop(struct task_group *tg, void *data);
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extern void free_fair_sched_group(struct task_group *tg);
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extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
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extern void online_fair_sched_group(struct task_group *tg);
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extern void unregister_fair_sched_group(struct task_group *tg);
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extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
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struct sched_entity *se, int cpu,
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struct sched_entity *parent);
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extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
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extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
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extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
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extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
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extern void free_rt_sched_group(struct task_group *tg);
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extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
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extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
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struct sched_rt_entity *rt_se, int cpu,
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struct sched_rt_entity *parent);
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extern struct task_group *sched_create_group(struct task_group *parent);
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extern void sched_online_group(struct task_group *tg,
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struct task_group *parent);
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extern void sched_destroy_group(struct task_group *tg);
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extern void sched_offline_group(struct task_group *tg);
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extern void sched_move_task(struct task_struct *tsk);
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#ifdef CONFIG_FAIR_GROUP_SCHED
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extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
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#ifdef CONFIG_SMP
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extern void set_task_rq_fair(struct sched_entity *se,
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struct cfs_rq *prev, struct cfs_rq *next);
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#else /* !CONFIG_SMP */
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static inline void set_task_rq_fair(struct sched_entity *se,
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struct cfs_rq *prev, struct cfs_rq *next) { }
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#endif /* CONFIG_SMP */
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#endif /* CONFIG_FAIR_GROUP_SCHED */
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#else /* CONFIG_CGROUP_SCHED */
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struct cfs_bandwidth { };
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#endif /* CONFIG_CGROUP_SCHED */
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/* CFS-related fields in a runqueue */
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struct cfs_rq {
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struct load_weight load;
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unsigned int nr_running, h_nr_running;
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u64 exec_clock;
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u64 min_vruntime;
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#ifndef CONFIG_64BIT
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u64 min_vruntime_copy;
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#endif
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struct rb_root tasks_timeline;
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struct rb_node *rb_leftmost;
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/*
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* 'curr' points to currently running entity on this cfs_rq.
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* It is set to NULL otherwise (i.e when none are currently running).
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*/
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struct sched_entity *curr, *next, *last, *skip;
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#ifdef CONFIG_SCHED_DEBUG
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unsigned int nr_spread_over;
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#endif
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#ifdef CONFIG_SMP
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/*
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* CFS load tracking
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*/
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struct sched_avg avg;
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u64 runnable_load_sum;
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unsigned long runnable_load_avg;
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#ifdef CONFIG_FAIR_GROUP_SCHED
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unsigned long tg_load_avg_contrib;
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unsigned long propagate_avg;
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#endif
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atomic_long_t removed_load_avg, removed_util_avg;
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#ifndef CONFIG_64BIT
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u64 load_last_update_time_copy;
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#endif
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#ifdef CONFIG_FAIR_GROUP_SCHED
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/*
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* h_load = weight * f(tg)
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*
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* Where f(tg) is the recursive weight fraction assigned to
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* this group.
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*/
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unsigned long h_load;
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u64 last_h_load_update;
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struct sched_entity *h_load_next;
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#endif /* CONFIG_FAIR_GROUP_SCHED */
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#endif /* CONFIG_SMP */
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#ifdef CONFIG_FAIR_GROUP_SCHED
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struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */
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/*
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* leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
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* a hierarchy). Non-leaf lrqs hold other higher schedulable entities
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* (like users, containers etc.)
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*
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* leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
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* list is used during load balance.
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*/
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int on_list;
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struct list_head leaf_cfs_rq_list;
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struct task_group *tg; /* group that "owns" this runqueue */
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#ifdef CONFIG_CFS_BANDWIDTH
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int runtime_enabled;
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u64 runtime_expires;
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s64 runtime_remaining;
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u64 throttled_clock, throttled_clock_task;
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u64 throttled_clock_task_time;
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int throttled, throttle_count;
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struct list_head throttled_list;
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#endif /* CONFIG_CFS_BANDWIDTH */
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#endif /* CONFIG_FAIR_GROUP_SCHED */
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};
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static inline int rt_bandwidth_enabled(void)
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{
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return sysctl_sched_rt_runtime >= 0;
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}
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/* RT IPI pull logic requires IRQ_WORK */
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#ifdef CONFIG_IRQ_WORK
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# define HAVE_RT_PUSH_IPI
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#endif
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/* Real-Time classes' related field in a runqueue: */
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struct rt_rq {
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struct rt_prio_array active;
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unsigned int rt_nr_running;
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unsigned int rr_nr_running;
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#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
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struct {
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int curr; /* highest queued rt task prio */
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#ifdef CONFIG_SMP
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int next; /* next highest */
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#endif
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} highest_prio;
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#endif
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#ifdef CONFIG_SMP
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unsigned long rt_nr_migratory;
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unsigned long rt_nr_total;
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int overloaded;
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struct plist_head pushable_tasks;
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#ifdef HAVE_RT_PUSH_IPI
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int push_flags;
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int push_cpu;
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struct irq_work push_work;
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raw_spinlock_t push_lock;
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#endif
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#endif /* CONFIG_SMP */
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int rt_queued;
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int rt_throttled;
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u64 rt_time;
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u64 rt_runtime;
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|
/* 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
|
|
};
|
|
|
|
#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 cpumask_var_t fallback_doms;
|
|
extern cpumask_var_t sched_domains_tmpmask;
|
|
|
|
extern void init_defrootdomain(void);
|
|
extern int init_sched_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;
|
|
}
|
|
|
|
extern void sched_ttwu_pending(void);
|
|
|
|
#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;
|
|
}
|
|
|
|
static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
|
|
{
|
|
struct sched_domain *sd;
|
|
|
|
for_each_domain(cpu, sd) {
|
|
if (sd->flags & flag)
|
|
break;
|
|
}
|
|
|
|
return sd;
|
|
}
|
|
|
|
DECLARE_PER_CPU(struct sched_domain *, sd_llc);
|
|
DECLARE_PER_CPU(int, sd_llc_size);
|
|
DECLARE_PER_CPU(int, sd_llc_id);
|
|
DECLARE_PER_CPU(struct sched_domain_shared *, sd_llc_shared);
|
|
DECLARE_PER_CPU(struct sched_domain *, sd_numa);
|
|
DECLARE_PER_CPU(struct sched_domain *, sd_asym);
|
|
|
|
struct sched_group_capacity {
|
|
atomic_t ref;
|
|
/*
|
|
* CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
|
|
* for a single CPU.
|
|
*/
|
|
unsigned long capacity;
|
|
unsigned long min_capacity; /* Min per-CPU capacity in group */
|
|
unsigned long next_update;
|
|
int imbalance; /* XXX unrelated to capacity but shared group state */
|
|
|
|
unsigned long cpumask[0]; /* iteration mask */
|
|
};
|
|
|
|
struct sched_group {
|
|
struct sched_group *next; /* Must be a circular list */
|
|
atomic_t ref;
|
|
|
|
unsigned int group_weight;
|
|
struct sched_group_capacity *sgc;
|
|
int asym_prefer_cpu; /* cpu of highest priority in group */
|
|
|
|
/*
|
|
* The CPUs this group covers.
|
|
*
|
|
* NOTE: this field is variable length. (Allocated dynamically
|
|
* by attaching extra space to the end of the structure,
|
|
* depending on how many CPUs the kernel has booted up with)
|
|
*/
|
|
unsigned long cpumask[0];
|
|
};
|
|
|
|
static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
|
|
{
|
|
return to_cpumask(sg->cpumask);
|
|
}
|
|
|
|
/*
|
|
* cpumask masking which cpus in the group are allowed to iterate up the domain
|
|
* tree.
|
|
*/
|
|
static inline struct cpumask *sched_group_mask(struct sched_group *sg)
|
|
{
|
|
return to_cpumask(sg->sgc->cpumask);
|
|
}
|
|
|
|
/**
|
|
* group_first_cpu - Returns the first cpu in the cpumask of a sched_group.
|
|
* @group: The group whose first cpu is to be returned.
|
|
*/
|
|
static inline unsigned int group_first_cpu(struct sched_group *group)
|
|
{
|
|
return cpumask_first(sched_group_cpus(group));
|
|
}
|
|
|
|
extern int group_balance_cpu(struct sched_group *sg);
|
|
|
|
#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
|
|
void register_sched_domain_sysctl(void);
|
|
void unregister_sched_domain_sysctl(void);
|
|
#else
|
|
static inline void register_sched_domain_sysctl(void)
|
|
{
|
|
}
|
|
static inline void unregister_sched_domain_sysctl(void)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
#else
|
|
|
|
static inline void sched_ttwu_pending(void) { }
|
|
|
|
#endif /* CONFIG_SMP */
|
|
|
|
#include "stats.h"
|
|
#include "autogroup.h"
|
|
|
|
#ifdef CONFIG_CGROUP_SCHED
|
|
|
|
/*
|
|
* Return the group to which this tasks belongs.
|
|
*
|
|
* We cannot use task_css() 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
|
|
set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
|
|
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();
|
|
#ifdef CONFIG_THREAD_INFO_IN_TASK
|
|
p->cpu = cpu;
|
|
#else
|
|
task_thread_info(p)->cpu = cpu;
|
|
#endif
|
|
p->wake_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)
|
|
#define SCHED_FEAT(name, enabled) \
|
|
static __always_inline bool static_branch_##name(struct static_key *key) \
|
|
{ \
|
|
return static_key_##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 */
|
|
|
|
extern struct static_key_false sched_numa_balancing;
|
|
extern struct static_key_false sched_schedstats;
|
|
|
|
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
|
|
}
|
|
|
|
static inline int task_on_rq_queued(struct task_struct *p)
|
|
{
|
|
return p->on_rq == TASK_ON_RQ_QUEUED;
|
|
}
|
|
|
|
static inline int task_on_rq_migrating(struct task_struct *p)
|
|
{
|
|
return p->on_rq == TASK_ON_RQ_MIGRATING;
|
|
}
|
|
|
|
#ifndef prepare_arch_switch
|
|
# define prepare_arch_switch(next) do { } while (0)
|
|
#endif
|
|
#ifndef finish_arch_post_lock_switch
|
|
# define finish_arch_post_lock_switch() do { } while (0)
|
|
#endif
|
|
|
|
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.
|
|
*
|
|
* In particular, the load of prev->state in finish_task_switch() must
|
|
* happen before this.
|
|
*
|
|
* Pairs with the smp_cond_load_acquire() in try_to_wake_up().
|
|
*/
|
|
smp_store_release(&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);
|
|
}
|
|
|
|
/*
|
|
* wake flags
|
|
*/
|
|
#define WF_SYNC 0x01 /* waker goes to sleep after wakeup */
|
|
#define WF_FORK 0x02 /* child wakeup after fork */
|
|
#define WF_MIGRATED 0x4 /* internal use, task got migrated */
|
|
|
|
/*
|
|
* 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
|
|
|
|
extern const int sched_prio_to_weight[40];
|
|
extern const u32 sched_prio_to_wmult[40];
|
|
|
|
/*
|
|
* {de,en}queue flags:
|
|
*
|
|
* DEQUEUE_SLEEP - task is no longer runnable
|
|
* ENQUEUE_WAKEUP - task just became runnable
|
|
*
|
|
* SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
|
|
* are in a known state which allows modification. Such pairs
|
|
* should preserve as much state as possible.
|
|
*
|
|
* MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
|
|
* in the runqueue.
|
|
*
|
|
* ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
|
|
* ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
|
|
* ENQUEUE_MIGRATED - the task was migrated during wakeup
|
|
*
|
|
*/
|
|
|
|
#define DEQUEUE_SLEEP 0x01
|
|
#define DEQUEUE_SAVE 0x02 /* matches ENQUEUE_RESTORE */
|
|
#define DEQUEUE_MOVE 0x04 /* matches ENQUEUE_MOVE */
|
|
|
|
#define ENQUEUE_WAKEUP 0x01
|
|
#define ENQUEUE_RESTORE 0x02
|
|
#define ENQUEUE_MOVE 0x04
|
|
|
|
#define ENQUEUE_HEAD 0x08
|
|
#define ENQUEUE_REPLENISH 0x10
|
|
#ifdef CONFIG_SMP
|
|
#define ENQUEUE_MIGRATED 0x20
|
|
#else
|
|
#define ENQUEUE_MIGRATED 0x00
|
|
#endif
|
|
|
|
#define RETRY_TASK ((void *)-1UL)
|
|
|
|
struct sched_class {
|
|
const struct sched_class *next;
|
|
|
|
void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
|
|
void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
|
|
void (*yield_task) (struct rq *rq);
|
|
bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt);
|
|
|
|
void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
|
|
|
|
/*
|
|
* It is the responsibility of the pick_next_task() method that will
|
|
* return the next task to call put_prev_task() on the @prev task or
|
|
* something equivalent.
|
|
*
|
|
* May return RETRY_TASK when it finds a higher prio class has runnable
|
|
* tasks.
|
|
*/
|
|
struct task_struct * (*pick_next_task) (struct rq *rq,
|
|
struct task_struct *prev,
|
|
struct rq_flags *rf);
|
|
void (*put_prev_task) (struct rq *rq, struct task_struct *p);
|
|
|
|
#ifdef CONFIG_SMP
|
|
int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
|
|
void (*migrate_task_rq)(struct task_struct *p);
|
|
|
|
void (*task_woken) (struct rq *this_rq, struct task_struct *task);
|
|
|
|
void (*set_cpus_allowed)(struct task_struct *p,
|
|
const struct cpumask *newmask);
|
|
|
|
void (*rq_online)(struct rq *rq);
|
|
void (*rq_offline)(struct rq *rq);
|
|
#endif
|
|
|
|
void (*set_curr_task) (struct rq *rq);
|
|
void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
|
|
void (*task_fork) (struct task_struct *p);
|
|
void (*task_dead) (struct task_struct *p);
|
|
|
|
/*
|
|
* The switched_from() call is allowed to drop rq->lock, therefore we
|
|
* cannot assume the switched_from/switched_to pair is serliazed by
|
|
* rq->lock. They are however serialized by p->pi_lock.
|
|
*/
|
|
void (*switched_from) (struct rq *this_rq, struct task_struct *task);
|
|
void (*switched_to) (struct rq *this_rq, struct task_struct *task);
|
|
void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
|
|
int oldprio);
|
|
|
|
unsigned int (*get_rr_interval) (struct rq *rq,
|
|
struct task_struct *task);
|
|
|
|
void (*update_curr) (struct rq *rq);
|
|
|
|
#define TASK_SET_GROUP 0
|
|
#define TASK_MOVE_GROUP 1
|
|
|
|
#ifdef CONFIG_FAIR_GROUP_SCHED
|
|
void (*task_change_group) (struct task_struct *p, int type);
|
|
#endif
|
|
};
|
|
|
|
static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
|
|
{
|
|
prev->sched_class->put_prev_task(rq, prev);
|
|
}
|
|
|
|
static inline void set_curr_task(struct rq *rq, struct task_struct *curr)
|
|
{
|
|
curr->sched_class->set_curr_task(rq);
|
|
}
|
|
|
|
#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 dl_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 update_group_capacity(struct sched_domain *sd, int cpu);
|
|
|
|
extern void trigger_load_balance(struct rq *rq);
|
|
|
|
extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
|
|
|
|
#endif
|
|
|
|
#ifdef CONFIG_CPU_IDLE
|
|
static inline void idle_set_state(struct rq *rq,
|
|
struct cpuidle_state *idle_state)
|
|
{
|
|
rq->idle_state = idle_state;
|
|
}
|
|
|
|
static inline struct cpuidle_state *idle_get_state(struct rq *rq)
|
|
{
|
|
SCHED_WARN_ON(!rcu_read_lock_held());
|
|
return rq->idle_state;
|
|
}
|
|
#else
|
|
static inline void idle_set_state(struct rq *rq,
|
|
struct cpuidle_state *idle_state)
|
|
{
|
|
}
|
|
|
|
static inline struct cpuidle_state *idle_get_state(struct rq *rq)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
extern void sysrq_sched_debug_show(void);
|
|
extern void sched_init_granularity(void);
|
|
extern void update_max_interval(void);
|
|
|
|
extern void init_sched_dl_class(void);
|
|
extern void init_sched_rt_class(void);
|
|
extern void init_sched_fair_class(void);
|
|
|
|
extern void resched_curr(struct rq *rq);
|
|
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 struct dl_bandwidth def_dl_bandwidth;
|
|
extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
|
|
extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
|
|
|
|
unsigned long to_ratio(u64 period, u64 runtime);
|
|
|
|
extern void init_entity_runnable_average(struct sched_entity *se);
|
|
extern void post_init_entity_util_avg(struct sched_entity *se);
|
|
|
|
#ifdef CONFIG_NO_HZ_FULL
|
|
extern bool sched_can_stop_tick(struct rq *rq);
|
|
|
|
/*
|
|
* Tick may be needed by tasks in the runqueue depending on their policy and
|
|
* requirements. If tick is needed, lets send the target an IPI to kick it out of
|
|
* nohz mode if necessary.
|
|
*/
|
|
static inline void sched_update_tick_dependency(struct rq *rq)
|
|
{
|
|
int cpu;
|
|
|
|
if (!tick_nohz_full_enabled())
|
|
return;
|
|
|
|
cpu = cpu_of(rq);
|
|
|
|
if (!tick_nohz_full_cpu(cpu))
|
|
return;
|
|
|
|
if (sched_can_stop_tick(rq))
|
|
tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
|
|
else
|
|
tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
|
|
}
|
|
#else
|
|
static inline void sched_update_tick_dependency(struct rq *rq) { }
|
|
#endif
|
|
|
|
static inline void add_nr_running(struct rq *rq, unsigned count)
|
|
{
|
|
unsigned prev_nr = rq->nr_running;
|
|
|
|
rq->nr_running = prev_nr + count;
|
|
|
|
if (prev_nr < 2 && rq->nr_running >= 2) {
|
|
#ifdef CONFIG_SMP
|
|
if (!rq->rd->overload)
|
|
rq->rd->overload = true;
|
|
#endif
|
|
}
|
|
|
|
sched_update_tick_dependency(rq);
|
|
}
|
|
|
|
static inline void sub_nr_running(struct rq *rq, unsigned count)
|
|
{
|
|
rq->nr_running -= count;
|
|
/* Check if we still need preemption */
|
|
sched_update_tick_dependency(rq);
|
|
}
|
|
|
|
static inline void rq_last_tick_reset(struct rq *rq)
|
|
{
|
|
#ifdef CONFIG_NO_HZ_FULL
|
|
rq->last_sched_tick = jiffies;
|
|
#endif
|
|
}
|
|
|
|
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);
|
|
|
|
#ifndef arch_scale_freq_capacity
|
|
static __always_inline
|
|
unsigned long arch_scale_freq_capacity(struct sched_domain *sd, int cpu)
|
|
{
|
|
return SCHED_CAPACITY_SCALE;
|
|
}
|
|
#endif
|
|
|
|
#ifndef arch_scale_cpu_capacity
|
|
static __always_inline
|
|
unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
|
|
{
|
|
if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1))
|
|
return sd->smt_gain / sd->span_weight;
|
|
|
|
return SCHED_CAPACITY_SCALE;
|
|
}
|
|
#endif
|
|
|
|
static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
|
|
{
|
|
rq->rt_avg += rt_delta * arch_scale_freq_capacity(NULL, cpu_of(rq));
|
|
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
|
|
|
|
struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
|
|
__acquires(rq->lock);
|
|
struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
|
|
__acquires(p->pi_lock)
|
|
__acquires(rq->lock);
|
|
|
|
static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
|
|
__releases(rq->lock)
|
|
{
|
|
rq_unpin_lock(rq, rf);
|
|
raw_spin_unlock(&rq->lock);
|
|
}
|
|
|
|
static inline void
|
|
task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
|
|
__releases(rq->lock)
|
|
__releases(p->pi_lock)
|
|
{
|
|
rq_unpin_lock(rq, rf);
|
|
raw_spin_unlock(&rq->lock);
|
|
raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
|
|
}
|
|
|
|
#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_);
|
|
}
|
|
|
|
static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
|
|
{
|
|
if (l1 > l2)
|
|
swap(l1, l2);
|
|
|
|
spin_lock(l1);
|
|
spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
|
|
}
|
|
|
|
static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
|
|
{
|
|
if (l1 > l2)
|
|
swap(l1, l2);
|
|
|
|
spin_lock_irq(l1);
|
|
spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
|
|
}
|
|
|
|
static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
|
|
{
|
|
if (l1 > l2)
|
|
swap(l1, l2);
|
|
|
|
raw_spin_lock(l1);
|
|
raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
|
|
extern void set_rq_online (struct rq *rq);
|
|
extern void set_rq_offline(struct rq *rq);
|
|
extern bool sched_smp_initialized;
|
|
|
|
#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);
|
|
|
|
#ifdef CONFIG_SCHED_DEBUG
|
|
extern void print_cfs_stats(struct seq_file *m, int cpu);
|
|
extern void print_rt_stats(struct seq_file *m, int cpu);
|
|
extern void print_dl_stats(struct seq_file *m, int cpu);
|
|
extern void
|
|
print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
extern void
|
|
show_numa_stats(struct task_struct *p, struct seq_file *m);
|
|
extern void
|
|
print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
|
|
unsigned long tpf, unsigned long gsf, unsigned long gpf);
|
|
#endif /* CONFIG_NUMA_BALANCING */
|
|
#endif /* CONFIG_SCHED_DEBUG */
|
|
|
|
extern void init_cfs_rq(struct cfs_rq *cfs_rq);
|
|
extern void init_rt_rq(struct rt_rq *rt_rq);
|
|
extern void init_dl_rq(struct dl_rq *dl_rq);
|
|
|
|
extern void cfs_bandwidth_usage_inc(void);
|
|
extern void cfs_bandwidth_usage_dec(void);
|
|
|
|
#ifdef CONFIG_NO_HZ_COMMON
|
|
enum rq_nohz_flag_bits {
|
|
NOHZ_TICK_STOPPED,
|
|
NOHZ_BALANCE_KICK,
|
|
};
|
|
|
|
#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
|
|
|
|
extern void nohz_balance_exit_idle(unsigned int cpu);
|
|
#else
|
|
static inline void nohz_balance_exit_idle(unsigned int cpu) { }
|
|
#endif
|
|
|
|
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
|
|
struct irqtime {
|
|
u64 tick_delta;
|
|
u64 irq_start_time;
|
|
struct u64_stats_sync sync;
|
|
};
|
|
|
|
DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
|
|
|
|
static inline u64 irq_time_read(int cpu)
|
|
{
|
|
struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
|
|
u64 *cpustat = kcpustat_cpu(cpu).cpustat;
|
|
unsigned int seq;
|
|
u64 total;
|
|
|
|
do {
|
|
seq = __u64_stats_fetch_begin(&irqtime->sync);
|
|
total = cpustat[CPUTIME_SOFTIRQ] + cpustat[CPUTIME_IRQ];
|
|
} while (__u64_stats_fetch_retry(&irqtime->sync, seq));
|
|
|
|
return total;
|
|
}
|
|
#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
|
|
|
|
#ifdef CONFIG_CPU_FREQ
|
|
DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data);
|
|
|
|
/**
|
|
* cpufreq_update_util - Take a note about CPU utilization changes.
|
|
* @rq: Runqueue to carry out the update for.
|
|
* @flags: Update reason flags.
|
|
*
|
|
* This function is called by the scheduler on the CPU whose utilization is
|
|
* being updated.
|
|
*
|
|
* It can only be called from RCU-sched read-side critical sections.
|
|
*
|
|
* The way cpufreq is currently arranged requires it to evaluate the CPU
|
|
* performance state (frequency/voltage) on a regular basis to prevent it from
|
|
* being stuck in a completely inadequate performance level for too long.
|
|
* That is not guaranteed to happen if the updates are only triggered from CFS,
|
|
* though, because they may not be coming in if RT or deadline tasks are active
|
|
* all the time (or there are RT and DL tasks only).
|
|
*
|
|
* As a workaround for that issue, this function is called by the RT and DL
|
|
* sched classes to trigger extra cpufreq updates to prevent it from stalling,
|
|
* but that really is a band-aid. Going forward it should be replaced with
|
|
* solutions targeted more specifically at RT and DL tasks.
|
|
*/
|
|
static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
|
|
{
|
|
struct update_util_data *data;
|
|
|
|
data = rcu_dereference_sched(*this_cpu_ptr(&cpufreq_update_util_data));
|
|
if (data)
|
|
data->func(data, rq_clock(rq), flags);
|
|
}
|
|
|
|
static inline void cpufreq_update_this_cpu(struct rq *rq, unsigned int flags)
|
|
{
|
|
if (cpu_of(rq) == smp_processor_id())
|
|
cpufreq_update_util(rq, flags);
|
|
}
|
|
#else
|
|
static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
|
|
static inline void cpufreq_update_this_cpu(struct rq *rq, unsigned int flags) {}
|
|
#endif /* CONFIG_CPU_FREQ */
|
|
|
|
#ifdef arch_scale_freq_capacity
|
|
#ifndef arch_scale_freq_invariant
|
|
#define arch_scale_freq_invariant() (true)
|
|
#endif
|
|
#else /* arch_scale_freq_capacity */
|
|
#define arch_scale_freq_invariant() (false)
|
|
#endif
|