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37dc6b50ce
nr_busy_cpus parameter is used by nohz_kick_needed() to find out the number of busy cpus in a sched domain which has SD_SHARE_PKG_RESOURCES flag set. Therefore instead of updating nr_busy_cpus at every level of sched domain, since it is irrelevant, we can update this parameter only at the parent domain of the sd which has this flag set. Introduce a per-cpu parameter sd_busy which represents this parent domain. In nohz_kick_needed() we directly query the nr_busy_cpus parameter associated with the groups of sd_busy. By associating sd_busy with the highest domain which has SD_SHARE_PKG_RESOURCES flag set, we cover all lower level domains which could have this flag set and trigger nohz_idle_balancing if any of the levels have more than one busy cpu. sd_busy is irrelevant for asymmetric load balancing. However sd_asym has been introduced to represent the highest sched domain which has SD_ASYM_PACKING flag set so that it can be queried directly when required. While we are at it, we might as well change the nohz_idle parameter to be updated at the sd_busy domain level alone and not the base domain level of a CPU. This will unify the concept of busy cpus at just one level of sched domain where it is currently used. Signed-off-by: Preeti U Murthy<preeti@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: svaidy@linux.vnet.ibm.com Cc: vincent.guittot@linaro.org Cc: bitbucket@online.de Cc: benh@kernel.crashing.org Cc: anton@samba.org Cc: Morten.Rasmussen@arm.com Cc: pjt@google.com Cc: peterz@infradead.org Cc: mikey@neuling.org Link: http://lkml.kernel.org/r/20131030031252.23426.4417.stgit@preeti.in.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
1417 lines
36 KiB
C
1417 lines
36 KiB
C
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#include <linux/sched.h>
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#include <linux/sched/sysctl.h>
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#include <linux/sched/rt.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/tick.h>
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#include <linux/slab.h>
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#include "cpupri.h"
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#include "cpuacct.h"
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struct rq;
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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 long calc_load_fold_active(struct rq *this_rq);
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extern void update_cpu_load_active(struct rq *this_rq);
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/*
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* Convert user-nice values [ -20 ... 0 ... 19 ]
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* to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
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* and back.
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*/
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#define NICE_TO_PRIO(nice) (MAX_RT_PRIO + (nice) + 20)
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#define PRIO_TO_NICE(prio) ((prio) - MAX_RT_PRIO - 20)
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#define TASK_NICE(p) PRIO_TO_NICE((p)->static_prio)
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/*
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* 'User priority' is the nice value converted to something we
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* can work with better when scaling various scheduler parameters,
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* it's a [ 0 ... 39 ] range.
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*/
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#define USER_PRIO(p) ((p)-MAX_RT_PRIO)
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#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio)
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#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO))
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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. BITS_PER_LONG > 32). The costs for increasing resolution
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* when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the
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* increased costs.
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*/
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#if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load */
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# define SCHED_LOAD_RESOLUTION 10
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# define scale_load(w) ((w) << SCHED_LOAD_RESOLUTION)
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# define scale_load_down(w) ((w) >> SCHED_LOAD_RESOLUTION)
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#else
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# define SCHED_LOAD_RESOLUTION 0
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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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#define SCHED_LOAD_SHIFT (10 + SCHED_LOAD_RESOLUTION)
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#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT)
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#define NICE_0_LOAD SCHED_LOAD_SCALE
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#define NICE_0_SHIFT SCHED_LOAD_SHIFT
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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 rt_policy(int policy)
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{
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if (policy == SCHED_FIFO || policy == SCHED_RR)
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return 1;
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return 0;
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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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/*
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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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};
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extern struct mutex sched_domains_mutex;
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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 hierarchal_quota;
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u64 runtime_expires;
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int idle, timer_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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atomic_long_t load_avg;
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atomic_t runnable_avg;
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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 unregister_fair_sched_group(struct task_group *tg, int cpu);
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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 int sched_group_set_shares(struct task_group *tg, unsigned long shares);
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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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#endif
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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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* Under CFS, load is tracked on a per-entity basis and aggregated up.
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* This allows for the description of both thread and group usage (in
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* the FAIR_GROUP_SCHED case).
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*/
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unsigned long runnable_load_avg, blocked_load_avg;
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atomic64_t decay_counter;
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u64 last_decay;
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atomic_long_t removed_load;
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#ifdef CONFIG_FAIR_GROUP_SCHED
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/* Required to track per-cpu representation of a task_group */
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u32 tg_runnable_contrib;
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unsigned long tg_load_contrib;
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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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/* 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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#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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#endif
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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: */
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raw_spinlock_t rt_runtime_lock;
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#ifdef CONFIG_RT_GROUP_SCHED
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unsigned long rt_nr_boosted;
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struct rq *rq;
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struct task_group *tg;
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#endif
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};
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#ifdef CONFIG_SMP
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/*
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* We add the notion of a root-domain which will be used to define per-domain
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* variables. Each exclusive cpuset essentially defines an island domain by
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* fully partitioning the member cpus from any other cpuset. Whenever a new
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* exclusive cpuset is created, we also create and attach a new root-domain
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* object.
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*
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*/
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struct root_domain {
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atomic_t refcount;
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atomic_t rto_count;
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struct rcu_head rcu;
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cpumask_var_t span;
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cpumask_var_t online;
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/*
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* The "RT overload" flag: it gets set if a CPU has more than
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* one runnable RT task.
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*/
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cpumask_var_t rto_mask;
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struct cpupri cpupri;
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};
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extern struct root_domain def_root_domain;
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#endif /* CONFIG_SMP */
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/*
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* This is the main, per-CPU runqueue data structure.
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*
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* Locking rule: those places that want to lock multiple runqueues
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* (such as the load balancing or the thread migration code), lock
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* acquire operations must be ordered by ascending &runqueue.
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*/
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struct rq {
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/* runqueue lock: */
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raw_spinlock_t lock;
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/*
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* nr_running and cpu_load should be in the same cacheline because
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* remote CPUs use both these fields when doing load calculation.
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*/
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unsigned int nr_running;
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#ifdef CONFIG_NUMA_BALANCING
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unsigned int nr_numa_running;
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unsigned int nr_preferred_running;
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#endif
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#define CPU_LOAD_IDX_MAX 5
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unsigned long cpu_load[CPU_LOAD_IDX_MAX];
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unsigned long last_load_update_tick;
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#ifdef CONFIG_NO_HZ_COMMON
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u64 nohz_stamp;
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unsigned long nohz_flags;
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#endif
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#ifdef CONFIG_NO_HZ_FULL
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unsigned long last_sched_tick;
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#endif
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int skip_clock_update;
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/* capture load from *all* tasks on this cpu: */
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struct load_weight load;
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unsigned long nr_load_updates;
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u64 nr_switches;
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struct cfs_rq cfs;
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struct rt_rq rt;
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#ifdef CONFIG_FAIR_GROUP_SCHED
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/* list of leaf cfs_rq on this cpu: */
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struct list_head leaf_cfs_rq_list;
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#endif /* CONFIG_FAIR_GROUP_SCHED */
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#ifdef CONFIG_RT_GROUP_SCHED
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struct list_head leaf_rt_rq_list;
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#endif
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/*
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* This is part of a global counter where only the total sum
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* over all CPUs matters. A task can increase this counter on
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* one CPU and if it got migrated afterwards it may decrease
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* it on another CPU. Always updated under the runqueue lock:
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*/
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unsigned long nr_uninterruptible;
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struct task_struct *curr, *idle, *stop;
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unsigned long next_balance;
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struct mm_struct *prev_mm;
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u64 clock;
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u64 clock_task;
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atomic_t nr_iowait;
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#ifdef CONFIG_SMP
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struct root_domain *rd;
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struct sched_domain *sd;
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unsigned long cpu_power;
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unsigned char idle_balance;
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/* For active balancing */
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int post_schedule;
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int active_balance;
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int push_cpu;
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struct cpu_stop_work active_balance_work;
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/* cpu of this runqueue: */
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int cpu;
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int online;
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struct list_head cfs_tasks;
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u64 rt_avg;
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u64 age_stamp;
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u64 idle_stamp;
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u64 avg_idle;
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/* This is used to determine avg_idle's max value */
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u64 max_idle_balance_cost;
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#endif
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#ifdef CONFIG_IRQ_TIME_ACCOUNTING
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u64 prev_irq_time;
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#endif
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#ifdef CONFIG_PARAVIRT
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u64 prev_steal_time;
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|
#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
|
|
|
|
struct sched_avg avg;
|
|
};
|
|
|
|
static inline int cpu_of(struct rq *rq)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
return rq->cpu;
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
DECLARE_PER_CPU(struct rq, runqueues);
|
|
|
|
#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu)))
|
|
#define this_rq() (&__get_cpu_var(runqueues))
|
|
#define task_rq(p) cpu_rq(task_cpu(p))
|
|
#define cpu_curr(cpu) (cpu_rq(cpu)->curr)
|
|
#define raw_rq() (&__raw_get_cpu_var(runqueues))
|
|
|
|
static inline u64 rq_clock(struct rq *rq)
|
|
{
|
|
return rq->clock;
|
|
}
|
|
|
|
static inline u64 rq_clock_task(struct rq *rq)
|
|
{
|
|
return rq->clock_task;
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
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
|
|
|
|
#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 *, sd_numa);
|
|
DECLARE_PER_CPU(struct sched_domain *, sd_busy);
|
|
DECLARE_PER_CPU(struct sched_domain *, sd_asym);
|
|
|
|
struct sched_group_power {
|
|
atomic_t ref;
|
|
/*
|
|
* CPU power of this group, SCHED_LOAD_SCALE being max power for a
|
|
* single CPU.
|
|
*/
|
|
unsigned int power, power_orig;
|
|
unsigned long next_update;
|
|
int imbalance; /* XXX unrelated to power but shared group state */
|
|
/*
|
|
* Number of busy cpus in this group.
|
|
*/
|
|
atomic_t nr_busy_cpus;
|
|
|
|
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_power *sgp;
|
|
|
|
/*
|
|
* 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->sgp->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);
|
|
|
|
#endif /* CONFIG_SMP */
|
|
|
|
#include "stats.h"
|
|
#include "auto_group.h"
|
|
|
|
#ifdef CONFIG_CGROUP_SCHED
|
|
|
|
/*
|
|
* Return the group to which this tasks belongs.
|
|
*
|
|
* We cannot use task_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
|
|
p->se.cfs_rq = tg->cfs_rq[cpu];
|
|
p->se.parent = tg->se[cpu];
|
|
#endif
|
|
|
|
#ifdef CONFIG_RT_GROUP_SCHED
|
|
p->rt.rt_rq = tg->rt_rq[cpu];
|
|
p->rt.parent = tg->rt_se[cpu];
|
|
#endif
|
|
}
|
|
|
|
#else /* CONFIG_CGROUP_SCHED */
|
|
|
|
static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
|
|
static inline struct task_group *task_group(struct task_struct *p)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
#endif /* CONFIG_CGROUP_SCHED */
|
|
|
|
static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
|
|
{
|
|
set_task_rq(p, cpu);
|
|
#ifdef CONFIG_SMP
|
|
/*
|
|
* After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
|
|
* successfuly executed on another CPU. We must ensure that updates of
|
|
* per-task data have been completed by this moment.
|
|
*/
|
|
smp_wmb();
|
|
task_thread_info(p)->cpu = cpu;
|
|
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)
|
|
static __always_inline bool static_branch__true(struct static_key *key)
|
|
{
|
|
return static_key_true(key); /* Not out of line branch. */
|
|
}
|
|
|
|
static __always_inline bool static_branch__false(struct static_key *key)
|
|
{
|
|
return static_key_false(key); /* Out of line branch. */
|
|
}
|
|
|
|
#define SCHED_FEAT(name, enabled) \
|
|
static __always_inline bool static_branch_##name(struct static_key *key) \
|
|
{ \
|
|
return static_branch__##enabled(key); \
|
|
}
|
|
|
|
#include "features.h"
|
|
|
|
#undef SCHED_FEAT
|
|
|
|
extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
|
|
#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
|
|
#else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */
|
|
#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
|
|
#endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
|
|
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
#define sched_feat_numa(x) sched_feat(x)
|
|
#ifdef CONFIG_SCHED_DEBUG
|
|
#define numabalancing_enabled sched_feat_numa(NUMA)
|
|
#else
|
|
extern bool numabalancing_enabled;
|
|
#endif /* CONFIG_SCHED_DEBUG */
|
|
#else
|
|
#define sched_feat_numa(x) (0)
|
|
#define numabalancing_enabled (0)
|
|
#endif /* CONFIG_NUMA_BALANCING */
|
|
|
|
static inline u64 global_rt_period(void)
|
|
{
|
|
return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
|
|
}
|
|
|
|
static inline u64 global_rt_runtime(void)
|
|
{
|
|
if (sysctl_sched_rt_runtime < 0)
|
|
return RUNTIME_INF;
|
|
|
|
return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
|
|
}
|
|
|
|
|
|
|
|
static inline int task_current(struct rq *rq, struct task_struct *p)
|
|
{
|
|
return rq->curr == p;
|
|
}
|
|
|
|
static inline int task_running(struct rq *rq, struct task_struct *p)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
return p->on_cpu;
|
|
#else
|
|
return task_current(rq, p);
|
|
#endif
|
|
}
|
|
|
|
|
|
#ifndef prepare_arch_switch
|
|
# define prepare_arch_switch(next) do { } while (0)
|
|
#endif
|
|
#ifndef finish_arch_switch
|
|
# define finish_arch_switch(prev) do { } while (0)
|
|
#endif
|
|
#ifndef finish_arch_post_lock_switch
|
|
# define finish_arch_post_lock_switch() do { } while (0)
|
|
#endif
|
|
|
|
#ifndef __ARCH_WANT_UNLOCKED_CTXSW
|
|
static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
/*
|
|
* We can optimise this out completely for !SMP, because the
|
|
* SMP rebalancing from interrupt is the only thing that cares
|
|
* here.
|
|
*/
|
|
next->on_cpu = 1;
|
|
#endif
|
|
}
|
|
|
|
static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
/*
|
|
* After ->on_cpu is cleared, the task can be moved to a different CPU.
|
|
* We must ensure this doesn't happen until the switch is completely
|
|
* finished.
|
|
*/
|
|
smp_wmb();
|
|
prev->on_cpu = 0;
|
|
#endif
|
|
#ifdef CONFIG_DEBUG_SPINLOCK
|
|
/* this is a valid case when another task releases the spinlock */
|
|
rq->lock.owner = current;
|
|
#endif
|
|
/*
|
|
* If we are tracking spinlock dependencies then we have to
|
|
* fix up the runqueue lock - which gets 'carried over' from
|
|
* prev into current:
|
|
*/
|
|
spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
|
|
|
|
raw_spin_unlock_irq(&rq->lock);
|
|
}
|
|
|
|
#else /* __ARCH_WANT_UNLOCKED_CTXSW */
|
|
static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
/*
|
|
* We can optimise this out completely for !SMP, because the
|
|
* SMP rebalancing from interrupt is the only thing that cares
|
|
* here.
|
|
*/
|
|
next->on_cpu = 1;
|
|
#endif
|
|
raw_spin_unlock(&rq->lock);
|
|
}
|
|
|
|
static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
/*
|
|
* After ->on_cpu is cleared, the task can be moved to a different CPU.
|
|
* We must ensure this doesn't happen until the switch is completely
|
|
* finished.
|
|
*/
|
|
smp_wmb();
|
|
prev->on_cpu = 0;
|
|
#endif
|
|
local_irq_enable();
|
|
}
|
|
#endif /* __ARCH_WANT_UNLOCKED_CTXSW */
|
|
|
|
/*
|
|
* 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
|
|
|
|
/*
|
|
* Nice levels are multiplicative, with a gentle 10% change for every
|
|
* nice level changed. I.e. when a CPU-bound task goes from nice 0 to
|
|
* nice 1, it will get ~10% less CPU time than another CPU-bound task
|
|
* that remained on nice 0.
|
|
*
|
|
* The "10% effect" is relative and cumulative: from _any_ nice level,
|
|
* if you go up 1 level, it's -10% CPU usage, if you go down 1 level
|
|
* it's +10% CPU usage. (to achieve that we use a multiplier of 1.25.
|
|
* If a task goes up by ~10% and another task goes down by ~10% then
|
|
* the relative distance between them is ~25%.)
|
|
*/
|
|
static const int prio_to_weight[40] = {
|
|
/* -20 */ 88761, 71755, 56483, 46273, 36291,
|
|
/* -15 */ 29154, 23254, 18705, 14949, 11916,
|
|
/* -10 */ 9548, 7620, 6100, 4904, 3906,
|
|
/* -5 */ 3121, 2501, 1991, 1586, 1277,
|
|
/* 0 */ 1024, 820, 655, 526, 423,
|
|
/* 5 */ 335, 272, 215, 172, 137,
|
|
/* 10 */ 110, 87, 70, 56, 45,
|
|
/* 15 */ 36, 29, 23, 18, 15,
|
|
};
|
|
|
|
/*
|
|
* Inverse (2^32/x) values of the prio_to_weight[] array, precalculated.
|
|
*
|
|
* In cases where the weight does not change often, we can use the
|
|
* precalculated inverse to speed up arithmetics by turning divisions
|
|
* into multiplications:
|
|
*/
|
|
static const u32 prio_to_wmult[40] = {
|
|
/* -20 */ 48388, 59856, 76040, 92818, 118348,
|
|
/* -15 */ 147320, 184698, 229616, 287308, 360437,
|
|
/* -10 */ 449829, 563644, 704093, 875809, 1099582,
|
|
/* -5 */ 1376151, 1717300, 2157191, 2708050, 3363326,
|
|
/* 0 */ 4194304, 5237765, 6557202, 8165337, 10153587,
|
|
/* 5 */ 12820798, 15790321, 19976592, 24970740, 31350126,
|
|
/* 10 */ 39045157, 49367440, 61356676, 76695844, 95443717,
|
|
/* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153,
|
|
};
|
|
|
|
#define ENQUEUE_WAKEUP 1
|
|
#define ENQUEUE_HEAD 2
|
|
#ifdef CONFIG_SMP
|
|
#define ENQUEUE_WAKING 4 /* sched_class::task_waking was called */
|
|
#else
|
|
#define ENQUEUE_WAKING 0
|
|
#endif
|
|
|
|
#define DEQUEUE_SLEEP 1
|
|
|
|
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);
|
|
|
|
struct task_struct * (*pick_next_task) (struct rq *rq);
|
|
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, int next_cpu);
|
|
|
|
void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
|
|
void (*post_schedule) (struct rq *this_rq);
|
|
void (*task_waking) (struct task_struct *task);
|
|
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 (*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);
|
|
|
|
#ifdef CONFIG_FAIR_GROUP_SCHED
|
|
void (*task_move_group) (struct task_struct *p, int on_rq);
|
|
#endif
|
|
};
|
|
|
|
#define sched_class_highest (&stop_sched_class)
|
|
#define for_each_class(class) \
|
|
for (class = sched_class_highest; class; class = class->next)
|
|
|
|
extern const struct sched_class stop_sched_class;
|
|
extern const struct sched_class rt_sched_class;
|
|
extern const struct sched_class fair_sched_class;
|
|
extern const struct sched_class idle_sched_class;
|
|
|
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
extern void update_group_power(struct sched_domain *sd, int cpu);
|
|
|
|
extern void trigger_load_balance(struct rq *rq, int cpu);
|
|
extern void idle_balance(int this_cpu, struct rq *this_rq);
|
|
|
|
extern void idle_enter_fair(struct rq *this_rq);
|
|
extern void idle_exit_fair(struct rq *this_rq);
|
|
|
|
#else /* CONFIG_SMP */
|
|
|
|
static inline void idle_balance(int cpu, struct rq *rq)
|
|
{
|
|
}
|
|
|
|
#endif
|
|
|
|
extern void sysrq_sched_debug_show(void);
|
|
extern void sched_init_granularity(void);
|
|
extern void update_max_interval(void);
|
|
extern void init_sched_rt_class(void);
|
|
extern void init_sched_fair_class(void);
|
|
|
|
extern void resched_task(struct task_struct *p);
|
|
extern void resched_cpu(int cpu);
|
|
|
|
extern struct rt_bandwidth def_rt_bandwidth;
|
|
extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
|
|
|
|
extern void update_idle_cpu_load(struct rq *this_rq);
|
|
|
|
extern void init_task_runnable_average(struct task_struct *p);
|
|
|
|
#ifdef CONFIG_PARAVIRT
|
|
static inline u64 steal_ticks(u64 steal)
|
|
{
|
|
if (unlikely(steal > NSEC_PER_SEC))
|
|
return div_u64(steal, TICK_NSEC);
|
|
|
|
return __iter_div_u64_rem(steal, TICK_NSEC, &steal);
|
|
}
|
|
#endif
|
|
|
|
static inline void inc_nr_running(struct rq *rq)
|
|
{
|
|
rq->nr_running++;
|
|
|
|
#ifdef CONFIG_NO_HZ_FULL
|
|
if (rq->nr_running == 2) {
|
|
if (tick_nohz_full_cpu(rq->cpu)) {
|
|
/* Order rq->nr_running write against the IPI */
|
|
smp_wmb();
|
|
smp_send_reschedule(rq->cpu);
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
static inline void dec_nr_running(struct rq *rq)
|
|
{
|
|
rq->nr_running--;
|
|
}
|
|
|
|
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);
|
|
static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
|
|
{
|
|
rq->rt_avg += rt_delta;
|
|
sched_avg_update(rq);
|
|
}
|
|
#else
|
|
static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
|
|
static inline void sched_avg_update(struct rq *rq) { }
|
|
#endif
|
|
|
|
extern void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period);
|
|
|
|
#ifdef CONFIG_SMP
|
|
#ifdef CONFIG_PREEMPT
|
|
|
|
static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
|
|
|
|
/*
|
|
* fair double_lock_balance: Safely acquires both rq->locks in a fair
|
|
* way at the expense of forcing extra atomic operations in all
|
|
* invocations. This assures that the double_lock is acquired using the
|
|
* same underlying policy as the spinlock_t on this architecture, which
|
|
* reduces latency compared to the unfair variant below. However, it
|
|
* also adds more overhead and therefore may reduce throughput.
|
|
*/
|
|
static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
|
|
__releases(this_rq->lock)
|
|
__acquires(busiest->lock)
|
|
__acquires(this_rq->lock)
|
|
{
|
|
raw_spin_unlock(&this_rq->lock);
|
|
double_rq_lock(this_rq, busiest);
|
|
|
|
return 1;
|
|
}
|
|
|
|
#else
|
|
/*
|
|
* Unfair double_lock_balance: Optimizes throughput at the expense of
|
|
* latency by eliminating extra atomic operations when the locks are
|
|
* already in proper order on entry. This favors lower cpu-ids and will
|
|
* grant the double lock to lower cpus over higher ids under contention,
|
|
* regardless of entry order into the function.
|
|
*/
|
|
static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
|
|
__releases(this_rq->lock)
|
|
__acquires(busiest->lock)
|
|
__acquires(this_rq->lock)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (unlikely(!raw_spin_trylock(&busiest->lock))) {
|
|
if (busiest < this_rq) {
|
|
raw_spin_unlock(&this_rq->lock);
|
|
raw_spin_lock(&busiest->lock);
|
|
raw_spin_lock_nested(&this_rq->lock,
|
|
SINGLE_DEPTH_NESTING);
|
|
ret = 1;
|
|
} else
|
|
raw_spin_lock_nested(&busiest->lock,
|
|
SINGLE_DEPTH_NESTING);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
#endif /* CONFIG_PREEMPT */
|
|
|
|
/*
|
|
* double_lock_balance - lock the busiest runqueue, this_rq is locked already.
|
|
*/
|
|
static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
|
|
{
|
|
if (unlikely(!irqs_disabled())) {
|
|
/* printk() doesn't work good under rq->lock */
|
|
raw_spin_unlock(&this_rq->lock);
|
|
BUG_ON(1);
|
|
}
|
|
|
|
return _double_lock_balance(this_rq, busiest);
|
|
}
|
|
|
|
static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
|
|
__releases(busiest->lock)
|
|
{
|
|
raw_spin_unlock(&busiest->lock);
|
|
lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
|
|
}
|
|
|
|
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_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);
|
|
}
|
|
|
|
#else /* CONFIG_SMP */
|
|
|
|
/*
|
|
* double_rq_lock - safely lock two runqueues
|
|
*
|
|
* Note this does not disable interrupts like task_rq_lock,
|
|
* you need to do so manually before calling.
|
|
*/
|
|
static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
|
|
__acquires(rq1->lock)
|
|
__acquires(rq2->lock)
|
|
{
|
|
BUG_ON(!irqs_disabled());
|
|
BUG_ON(rq1 != rq2);
|
|
raw_spin_lock(&rq1->lock);
|
|
__acquire(rq2->lock); /* Fake it out ;) */
|
|
}
|
|
|
|
/*
|
|
* double_rq_unlock - safely unlock two runqueues
|
|
*
|
|
* Note this does not restore interrupts like task_rq_unlock,
|
|
* you need to do so manually after calling.
|
|
*/
|
|
static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
|
|
__releases(rq1->lock)
|
|
__releases(rq2->lock)
|
|
{
|
|
BUG_ON(rq1 != rq2);
|
|
raw_spin_unlock(&rq1->lock);
|
|
__release(rq2->lock);
|
|
}
|
|
|
|
#endif
|
|
|
|
extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
|
|
extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
|
|
extern void print_cfs_stats(struct seq_file *m, int cpu);
|
|
extern void print_rt_stats(struct seq_file *m, int cpu);
|
|
|
|
extern void init_cfs_rq(struct cfs_rq *cfs_rq);
|
|
extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq);
|
|
|
|
extern void cfs_bandwidth_usage_inc(void);
|
|
extern void cfs_bandwidth_usage_dec(void);
|
|
|
|
#ifdef CONFIG_NO_HZ_COMMON
|
|
enum rq_nohz_flag_bits {
|
|
NOHZ_TICK_STOPPED,
|
|
NOHZ_BALANCE_KICK,
|
|
};
|
|
|
|
#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
|
|
#endif
|
|
|
|
#ifdef CONFIG_IRQ_TIME_ACCOUNTING
|
|
|
|
DECLARE_PER_CPU(u64, cpu_hardirq_time);
|
|
DECLARE_PER_CPU(u64, cpu_softirq_time);
|
|
|
|
#ifndef CONFIG_64BIT
|
|
DECLARE_PER_CPU(seqcount_t, irq_time_seq);
|
|
|
|
static inline void irq_time_write_begin(void)
|
|
{
|
|
__this_cpu_inc(irq_time_seq.sequence);
|
|
smp_wmb();
|
|
}
|
|
|
|
static inline void irq_time_write_end(void)
|
|
{
|
|
smp_wmb();
|
|
__this_cpu_inc(irq_time_seq.sequence);
|
|
}
|
|
|
|
static inline u64 irq_time_read(int cpu)
|
|
{
|
|
u64 irq_time;
|
|
unsigned seq;
|
|
|
|
do {
|
|
seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu));
|
|
irq_time = per_cpu(cpu_softirq_time, cpu) +
|
|
per_cpu(cpu_hardirq_time, cpu);
|
|
} while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq));
|
|
|
|
return irq_time;
|
|
}
|
|
#else /* CONFIG_64BIT */
|
|
static inline void irq_time_write_begin(void)
|
|
{
|
|
}
|
|
|
|
static inline void irq_time_write_end(void)
|
|
{
|
|
}
|
|
|
|
static inline u64 irq_time_read(int cpu)
|
|
{
|
|
return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu);
|
|
}
|
|
#endif /* CONFIG_64BIT */
|
|
#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
|