diff options
Diffstat (limited to 'kernel/sched_fair.c')
-rw-r--r-- | kernel/sched_fair.c | 1759 |
1 files changed, 1759 insertions, 0 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c new file mode 100644 index 0000000..c91973d --- /dev/null +++ b/kernel/sched_fair.c @@ -0,0 +1,1759 @@ +/* + * Completely Fair Scheduling (CFS) Class (SCHED_NORMAL/SCHED_BATCH) + * + * Copyright (C) 2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> + * + * Interactivity improvements by Mike Galbraith + * (C) 2007 Mike Galbraith <efault@gmx.de> + * + * Various enhancements by Dmitry Adamushko. + * (C) 2007 Dmitry Adamushko <dmitry.adamushko@gmail.com> + * + * Group scheduling enhancements by Srivatsa Vaddagiri + * Copyright IBM Corporation, 2007 + * Author: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> + * + * Scaled math optimizations by Thomas Gleixner + * Copyright (C) 2007, Thomas Gleixner <tglx@linutronix.de> + * + * Adaptive scheduling granularity, math enhancements by Peter Zijlstra + * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com> + */ + +#include <linux/latencytop.h> + +/* + * Targeted preemption latency for CPU-bound tasks: + * (default: 20ms * (1 + ilog(ncpus)), units: nanoseconds) + * + * NOTE: this latency value is not the same as the concept of + * 'timeslice length' - timeslices in CFS are of variable length + * and have no persistent notion like in traditional, time-slice + * based scheduling concepts. + * + * (to see the precise effective timeslice length of your workload, + * run vmstat and monitor the context-switches (cs) field) + */ +unsigned int sysctl_sched_latency = 20000000ULL; + +/* + * Minimal preemption granularity for CPU-bound tasks: + * (default: 4 msec * (1 + ilog(ncpus)), units: nanoseconds) + */ +unsigned int sysctl_sched_min_granularity = 4000000ULL; + +/* + * is kept at sysctl_sched_latency / sysctl_sched_min_granularity + */ +static unsigned int sched_nr_latency = 5; + +/* + * After fork, child runs first. (default) If set to 0 then + * parent will (try to) run first. + */ +const_debug unsigned int sysctl_sched_child_runs_first = 1; + +/* + * sys_sched_yield() compat mode + * + * This option switches the agressive yield implementation of the + * old scheduler back on. + */ +unsigned int __read_mostly sysctl_sched_compat_yield; + +/* + * SCHED_OTHER wake-up granularity. + * (default: 5 msec * (1 + ilog(ncpus)), units: nanoseconds) + * + * This option delays the preemption effects of decoupled workloads + * and reduces their over-scheduling. Synchronous workloads will still + * have immediate wakeup/sleep latencies. + */ +unsigned int sysctl_sched_wakeup_granularity = 5000000UL; + +const_debug unsigned int sysctl_sched_migration_cost = 500000UL; + +static const struct sched_class fair_sched_class; + +/************************************************************** + * CFS operations on generic schedulable entities: + */ + +static inline struct task_struct *task_of(struct sched_entity *se) +{ + return container_of(se, struct task_struct, se); +} + +#ifdef CONFIG_FAIR_GROUP_SCHED + +/* cpu runqueue to which this cfs_rq is attached */ +static inline struct rq *rq_of(struct cfs_rq *cfs_rq) +{ + return cfs_rq->rq; +} + +/* An entity is a task if it doesn't "own" a runqueue */ +#define entity_is_task(se) (!se->my_q) + +/* Walk up scheduling entities hierarchy */ +#define for_each_sched_entity(se) \ + for (; se; se = se->parent) + +static inline struct cfs_rq *task_cfs_rq(struct task_struct *p) +{ + return p->se.cfs_rq; +} + +/* runqueue on which this entity is (to be) queued */ +static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se) +{ + return se->cfs_rq; +} + +/* runqueue "owned" by this group */ +static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) +{ + return grp->my_q; +} + +/* Given a group's cfs_rq on one cpu, return its corresponding cfs_rq on + * another cpu ('this_cpu') + */ +static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu) +{ + return cfs_rq->tg->cfs_rq[this_cpu]; +} + +/* Iterate thr' all leaf cfs_rq's on a runqueue */ +#define for_each_leaf_cfs_rq(rq, cfs_rq) \ + list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list) + +/* Do the two (enqueued) entities belong to the same group ? */ +static inline int +is_same_group(struct sched_entity *se, struct sched_entity *pse) +{ + if (se->cfs_rq == pse->cfs_rq) + return 1; + + return 0; +} + +static inline struct sched_entity *parent_entity(struct sched_entity *se) +{ + return se->parent; +} + +/* return depth at which a sched entity is present in the hierarchy */ +static inline int depth_se(struct sched_entity *se) +{ + int depth = 0; + + for_each_sched_entity(se) + depth++; + + return depth; +} + +static void +find_matching_se(struct sched_entity **se, struct sched_entity **pse) +{ + int se_depth, pse_depth; + + /* + * preemption test can be made between sibling entities who are in the + * same cfs_rq i.e who have a common parent. Walk up the hierarchy of + * both tasks until we find their ancestors who are siblings of common + * parent. + */ + + /* First walk up until both entities are at same depth */ + se_depth = depth_se(*se); + pse_depth = depth_se(*pse); + + while (se_depth > pse_depth) { + se_depth--; + *se = parent_entity(*se); + } + + while (pse_depth > se_depth) { + pse_depth--; + *pse = parent_entity(*pse); + } + + while (!is_same_group(*se, *pse)) { + *se = parent_entity(*se); + *pse = parent_entity(*pse); + } +} + +#else /* CONFIG_FAIR_GROUP_SCHED */ + +static inline struct rq *rq_of(struct cfs_rq *cfs_rq) +{ + return container_of(cfs_rq, struct rq, cfs); +} + +#define entity_is_task(se) 1 + +#define for_each_sched_entity(se) \ + for (; se; se = NULL) + +static inline struct cfs_rq *task_cfs_rq(struct task_struct *p) +{ + return &task_rq(p)->cfs; +} + +static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se) +{ + struct task_struct *p = task_of(se); + struct rq *rq = task_rq(p); + + return &rq->cfs; +} + +/* runqueue "owned" by this group */ +static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) +{ + return NULL; +} + +static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu) +{ + return &cpu_rq(this_cpu)->cfs; +} + +#define for_each_leaf_cfs_rq(rq, cfs_rq) \ + for (cfs_rq = &rq->cfs; cfs_rq; cfs_rq = NULL) + +static inline int +is_same_group(struct sched_entity *se, struct sched_entity *pse) +{ + return 1; +} + +static inline struct sched_entity *parent_entity(struct sched_entity *se) +{ + return NULL; +} + +static inline void +find_matching_se(struct sched_entity **se, struct sched_entity **pse) +{ +} + +#endif /* CONFIG_FAIR_GROUP_SCHED */ + + +/************************************************************** + * Scheduling class tree data structure manipulation methods: + */ + +static inline u64 max_vruntime(u64 min_vruntime, u64 vruntime) +{ + s64 delta = (s64)(vruntime - min_vruntime); + if (delta > 0) + min_vruntime = vruntime; + + return min_vruntime; +} + +static inline u64 min_vruntime(u64 min_vruntime, u64 vruntime) +{ + s64 delta = (s64)(vruntime - min_vruntime); + if (delta < 0) + min_vruntime = vruntime; + + return min_vruntime; +} + +static inline s64 entity_key(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + return se->vruntime - cfs_rq->min_vruntime; +} + +static void update_min_vruntime(struct cfs_rq *cfs_rq) +{ + u64 vruntime = cfs_rq->min_vruntime; + + if (cfs_rq->curr) + vruntime = cfs_rq->curr->vruntime; + + if (cfs_rq->rb_leftmost) { + struct sched_entity *se = rb_entry(cfs_rq->rb_leftmost, + struct sched_entity, + run_node); + + if (!cfs_rq->curr) + vruntime = se->vruntime; + else + vruntime = min_vruntime(vruntime, se->vruntime); + } + + cfs_rq->min_vruntime = max_vruntime(cfs_rq->min_vruntime, vruntime); +} + +/* + * Enqueue an entity into the rb-tree: + */ +static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + struct rb_node **link = &cfs_rq->tasks_timeline.rb_node; + struct rb_node *parent = NULL; + struct sched_entity *entry; + s64 key = entity_key(cfs_rq, se); + int leftmost = 1; + + /* + * Find the right place in the rbtree: + */ + while (*link) { + parent = *link; + entry = rb_entry(parent, struct sched_entity, run_node); + /* + * We dont care about collisions. Nodes with + * the same key stay together. + */ + if (key < entity_key(cfs_rq, entry)) { + link = &parent->rb_left; + } else { + link = &parent->rb_right; + leftmost = 0; + } + } + + /* + * Maintain a cache of leftmost tree entries (it is frequently + * used): + */ + if (leftmost) + cfs_rq->rb_leftmost = &se->run_node; + + rb_link_node(&se->run_node, parent, link); + rb_insert_color(&se->run_node, &cfs_rq->tasks_timeline); +} + +static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + if (cfs_rq->rb_leftmost == &se->run_node) { + struct rb_node *next_node; + + next_node = rb_next(&se->run_node); + cfs_rq->rb_leftmost = next_node; + } + + rb_erase(&se->run_node, &cfs_rq->tasks_timeline); +} + +static struct sched_entity *__pick_next_entity(struct cfs_rq *cfs_rq) +{ + struct rb_node *left = cfs_rq->rb_leftmost; + + if (!left) + return NULL; + + return rb_entry(left, struct sched_entity, run_node); +} + +static struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq) +{ + struct rb_node *last = rb_last(&cfs_rq->tasks_timeline); + + if (!last) + return NULL; + + return rb_entry(last, struct sched_entity, run_node); +} + +/************************************************************** + * Scheduling class statistics methods: + */ + +#ifdef CONFIG_SCHED_DEBUG +int sched_nr_latency_handler(struct ctl_table *table, int write, + struct file *filp, void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + int ret = proc_dointvec_minmax(table, write, filp, buffer, lenp, ppos); + + if (ret || !write) + return ret; + + sched_nr_latency = DIV_ROUND_UP(sysctl_sched_latency, + sysctl_sched_min_granularity); + + return 0; +} +#endif + +/* + * delta *= P[w / rw] + */ +static inline unsigned long +calc_delta_weight(unsigned long delta, struct sched_entity *se) +{ + for_each_sched_entity(se) { + delta = calc_delta_mine(delta, + se->load.weight, &cfs_rq_of(se)->load); + } + + return delta; +} + +/* + * delta /= w + */ +static inline unsigned long +calc_delta_fair(unsigned long delta, struct sched_entity *se) +{ + if (unlikely(se->load.weight != NICE_0_LOAD)) + delta = calc_delta_mine(delta, NICE_0_LOAD, &se->load); + + return delta; +} + +/* + * The idea is to set a period in which each task runs once. + * + * When there are too many tasks (sysctl_sched_nr_latency) we have to stretch + * this period because otherwise the slices get too small. + * + * p = (nr <= nl) ? l : l*nr/nl + */ +static u64 __sched_period(unsigned long nr_running) +{ + u64 period = sysctl_sched_latency; + unsigned long nr_latency = sched_nr_latency; + + if (unlikely(nr_running > nr_latency)) { + period = sysctl_sched_min_granularity; + period *= nr_running; + } + + return period; +} + +/* + * We calculate the wall-time slice from the period by taking a part + * proportional to the weight. + * + * s = p*P[w/rw] + */ +static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + unsigned long nr_running = cfs_rq->nr_running; + + if (unlikely(!se->on_rq)) + nr_running++; + + return calc_delta_weight(__sched_period(nr_running), se); +} + +/* + * We calculate the vruntime slice of a to be inserted task + * + * vs = s/w + */ +static u64 sched_vslice(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + return calc_delta_fair(sched_slice(cfs_rq, se), se); +} + +/* + * Update the current task's runtime statistics. Skip current tasks that + * are not in our scheduling class. + */ +static inline void +__update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr, + unsigned long delta_exec) +{ + unsigned long delta_exec_weighted; + + schedstat_set(curr->exec_max, max((u64)delta_exec, curr->exec_max)); + + curr->sum_exec_runtime += delta_exec; + schedstat_add(cfs_rq, exec_clock, delta_exec); + delta_exec_weighted = calc_delta_fair(delta_exec, curr); + curr->vruntime += delta_exec_weighted; + update_min_vruntime(cfs_rq); +} + +static void update_curr(struct cfs_rq *cfs_rq) +{ + struct sched_entity *curr = cfs_rq->curr; + u64 now = rq_of(cfs_rq)->clock; + unsigned long delta_exec; + + if (unlikely(!curr)) + return; + + /* + * Get the amount of time the current task was running + * since the last time we changed load (this cannot + * overflow on 32 bits): + */ + delta_exec = (unsigned long)(now - curr->exec_start); + + __update_curr(cfs_rq, curr, delta_exec); + curr->exec_start = now; + + if (entity_is_task(curr)) { + struct task_struct *curtask = task_of(curr); + + cpuacct_charge(curtask, delta_exec); + account_group_exec_runtime(curtask, delta_exec); + } +} + +static inline void +update_stats_wait_start(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + schedstat_set(se->wait_start, rq_of(cfs_rq)->clock); +} + +/* + * Task is being enqueued - update stats: + */ +static void update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + /* + * Are we enqueueing a waiting task? (for current tasks + * a dequeue/enqueue event is a NOP) + */ + if (se != cfs_rq->curr) + update_stats_wait_start(cfs_rq, se); +} + +static void +update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + schedstat_set(se->wait_max, max(se->wait_max, + rq_of(cfs_rq)->clock - se->wait_start)); + schedstat_set(se->wait_count, se->wait_count + 1); + schedstat_set(se->wait_sum, se->wait_sum + + rq_of(cfs_rq)->clock - se->wait_start); + schedstat_set(se->wait_start, 0); +} + +static inline void +update_stats_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + /* + * Mark the end of the wait period if dequeueing a + * waiting task: + */ + if (se != cfs_rq->curr) + update_stats_wait_end(cfs_rq, se); +} + +/* + * We are picking a new current task - update its stats: + */ +static inline void +update_stats_curr_start(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + /* + * We are starting a new run period: + */ + se->exec_start = rq_of(cfs_rq)->clock; +} + +/************************************************** + * Scheduling class queueing methods: + */ + +#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED +static void +add_cfs_task_weight(struct cfs_rq *cfs_rq, unsigned long weight) +{ + cfs_rq->task_weight += weight; +} +#else +static inline void +add_cfs_task_weight(struct cfs_rq *cfs_rq, unsigned long weight) +{ +} +#endif + +static void +account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + update_load_add(&cfs_rq->load, se->load.weight); + if (!parent_entity(se)) + inc_cpu_load(rq_of(cfs_rq), se->load.weight); + if (entity_is_task(se)) { + add_cfs_task_weight(cfs_rq, se->load.weight); + list_add(&se->group_node, &cfs_rq->tasks); + } + cfs_rq->nr_running++; + se->on_rq = 1; +} + +static void +account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + update_load_sub(&cfs_rq->load, se->load.weight); + if (!parent_entity(se)) + dec_cpu_load(rq_of(cfs_rq), se->load.weight); + if (entity_is_task(se)) { + add_cfs_task_weight(cfs_rq, -se->load.weight); + list_del_init(&se->group_node); + } + cfs_rq->nr_running--; + se->on_rq = 0; +} + +static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ +#ifdef CONFIG_SCHEDSTATS + if (se->sleep_start) { + u64 delta = rq_of(cfs_rq)->clock - se->sleep_start; + struct task_struct *tsk = task_of(se); + + if ((s64)delta < 0) + delta = 0; + + if (unlikely(delta > se->sleep_max)) + se->sleep_max = delta; + + se->sleep_start = 0; + se->sum_sleep_runtime += delta; + + account_scheduler_latency(tsk, delta >> 10, 1); + } + if (se->block_start) { + u64 delta = rq_of(cfs_rq)->clock - se->block_start; + struct task_struct *tsk = task_of(se); + + if ((s64)delta < 0) + delta = 0; + + if (unlikely(delta > se->block_max)) + se->block_max = delta; + + se->block_start = 0; + se->sum_sleep_runtime += delta; + + /* + * Blocking time is in units of nanosecs, so shift by 20 to + * get a milliseconds-range estimation of the amount of + * time that the task spent sleeping: + */ + if (unlikely(prof_on == SLEEP_PROFILING)) { + + profile_hits(SLEEP_PROFILING, (void *)get_wchan(tsk), + delta >> 20); + } + account_scheduler_latency(tsk, delta >> 10, 0); + } +#endif +} + +static void check_spread(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ +#ifdef CONFIG_SCHED_DEBUG + s64 d = se->vruntime - cfs_rq->min_vruntime; + + if (d < 0) + d = -d; + + if (d > 3*sysctl_sched_latency) + schedstat_inc(cfs_rq, nr_spread_over); +#endif +} + +static void +place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial) +{ + u64 vruntime = cfs_rq->min_vruntime; + + /* + * The 'current' period is already promised to the current tasks, + * however the extra weight of the new task will slow them down a + * little, place the new task so that it fits in the slot that + * stays open at the end. + */ + if (initial && sched_feat(START_DEBIT)) + vruntime += sched_vslice(cfs_rq, se); + + if (!initial) { + /* sleeps upto a single latency don't count. */ + if (sched_feat(NEW_FAIR_SLEEPERS)) { + unsigned long thresh = sysctl_sched_latency; + + /* + * Convert the sleeper threshold into virtual time. + * SCHED_IDLE is a special sub-class. We care about + * fairness only relative to other SCHED_IDLE tasks, + * all of which have the same weight. + */ + if (sched_feat(NORMALIZED_SLEEPER) && + task_of(se)->policy != SCHED_IDLE) + thresh = calc_delta_fair(thresh, se); + + vruntime -= thresh; + } + + /* ensure we never gain time by being placed backwards. */ + vruntime = max_vruntime(se->vruntime, vruntime); + } + + se->vruntime = vruntime; +} + +static void +enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup) +{ + /* + * Update run-time statistics of the 'current'. + */ + update_curr(cfs_rq); + account_entity_enqueue(cfs_rq, se); + + if (wakeup) { + place_entity(cfs_rq, se, 0); + enqueue_sleeper(cfs_rq, se); + } + + update_stats_enqueue(cfs_rq, se); + check_spread(cfs_rq, se); + if (se != cfs_rq->curr) + __enqueue_entity(cfs_rq, se); +} + +static void clear_buddies(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + if (cfs_rq->last == se) + cfs_rq->last = NULL; + + if (cfs_rq->next == se) + cfs_rq->next = NULL; +} + +static void +dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep) +{ + /* + * Update run-time statistics of the 'current'. + */ + update_curr(cfs_rq); + + update_stats_dequeue(cfs_rq, se); + if (sleep) { +#ifdef CONFIG_SCHEDSTATS + if (entity_is_task(se)) { + struct task_struct *tsk = task_of(se); + + if (tsk->state & TASK_INTERRUPTIBLE) + se->sleep_start = rq_of(cfs_rq)->clock; + if (tsk->state & TASK_UNINTERRUPTIBLE) + se->block_start = rq_of(cfs_rq)->clock; + } +#endif + } + + clear_buddies(cfs_rq, se); + + if (se != cfs_rq->curr) + __dequeue_entity(cfs_rq, se); + account_entity_dequeue(cfs_rq, se); + update_min_vruntime(cfs_rq); +} + +/* + * Preempt the current task with a newly woken task if needed: + */ +static void +check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr) +{ + unsigned long ideal_runtime, delta_exec; + + ideal_runtime = sched_slice(cfs_rq, curr); + delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime; + if (delta_exec > ideal_runtime) + resched_task(rq_of(cfs_rq)->curr); +} + +static void +set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + /* 'current' is not kept within the tree. */ + if (se->on_rq) { + /* + * Any task has to be enqueued before it get to execute on + * a CPU. So account for the time it spent waiting on the + * runqueue. + */ + update_stats_wait_end(cfs_rq, se); + __dequeue_entity(cfs_rq, se); + } + + update_stats_curr_start(cfs_rq, se); + cfs_rq->curr = se; +#ifdef CONFIG_SCHEDSTATS + /* + * Track our maximum slice length, if the CPU's load is at + * least twice that of our own weight (i.e. dont track it + * when there are only lesser-weight tasks around): + */ + if (rq_of(cfs_rq)->load.weight >= 2*se->load.weight) { + se->slice_max = max(se->slice_max, + se->sum_exec_runtime - se->prev_sum_exec_runtime); + } +#endif + se->prev_sum_exec_runtime = se->sum_exec_runtime; +} + +static int +wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se); + +static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq) +{ + struct sched_entity *se = __pick_next_entity(cfs_rq); + + if (cfs_rq->next && wakeup_preempt_entity(cfs_rq->next, se) < 1) + return cfs_rq->next; + + if (cfs_rq->last && wakeup_preempt_entity(cfs_rq->last, se) < 1) + return cfs_rq->last; + + return se; +} + +static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev) +{ + /* + * If still on the runqueue then deactivate_task() + * was not called and update_curr() has to be done: + */ + if (prev->on_rq) + update_curr(cfs_rq); + + check_spread(cfs_rq, prev); + if (prev->on_rq) { + update_stats_wait_start(cfs_rq, prev); + /* Put 'current' back into the tree. */ + __enqueue_entity(cfs_rq, prev); + } + cfs_rq->curr = NULL; +} + +static void +entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued) +{ + /* + * Update run-time statistics of the 'current'. + */ + update_curr(cfs_rq); + +#ifdef CONFIG_SCHED_HRTICK + /* + * queued ticks are scheduled to match the slice, so don't bother + * validating it and just reschedule. + */ + if (queued) { + resched_task(rq_of(cfs_rq)->curr); + return; + } + /* + * don't let the period tick interfere with the hrtick preemption + */ + if (!sched_feat(DOUBLE_TICK) && + hrtimer_active(&rq_of(cfs_rq)->hrtick_timer)) + return; +#endif + + if (cfs_rq->nr_running > 1 || !sched_feat(WAKEUP_PREEMPT)) + check_preempt_tick(cfs_rq, curr); +} + +/************************************************** + * CFS operations on tasks: + */ + +#ifdef CONFIG_SCHED_HRTICK +static void hrtick_start_fair(struct rq *rq, struct task_struct *p) +{ + struct sched_entity *se = &p->se; + struct cfs_rq *cfs_rq = cfs_rq_of(se); + + WARN_ON(task_rq(p) != rq); + + if (hrtick_enabled(rq) && cfs_rq->nr_running > 1) { + u64 slice = sched_slice(cfs_rq, se); + u64 ran = se->sum_exec_runtime - se->prev_sum_exec_runtime; + s64 delta = slice - ran; + + if (delta < 0) { + if (rq->curr == p) + resched_task(p); + return; + } + + /* + * Don't schedule slices shorter than 10000ns, that just + * doesn't make sense. Rely on vruntime for fairness. + */ + if (rq->curr != p) + delta = max_t(s64, 10000LL, delta); + + hrtick_start(rq, delta); + } +} + +/* + * called from enqueue/dequeue and updates the hrtick when the + * current task is from our class and nr_running is low enough + * to matter. + */ +static void hrtick_update(struct rq *rq) +{ + struct task_struct *curr = rq->curr; + + if (curr->sched_class != &fair_sched_class) + return; + + if (cfs_rq_of(&curr->se)->nr_running < sched_nr_latency) + hrtick_start_fair(rq, curr); +} +#else /* !CONFIG_SCHED_HRTICK */ +static inline void +hrtick_start_fair(struct rq *rq, struct task_struct *p) +{ +} + +static inline void hrtick_update(struct rq *rq) +{ +} +#endif + +/* + * The enqueue_task method is called before nr_running is + * increased. Here we update the fair scheduling stats and + * then put the task into the rbtree: + */ +static void enqueue_task_fair(struct rq *rq, struct task_struct *p, int wakeup) +{ + struct cfs_rq *cfs_rq; + struct sched_entity *se = &p->se; + + for_each_sched_entity(se) { + if (se->on_rq) + break; + cfs_rq = cfs_rq_of(se); + enqueue_entity(cfs_rq, se, wakeup); + wakeup = 1; + } + + hrtick_update(rq); +} + +/* + * The dequeue_task method is called before nr_running is + * decreased. We remove the task from the rbtree and + * update the fair scheduling stats: + */ +static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int sleep) +{ + struct cfs_rq *cfs_rq; + struct sched_entity *se = &p->se; + + for_each_sched_entity(se) { + cfs_rq = cfs_rq_of(se); + dequeue_entity(cfs_rq, se, sleep); + /* Don't dequeue parent if it has other entities besides us */ + if (cfs_rq->load.weight) + break; + sleep = 1; + } + + hrtick_update(rq); +} + +/* + * sched_yield() support is very simple - we dequeue and enqueue. + * + * If compat_yield is turned on then we requeue to the end of the tree. + */ +static void yield_task_fair(struct rq *rq) +{ + struct task_struct *curr = rq->curr; + struct cfs_rq *cfs_rq = task_cfs_rq(curr); + struct sched_entity *rightmost, *se = &curr->se; + + /* + * Are we the only task in the tree? + */ + if (unlikely(cfs_rq->nr_running == 1)) + return; + + clear_buddies(cfs_rq, se); + + if (likely(!sysctl_sched_compat_yield) && curr->policy != SCHED_BATCH) { + update_rq_clock(rq); + /* + * Update run-time statistics of the 'current'. + */ + update_curr(cfs_rq); + + return; + } + /* + * Find the rightmost entry in the rbtree: + */ + rightmost = __pick_last_entity(cfs_rq); + /* + * Already in the rightmost position? + */ + if (unlikely(!rightmost || rightmost->vruntime < se->vruntime)) + return; + + /* + * Minimally necessary key value to be last in the tree: + * Upon rescheduling, sched_class::put_prev_task() will place + * 'current' within the tree based on its new key value. + */ + se->vruntime = rightmost->vruntime + 1; +} + +/* + * wake_idle() will wake a task on an idle cpu if task->cpu is + * not idle and an idle cpu is available. The span of cpus to + * search starts with cpus closest then further out as needed, + * so we always favor a closer, idle cpu. + * Domains may include CPUs that are not usable for migration, + * hence we need to mask them out (cpu_active_map) + * + * Returns the CPU we should wake onto. + */ +#if defined(ARCH_HAS_SCHED_WAKE_IDLE) +static int wake_idle(int cpu, struct task_struct *p) +{ + cpumask_t tmp; + struct sched_domain *sd; + int i; + + /* + * If it is idle, then it is the best cpu to run this task. + * + * This cpu is also the best, if it has more than one task already. + * Siblings must be also busy(in most cases) as they didn't already + * pickup the extra load from this cpu and hence we need not check + * sibling runqueue info. This will avoid the checks and cache miss + * penalities associated with that. + */ + if (idle_cpu(cpu) || cpu_rq(cpu)->cfs.nr_running > 1) + return cpu; + + for_each_domain(cpu, sd) { + if ((sd->flags & SD_WAKE_IDLE) + || ((sd->flags & SD_WAKE_IDLE_FAR) + && !task_hot(p, task_rq(p)->clock, sd))) { + cpus_and(tmp, sd->span, p->cpus_allowed); + cpus_and(tmp, tmp, cpu_active_map); + for_each_cpu_mask_nr(i, tmp) { + if (idle_cpu(i)) { + if (i != task_cpu(p)) { + schedstat_inc(p, + se.nr_wakeups_idle); + } + return i; + } + } + } else { + break; + } + } + return cpu; +} +#else /* !ARCH_HAS_SCHED_WAKE_IDLE*/ +static inline int wake_idle(int cpu, struct task_struct *p) +{ + return cpu; +} +#endif + +#ifdef CONFIG_SMP + +#ifdef CONFIG_FAIR_GROUP_SCHED +/* + * effective_load() calculates the load change as seen from the root_task_group + * + * Adding load to a group doesn't make a group heavier, but can cause movement + * of group shares between cpus. Assuming the shares were perfectly aligned one + * can calculate the shift in shares. + * + * The problem is that perfectly aligning the shares is rather expensive, hence + * we try to avoid doing that too often - see update_shares(), which ratelimits + * this change. + * + * We compensate this by not only taking the current delta into account, but + * also considering the delta between when the shares were last adjusted and + * now. + * + * We still saw a performance dip, some tracing learned us that between + * cgroup:/ and cgroup:/foo balancing the number of affine wakeups increased + * significantly. Therefore try to bias the error in direction of failing + * the affine wakeup. + * + */ +static long effective_load(struct task_group *tg, int cpu, + long wl, long wg) +{ + struct sched_entity *se = tg->se[cpu]; + + if (!tg->parent) + return wl; + + /* + * By not taking the decrease of shares on the other cpu into + * account our error leans towards reducing the affine wakeups. + */ + if (!wl && sched_feat(ASYM_EFF_LOAD)) + return wl; + + for_each_sched_entity(se) { + long S, rw, s, a, b; + long more_w; + + /* + * Instead of using this increment, also add the difference + * between when the shares were last updated and now. + */ + more_w = se->my_q->load.weight - se->my_q->rq_weight; + wl += more_w; + wg += more_w; + + S = se->my_q->tg->shares; + s = se->my_q->shares; + rw = se->my_q->rq_weight; + + a = S*(rw + wl); + b = S*rw + s*wg; + + wl = s*(a-b); + + if (likely(b)) + wl /= b; + + /* + * Assume the group is already running and will + * thus already be accounted for in the weight. + * + * That is, moving shares between CPUs, does not + * alter the group weight. + */ + wg = 0; + } + + return wl; +} + +#else + +static inline unsigned long effective_load(struct task_group *tg, int cpu, + unsigned long wl, unsigned long wg) +{ + return wl; +} + +#endif + +static int +wake_affine(struct sched_domain *this_sd, struct rq *this_rq, + struct task_struct *p, int prev_cpu, int this_cpu, int sync, + int idx, unsigned long load, unsigned long this_load, + unsigned int imbalance) +{ + struct task_struct *curr = this_rq->curr; + struct task_group *tg; + unsigned long tl = this_load; + unsigned long tl_per_task; + unsigned long weight; + int balanced; + + if (!(this_sd->flags & SD_WAKE_AFFINE) || !sched_feat(AFFINE_WAKEUPS)) + return 0; + + if (sync && (curr->se.avg_overlap > sysctl_sched_migration_cost || + p->se.avg_overlap > sysctl_sched_migration_cost)) + sync = 0; + + /* + * If sync wakeup then subtract the (maximum possible) + * effect of the currently running task from the load + * of the current CPU: + */ + if (sync) { + tg = task_group(current); + weight = current->se.load.weight; + + tl += effective_load(tg, this_cpu, -weight, -weight); + load += effective_load(tg, prev_cpu, 0, -weight); + } + + tg = task_group(p); + weight = p->se.load.weight; + + balanced = 100*(tl + effective_load(tg, this_cpu, weight, weight)) <= + imbalance*(load + effective_load(tg, prev_cpu, 0, weight)); + + /* + * If the currently running task will sleep within + * a reasonable amount of time then attract this newly + * woken task: + */ + if (sync && balanced) + return 1; + + schedstat_inc(p, se.nr_wakeups_affine_attempts); + tl_per_task = cpu_avg_load_per_task(this_cpu); + + if (balanced || (tl <= load && tl + target_load(prev_cpu, idx) <= + tl_per_task)) { + /* + * This domain has SD_WAKE_AFFINE and + * p is cache cold in this domain, and + * there is no bad imbalance. + */ + schedstat_inc(this_sd, ttwu_move_affine); + schedstat_inc(p, se.nr_wakeups_affine); + + return 1; + } + return 0; +} + +static int select_task_rq_fair(struct task_struct *p, int sync) +{ + struct sched_domain *sd, *this_sd = NULL; + int prev_cpu, this_cpu, new_cpu; + unsigned long load, this_load; + struct rq *this_rq; + unsigned int imbalance; + int idx; + + prev_cpu = task_cpu(p); + this_cpu = smp_processor_id(); + this_rq = cpu_rq(this_cpu); + new_cpu = prev_cpu; + + if (prev_cpu == this_cpu) + goto out; + /* + * 'this_sd' is the first domain that both + * this_cpu and prev_cpu are present in: + */ + for_each_domain(this_cpu, sd) { + if (cpu_isset(prev_cpu, sd->span)) { + this_sd = sd; + break; + } + } + + if (unlikely(!cpu_isset(this_cpu, p->cpus_allowed))) + goto out; + + /* + * Check for affine wakeup and passive balancing possibilities. + */ + if (!this_sd) + goto out; + + idx = this_sd->wake_idx; + + imbalance = 100 + (this_sd->imbalance_pct - 100) / 2; + + load = source_load(prev_cpu, idx); + this_load = target_load(this_cpu, idx); + + if (wake_affine(this_sd, this_rq, p, prev_cpu, this_cpu, sync, idx, + load, this_load, imbalance)) + return this_cpu; + + /* + * Start passive balancing when half the imbalance_pct + * limit is reached. + */ + if (this_sd->flags & SD_WAKE_BALANCE) { + if (imbalance*this_load <= 100*load) { + schedstat_inc(this_sd, ttwu_move_balance); + schedstat_inc(p, se.nr_wakeups_passive); + return this_cpu; + } + } + +out: + return wake_idle(new_cpu, p); +} +#endif /* CONFIG_SMP */ + +static unsigned long wakeup_gran(struct sched_entity *se) +{ + unsigned long gran = sysctl_sched_wakeup_granularity; + + /* + * More easily preempt - nice tasks, while not making it harder for + * + nice tasks. + */ + if (!sched_feat(ASYM_GRAN) || se->load.weight > NICE_0_LOAD) + gran = calc_delta_fair(sysctl_sched_wakeup_granularity, se); + + return gran; +} + +/* + * Should 'se' preempt 'curr'. + * + * |s1 + * |s2 + * |s3 + * g + * |<--->|c + * + * w(c, s1) = -1 + * w(c, s2) = 0 + * w(c, s3) = 1 + * + */ +static int +wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se) +{ + s64 gran, vdiff = curr->vruntime - se->vruntime; + + if (vdiff <= 0) + return -1; + + gran = wakeup_gran(curr); + if (vdiff > gran) + return 1; + + return 0; +} + +static void set_last_buddy(struct sched_entity *se) +{ + if (likely(task_of(se)->policy != SCHED_IDLE)) { + for_each_sched_entity(se) + cfs_rq_of(se)->last = se; + } +} + +static void set_next_buddy(struct sched_entity *se) +{ + if (likely(task_of(se)->policy != SCHED_IDLE)) { + for_each_sched_entity(se) + cfs_rq_of(se)->next = se; + } +} + +/* + * Preempt the current task with a newly woken task if needed: + */ +static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync) +{ + struct task_struct *curr = rq->curr; + struct sched_entity *se = &curr->se, *pse = &p->se; + + if (unlikely(rt_prio(p->prio))) { + struct cfs_rq *cfs_rq = task_cfs_rq(curr); + + update_rq_clock(rq); + update_curr(cfs_rq); + resched_task(curr); + return; + } + + if (unlikely(p->sched_class != &fair_sched_class)) + return; + + if (unlikely(se == pse)) + return; + + /* + * Only set the backward buddy when the current task is still on the + * rq. This can happen when a wakeup gets interleaved with schedule on + * the ->pre_schedule() or idle_balance() point, either of which can + * drop the rq lock. + * + * Also, during early boot the idle thread is in the fair class, for + * obvious reasons its a bad idea to schedule back to the idle thread. + */ + if (sched_feat(LAST_BUDDY) && likely(se->on_rq && curr != rq->idle)) + set_last_buddy(se); + set_next_buddy(pse); + + /* + * We can come here with TIF_NEED_RESCHED already set from new task + * wake up path. + */ + if (test_tsk_need_resched(curr)) + return; + + /* + * Batch and idle tasks do not preempt (their preemption is driven by + * the tick): + */ + if (unlikely(p->policy != SCHED_NORMAL)) + return; + + /* Idle tasks are by definition preempted by everybody. */ + if (unlikely(curr->policy == SCHED_IDLE)) { + resched_task(curr); + return; + } + + if (!sched_feat(WAKEUP_PREEMPT)) + return; + + if (sched_feat(WAKEUP_OVERLAP) && (sync || + (se->avg_overlap < sysctl_sched_migration_cost && + pse->avg_overlap < sysctl_sched_migration_cost))) { + resched_task(curr); + return; + } + + find_matching_se(&se, &pse); + + while (se) { + BUG_ON(!pse); + + if (wakeup_preempt_entity(se, pse) == 1) { + resched_task(curr); + break; + } + + se = parent_entity(se); + pse = parent_entity(pse); + } +} + +static struct task_struct *pick_next_task_fair(struct rq *rq) +{ + struct task_struct *p; + struct cfs_rq *cfs_rq = &rq->cfs; + struct sched_entity *se; + + if (unlikely(!cfs_rq->nr_running)) + return NULL; + + do { + se = pick_next_entity(cfs_rq); + set_next_entity(cfs_rq, se); + cfs_rq = group_cfs_rq(se); + } while (cfs_rq); + + p = task_of(se); + hrtick_start_fair(rq, p); + + return p; +} + +/* + * Account for a descheduled task: + */ +static void put_prev_task_fair(struct rq *rq, struct task_struct *prev) +{ + struct sched_entity *se = &prev->se; + struct cfs_rq *cfs_rq; + + for_each_sched_entity(se) { + cfs_rq = cfs_rq_of(se); + put_prev_entity(cfs_rq, se); + } +} + +#ifdef CONFIG_SMP +/************************************************** + * Fair scheduling class load-balancing methods: + */ + +/* + * Load-balancing iterator. Note: while the runqueue stays locked + * during the whole iteration, the current task might be + * dequeued so the iterator has to be dequeue-safe. Here we + * achieve that by always pre-iterating before returning + * the current task: + */ +static struct task_struct * +__load_balance_iterator(struct cfs_rq *cfs_rq, struct list_head *next) +{ + struct task_struct *p = NULL; + struct sched_entity *se; + + if (next == &cfs_rq->tasks) + return NULL; + + se = list_entry(next, struct sched_entity, group_node); + p = task_of(se); + cfs_rq->balance_iterator = next->next; + + return p; +} + +static struct task_struct *load_balance_start_fair(void *arg) +{ + struct cfs_rq *cfs_rq = arg; + + return __load_balance_iterator(cfs_rq, cfs_rq->tasks.next); +} + +static struct task_struct *load_balance_next_fair(void *arg) +{ + struct cfs_rq *cfs_rq = arg; + + return __load_balance_iterator(cfs_rq, cfs_rq->balance_iterator); +} + +static unsigned long +__load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, + unsigned long max_load_move, struct sched_domain *sd, + enum cpu_idle_type idle, int *all_pinned, int *this_best_prio, + struct cfs_rq *cfs_rq) +{ + struct rq_iterator cfs_rq_iterator; + + cfs_rq_iterator.start = load_balance_start_fair; + cfs_rq_iterator.next = load_balance_next_fair; + cfs_rq_iterator.arg = cfs_rq; + + return balance_tasks(this_rq, this_cpu, busiest, + max_load_move, sd, idle, all_pinned, + this_best_prio, &cfs_rq_iterator); +} + +#ifdef CONFIG_FAIR_GROUP_SCHED +static unsigned long +load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, + unsigned long max_load_move, + struct sched_domain *sd, enum cpu_idle_type idle, + int *all_pinned, int *this_best_prio) +{ + long rem_load_move = max_load_move; + int busiest_cpu = cpu_of(busiest); + struct task_group *tg; + + rcu_read_lock(); + update_h_load(busiest_cpu); + + list_for_each_entry_rcu(tg, &task_groups, list) { + struct cfs_rq *busiest_cfs_rq = tg->cfs_rq[busiest_cpu]; + unsigned long busiest_h_load = busiest_cfs_rq->h_load; + unsigned long busiest_weight = busiest_cfs_rq->load.weight; + u64 rem_load, moved_load; + + /* + * empty group + */ + if (!busiest_cfs_rq->task_weight) + continue; + + rem_load = (u64)rem_load_move * busiest_weight; + rem_load = div_u64(rem_load, busiest_h_load + 1); + + moved_load = __load_balance_fair(this_rq, this_cpu, busiest, + rem_load, sd, idle, all_pinned, this_best_prio, + tg->cfs_rq[busiest_cpu]); + + if (!moved_load) + continue; + + moved_load *= busiest_h_load; + moved_load = div_u64(moved_load, busiest_weight + 1); + + rem_load_move -= moved_load; + if (rem_load_move < 0) + break; + } + rcu_read_unlock(); + + return max_load_move - rem_load_move; +} +#else +static unsigned long +load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, + unsigned long max_load_move, + struct sched_domain *sd, enum cpu_idle_type idle, + int *all_pinned, int *this_best_prio) +{ + return __load_balance_fair(this_rq, this_cpu, busiest, + max_load_move, sd, idle, all_pinned, + this_best_prio, &busiest->cfs); +} +#endif + +static int +move_one_task_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, + struct sched_domain *sd, enum cpu_idle_type idle) +{ + struct cfs_rq *busy_cfs_rq; + struct rq_iterator cfs_rq_iterator; + + cfs_rq_iterator.start = load_balance_start_fair; + cfs_rq_iterator.next = load_balance_next_fair; + + for_each_leaf_cfs_rq(busiest, busy_cfs_rq) { + /* + * pass busy_cfs_rq argument into + * load_balance_[start|next]_fair iterators + */ + cfs_rq_iterator.arg = busy_cfs_rq; + if (iter_move_one_task(this_rq, this_cpu, busiest, sd, idle, + &cfs_rq_iterator)) + return 1; + } + + return 0; +} +#endif /* CONFIG_SMP */ + +/* + * scheduler tick hitting a task of our scheduling class: + */ +static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued) +{ + struct cfs_rq *cfs_rq; + struct sched_entity *se = &curr->se; + + for_each_sched_entity(se) { + cfs_rq = cfs_rq_of(se); + entity_tick(cfs_rq, se, queued); + } +} + +#define swap(a, b) do { typeof(a) tmp = (a); (a) = (b); (b) = tmp; } while (0) + +/* + * Share the fairness runtime between parent and child, thus the + * total amount of pressure for CPU stays equal - new tasks + * get a chance to run but frequent forkers are not allowed to + * monopolize the CPU. Note: the parent runqueue is locked, + * the child is not running yet. + */ +static void task_new_fair(struct rq *rq, struct task_struct *p) +{ + struct cfs_rq *cfs_rq = task_cfs_rq(p); + struct sched_entity *se = &p->se, *curr = cfs_rq->curr; + int this_cpu = smp_processor_id(); + + sched_info_queued(p); + + update_curr(cfs_rq); + place_entity(cfs_rq, se, 1); + + /* 'curr' will be NULL if the child belongs to a different group */ + if (sysctl_sched_child_runs_first && this_cpu == task_cpu(p) && + curr && curr->vruntime < se->vruntime) { + /* + * Upon rescheduling, sched_class::put_prev_task() will place + * 'current' within the tree based on its new key value. + */ + swap(curr->vruntime, se->vruntime); + resched_task(rq->curr); + } + + enqueue_task_fair(rq, p, 0); +} + +/* + * Priority of the task has changed. Check to see if we preempt + * the current task. + */ +static void prio_changed_fair(struct rq *rq, struct task_struct *p, + int oldprio, int running) +{ + /* + * Reschedule if we are currently running on this runqueue and + * our priority decreased, or if we are not currently running on + * this runqueue and our priority is higher than the current's + */ + if (running) { + if (p->prio > oldprio) + resched_task(rq->curr); + } else + check_preempt_curr(rq, p, 0); +} + +/* + * We switched to the sched_fair class. + */ +static void switched_to_fair(struct rq *rq, struct task_struct *p, + int running) +{ + /* + * We were most likely switched from sched_rt, so + * kick off the schedule if running, otherwise just see + * if we can still preempt the current task. + */ + if (running) + resched_task(rq->curr); + else + check_preempt_curr(rq, p, 0); +} + +/* Account for a task changing its policy or group. + * + * This routine is mostly called to set cfs_rq->curr field when a task + * migrates between groups/classes. + */ +static void set_curr_task_fair(struct rq *rq) +{ + struct sched_entity *se = &rq->curr->se; + + for_each_sched_entity(se) + set_next_entity(cfs_rq_of(se), se); +} + +#ifdef CONFIG_FAIR_GROUP_SCHED +static void moved_group_fair(struct task_struct *p) +{ + struct cfs_rq *cfs_rq = task_cfs_rq(p); + + update_curr(cfs_rq); + place_entity(cfs_rq, &p->se, 1); +} +#endif + +/* + * All the scheduling class methods: + */ +static const struct sched_class fair_sched_class = { + .next = &idle_sched_class, + .enqueue_task = enqueue_task_fair, + .dequeue_task = dequeue_task_fair, + .yield_task = yield_task_fair, + + .check_preempt_curr = check_preempt_wakeup, + + .pick_next_task = pick_next_task_fair, + .put_prev_task = put_prev_task_fair, + +#ifdef CONFIG_SMP + .select_task_rq = select_task_rq_fair, + + .load_balance = load_balance_fair, + .move_one_task = move_one_task_fair, +#endif + + .set_curr_task = set_curr_task_fair, + .task_tick = task_tick_fair, + .task_new = task_new_fair, + + .prio_changed = prio_changed_fair, + .switched_to = switched_to_fair, + +#ifdef CONFIG_FAIR_GROUP_SCHED + .moved_group = moved_group_fair, +#endif +}; + +#ifdef CONFIG_SCHED_DEBUG +static void print_cfs_stats(struct seq_file *m, int cpu) +{ + struct cfs_rq *cfs_rq; + + rcu_read_lock(); + for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq) + print_cfs_rq(m, cpu, cfs_rq); + rcu_read_unlock(); +} +#endif |