* Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
*/
+#include <linux/latencytop.h>
+
/*
* Targeted preemption latency for CPU-bound tasks:
- * (default: 20ms, units: nanoseconds)
+ * (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.
- * (to see the precise effective timeslice length of your workload,
- * run vmstat and monitor the context-switches field)
+ * 'timeslice length' - timeslices in CFS are of variable length
+ * and have no persistent notion like in traditional, time-slice
+ * based scheduling concepts.
*
- * On SMP systems the value of this is multiplied by the log2 of the
- * number of CPUs. (i.e. factor 2x on 2-way systems, 3x on 4-way
- * systems, 4x on 8-way systems, 5x on 16-way systems, etc.)
- * Targeted preemption latency for CPU-bound tasks:
+ * (to see the precise effective timeslice length of your workload,
+ * run vmstat and monitor the context-switches (cs) field)
*/
-const_debug unsigned int sysctl_sched_latency = 20000000ULL;
+unsigned int sysctl_sched_latency = 20000000ULL;
/*
- * After fork, child runs first. (default) If set to 0 then
- * parent will (try to) run first.
+ * Minimal preemption granularity for CPU-bound tasks:
+ * (default: 4 msec * (1 + ilog(ncpus)), units: nanoseconds)
*/
-const_debug unsigned int sysctl_sched_child_runs_first = 1;
+unsigned int sysctl_sched_min_granularity = 4000000ULL;
/*
- * Minimal preemption granularity for CPU-bound tasks:
- * (default: 2 msec, units: nanoseconds)
+ * is kept at sysctl_sched_latency / sysctl_sched_min_granularity
*/
-unsigned int sysctl_sched_min_granularity __read_mostly = 2000000ULL;
+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
/*
* SCHED_BATCH wake-up granularity.
- * (default: 25 msec, units: nanoseconds)
+ * (default: 10 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.
*/
-const_debug unsigned int sysctl_sched_batch_wakeup_granularity = 25000000UL;
+unsigned int sysctl_sched_batch_wakeup_granularity = 10000000UL;
/*
* SCHED_OTHER wake-up granularity.
- * (default: 1 msec, units: nanoseconds)
+ * (default: 10 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.
*/
-const_debug unsigned int sysctl_sched_wakeup_granularity = 1000000UL;
+unsigned int sysctl_sched_wakeup_granularity = 10000000UL;
-unsigned int sysctl_sched_runtime_limit __read_mostly;
-
-extern struct sched_class fair_sched_class;
+const_debug unsigned int sysctl_sched_migration_cost = 500000UL;
/**************************************************************
* CFS operations on generic schedulable entities:
* Scheduling class tree data structure manipulation methods:
*/
-static inline void
-set_leftmost(struct cfs_rq *cfs_rq, struct rb_node *leftmost)
+static inline u64 max_vruntime(u64 min_vruntime, u64 vruntime)
{
- struct sched_entity *se;
+ s64 delta = (s64)(vruntime - min_vruntime);
+ if (delta > 0)
+ min_vruntime = vruntime;
- cfs_rq->rb_leftmost = leftmost;
- if (leftmost) {
- se = rb_entry(leftmost, struct sched_entity, run_node);
- cfs_rq->min_vruntime = max(se->vruntime,
- cfs_rq->min_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;
}
/*
* Enqueue an entity into the rb-tree:
*/
-static void
-__enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
+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 = se->fair_key;
+ s64 key = entity_key(cfs_rq, se);
int leftmost = 1;
/*
* We dont care about collisions. Nodes with
* the same key stay together.
*/
- if (key - entry->fair_key < 0) {
+ if (key < entity_key(cfs_rq, entry)) {
link = &parent->rb_left;
} else {
link = &parent->rb_right;
* used):
*/
if (leftmost)
- set_leftmost(cfs_rq, &se->run_node);
+ 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);
- update_load_add(&cfs_rq->load, se->load.weight);
- cfs_rq->nr_running++;
- se->on_rq = 1;
-
- schedstat_add(cfs_rq, wait_runtime, se->wait_runtime);
}
-static void
-__dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
+static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
if (cfs_rq->rb_leftmost == &se->run_node)
- set_leftmost(cfs_rq, rb_next(&se->run_node));
+ cfs_rq->rb_leftmost = rb_next(&se->run_node);
rb_erase(&se->run_node, &cfs_rq->tasks_timeline);
- update_load_sub(&cfs_rq->load, se->load.weight);
- cfs_rq->nr_running--;
- se->on_rq = 0;
-
- schedstat_add(cfs_rq, wait_runtime, -se->wait_runtime);
}
static inline struct rb_node *first_fair(struct cfs_rq *cfs_rq)
return rb_entry(first_fair(cfs_rq), struct sched_entity, run_node);
}
+static inline struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
+{
+ struct rb_node **link = &cfs_rq->tasks_timeline.rb_node;
+ struct sched_entity *se = NULL;
+ struct rb_node *parent;
+
+ while (*link) {
+ parent = *link;
+ se = rb_entry(parent, struct sched_entity, run_node);
+ link = &parent->rb_right;
+ }
+
+ return se;
+}
+
/**************************************************************
* 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
+
+/*
+ * 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 =
- sysctl_sched_latency / sysctl_sched_min_granularity;
+ unsigned long nr_latency = sched_nr_latency;
if (unlikely(nr_running > nr_latency)) {
+ period = sysctl_sched_min_granularity;
period *= nr_running;
- do_div(period, nr_latency);
}
return period;
}
+/*
+ * We calculate the wall-time slice from the period by taking a part
+ * proportional to the weight.
+ *
+ * s = p*w/rw
+ */
static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- u64 period = __sched_period(cfs_rq->nr_running);
+ u64 slice = __sched_period(cfs_rq->nr_running);
- period *= se->load.weight;
- do_div(period, cfs_rq->load.weight);
+ slice *= se->load.weight;
+ do_div(slice, cfs_rq->load.weight);
- return period;
+ return slice;
}
-static inline void
-limit_wait_runtime(struct cfs_rq *cfs_rq, struct sched_entity *se)
+/*
+ * We calculate the vruntime slice.
+ *
+ * vs = s/w = p/rw
+ */
+static u64 __sched_vslice(unsigned long rq_weight, unsigned long nr_running)
{
- long limit = sysctl_sched_runtime_limit;
+ u64 vslice = __sched_period(nr_running);
- /*
- * Niced tasks have the same history dynamic range as
- * non-niced tasks:
- */
- if (unlikely(se->wait_runtime > limit)) {
- se->wait_runtime = limit;
- schedstat_inc(se, wait_runtime_overruns);
- schedstat_inc(cfs_rq, wait_runtime_overruns);
- }
- if (unlikely(se->wait_runtime < -limit)) {
- se->wait_runtime = -limit;
- schedstat_inc(se, wait_runtime_underruns);
- schedstat_inc(cfs_rq, wait_runtime_underruns);
- }
+ vslice *= NICE_0_LOAD;
+ do_div(vslice, rq_weight);
+
+ return vslice;
}
-static inline void
-__add_wait_runtime(struct cfs_rq *cfs_rq, struct sched_entity *se, long delta)
+static u64 sched_vslice(struct cfs_rq *cfs_rq)
{
- se->wait_runtime += delta;
- schedstat_add(se, sum_wait_runtime, delta);
- limit_wait_runtime(cfs_rq, se);
+ return __sched_vslice(cfs_rq->load.weight, cfs_rq->nr_running);
}
-static void
-add_wait_runtime(struct cfs_rq *cfs_rq, struct sched_entity *se, long delta)
+static u64 sched_vslice_add(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- schedstat_add(cfs_rq, wait_runtime, -se->wait_runtime);
- __add_wait_runtime(cfs_rq, se, delta);
- schedstat_add(cfs_rq, wait_runtime, se->wait_runtime);
+ return __sched_vslice(cfs_rq->load.weight + se->load.weight,
+ cfs_rq->nr_running + 1);
}
/*
__update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
unsigned long delta_exec)
{
- unsigned long delta, delta_fair, delta_mine, delta_exec_weighted;
- struct load_weight *lw = &cfs_rq->load;
- unsigned long load = lw->weight;
+ unsigned long delta_exec_weighted;
+ u64 vruntime;
schedstat_set(curr->exec_max, max((u64)delta_exec, curr->exec_max));
curr->sum_exec_runtime += delta_exec;
- cfs_rq->exec_clock += delta_exec;
+ schedstat_add(cfs_rq, exec_clock, delta_exec);
delta_exec_weighted = delta_exec;
if (unlikely(curr->load.weight != NICE_0_LOAD)) {
delta_exec_weighted = calc_delta_fair(delta_exec_weighted,
}
curr->vruntime += delta_exec_weighted;
- if (!sched_feat(FAIR_SLEEPERS))
- return;
-
- if (unlikely(!load))
- return;
-
- delta_fair = calc_delta_fair(delta_exec, lw);
- delta_mine = calc_delta_mine(delta_exec, curr->load.weight, lw);
-
- if (cfs_rq->sleeper_bonus > sysctl_sched_min_granularity) {
- delta = min((u64)delta_mine, cfs_rq->sleeper_bonus);
- delta = min(delta, (unsigned long)(
- (long)sysctl_sched_runtime_limit - curr->wait_runtime));
- cfs_rq->sleeper_bonus -= delta;
- delta_mine -= delta;
- }
-
- cfs_rq->fair_clock += delta_fair;
/*
- * We executed delta_exec amount of time on the CPU,
- * but we were only entitled to delta_mine amount of
- * time during that period (if nr_running == 1 then
- * the two values are equal)
- * [Note: delta_mine - delta_exec is negative]:
+ * maintain cfs_rq->min_vruntime to be a monotonic increasing
+ * value tracking the leftmost vruntime in the tree.
*/
- add_wait_runtime(cfs_rq, curr, delta_mine - delta_exec);
+ if (first_fair(cfs_rq)) {
+ vruntime = min_vruntime(curr->vruntime,
+ __pick_next_entity(cfs_rq)->vruntime);
+ } else
+ vruntime = curr->vruntime;
+
+ cfs_rq->min_vruntime =
+ max_vruntime(cfs_rq->min_vruntime, vruntime);
}
static void update_curr(struct cfs_rq *cfs_rq)
__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);
+ }
}
static inline void
update_stats_wait_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- se->wait_start_fair = cfs_rq->fair_clock;
schedstat_set(se->wait_start, rq_of(cfs_rq)->clock);
}
-static inline unsigned long
-calc_weighted(unsigned long delta, struct sched_entity *se)
-{
- unsigned long weight = se->load.weight;
-
- if (unlikely(weight != NICE_0_LOAD))
- return (u64)delta * se->load.weight >> NICE_0_SHIFT;
- else
- return delta;
-}
-
/*
* Task is being enqueued - update stats:
*/
*/
if (se != cfs_rq->curr)
update_stats_wait_start(cfs_rq, se);
- /*
- * Update the key:
- */
- se->fair_key = se->vruntime;
-}
-
-/*
- * Note: must be called with a freshly updated rq->fair_clock.
- */
-static inline void
-__update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se,
- unsigned long delta_fair)
-{
- schedstat_set(se->wait_max, max(se->wait_max,
- rq_of(cfs_rq)->clock - se->wait_start));
-
- delta_fair = calc_weighted(delta_fair, se);
-
- add_wait_runtime(cfs_rq, se, delta_fair);
}
static void
update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- unsigned long delta_fair;
-
- if (unlikely(!se->wait_start_fair))
- return;
-
- delta_fair = (unsigned long)min((u64)(2*sysctl_sched_runtime_limit),
- (u64)(cfs_rq->fair_clock - se->wait_start_fair));
-
- __update_stats_wait_end(cfs_rq, se, delta_fair);
-
- se->wait_start_fair = 0;
+ 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)
{
- update_curr(cfs_rq);
/*
* Mark the end of the wait period if dequeueing a
* waiting task:
se->exec_start = rq_of(cfs_rq)->clock;
}
-/*
- * We are descheduling a task - update its stats:
- */
-static inline void
-update_stats_curr_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
-{
- se->exec_start = 0;
-}
-
/**************************************************
* Scheduling class queueing methods:
*/
-static void __enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se,
- unsigned long delta_fair)
+static void
+account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- unsigned long load = cfs_rq->load.weight;
- long prev_runtime;
-
- /*
- * Do not boost sleepers if there's too much bonus 'in flight'
- * already:
- */
- if (unlikely(cfs_rq->sleeper_bonus > sysctl_sched_runtime_limit))
- return;
-
- if (sched_feat(SLEEPER_LOAD_AVG))
- load = rq_of(cfs_rq)->cpu_load[2];
-
- /*
- * Fix up delta_fair with the effect of us running
- * during the whole sleep period:
- */
- if (sched_feat(SLEEPER_AVG))
- delta_fair = div64_likely32((u64)delta_fair * load,
- load + se->load.weight);
-
- delta_fair = calc_weighted(delta_fair, se);
-
- prev_runtime = se->wait_runtime;
- __add_wait_runtime(cfs_rq, se, delta_fair);
- delta_fair = se->wait_runtime - prev_runtime;
+ update_load_add(&cfs_rq->load, se->load.weight);
+ cfs_rq->nr_running++;
+ se->on_rq = 1;
+}
- /*
- * Track the amount of bonus we've given to sleepers:
- */
- cfs_rq->sleeper_bonus += delta_fair;
+static void
+account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+ update_load_sub(&cfs_rq->load, se->load.weight);
+ cfs_rq->nr_running--;
+ se->on_rq = 0;
}
static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- struct task_struct *tsk = task_of(se);
- unsigned long delta_fair;
-
- if ((entity_is_task(se) && tsk->policy == SCHED_BATCH) ||
- !sched_feat(FAIR_SLEEPERS))
- return;
-
- delta_fair = (unsigned long)min((u64)(2*sysctl_sched_runtime_limit),
- (u64)(cfs_rq->fair_clock - se->sleep_start_fair));
-
- __enqueue_sleeper(cfs_rq, se, delta_fair);
-
- se->sleep_start_fair = 0;
-
#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;
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;
* 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
-enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
+place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
{
+ u64 vruntime;
+
+ vruntime = cfs_rq->min_vruntime;
+
+ if (sched_feat(TREE_AVG)) {
+ struct sched_entity *last = __pick_last_entity(cfs_rq);
+ if (last) {
+ vruntime += last->vruntime;
+ vruntime >>= 1;
+ }
+ } else if (sched_feat(APPROX_AVG) && cfs_rq->nr_running)
+ vruntime += sched_vslice(cfs_rq)/2;
+
/*
- * Update the fair clock.
+ * 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.
*/
- update_curr(cfs_rq);
+ if (initial && sched_feat(START_DEBIT))
+ vruntime += sched_vslice_add(cfs_rq, se);
- if (wakeup) {
- u64 min_runtime, latency;
+ if (!initial) {
+ /* sleeps upto a single latency don't count. */
+ if (sched_feat(NEW_FAIR_SLEEPERS))
+ vruntime -= sysctl_sched_latency;
- min_runtime = cfs_rq->min_vruntime;
- min_runtime += sysctl_sched_latency/2;
+ /* ensure we never gain time by being placed backwards. */
+ vruntime = max_vruntime(se->vruntime, vruntime);
+ }
- if (sched_feat(NEW_FAIR_SLEEPERS)) {
- latency = calc_weighted(sysctl_sched_latency, se);
- if (min_runtime > latency)
- min_runtime -= latency;
- }
+ se->vruntime = vruntime;
+}
- se->vruntime = max(se->vruntime, min_runtime);
+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);
+ if (wakeup) {
+ place_entity(cfs_rq, se, 0);
enqueue_sleeper(cfs_rq, se);
}
update_stats_enqueue(cfs_rq, se);
- __enqueue_entity(cfs_rq, se);
+ check_spread(cfs_rq, se);
+ if (se != cfs_rq->curr)
+ __enqueue_entity(cfs_rq, se);
+ account_entity_enqueue(cfs_rq, se);
}
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) {
- se->sleep_start_fair = cfs_rq->fair_clock;
#ifdef CONFIG_SCHEDSTATS
if (entity_is_task(se)) {
struct task_struct *tsk = task_of(se);
}
#endif
}
- __dequeue_entity(cfs_rq, se);
+
+ if (se != cfs_rq->curr)
+ __dequeue_entity(cfs_rq, se);
+ account_entity_dequeue(cfs_rq, se);
}
/*
* Preempt the current task with a newly woken task if needed:
*/
static void
-__check_preempt_curr_fair(struct cfs_rq *cfs_rq, struct sched_entity *curr)
+check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
{
unsigned long ideal_runtime, delta_exec;
resched_task(rq_of(cfs_rq)->curr);
}
-static inline void
+static void
set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- /*
- * 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. (note, here we rely on pick_next_task() having
- * done a put_prev_task_fair() shortly before this, which
- * updated rq->fair_clock - used by update_stats_wait_end())
- */
- update_stats_wait_end(cfs_rq, 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
* 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)->ls.load.weight >= 2*se->load.weight) {
+ 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);
}
static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq)
{
- struct sched_entity *se = __pick_next_entity(cfs_rq);
+ struct sched_entity *se = NULL;
- set_next_entity(cfs_rq, se);
+ if (first_fair(cfs_rq)) {
+ se = __pick_next_entity(cfs_rq);
+ set_next_entity(cfs_rq, se);
+ }
return se;
}
if (prev->on_rq)
update_curr(cfs_rq);
- update_stats_curr_end(cfs_rq, prev);
-
- if (prev->on_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)
+static void
+entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
{
- struct sched_entity *next;
-
/*
- * Dequeue and enqueue the task to update its
- * position within the tree:
+ * Update run-time statistics of the 'current'.
*/
- dequeue_entity(cfs_rq, curr, 0);
- enqueue_entity(cfs_rq, curr, 0);
+ update_curr(cfs_rq);
+#ifdef CONFIG_SCHED_HRTICK
/*
- * Reschedule if another task tops the current one.
+ * queued ticks are scheduled to match the slice, so don't bother
+ * validating it and just reschedule.
*/
- next = __pick_next_entity(cfs_rq);
- if (next == curr)
+ if (queued)
+ return resched_task(rq_of(cfs_rq)->curr);
+ /*
+ * 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
- __check_preempt_curr_fair(cfs_rq, curr);
+ if (cfs_rq->nr_running > 1 || !sched_feat(WAKEUP_PREEMPT))
+ check_preempt_tick(cfs_rq, curr);
}
/**************************************************
*/
static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu)
{
- /* A later patch will take group into account */
- return &cpu_rq(this_cpu)->cfs;
+ 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(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
+ list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
-/* Do the two (enqueued) tasks belong to the same group ? */
-static inline int is_same_group(struct task_struct *curr, struct task_struct *p)
+/* 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 (curr->se.cfs_rq == p->se.cfs_rq)
+ 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;
+}
+
+#define GROUP_IMBALANCE_PCT 20
+
#else /* CONFIG_FAIR_GROUP_SCHED */
#define for_each_sched_entity(se) \
#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 task_struct *curr, struct task_struct *p)
+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;
+}
+
#endif /* CONFIG_FAIR_GROUP_SCHED */
+#ifdef CONFIG_SCHED_HRTICK
+static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
+{
+ int requeue = rq->curr == 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 (!requeue)
+ delta = max(10000LL, delta);
+
+ hrtick_start(rq, delta, requeue);
+ }
+}
+#else
+static inline void
+hrtick_start_fair(struct rq *rq, struct task_struct *p)
+{
+}
+#endif
+
/*
* The enqueue_task method is called before nr_running is
* increased. Here we update the fair scheduling stats and
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;
+ struct sched_entity *se = &p->se,
+ *topse = NULL; /* Highest schedulable entity */
+ int incload = 1;
for_each_sched_entity(se) {
- if (se->on_rq)
+ topse = se;
+ if (se->on_rq) {
+ incload = 0;
break;
+ }
cfs_rq = cfs_rq_of(se);
enqueue_entity(cfs_rq, se, wakeup);
+ wakeup = 1;
}
+ /* Increment cpu load if we just enqueued the first task of a group on
+ * 'rq->cpu'. 'topse' represents the group to which task 'p' belongs
+ * at the highest grouping level.
+ */
+ if (incload)
+ inc_cpu_load(rq, topse->load.weight);
+
+ hrtick_start_fair(rq, rq->curr);
}
/*
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;
+ struct sched_entity *se = &p->se,
+ *topse = NULL; /* Highest schedulable entity */
+ int decload = 1;
for_each_sched_entity(se) {
+ topse = 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)
+ if (cfs_rq->load.weight) {
+ if (parent_entity(se))
+ decload = 0;
break;
+ }
+ sleep = 1;
}
+ /* Decrement cpu load if we just dequeued the last task of a group on
+ * 'rq->cpu'. 'topse' represents the group to which task 'p' belongs
+ * at the highest grouping level.
+ */
+ if (decload)
+ dec_cpu_load(rq, topse->load.weight);
+
+ hrtick_start_fair(rq, rq->curr);
}
/*
*
* 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 *p)
+static void yield_task_fair(struct rq *rq)
{
- struct cfs_rq *cfs_rq = task_cfs_rq(p);
- struct rb_node **link = &cfs_rq->tasks_timeline.rb_node;
- struct sched_entity *rightmost, *se = &p->se;
- struct rb_node *parent;
+ 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;
- if (likely(!sysctl_sched_compat_yield)) {
+ if (likely(!sysctl_sched_compat_yield) && curr->policy != SCHED_BATCH) {
__update_rq_clock(rq);
/*
- * Dequeue and enqueue the task to update its
- * position within the tree:
+ * Update run-time statistics of the 'current'.
*/
- dequeue_entity(cfs_rq, &p->se, 0);
- enqueue_entity(cfs_rq, &p->se, 0);
+ update_curr(cfs_rq);
return;
}
/*
* Find the rightmost entry in the rbtree:
*/
- do {
- parent = *link;
- link = &parent->rb_right;
- } while (*link);
-
- rightmost = rb_entry(parent, struct sched_entity, run_node);
+ rightmost = __pick_last_entity(cfs_rq);
/*
* Already in the rightmost position?
*/
- if (unlikely(rightmost == se))
+ if (unlikely(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->fair_key = rightmost->fair_key + 1;
+ 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.
+ *
+ * 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 (cfs_rq->rb_leftmost == &se->run_node)
- cfs_rq->rb_leftmost = rb_next(&se->run_node);
/*
- * Relink the task to the rightmost position:
+ * 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.
*/
- rb_erase(&se->run_node, &cfs_rq->tasks_timeline);
- rb_link_node(&se->run_node, parent, link);
- rb_insert_color(&se->run_node, &cfs_rq->tasks_timeline);
+ if (idle_cpu(cpu) || cpu_rq(cpu)->nr_running > 1)
+ return cpu;
+
+ for_each_domain(cpu, sd) {
+ if (sd->flags & SD_WAKE_IDLE) {
+ cpus_and(tmp, sd->span, p->cpus_allowed);
+ for_each_cpu_mask(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
+static inline int wake_idle(int cpu, struct task_struct *p)
+{
+ return cpu;
}
+#endif
+
+#ifdef CONFIG_SMP
+static int select_task_rq_fair(struct task_struct *p, int sync)
+{
+ int cpu, this_cpu;
+ struct rq *rq;
+ struct sched_domain *sd, *this_sd = NULL;
+ int new_cpu;
+
+ cpu = task_cpu(p);
+ rq = task_rq(p);
+ this_cpu = smp_processor_id();
+ new_cpu = cpu;
+
+ if (cpu == this_cpu)
+ goto out_set_cpu;
+
+ for_each_domain(this_cpu, sd) {
+ if (cpu_isset(cpu, sd->span)) {
+ this_sd = sd;
+ break;
+ }
+ }
+
+ if (unlikely(!cpu_isset(this_cpu, p->cpus_allowed)))
+ goto out_set_cpu;
+
+ /*
+ * Check for affine wakeup and passive balancing possibilities.
+ */
+ if (this_sd) {
+ int idx = this_sd->wake_idx;
+ unsigned int imbalance;
+ unsigned long load, this_load;
+
+ imbalance = 100 + (this_sd->imbalance_pct - 100) / 2;
+
+ load = source_load(cpu, idx);
+ this_load = target_load(this_cpu, idx);
+
+ new_cpu = this_cpu; /* Wake to this CPU if we can */
+
+ if (this_sd->flags & SD_WAKE_AFFINE) {
+ unsigned long tl = this_load;
+ unsigned long tl_per_task;
+
+ /*
+ * Attract cache-cold tasks on sync wakeups:
+ */
+ if (sync && !task_hot(p, rq->clock, this_sd))
+ goto out_set_cpu;
+
+ schedstat_inc(p, se.nr_wakeups_affine_attempts);
+ tl_per_task = cpu_avg_load_per_task(this_cpu);
+
+ /*
+ * If sync wakeup then subtract the (maximum possible)
+ * effect of the currently running task from the load
+ * of the current CPU:
+ */
+ if (sync)
+ tl -= current->se.load.weight;
+
+ if ((tl <= load &&
+ tl + target_load(cpu, idx) <= tl_per_task) ||
+ 100*(tl + p->se.load.weight) <= imbalance*load) {
+ /*
+ * 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);
+ goto out_set_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);
+ goto out_set_cpu;
+ }
+ }
+ }
+
+ new_cpu = cpu; /* Could not wake to this_cpu. Wake to cpu instead */
+out_set_cpu:
+ return wake_idle(new_cpu, p);
+}
+#endif /* CONFIG_SMP */
+
/*
* Preempt the current task with a newly woken task if needed:
*/
-static void check_preempt_curr_fair(struct rq *rq, struct task_struct *p)
+static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)
{
struct task_struct *curr = rq->curr;
struct cfs_rq *cfs_rq = task_cfs_rq(curr);
+ struct sched_entity *se = &curr->se, *pse = &p->se;
+ unsigned long gran;
if (unlikely(rt_prio(p->prio))) {
update_rq_clock(rq);
resched_task(curr);
return;
}
+ /*
+ * Batch tasks do not preempt (their preemption is driven by
+ * the tick):
+ */
+ if (unlikely(p->policy == SCHED_BATCH))
+ return;
+
+ if (!sched_feat(WAKEUP_PREEMPT))
+ return;
+
+ while (!is_same_group(se, pse)) {
+ se = parent_entity(se);
+ pse = parent_entity(pse);
+ }
- if (is_same_group(curr, p))
- __check_preempt_curr_fair(cfs_rq, &curr->se);
+ gran = sysctl_sched_wakeup_granularity;
+ /*
+ * More easily preempt - nice tasks, while not making
+ * it harder for + nice tasks.
+ */
+ if (unlikely(se->load.weight > NICE_0_LOAD))
+ gran = calc_delta_fair(gran, &se->load);
+
+ if (pse->vruntime + gran < se->vruntime)
+ resched_task(curr);
}
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;
cfs_rq = group_cfs_rq(se);
} while (cfs_rq);
- return task_of(se);
+ p = task_of(se);
+ hrtick_start_fair(rq, p);
+
+ return p;
}
/*
}
}
+#ifdef CONFIG_SMP
/**************************************************
* Fair scheduling class load-balancing methods:
*/
* achieve that by always pre-iterating before returning
* the current task:
*/
-static inline struct task_struct *
+static struct task_struct *
__load_balance_iterator(struct cfs_rq *cfs_rq, struct rb_node *curr)
{
struct task_struct *p;
return __load_balance_iterator(cfs_rq, cfs_rq->rb_load_balance_curr);
}
-#ifdef CONFIG_FAIR_GROUP_SCHED
-static int cfs_rq_best_prio(struct cfs_rq *cfs_rq)
-{
- struct sched_entity *curr;
- struct task_struct *p;
-
- if (!cfs_rq->nr_running)
- return MAX_PRIO;
-
- curr = __pick_next_entity(cfs_rq);
- p = task_of(curr);
-
- return p->prio;
-}
-#endif
-
static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
- unsigned long max_nr_move, unsigned long max_load_move,
+ unsigned long max_load_move,
struct sched_domain *sd, enum cpu_idle_type idle,
int *all_pinned, int *this_best_prio)
{
struct cfs_rq *busy_cfs_rq;
- unsigned long load_moved, total_nr_moved = 0, nr_moved;
long rem_load_move = max_load_move;
struct rq_iterator cfs_rq_iterator;
+ unsigned long load_moved;
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) {
#ifdef CONFIG_FAIR_GROUP_SCHED
- struct cfs_rq *this_cfs_rq;
- long imbalance;
- unsigned long maxload;
+ struct cfs_rq *this_cfs_rq = busy_cfs_rq->tg->cfs_rq[this_cpu];
+ unsigned long maxload, task_load, group_weight;
+ unsigned long thisload, per_task_load;
+ struct sched_entity *se = busy_cfs_rq->tg->se[busiest->cpu];
+
+ task_load = busy_cfs_rq->load.weight;
+ group_weight = se->load.weight;
- this_cfs_rq = cpu_cfs_rq(busy_cfs_rq, this_cpu);
+ /*
+ * 'group_weight' is contributed by tasks of total weight
+ * 'task_load'. To move 'rem_load_move' worth of weight only,
+ * we need to move a maximum task load of:
+ *
+ * maxload = (remload / group_weight) * task_load;
+ */
+ maxload = (rem_load_move * task_load) / group_weight;
- imbalance = busy_cfs_rq->load.weight - this_cfs_rq->load.weight;
- /* Don't pull if this_cfs_rq has more load than busy_cfs_rq */
- if (imbalance <= 0)
+ if (!maxload || !task_load)
continue;
- /* Don't pull more than imbalance/2 */
- imbalance /= 2;
- maxload = min(rem_load_move, imbalance);
+ per_task_load = task_load / busy_cfs_rq->nr_running;
+ /*
+ * balance_tasks will try to forcibly move atleast one task if
+ * possible (because of SCHED_LOAD_SCALE_FUZZ). Avoid that if
+ * maxload is less than GROUP_IMBALANCE_FUZZ% the per_task_load.
+ */
+ if (100 * maxload < GROUP_IMBALANCE_PCT * per_task_load)
+ continue;
- *this_best_prio = cfs_rq_best_prio(this_cfs_rq);
+ /* Disable priority-based load balance */
+ *this_best_prio = 0;
+ thisload = this_cfs_rq->load.weight;
#else
# define maxload rem_load_move
#endif
- /* pass busy_cfs_rq argument into
+ /*
+ * pass busy_cfs_rq argument into
* load_balance_[start|next]_fair iterators
*/
cfs_rq_iterator.arg = busy_cfs_rq;
- nr_moved = balance_tasks(this_rq, this_cpu, busiest,
- max_nr_move, maxload, sd, idle, all_pinned,
- &load_moved, this_best_prio, &cfs_rq_iterator);
+ load_moved = balance_tasks(this_rq, this_cpu, busiest,
+ maxload, sd, idle, all_pinned,
+ this_best_prio,
+ &cfs_rq_iterator);
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+ /*
+ * load_moved holds the task load that was moved. The
+ * effective (group) weight moved would be:
+ * load_moved_eff = load_moved/task_load * group_weight;
+ */
+ load_moved = (group_weight * load_moved) / task_load;
+
+ /* Adjust shares on both cpus to reflect load_moved */
+ group_weight -= load_moved;
+ set_se_shares(se, group_weight);
+
+ se = busy_cfs_rq->tg->se[this_cpu];
+ if (!thisload)
+ group_weight = load_moved;
+ else
+ group_weight = se->load.weight + load_moved;
+ set_se_shares(se, group_weight);
+#endif
- total_nr_moved += nr_moved;
- max_nr_move -= nr_moved;
rem_load_move -= load_moved;
- if (max_nr_move <= 0 || rem_load_move <= 0)
+ if (rem_load_move <= 0)
break;
}
return max_load_move - rem_load_move;
}
+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
+
/*
* scheduler tick hitting a task of our scheduling class:
*/
-static void task_tick_fair(struct rq *rq, struct task_struct *curr)
+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);
+ entity_tick(cfs_rq, se, queued);
}
}
-#define swap(a,b) do { typeof(a) tmp = (a); (a) = (b); (b) = tmp; } while (0)
+#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
{
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);
- se->vruntime = cfs_rq->min_vruntime;
- update_stats_enqueue(cfs_rq, se);
+ 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);
+ }
+
+ enqueue_task_fair(rq, p, 0);
+ resched_task(rq->curr);
+}
+
+/*
+ * 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)
+{
/*
- * The first wait is dominated by the child-runs-first logic,
- * so do not credit it with that waiting time yet:
+ * 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 (sched_feat(SKIP_INITIAL))
- se->wait_start_fair = 0;
+ if (running) {
+ if (p->prio > oldprio)
+ resched_task(rq->curr);
+ } else
+ check_preempt_curr(rq, p);
+}
+/*
+ * We switched to the sched_fair class.
+ */
+static void switched_to_fair(struct rq *rq, struct task_struct *p,
+ int running)
+{
/*
- * The statistical average of wait_runtime is about
- * -granularity/2, so initialize the task with that:
+ * 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 (sched_feat(START_DEBIT))
- se->wait_runtime = -(__sched_period(cfs_rq->nr_running+1) / 2);
-
- if (sysctl_sched_child_runs_first &&
- curr->vruntime < se->vruntime) {
-
- dequeue_entity(cfs_rq, curr, 0);
- swap(curr->vruntime, se->vruntime);
- enqueue_entity(cfs_rq, curr, 0);
- }
-
- update_stats_enqueue(cfs_rq, se);
- __enqueue_entity(cfs_rq, se);
- resched_task(rq->curr);
+ if (running)
+ resched_task(rq->curr);
+ else
+ check_preempt_curr(rq, p);
}
-#ifdef CONFIG_FAIR_GROUP_SCHED
/* Account for a task changing its policy or group.
*
* This routine is mostly called to set cfs_rq->curr field when a task
for_each_sched_entity(se)
set_next_entity(cfs_rq_of(se), se);
}
-#else
-static void set_curr_task_fair(struct rq *rq)
-{
-}
-#endif
/*
* All the scheduling class methods:
*/
-struct sched_class fair_sched_class __read_mostly = {
+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,
+#ifdef CONFIG_SMP
+ .select_task_rq = select_task_rq_fair,
+#endif /* CONFIG_SMP */
- .check_preempt_curr = check_preempt_curr_fair,
+ .check_preempt_curr = check_preempt_wakeup,
.pick_next_task = pick_next_task_fair,
.put_prev_task = put_prev_task_fair,
+#ifdef CONFIG_SMP
.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_SCHED_DEBUG
{
struct cfs_rq *cfs_rq;
+#ifdef CONFIG_FAIR_GROUP_SCHED
+ print_cfs_rq(m, cpu, &cpu_rq(cpu)->cfs);
+#endif
+ rcu_read_lock();
for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
print_cfs_rq(m, cpu, cfs_rq);
+ rcu_read_unlock();
}
#endif
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff