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-rw-r--r--kernel/sched.c152
1 files changed, 31 insertions, 121 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index bc38804e40ddf7..12d291bf3379a3 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -215,7 +215,6 @@ struct runqueue {
*/
unsigned long nr_running;
#ifdef CONFIG_SMP
- unsigned long prio_bias;
unsigned long cpu_load[3];
#endif
unsigned long long nr_switches;
@@ -669,68 +668,13 @@ static int effective_prio(task_t *p)
return prio;
}
-#ifdef CONFIG_SMP
-static inline void inc_prio_bias(runqueue_t *rq, int prio)
-{
- rq->prio_bias += MAX_PRIO - prio;
-}
-
-static inline void dec_prio_bias(runqueue_t *rq, int prio)
-{
- rq->prio_bias -= MAX_PRIO - prio;
-}
-
-static inline void inc_nr_running(task_t *p, runqueue_t *rq)
-{
- rq->nr_running++;
- if (rt_task(p)) {
- if (p != rq->migration_thread)
- /*
- * The migration thread does the actual balancing. Do
- * not bias by its priority as the ultra high priority
- * will skew balancing adversely.
- */
- inc_prio_bias(rq, p->prio);
- } else
- inc_prio_bias(rq, p->static_prio);
-}
-
-static inline void dec_nr_running(task_t *p, runqueue_t *rq)
-{
- rq->nr_running--;
- if (rt_task(p)) {
- if (p != rq->migration_thread)
- dec_prio_bias(rq, p->prio);
- } else
- dec_prio_bias(rq, p->static_prio);
-}
-#else
-static inline void inc_prio_bias(runqueue_t *rq, int prio)
-{
-}
-
-static inline void dec_prio_bias(runqueue_t *rq, int prio)
-{
-}
-
-static inline void inc_nr_running(task_t *p, runqueue_t *rq)
-{
- rq->nr_running++;
-}
-
-static inline void dec_nr_running(task_t *p, runqueue_t *rq)
-{
- rq->nr_running--;
-}
-#endif
-
/*
* __activate_task - move a task to the runqueue.
*/
static inline void __activate_task(task_t *p, runqueue_t *rq)
{
enqueue_task(p, rq->active);
- inc_nr_running(p, rq);
+ rq->nr_running++;
}
/*
@@ -739,7 +683,7 @@ static inline void __activate_task(task_t *p, runqueue_t *rq)
static inline void __activate_idle_task(task_t *p, runqueue_t *rq)
{
enqueue_task_head(p, rq->active);
- inc_nr_running(p, rq);
+ rq->nr_running++;
}
static int recalc_task_prio(task_t *p, unsigned long long now)
@@ -863,7 +807,7 @@ static void activate_task(task_t *p, runqueue_t *rq, int local)
*/
static void deactivate_task(struct task_struct *p, runqueue_t *rq)
{
- dec_nr_running(p, rq);
+ rq->nr_running--;
dequeue_task(p, p->array);
p->array = NULL;
}
@@ -1007,61 +951,27 @@ void kick_process(task_t *p)
* We want to under-estimate the load of migration sources, to
* balance conservatively.
*/
-static unsigned long __source_load(int cpu, int type, enum idle_type idle)
+static inline unsigned long source_load(int cpu, int type)
{
runqueue_t *rq = cpu_rq(cpu);
- unsigned long running = rq->nr_running;
- unsigned long source_load, cpu_load = rq->cpu_load[type-1],
- load_now = running * SCHED_LOAD_SCALE;
-
+ unsigned long load_now = rq->nr_running * SCHED_LOAD_SCALE;
if (type == 0)
- source_load = load_now;
- else
- source_load = min(cpu_load, load_now);
-
- if (running > 1 || (idle == NOT_IDLE && running))
- /*
- * If we are busy rebalancing the load is biased by
- * priority to create 'nice' support across cpus. When
- * idle rebalancing we should only bias the source_load if
- * there is more than one task running on that queue to
- * prevent idle rebalance from trying to pull tasks from a
- * queue with only one running task.
- */
- source_load = source_load * rq->prio_bias / running;
-
- return source_load;
-}
+ return load_now;
-static inline unsigned long source_load(int cpu, int type)
-{
- return __source_load(cpu, type, NOT_IDLE);
+ return min(rq->cpu_load[type-1], load_now);
}
/*
* Return a high guess at the load of a migration-target cpu
*/
-static inline unsigned long __target_load(int cpu, int type, enum idle_type idle)
+static inline unsigned long target_load(int cpu, int type)
{
runqueue_t *rq = cpu_rq(cpu);
- unsigned long running = rq->nr_running;
- unsigned long target_load, cpu_load = rq->cpu_load[type-1],
- load_now = running * SCHED_LOAD_SCALE;
-
+ unsigned long load_now = rq->nr_running * SCHED_LOAD_SCALE;
if (type == 0)
- target_load = load_now;
- else
- target_load = max(cpu_load, load_now);
-
- if (running > 1 || (idle == NOT_IDLE && running))
- target_load = target_load * rq->prio_bias / running;
-
- return target_load;
-}
+ return load_now;
-static inline unsigned long target_load(int cpu, int type)
-{
- return __target_load(cpu, type, NOT_IDLE);
+ return max(rq->cpu_load[type-1], load_now);
}
/*
@@ -1294,9 +1204,6 @@ static int try_to_wake_up(task_t *p, unsigned int state, int sync)
}
}
- if (p->last_waker_cpu != this_cpu)
- goto out_set_cpu;
-
if (unlikely(!cpu_isset(this_cpu, p->cpus_allowed)))
goto out_set_cpu;
@@ -1367,8 +1274,6 @@ out_set_cpu:
cpu = task_cpu(p);
}
- p->last_waker_cpu = this_cpu;
-
out_activate:
#endif /* CONFIG_SMP */
if (old_state == TASK_UNINTERRUPTIBLE) {
@@ -1450,12 +1355,9 @@ void fastcall sched_fork(task_t *p, int clone_flags)
#ifdef CONFIG_SCHEDSTATS
memset(&p->sched_info, 0, sizeof(p->sched_info));
#endif
-#if defined(CONFIG_SMP)
- p->last_waker_cpu = cpu;
-#if defined(__ARCH_WANT_UNLOCKED_CTXSW)
+#if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW)
p->oncpu = 0;
#endif
-#endif
#ifdef CONFIG_PREEMPT
/* Want to start with kernel preemption disabled. */
task_thread_info(p)->preempt_count = 1;
@@ -1530,7 +1432,7 @@ void fastcall wake_up_new_task(task_t *p, unsigned long clone_flags)
list_add_tail(&p->run_list, &current->run_list);
p->array = current->array;
p->array->nr_active++;
- inc_nr_running(p, rq);
+ rq->nr_running++;
}
set_need_resched();
} else
@@ -1875,9 +1777,9 @@ void pull_task(runqueue_t *src_rq, prio_array_t *src_array, task_t *p,
runqueue_t *this_rq, prio_array_t *this_array, int this_cpu)
{
dequeue_task(p, src_array);
- dec_nr_running(p, src_rq);
+ src_rq->nr_running--;
set_task_cpu(p, this_cpu);
- inc_nr_running(p, this_rq);
+ this_rq->nr_running++;
enqueue_task(p, this_array);
p->timestamp = (p->timestamp - src_rq->timestamp_last_tick)
+ this_rq->timestamp_last_tick;
@@ -2056,9 +1958,9 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
/* Bias balancing toward cpus of our domain */
if (local_group)
- load = __target_load(i, load_idx, idle);
+ load = target_load(i, load_idx);
else
- load = __source_load(i, load_idx, idle);
+ load = source_load(i, load_idx);
avg_load += load;
}
@@ -2171,7 +2073,7 @@ static runqueue_t *find_busiest_queue(struct sched_group *group,
int i;
for_each_cpu_mask(i, group->cpumask) {
- load = __source_load(i, 0, idle);
+ load = source_load(i, 0);
if (load > max_load) {
max_load = load;
@@ -3571,10 +3473,8 @@ void set_user_nice(task_t *p, long nice)
goto out_unlock;
}
array = p->array;
- if (array) {
+ if (array)
dequeue_task(p, array);
- dec_prio_bias(rq, p->static_prio);
- }
old_prio = p->prio;
new_prio = NICE_TO_PRIO(nice);
@@ -3584,7 +3484,6 @@ void set_user_nice(task_t *p, long nice)
if (array) {
enqueue_task(p, array);
- inc_prio_bias(rq, p->static_prio);
/*
* If the task increased its priority or is running and
* lowered its priority, then reschedule its CPU:
@@ -5159,7 +5058,18 @@ static void init_sched_build_groups(struct sched_group groups[], cpumask_t span,
#define MAX_DOMAIN_DISTANCE 32
static unsigned long long migration_cost[MAX_DOMAIN_DISTANCE] =
- { [ 0 ... MAX_DOMAIN_DISTANCE-1 ] = -1LL };
+ { [ 0 ... MAX_DOMAIN_DISTANCE-1 ] =
+/*
+ * Architectures may override the migration cost and thus avoid
+ * boot-time calibration. Unit is nanoseconds. Mostly useful for
+ * virtualized hardware:
+ */
+#ifdef CONFIG_DEFAULT_MIGRATION_COST
+ CONFIG_DEFAULT_MIGRATION_COST
+#else
+ -1LL
+#endif
+};
/*
* Allow override of migration cost - in units of microseconds.
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-14 06:40:23 +0000