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-rw-r--r--kernel/sched.c155
1 files changed, 1 insertions, 154 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 5f102e6c7a4..a4ca632c477 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3006,23 +3006,6 @@ static inline void idle_balance(int cpu, struct rq *rq)
}
#endif
-static inline void wake_priority_sleeper(struct rq *rq)
-{
-#ifdef CONFIG_SCHED_SMT
- if (!rq->nr_running)
- return;
-
- spin_lock(&rq->lock);
- /*
- * If an SMT sibling task has been put to sleep for priority
- * reasons reschedule the idle task to see if it can now run.
- */
- if (rq->nr_running)
- resched_task(rq->idle);
- spin_unlock(&rq->lock);
-#endif
-}
-
DEFINE_PER_CPU(struct kernel_stat, kstat);
EXPORT_PER_CPU_SYMBOL(kstat);
@@ -3239,10 +3222,7 @@ void scheduler_tick(void)
update_cpu_clock(p, rq, now);
- if (p == rq->idle)
- /* Task on the idle queue */
- wake_priority_sleeper(rq);
- else
+ if (p != rq->idle)
task_running_tick(rq, p);
#ifdef CONFIG_SMP
update_load(rq);
@@ -3251,136 +3231,6 @@ void scheduler_tick(void)
#endif
}
-#ifdef CONFIG_SCHED_SMT
-static inline void wakeup_busy_runqueue(struct rq *rq)
-{
- /* If an SMT runqueue is sleeping due to priority reasons wake it up */
- if (rq->curr == rq->idle && rq->nr_running)
- resched_task(rq->idle);
-}
-
-/*
- * Called with interrupt disabled and this_rq's runqueue locked.
- */
-static void wake_sleeping_dependent(int this_cpu)
-{
- struct sched_domain *tmp, *sd = NULL;
- int i;
-
- for_each_domain(this_cpu, tmp) {
- if (tmp->flags & SD_SHARE_CPUPOWER) {
- sd = tmp;
- break;
- }
- }
-
- if (!sd)
- return;
-
- for_each_cpu_mask(i, sd->span) {
- struct rq *smt_rq = cpu_rq(i);
-
- if (i == this_cpu)
- continue;
- if (unlikely(!spin_trylock(&smt_rq->lock)))
- continue;
-
- wakeup_busy_runqueue(smt_rq);
- spin_unlock(&smt_rq->lock);
- }
-}
-
-/*
- * number of 'lost' timeslices this task wont be able to fully
- * utilize, if another task runs on a sibling. This models the
- * slowdown effect of other tasks running on siblings:
- */
-static inline unsigned long
-smt_slice(struct task_struct *p, struct sched_domain *sd)
-{
- return p->time_slice * (100 - sd->per_cpu_gain) / 100;
-}
-
-/*
- * To minimise lock contention and not have to drop this_rq's runlock we only
- * trylock the sibling runqueues and bypass those runqueues if we fail to
- * acquire their lock. As we only trylock the normal locking order does not
- * need to be obeyed.
- */
-static int
-dependent_sleeper(int this_cpu, struct rq *this_rq, struct task_struct *p)
-{
- struct sched_domain *tmp, *sd = NULL;
- int ret = 0, i;
-
- /* kernel/rt threads do not participate in dependent sleeping */
- if (!p->mm || rt_task(p))
- return 0;
-
- for_each_domain(this_cpu, tmp) {
- if (tmp->flags & SD_SHARE_CPUPOWER) {
- sd = tmp;
- break;
- }
- }
-
- if (!sd)
- return 0;
-
- for_each_cpu_mask(i, sd->span) {
- struct task_struct *smt_curr;
- struct rq *smt_rq;
-
- if (i == this_cpu)
- continue;
-
- smt_rq = cpu_rq(i);
- if (unlikely(!spin_trylock(&smt_rq->lock)))
- continue;
-
- smt_curr = smt_rq->curr;
-
- if (!smt_curr->mm)
- goto unlock;
-
- /*
- * If a user task with lower static priority than the
- * running task on the SMT sibling is trying to schedule,
- * delay it till there is proportionately less timeslice
- * left of the sibling task to prevent a lower priority
- * task from using an unfair proportion of the
- * physical cpu's resources. -ck
- */
- if (rt_task(smt_curr)) {
- /*
- * With real time tasks we run non-rt tasks only
- * per_cpu_gain% of the time.
- */
- if ((jiffies % DEF_TIMESLICE) >
- (sd->per_cpu_gain * DEF_TIMESLICE / 100))
- ret = 1;
- } else {
- if (smt_curr->static_prio < p->static_prio &&
- !TASK_PREEMPTS_CURR(p, smt_rq) &&
- smt_slice(smt_curr, sd) > task_timeslice(p))
- ret = 1;
- }
-unlock:
- spin_unlock(&smt_rq->lock);
- }
- return ret;
-}
-#else
-static inline void wake_sleeping_dependent(int this_cpu)
-{
-}
-static inline int
-dependent_sleeper(int this_cpu, struct rq *this_rq, struct task_struct *p)
-{
- return 0;
-}
-#endif
-
#if defined(CONFIG_PREEMPT) && defined(CONFIG_DEBUG_PREEMPT)
void fastcall add_preempt_count(int val)
@@ -3507,7 +3357,6 @@ need_resched_nonpreemptible:
if (!rq->nr_running) {
next = rq->idle;
rq->expired_timestamp = 0;
- wake_sleeping_dependent(cpu);
goto switch_tasks;
}
}
@@ -3547,8 +3396,6 @@ need_resched_nonpreemptible:
}
}
next->sleep_type = SLEEP_NORMAL;
- if (rq->nr_running == 1 && dependent_sleeper(cpu, rq, next))
- next = rq->idle;
switch_tasks:
if (next == rq->idle)
schedstat_inc(rq, sched_goidle);