diff options
Diffstat (limited to 'kernel/sched.c')
-rw-r--r-- | kernel/sched.c | 155 |
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); |