diff options
| -rw-r--r-- | kernel/sched.c | 65 |
1 files changed, 47 insertions, 18 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 15db82116e19..ef748e691608 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2580,6 +2580,13 @@ out: } #ifdef CONFIG_SCHED_SMT +static inline void wakeup_busy_runqueue(runqueue_t *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); +} + static inline void wake_sleeping_dependent(int this_cpu, runqueue_t *this_rq) { struct sched_domain *tmp, *sd = NULL; @@ -2613,12 +2620,7 @@ static inline void wake_sleeping_dependent(int this_cpu, runqueue_t *this_rq) for_each_cpu_mask(i, sibling_map) { runqueue_t *smt_rq = cpu_rq(i); - /* - * If an SMT sibling task is sleeping due to priority - * reasons wake it up now. - */ - if (smt_rq->curr == smt_rq->idle && smt_rq->nr_running) - resched_task(smt_rq->idle); + wakeup_busy_runqueue(smt_rq); } for_each_cpu_mask(i, sibling_map) @@ -2672,6 +2674,10 @@ static inline int dependent_sleeper(int this_cpu, runqueue_t *this_rq) runqueue_t *smt_rq = cpu_rq(i); task_t *smt_curr = smt_rq->curr; + /* Kernel threads do not participate in dependent sleeping */ + if (!p->mm || !smt_curr->mm || rt_task(p)) + goto check_smt_task; + /* * If a user task with lower static priority than the * running task on the SMT sibling is trying to schedule, @@ -2680,21 +2686,44 @@ static inline int dependent_sleeper(int this_cpu, runqueue_t *this_rq) * task from using an unfair proportion of the * physical cpu's resources. -ck */ - if (((smt_curr->time_slice * (100 - sd->per_cpu_gain) / 100) > - task_timeslice(p) || rt_task(smt_curr)) && - p->mm && smt_curr->mm && !rt_task(p)) - ret = 1; + 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->time_slice * (100 - sd->per_cpu_gain) / + 100) > task_timeslice(p))) + ret = 1; + +check_smt_task: + if ((!smt_curr->mm && smt_curr != smt_rq->idle) || + rt_task(smt_curr)) + continue; + if (!p->mm) { + wakeup_busy_runqueue(smt_rq); + continue; + } /* - * Reschedule a lower priority task on the SMT sibling, - * or wake it up if it has been put to sleep for priority - * reasons. + * Reschedule a lower priority task on the SMT sibling for + * it to be put to sleep, or wake it up if it has been put to + * sleep for priority reasons to see if it should run now. */ - if ((((p->time_slice * (100 - sd->per_cpu_gain) / 100) > - task_timeslice(smt_curr) || rt_task(p)) && - smt_curr->mm && p->mm && !rt_task(smt_curr)) || - (smt_curr == smt_rq->idle && smt_rq->nr_running)) - resched_task(smt_curr); + if (rt_task(p)) { + if ((jiffies % DEF_TIMESLICE) > + (sd->per_cpu_gain * DEF_TIMESLICE / 100)) + resched_task(smt_curr); + } else { + if ((p->time_slice * (100 - sd->per_cpu_gain) / 100) > + task_timeslice(smt_curr)) + resched_task(smt_curr); + else + wakeup_busy_runqueue(smt_rq); + } } out_unlock: for_each_cpu_mask(i, sibling_map) |