diff options
Diffstat (limited to 'kernel/sched.c')
-rw-r--r-- | kernel/sched.c | 129 |
1 files changed, 18 insertions, 111 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index bc38804e40dd..87d93be336a1 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 load_now; - return source_load; -} - -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); + return load_now; - if (running > 1 || (idle == NOT_IDLE && running)) - target_load = target_load * rq->prio_bias / running; - - return target_load; -} - -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); } /* @@ -1530,7 +1440,7 @@ void fastcall wake_up_new_task(task_t *p, unsigned long clone_flags) list_add_tail(&p->run_list, ¤t->run_list); p->array = current->array; p->array->nr_active++; - inc_nr_running(p, rq); + rq->nr_running++; } set_need_resched(); } else @@ -1875,9 +1785,9 @@ 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 +1966,9 @@ 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 +2081,7 @@ 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 +3481,8 @@ 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 +3492,6 @@ 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: |