diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched.c | 101 |
1 files changed, 83 insertions, 18 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 3ce26954be12..c6827f94e156 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -206,6 +206,7 @@ struct runqueue { */ unsigned long nr_running; #ifdef CONFIG_SMP + unsigned long prio_bias; unsigned long cpu_load[3]; #endif unsigned long long nr_switches; @@ -659,13 +660,45 @@ static int effective_prio(task_t *p) return prio; } +#ifdef CONFIG_SMP +static inline void inc_prio_bias(runqueue_t *rq, int static_prio) +{ + rq->prio_bias += MAX_PRIO - static_prio; +} + +static inline void dec_prio_bias(runqueue_t *rq, int static_prio) +{ + rq->prio_bias -= MAX_PRIO - static_prio; +} +#else +static inline void inc_prio_bias(runqueue_t *rq, int static_prio) +{ +} + +static inline void dec_prio_bias(runqueue_t *rq, int static_prio) +{ +} +#endif + +static inline void inc_nr_running(task_t *p, runqueue_t *rq) +{ + rq->nr_running++; + inc_prio_bias(rq, p->static_prio); +} + +static inline void dec_nr_running(task_t *p, runqueue_t *rq) +{ + rq->nr_running--; + dec_prio_bias(rq, p->static_prio); +} + /* * __activate_task - move a task to the runqueue. */ static inline void __activate_task(task_t *p, runqueue_t *rq) { enqueue_task(p, rq->active); - rq->nr_running++; + inc_nr_running(p, rq); } /* @@ -674,7 +707,7 @@ 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); - rq->nr_running++; + inc_nr_running(p, rq); } static int recalc_task_prio(task_t *p, unsigned long long now) @@ -793,7 +826,7 @@ static void activate_task(task_t *p, runqueue_t *rq, int local) */ static void deactivate_task(struct task_struct *p, runqueue_t *rq) { - rq->nr_running--; + dec_nr_running(p, rq); dequeue_task(p, p->array); p->array = NULL; } @@ -930,27 +963,54 @@ void kick_process(task_t *p) * We want to under-estimate the load of migration sources, to * balance conservatively. */ -static inline unsigned long source_load(int cpu, int type) +static inline unsigned long __source_load(int cpu, int type, enum idle_type idle) { runqueue_t *rq = cpu_rq(cpu); - unsigned long load_now = rq->nr_running * SCHED_LOAD_SCALE; + unsigned long cpu_load = rq->cpu_load[type-1], + load_now = rq->nr_running * SCHED_LOAD_SCALE; + + if (idle == NOT_IDLE) { + /* + * If we are balancing busy runqueues the load is biased by + * priority to create 'nice' support across cpus. + */ + cpu_load *= rq->prio_bias; + load_now *= rq->prio_bias; + } + if (type == 0) return load_now; - return min(rq->cpu_load[type-1], load_now); + return min(cpu_load, load_now); +} + +static inline unsigned long source_load(int cpu, int type) +{ + return __source_load(cpu, type, NOT_IDLE); } /* * Return a high guess at the load of a migration-target cpu */ -static inline unsigned long target_load(int cpu, int type) +static inline unsigned long __target_load(int cpu, int type, enum idle_type idle) { runqueue_t *rq = cpu_rq(cpu); - unsigned long load_now = rq->nr_running * SCHED_LOAD_SCALE; + unsigned long cpu_load = rq->cpu_load[type-1], + load_now = rq->nr_running * SCHED_LOAD_SCALE; + if (type == 0) return load_now; - return max(rq->cpu_load[type-1], load_now); + if (idle == NOT_IDLE) { + cpu_load *= rq->prio_bias; + load_now *= rq->prio_bias; + } + return max(cpu_load, load_now); +} + +static inline unsigned long target_load(int cpu, int type) +{ + return __target_load(cpu, type, NOT_IDLE); } /* @@ -1411,7 +1471,7 @@ 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++; - rq->nr_running++; + inc_nr_running(p, rq); } set_need_resched(); } else @@ -1756,9 +1816,9 @@ 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); - src_rq->nr_running--; + dec_nr_running(p, src_rq); set_task_cpu(p, this_cpu); - this_rq->nr_running++; + inc_nr_running(p, this_rq); enqueue_task(p, this_array); p->timestamp = (p->timestamp - src_rq->timestamp_last_tick) + this_rq->timestamp_last_tick; @@ -1937,9 +1997,9 @@ 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); + load = __target_load(i, load_idx, idle); else - load = source_load(i, load_idx); + load = __source_load(i, load_idx, idle); avg_load += load; } @@ -2044,14 +2104,15 @@ out_balanced: /* * find_busiest_queue - find the busiest runqueue among the cpus in group. */ -static runqueue_t *find_busiest_queue(struct sched_group *group) +static runqueue_t *find_busiest_queue(struct sched_group *group, + enum idle_type idle) { unsigned long load, max_load = 0; runqueue_t *busiest = NULL; int i; for_each_cpu_mask(i, group->cpumask) { - load = source_load(i, 0); + load = __source_load(i, 0, idle); if (load > max_load) { max_load = load; @@ -2095,7 +2156,7 @@ static int load_balance(int this_cpu, runqueue_t *this_rq, goto out_balanced; } - busiest = find_busiest_queue(group); + busiest = find_busiest_queue(group, idle); if (!busiest) { schedstat_inc(sd, lb_nobusyq[idle]); goto out_balanced; @@ -2218,7 +2279,7 @@ static int load_balance_newidle(int this_cpu, runqueue_t *this_rq, goto out_balanced; } - busiest = find_busiest_queue(group); + busiest = find_busiest_queue(group, NEWLY_IDLE); if (!busiest) { schedstat_inc(sd, lb_nobusyq[NEWLY_IDLE]); goto out_balanced; @@ -3447,7 +3508,9 @@ void set_user_nice(task_t *p, long nice) * not SCHED_NORMAL: */ if (rt_task(p)) { + dec_prio_bias(rq, p->static_prio); p->static_prio = NICE_TO_PRIO(nice); + inc_prio_bias(rq, p->static_prio); goto out_unlock; } array = p->array; @@ -3457,7 +3520,9 @@ void set_user_nice(task_t *p, long nice) old_prio = p->prio; new_prio = NICE_TO_PRIO(nice); delta = new_prio - old_prio; + dec_prio_bias(rq, p->static_prio); p->static_prio = NICE_TO_PRIO(nice); + inc_prio_bias(rq, p->static_prio); p->prio += delta; if (array) { |