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-rw-r--r--kernel/sched.c129
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 {
215 */ 215 */
216 unsigned long nr_running; 216 unsigned long nr_running;
217#ifdef CONFIG_SMP 217#ifdef CONFIG_SMP
218 unsigned long prio_bias;
219 unsigned long cpu_load[3]; 218 unsigned long cpu_load[3];
220#endif 219#endif
221 unsigned long long nr_switches; 220 unsigned long long nr_switches;
@@ -669,68 +668,13 @@ static int effective_prio(task_t *p)
669 return prio; 668 return prio;
670} 669}
671 670
672#ifdef CONFIG_SMP
673static inline void inc_prio_bias(runqueue_t *rq, int prio)
674{
675 rq->prio_bias += MAX_PRIO - prio;
676}
677
678static inline void dec_prio_bias(runqueue_t *rq, int prio)
679{
680 rq->prio_bias -= MAX_PRIO - prio;
681}
682
683static inline void inc_nr_running(task_t *p, runqueue_t *rq)
684{
685 rq->nr_running++;
686 if (rt_task(p)) {
687 if (p != rq->migration_thread)
688 /*
689 * The migration thread does the actual balancing. Do
690 * not bias by its priority as the ultra high priority
691 * will skew balancing adversely.
692 */
693 inc_prio_bias(rq, p->prio);
694 } else
695 inc_prio_bias(rq, p->static_prio);
696}
697
698static inline void dec_nr_running(task_t *p, runqueue_t *rq)
699{
700 rq->nr_running--;
701 if (rt_task(p)) {
702 if (p != rq->migration_thread)
703 dec_prio_bias(rq, p->prio);
704 } else
705 dec_prio_bias(rq, p->static_prio);
706}
707#else
708static inline void inc_prio_bias(runqueue_t *rq, int prio)
709{
710}
711
712static inline void dec_prio_bias(runqueue_t *rq, int prio)
713{
714}
715
716static inline void inc_nr_running(task_t *p, runqueue_t *rq)
717{
718 rq->nr_running++;
719}
720
721static inline void dec_nr_running(task_t *p, runqueue_t *rq)
722{
723 rq->nr_running--;
724}
725#endif
726
727/* 671/*
728 * __activate_task - move a task to the runqueue. 672 * __activate_task - move a task to the runqueue.
729 */ 673 */
730static inline void __activate_task(task_t *p, runqueue_t *rq) 674static inline void __activate_task(task_t *p, runqueue_t *rq)
731{ 675{
732 enqueue_task(p, rq->active); 676 enqueue_task(p, rq->active);
733 inc_nr_running(p, rq); 677 rq->nr_running++;
734} 678}
735 679
736/* 680/*
@@ -739,7 +683,7 @@ static inline void __activate_task(task_t *p, runqueue_t *rq)
739static inline void __activate_idle_task(task_t *p, runqueue_t *rq) 683static inline void __activate_idle_task(task_t *p, runqueue_t *rq)
740{ 684{
741 enqueue_task_head(p, rq->active); 685 enqueue_task_head(p, rq->active);
742 inc_nr_running(p, rq); 686 rq->nr_running++;
743} 687}
744 688
745static int recalc_task_prio(task_t *p, unsigned long long now) 689static 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)
863 */ 807 */
864static void deactivate_task(struct task_struct *p, runqueue_t *rq) 808static void deactivate_task(struct task_struct *p, runqueue_t *rq)
865{ 809{
866 dec_nr_running(p, rq); 810 rq->nr_running--;
867 dequeue_task(p, p->array); 811 dequeue_task(p, p->array);
868 p->array = NULL; 812 p->array = NULL;
869} 813}
@@ -1007,61 +951,27 @@ void kick_process(task_t *p)
1007 * We want to under-estimate the load of migration sources, to 951 * We want to under-estimate the load of migration sources, to
1008 * balance conservatively. 952 * balance conservatively.
1009 */ 953 */
1010static unsigned long __source_load(int cpu, int type, enum idle_type idle) 954static inline unsigned long source_load(int cpu, int type)
1011{ 955{
1012 runqueue_t *rq = cpu_rq(cpu); 956 runqueue_t *rq = cpu_rq(cpu);
1013 unsigned long running = rq->nr_running; 957 unsigned long load_now = rq->nr_running * SCHED_LOAD_SCALE;
1014 unsigned long source_load, cpu_load = rq->cpu_load[type-1],
1015 load_now = running * SCHED_LOAD_SCALE;
1016
1017 if (type == 0) 958 if (type == 0)
1018 source_load = load_now; 959 return load_now;
1019 else
1020 source_load = min(cpu_load, load_now);
1021
1022 if (running > 1 || (idle == NOT_IDLE && running))
1023 /*
1024 * If we are busy rebalancing the load is biased by
1025 * priority to create 'nice' support across cpus. When
1026 * idle rebalancing we should only bias the source_load if
1027 * there is more than one task running on that queue to
1028 * prevent idle rebalance from trying to pull tasks from a
1029 * queue with only one running task.
1030 */
1031 source_load = source_load * rq->prio_bias / running;
1032 960
1033 return source_load; 961 return min(rq->cpu_load[type-1], load_now);
1034}
1035
1036static inline unsigned long source_load(int cpu, int type)
1037{
1038 return __source_load(cpu, type, NOT_IDLE);
1039} 962}
1040 963
1041/* 964/*
1042 * Return a high guess at the load of a migration-target cpu 965 * Return a high guess at the load of a migration-target cpu
1043 */ 966 */
1044static inline unsigned long __target_load(int cpu, int type, enum idle_type idle) 967static inline unsigned long target_load(int cpu, int type)
1045{ 968{
1046 runqueue_t *rq = cpu_rq(cpu); 969 runqueue_t *rq = cpu_rq(cpu);
1047 unsigned long running = rq->nr_running; 970 unsigned long load_now = rq->nr_running * SCHED_LOAD_SCALE;
1048 unsigned long target_load, cpu_load = rq->cpu_load[type-1],
1049 load_now = running * SCHED_LOAD_SCALE;
1050
1051 if (type == 0) 971 if (type == 0)
1052 target_load = load_now; 972 return load_now;
1053 else
1054 target_load = max(cpu_load, load_now);
1055 973
1056 if (running > 1 || (idle == NOT_IDLE && running)) 974 return max(rq->cpu_load[type-1], load_now);
1057 target_load = target_load * rq->prio_bias / running;
1058
1059 return target_load;
1060}
1061
1062static inline unsigned long target_load(int cpu, int type)
1063{
1064 return __target_load(cpu, type, NOT_IDLE);
1065} 975}
1066 976
1067/* 977/*
@@ -1530,7 +1440,7 @@ void fastcall wake_up_new_task(task_t *p, unsigned long clone_flags)
1530 list_add_tail(&p->run_list, &current->run_list); 1440 list_add_tail(&p->run_list, &current->run_list);
1531 p->array = current->array; 1441 p->array = current->array;
1532 p->array->nr_active++; 1442 p->array->nr_active++;
1533 inc_nr_running(p, rq); 1443 rq->nr_running++;
1534 } 1444 }
1535 set_need_resched(); 1445 set_need_resched();
1536 } else 1446 } else
@@ -1875,9 +1785,9 @@ void pull_task(runqueue_t *src_rq, prio_array_t *src_array, task_t *p,
1875 runqueue_t *this_rq, prio_array_t *this_array, int this_cpu) 1785 runqueue_t *this_rq, prio_array_t *this_array, int this_cpu)
1876{ 1786{
1877 dequeue_task(p, src_array); 1787 dequeue_task(p, src_array);
1878 dec_nr_running(p, src_rq); 1788 src_rq->nr_running--;
1879 set_task_cpu(p, this_cpu); 1789 set_task_cpu(p, this_cpu);
1880 inc_nr_running(p, this_rq); 1790 this_rq->nr_running++;
1881 enqueue_task(p, this_array); 1791 enqueue_task(p, this_array);
1882 p->timestamp = (p->timestamp - src_rq->timestamp_last_tick) 1792 p->timestamp = (p->timestamp - src_rq->timestamp_last_tick)
1883 + this_rq->timestamp_last_tick; 1793 + this_rq->timestamp_last_tick;
@@ -2056,9 +1966,9 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
2056 1966
2057 /* Bias balancing toward cpus of our domain */ 1967 /* Bias balancing toward cpus of our domain */
2058 if (local_group) 1968 if (local_group)
2059 load = __target_load(i, load_idx, idle); 1969 load = target_load(i, load_idx);
2060 else 1970 else
2061 load = __source_load(i, load_idx, idle); 1971 load = source_load(i, load_idx);
2062 1972
2063 avg_load += load; 1973 avg_load += load;
2064 } 1974 }
@@ -2171,7 +2081,7 @@ static runqueue_t *find_busiest_queue(struct sched_group *group,
2171 int i; 2081 int i;
2172 2082
2173 for_each_cpu_mask(i, group->cpumask) { 2083 for_each_cpu_mask(i, group->cpumask) {
2174 load = __source_load(i, 0, idle); 2084 load = source_load(i, 0);
2175 2085
2176 if (load > max_load) { 2086 if (load > max_load) {
2177 max_load = load; 2087 max_load = load;
@@ -3571,10 +3481,8 @@ void set_user_nice(task_t *p, long nice)
3571 goto out_unlock; 3481 goto out_unlock;
3572 } 3482 }
3573 array = p->array; 3483 array = p->array;
3574 if (array) { 3484 if (array)
3575 dequeue_task(p, array); 3485 dequeue_task(p, array);
3576 dec_prio_bias(rq, p->static_prio);
3577 }
3578 3486
3579 old_prio = p->prio; 3487 old_prio = p->prio;
3580 new_prio = NICE_TO_PRIO(nice); 3488 new_prio = NICE_TO_PRIO(nice);
@@ -3584,7 +3492,6 @@ void set_user_nice(task_t *p, long nice)
3584 3492
3585 if (array) { 3493 if (array) {
3586 enqueue_task(p, array); 3494 enqueue_task(p, array);
3587 inc_prio_bias(rq, p->static_prio);
3588 /* 3495 /*
3589 * If the task increased its priority or is running and 3496 * If the task increased its priority or is running and
3590 * lowered its priority, then reschedule its CPU: 3497 * lowered its priority, then reschedule its CPU: