diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/sched_fair.c | 134 |
1 files changed, 75 insertions, 59 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index f2cc59080efa..70679b266693 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c | |||
@@ -980,12 +980,59 @@ static inline int wake_idle(int cpu, struct task_struct *p) | |||
980 | #endif | 980 | #endif |
981 | 981 | ||
982 | #ifdef CONFIG_SMP | 982 | #ifdef CONFIG_SMP |
983 | |||
984 | static int | ||
985 | wake_affine(struct rq *rq, struct sched_domain *this_sd, struct task_struct *p, | ||
986 | int cpu, int this_cpu, int sync, int idx, | ||
987 | unsigned long load, unsigned long this_load, | ||
988 | unsigned int imbalance) | ||
989 | { | ||
990 | unsigned long tl = this_load; | ||
991 | unsigned long tl_per_task; | ||
992 | |||
993 | if (!(this_sd->flags & SD_WAKE_AFFINE)) | ||
994 | return 0; | ||
995 | |||
996 | /* | ||
997 | * Attract cache-cold tasks on sync wakeups: | ||
998 | */ | ||
999 | if (sync && !task_hot(p, rq->clock, this_sd)) | ||
1000 | return 1; | ||
1001 | |||
1002 | schedstat_inc(p, se.nr_wakeups_affine_attempts); | ||
1003 | tl_per_task = cpu_avg_load_per_task(this_cpu); | ||
1004 | |||
1005 | /* | ||
1006 | * If sync wakeup then subtract the (maximum possible) | ||
1007 | * effect of the currently running task from the load | ||
1008 | * of the current CPU: | ||
1009 | */ | ||
1010 | if (sync) | ||
1011 | tl -= current->se.load.weight; | ||
1012 | |||
1013 | if ((tl <= load && tl + target_load(cpu, idx) <= tl_per_task) || | ||
1014 | 100*(tl + p->se.load.weight) <= imbalance*load) { | ||
1015 | /* | ||
1016 | * This domain has SD_WAKE_AFFINE and | ||
1017 | * p is cache cold in this domain, and | ||
1018 | * there is no bad imbalance. | ||
1019 | */ | ||
1020 | schedstat_inc(this_sd, ttwu_move_affine); | ||
1021 | schedstat_inc(p, se.nr_wakeups_affine); | ||
1022 | |||
1023 | return 1; | ||
1024 | } | ||
1025 | return 0; | ||
1026 | } | ||
1027 | |||
983 | static int select_task_rq_fair(struct task_struct *p, int sync) | 1028 | static int select_task_rq_fair(struct task_struct *p, int sync) |
984 | { | 1029 | { |
985 | int cpu, this_cpu; | ||
986 | struct rq *rq; | ||
987 | struct sched_domain *sd, *this_sd = NULL; | 1030 | struct sched_domain *sd, *this_sd = NULL; |
988 | int new_cpu; | 1031 | unsigned long load, this_load; |
1032 | int cpu, this_cpu, new_cpu; | ||
1033 | unsigned int imbalance; | ||
1034 | struct rq *rq; | ||
1035 | int idx; | ||
989 | 1036 | ||
990 | cpu = task_cpu(p); | 1037 | cpu = task_cpu(p); |
991 | rq = task_rq(p); | 1038 | rq = task_rq(p); |
@@ -1008,66 +1055,35 @@ static int select_task_rq_fair(struct task_struct *p, int sync) | |||
1008 | /* | 1055 | /* |
1009 | * Check for affine wakeup and passive balancing possibilities. | 1056 | * Check for affine wakeup and passive balancing possibilities. |
1010 | */ | 1057 | */ |
1011 | if (this_sd) { | 1058 | if (!this_sd) |
1012 | int idx = this_sd->wake_idx; | 1059 | goto out_keep_cpu; |
1013 | unsigned int imbalance; | ||
1014 | unsigned long load, this_load; | ||
1015 | |||
1016 | imbalance = 100 + (this_sd->imbalance_pct - 100) / 2; | ||
1017 | |||
1018 | load = source_load(cpu, idx); | ||
1019 | this_load = target_load(this_cpu, idx); | ||
1020 | |||
1021 | new_cpu = this_cpu; /* Wake to this CPU if we can */ | ||
1022 | |||
1023 | if (this_sd->flags & SD_WAKE_AFFINE) { | ||
1024 | unsigned long tl = this_load; | ||
1025 | unsigned long tl_per_task; | ||
1026 | |||
1027 | /* | ||
1028 | * Attract cache-cold tasks on sync wakeups: | ||
1029 | */ | ||
1030 | if (sync && !task_hot(p, rq->clock, this_sd)) | ||
1031 | goto out_set_cpu; | ||
1032 | |||
1033 | schedstat_inc(p, se.nr_wakeups_affine_attempts); | ||
1034 | tl_per_task = cpu_avg_load_per_task(this_cpu); | ||
1035 | |||
1036 | /* | ||
1037 | * If sync wakeup then subtract the (maximum possible) | ||
1038 | * effect of the currently running task from the load | ||
1039 | * of the current CPU: | ||
1040 | */ | ||
1041 | if (sync) | ||
1042 | tl -= current->se.load.weight; | ||
1043 | |||
1044 | if ((tl <= load && | ||
1045 | tl + target_load(cpu, idx) <= tl_per_task) || | ||
1046 | 100*(tl + p->se.load.weight) <= imbalance*load) { | ||
1047 | /* | ||
1048 | * This domain has SD_WAKE_AFFINE and | ||
1049 | * p is cache cold in this domain, and | ||
1050 | * there is no bad imbalance. | ||
1051 | */ | ||
1052 | schedstat_inc(this_sd, ttwu_move_affine); | ||
1053 | schedstat_inc(p, se.nr_wakeups_affine); | ||
1054 | goto out_set_cpu; | ||
1055 | } | ||
1056 | } | ||
1057 | 1060 | ||
1058 | /* | 1061 | idx = this_sd->wake_idx; |
1059 | * Start passive balancing when half the imbalance_pct | 1062 | |
1060 | * limit is reached. | 1063 | imbalance = 100 + (this_sd->imbalance_pct - 100) / 2; |
1061 | */ | 1064 | |
1062 | if (this_sd->flags & SD_WAKE_BALANCE) { | 1065 | load = source_load(cpu, idx); |
1063 | if (imbalance*this_load <= 100*load) { | 1066 | this_load = target_load(this_cpu, idx); |
1064 | schedstat_inc(this_sd, ttwu_move_balance); | 1067 | |
1065 | schedstat_inc(p, se.nr_wakeups_passive); | 1068 | new_cpu = this_cpu; /* Wake to this CPU if we can */ |
1066 | goto out_set_cpu; | 1069 | |
1067 | } | 1070 | if (wake_affine(rq, this_sd, p, cpu, this_cpu, sync, idx, |
1071 | load, this_load, imbalance)) | ||
1072 | goto out_set_cpu; | ||
1073 | |||
1074 | /* | ||
1075 | * Start passive balancing when half the imbalance_pct | ||
1076 | * limit is reached. | ||
1077 | */ | ||
1078 | if (this_sd->flags & SD_WAKE_BALANCE) { | ||
1079 | if (imbalance*this_load <= 100*load) { | ||
1080 | schedstat_inc(this_sd, ttwu_move_balance); | ||
1081 | schedstat_inc(p, se.nr_wakeups_passive); | ||
1082 | goto out_set_cpu; | ||
1068 | } | 1083 | } |
1069 | } | 1084 | } |
1070 | 1085 | ||
1086 | out_keep_cpu: | ||
1071 | new_cpu = cpu; /* Could not wake to this_cpu. Wake to cpu instead */ | 1087 | new_cpu = cpu; /* Could not wake to this_cpu. Wake to cpu instead */ |
1072 | out_set_cpu: | 1088 | out_set_cpu: |
1073 | return wake_idle(new_cpu, p); | 1089 | return wake_idle(new_cpu, p); |