diff options
Diffstat (limited to 'kernel/sched_fair.c')
-rw-r--r-- | kernel/sched_fair.c | 28 |
1 files changed, 13 insertions, 15 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index cd18600a8a63..03496ebc4553 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c | |||
@@ -3113,19 +3113,9 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, | |||
3113 | */ | 3113 | */ |
3114 | update_sd_lb_stats(sd, this_cpu, idle, cpus, balance, &sds); | 3114 | update_sd_lb_stats(sd, this_cpu, idle, cpus, balance, &sds); |
3115 | 3115 | ||
3116 | /* Cases where imbalance does not exist from POV of this_cpu */ | 3116 | /* |
3117 | /* 1) this_cpu is not the appropriate cpu to perform load balancing | 3117 | * this_cpu is not the appropriate cpu to perform load balancing at |
3118 | * at this level. | 3118 | * this level. |
3119 | * 2) There is no busy sibling group to pull from. | ||
3120 | * 3) This group is the busiest group. | ||
3121 | * 4) This group is more busy than the avg busieness at this | ||
3122 | * sched_domain. | ||
3123 | * 5) The imbalance is within the specified limit. | ||
3124 | * | ||
3125 | * Note: when doing newidle balance, if the local group has excess | ||
3126 | * capacity (i.e. nr_running < group_capacity) and the busiest group | ||
3127 | * does not have any capacity, we force a load balance to pull tasks | ||
3128 | * to the local group. In this case, we skip past checks 3, 4 and 5. | ||
3129 | */ | 3119 | */ |
3130 | if (!(*balance)) | 3120 | if (!(*balance)) |
3131 | goto ret; | 3121 | goto ret; |
@@ -3134,19 +3124,27 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, | |||
3134 | check_asym_packing(sd, &sds, this_cpu, imbalance)) | 3124 | check_asym_packing(sd, &sds, this_cpu, imbalance)) |
3135 | return sds.busiest; | 3125 | return sds.busiest; |
3136 | 3126 | ||
3127 | /* There is no busy sibling group to pull tasks from */ | ||
3137 | if (!sds.busiest || sds.busiest_nr_running == 0) | 3128 | if (!sds.busiest || sds.busiest_nr_running == 0) |
3138 | goto out_balanced; | 3129 | goto out_balanced; |
3139 | 3130 | ||
3140 | /* SD_BALANCE_NEWIDLE trumps SMP nice when underutilized */ | 3131 | /* SD_BALANCE_NEWIDLE trumps SMP nice when underutilized */ |
3141 | if (idle == CPU_NEWLY_IDLE && sds.this_has_capacity && | 3132 | if (idle == CPU_NEWLY_IDLE && sds.this_has_capacity && |
3142 | !sds.busiest_has_capacity) | 3133 | !sds.busiest_has_capacity) |
3143 | goto force_balance; | 3134 | goto force_balance; |
3144 | 3135 | ||
3136 | /* | ||
3137 | * If the local group is more busy than the selected busiest group | ||
3138 | * don't try and pull any tasks. | ||
3139 | */ | ||
3145 | if (sds.this_load >= sds.max_load) | 3140 | if (sds.this_load >= sds.max_load) |
3146 | goto out_balanced; | 3141 | goto out_balanced; |
3147 | 3142 | ||
3143 | /* | ||
3144 | * Don't pull any tasks if this group is already above the domain | ||
3145 | * average load. | ||
3146 | */ | ||
3148 | sds.avg_load = (SCHED_LOAD_SCALE * sds.total_load) / sds.total_pwr; | 3147 | sds.avg_load = (SCHED_LOAD_SCALE * sds.total_load) / sds.total_pwr; |
3149 | |||
3150 | if (sds.this_load >= sds.avg_load) | 3148 | if (sds.this_load >= sds.avg_load) |
3151 | goto out_balanced; | 3149 | goto out_balanced; |
3152 | 3150 | ||