diff options
Diffstat (limited to 'kernel/sched/fair.c')
| -rw-r--r-- | kernel/sched/fair.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index cebb312e874b..9d1734a724a8 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1155,6 +1155,7 @@ static void task_numa_compare(struct task_numa_env *env, long src_load, dst_load; long load; long imp = env->p->numa_group ? groupimp : taskimp; + long moveimp = imp; rcu_read_lock(); cur = ACCESS_ONCE(dst_rq->curr); @@ -1201,7 +1202,7 @@ static void task_numa_compare(struct task_numa_env *env, } } - if (imp < env->best_imp) + if (imp <= env->best_imp && moveimp <= env->best_imp) goto unlock; if (!cur) { @@ -1214,7 +1215,8 @@ static void task_numa_compare(struct task_numa_env *env, } /* Balance doesn't matter much if we're running a task per cpu */ - if (src_rq->nr_running == 1 && dst_rq->nr_running == 1) + if (imp > env->best_imp && src_rq->nr_running == 1 && + dst_rq->nr_running == 1) goto assign; /* @@ -1230,6 +1232,23 @@ balance: src_load += effective_load(tg, env->src_cpu, -load, -load); dst_load += effective_load(tg, env->dst_cpu, load, load); + if (moveimp > imp && moveimp > env->best_imp) { + /* + * If the improvement from just moving env->p direction is + * better than swapping tasks around, check if a move is + * possible. Store a slightly smaller score than moveimp, + * so an actually idle CPU will win. + */ + if (!load_too_imbalanced(src_load, dst_load, env)) { + imp = moveimp - 1; + cur = NULL; + goto assign; + } + } + + if (imp <= env->best_imp) + goto unlock; + if (cur) { /* Cur moves in the opposite direction. */ load = cur->se.load.weight; |
