#define LBF_NEED_BREAK 0x02
#define LBF_DST_PINNED 0x04
#define LBF_SOME_PINNED 0x08
+#define LBF_ACTIVE_LB 0x10
struct lb_env {
struct sched_domain *sd;
* our sched_group. We may want to revisit it if we couldn't
* meet load balance goals by pulling other tasks on src_cpu.
*
- * Avoid computing new_dst_cpu for NEWLY_IDLE or if we have
- * already computed one in current iteration.
+ * Avoid computing new_dst_cpu
+ * - for NEWLY_IDLE
+ * - if we have already computed one in current iteration
+ * - if it's an active balance
*/
- if (env->idle == CPU_NEWLY_IDLE || (env->flags & LBF_DST_PINNED))
+ if (env->idle == CPU_NEWLY_IDLE ||
+ env->flags & (LBF_DST_PINNED | LBF_ACTIVE_LB))
return 0;
/* Prevent to re-select dst_cpu via env's CPUs: */
/*
* Aggressive migration if:
- * 1) destination numa is preferred
- * 2) task is cache cold, or
- * 3) too many balance attempts have failed.
+ * 1) active balance
+ * 2) destination numa is preferred
+ * 3) task is cache cold, or
+ * 4) too many balance attempts have failed.
*/
+ if (env->flags & LBF_ACTIVE_LB)
+ return 1;
+
tsk_cache_hot = migrate_degrades_locality(p, env);
if (tsk_cache_hot == -1)
tsk_cache_hot = task_hot(p, env);
active_load_balance_cpu_stop, busiest,
&busiest->active_balance_work);
}
-
- /* We've kicked active balancing, force task migration. */
- sd->nr_balance_failed = sd->cache_nice_tries+1;
}
} else {
sd->nr_balance_failed = 0;
.src_cpu = busiest_rq->cpu,
.src_rq = busiest_rq,
.idle = CPU_IDLE,
- /*
- * can_migrate_task() doesn't need to compute new_dst_cpu
- * for active balancing. Since we have CPU_IDLE, but no
- * @dst_grpmask we need to make that test go away with lying
- * about DST_PINNED.
- */
- .flags = LBF_DST_PINNED,
+ .flags = LBF_ACTIVE_LB,
};
schedstat_inc(sd->alb_count);