mm: numa: Revert temporarily disabling of NUMA migration
With the scan rate code working (at least for multi-instance specjbb),
the large hammer that is "sched: Do not migrate memory immediately after
switching node" can be replaced with something smarter. Revert temporarily
migration disabling and all traces of numa_migrate_seq.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1381141781-10992-61-git-send-email-mgorman@suse.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index da6fa22..8454c38 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1261,16 +1261,8 @@
{
/* Success if task is already running on preferred CPU */
p->numa_migrate_retry = 0;
- if (cpu_to_node(task_cpu(p)) == p->numa_preferred_nid) {
- /*
- * If migration is temporarily disabled due to a task migration
- * then re-enable it now as the task is running on its
- * preferred node and memory should migrate locally
- */
- if (!p->numa_migrate_seq)
- p->numa_migrate_seq++;
+ if (cpu_to_node(task_cpu(p)) == p->numa_preferred_nid)
return;
- }
/* This task has no NUMA fault statistics yet */
if (unlikely(p->numa_preferred_nid == -1))
@@ -1367,7 +1359,6 @@
if (p->numa_scan_seq == seq)
return;
p->numa_scan_seq = seq;
- p->numa_migrate_seq++;
p->numa_scan_period_max = task_scan_max(p);
/* If the task is part of a group prevent parallel updates to group stats */
@@ -4730,20 +4721,6 @@
set_task_cpu(p, env->dst_cpu);
activate_task(env->dst_rq, p, 0);
check_preempt_curr(env->dst_rq, p, 0);
-#ifdef CONFIG_NUMA_BALANCING
- if (p->numa_preferred_nid != -1) {
- int src_nid = cpu_to_node(env->src_cpu);
- int dst_nid = cpu_to_node(env->dst_cpu);
-
- /*
- * If the load balancer has moved the task then limit
- * migrations from taking place in the short term in
- * case this is a short-lived migration.
- */
- if (src_nid != dst_nid && dst_nid != p->numa_preferred_nid)
- p->numa_migrate_seq = 0;
- }
-#endif
}
/*