From bb97fc31647539f1f102eed646a95e200160a150 Mon Sep 17 00:00:00 2001 From: Rik van Riel Date: Wed, 4 Jun 2014 16:33:15 -0400 Subject: [PATCH] sched/numa: Always try to migrate to preferred node at task_numa_placement() time It is possible that at task_numa_placement() time, the task's numa_preferred_nid does not change, but the task is not actually running on the preferred node at the time. In that case, we still want to attempt migration to the preferred node. Signed-off-by: Rik van Riel Signed-off-by: Peter Zijlstra Cc: mgorman@suse.de Cc: Linus Torvalds Link: http://lkml.kernel.org/r/20140604163315.1dbc7b56@cuia.bos.redhat.com Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 8fbb0116bb5a..3fa3e1839c86 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1613,11 +1613,13 @@ static void task_numa_placement(struct task_struct *p) spin_unlock_irq(group_lock); } - /* Preferred node as the node with the most faults */ - if (max_faults && max_nid != p->numa_preferred_nid) { - /* Update the preferred nid and migrate task if possible */ - sched_setnuma(p, max_nid); - numa_migrate_preferred(p); + if (max_faults) { + /* Set the new preferred node */ + if (max_nid != p->numa_preferred_nid) + sched_setnuma(p, max_nid); + + if (task_node(p) != p->numa_preferred_nid) + numa_migrate_preferred(p); } } -- 2.20.1