[PATCH] sched: fix off-by-one bug in balance_tasks()

From: Miao Xie
Date: Tue Apr 14 2009 - 22:53:18 EST


If the load that need be moved equals the half weight of a task, I think
it is unnecessary to move this task. Or this task will be moved back and
forth.

Signed-off-by: Miao Xie <miaox@xxxxxxxxxxxxxx>
---
kernel/sched.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/sched.c b/kernel/sched.c
index 5724508..44926c8 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3085,7 +3085,7 @@ next:
if (!p || loops++ > sysctl_sched_nr_migrate)
goto out;

- if ((p->se.load.weight >> 1) > rem_load_move ||
+ if ((p->se.load.weight >> 1) >= rem_load_move ||
!can_migrate_task(p, busiest, this_cpu, sd, idle, &pinned)) {
p = iterator->next(iterator->arg);
goto next;
--
1.6.0.3


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