sched: fix incorrect assumption that cpu 0 exists
This patch:
commit 9b5b77512dce239fa168183fa71896712232e95a
Author: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Date: Mon Oct 15 17:00:09 2007 +0200
sched: clean up code under CONFIG_FAIR_GROUP_SCHED
Introduced an assumption of the existence of CPU0 via this line
cfs_rq = tg->cfs_rq[0];
If you have no CPU0, that will be NULL. The fix seems to be just to
take whatever cfs_rq queue comes out of the for_each_possible_cpu()
loop, since they're all equally good for the destruction operation.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched.c b/kernel/sched.c
index 74dbb40..235952b 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -7041,7 +7041,7 @@
/* Destroy runqueue etc associated with a task group */
void sched_destroy_group(struct task_group *tg)
{
- struct cfs_rq *cfs_rq;
+ struct cfs_rq *cfs_rq = NULL;
int i;
for_each_possible_cpu(i) {
@@ -7049,7 +7049,7 @@
list_del_rcu(&cfs_rq->leaf_cfs_rq_list);
}
- cfs_rq = tg->cfs_rq[0];
+ BUG_ON(!cfs_rq);
/* wait for possible concurrent references to cfs_rqs complete */
call_rcu(&cfs_rq->rcu, free_sched_group);
