Revert "cpu hotplug: adjust root-domain->online span in response to hotplug event"

This reverts commit 393d94d98b19089ec172566e23557997931b137e.

Lets fix this right.

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 11 insertions, 7 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index b02e4fc25645..52b98675acb2 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -5813,13 +5813,6 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
                 /* Must be high prio: stop_machine expects to yield to it. */
                 rq = task_rq_lock(p, &flags);
                 __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1);
-
-                /* Update our root-domain */
-                if (rq->rd) {
-                        BUG_ON(!cpu_isset(cpu, rq->rd->span));
-                        cpu_set(cpu, rq->rd->online);
-                }
-
                 task_rq_unlock(rq, &flags);
                 cpu_rq(cpu)->migration_thread = p;
                 break;
@@ -5828,6 +5821,15 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
         case CPU_ONLINE_FROZEN:
                 /* Strictly unnecessary, as first user will wake it. */
                 wake_up_process(cpu_rq(cpu)->migration_thread);
+
+                /* Update our root-domain */
+                rq = cpu_rq(cpu);
+                spin_lock_irqsave(&rq->lock, flags);
+                if (rq->rd) {
+                        BUG_ON(!cpu_isset(cpu, rq->rd->span));
+                        cpu_set(cpu, rq->rd->online);
+                }
+                spin_unlock_irqrestore(&rq->lock, flags);
                 break;
 
 #ifdef CONFIG_HOTPLUG_CPU
@@ -6103,6 +6105,8 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
         rq->rd = rd;
 
         cpu_set(rq->cpu, rd->span);
+        if (cpu_isset(rq->cpu, cpu_online_map))
+                cpu_set(rq->cpu, rd->online);
 
         for (class = sched_class_highest; class; class = class->next) {
                 if (class->join_domain)