torture: Stop onoff task if there is only one cpu

If the whole system has only one cpu, that cpu won't be able to be
offlined, so there is no need onoff task is stil running.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/kernel/torture.c b/kernel/torture.c
index fb39a06bbef5..75961b3decfe 100644
--- a/kernel/torture.c
+++ b/kernel/torture.c
@@ -194,6 +194,12 @@ torture_onoff(void *arg)
         for_each_online_cpu(cpu)
                 maxcpu = cpu;
         WARN_ON(maxcpu < 0);
+
+        if (maxcpu == 0) {
+                VERBOSE_TOROUT_STRING("Only one CPU, so CPU-hotplug testing is disabled");
+                goto stop;
+        }
+
         if (onoff_holdoff > 0) {
                 VERBOSE_TOROUT_STRING("torture_onoff begin holdoff");
                 schedule_timeout_interruptible(onoff_holdoff);
@@ -209,6 +215,8 @@ torture_onoff(void *arg)
                                        &sum_online, &min_online, &max_online);
                 schedule_timeout_interruptible(onoff_interval);
         }
+
+stop:
         torture_kthread_stopping("torture_onoff");
         return 0;
 }