1 files changed, 71 insertions, 22 deletions

diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 85cb90588a55..3245b40952c6 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -39,6 +39,7 @@
 #include <linux/moduleparam.h>
 #include <linux/percpu.h>
 #include <linux/notifier.h>
+#include <linux/reboot.h>
 #include <linux/freezer.h>
 #include <linux/cpu.h>
 #include <linux/delay.h>
@@ -108,7 +109,6 @@ struct rcu_torture {
         int rtort_mbtest;
 };
 
-static int fullstop = 0;        /* stop generating callbacks at test end. */
 static LIST_HEAD(rcu_torture_freelist);
 static struct rcu_torture *rcu_torture_current = NULL;
 static long rcu_torture_current_version = 0;
@@ -136,6 +136,30 @@ static int stutter_pause_test = 0;
 #endif
 int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT;
 
+#define FULLSTOP_SIGNALED 1     /* Bail due to signal. */
+#define FULLSTOP_CLEANUP  2     /* Orderly shutdown. */
+static int fullstop;            /* stop generating callbacks at test end. */
+DEFINE_MUTEX(fullstop_mutex);   /* protect fullstop transitions and */
+                                /*  spawning of kthreads. */
+
+/*
+ * Detect and respond to a signal-based shutdown.
+ */
+static int
+rcutorture_shutdown_notify(struct notifier_block *unused1,
+                           unsigned long unused2, void *unused3)
+{
+        if (fullstop)
+                return NOTIFY_DONE;
+        if (signal_pending(current)) {
+                mutex_lock(&fullstop_mutex);
+                if (!ACCESS_ONCE(fullstop))
+                        fullstop = FULLSTOP_SIGNALED;
+                mutex_unlock(&fullstop_mutex);
+        }
+        return NOTIFY_DONE;
+}
+
 /*
  * Allocate an element from the rcu_tortures pool.
  */
@@ -199,11 +223,12 @@ rcu_random(struct rcu_random_state *rrsp)
 static void
 rcu_stutter_wait(void)
 {
-        while (stutter_pause_test || !rcutorture_runnable)
+        while ((stutter_pause_test || !rcutorture_runnable) && !fullstop) {
                 if (rcutorture_runnable)
                         schedule_timeout_interruptible(1);
                 else
                         schedule_timeout_interruptible(round_jiffies_relative(HZ));
+        }
 }
 
 /*
@@ -599,7 +624,7 @@ rcu_torture_writer(void *arg)
                 rcu_stutter_wait();
         } while (!kthread_should_stop() && !fullstop);
         VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping");
-        while (!kthread_should_stop())
+        while (!kthread_should_stop() && fullstop != FULLSTOP_SIGNALED)
                 schedule_timeout_uninterruptible(1);
         return 0;
 }
@@ -624,7 +649,7 @@ rcu_torture_fakewriter(void *arg)
         } while (!kthread_should_stop() && !fullstop);
 
         VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping");
-        while (!kthread_should_stop())
+        while (!kthread_should_stop() && fullstop != FULLSTOP_SIGNALED)
                 schedule_timeout_uninterruptible(1);
         return 0;
 }
@@ -734,7 +759,7 @@ rcu_torture_reader(void *arg)
         VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping");
         if (irqreader && cur_ops->irqcapable)
                 del_timer_sync(&t);
-        while (!kthread_should_stop())
+        while (!kthread_should_stop() && fullstop != FULLSTOP_SIGNALED)
                 schedule_timeout_uninterruptible(1);
         return 0;
 }
@@ -831,7 +856,7 @@ rcu_torture_stats(void *arg)
         do {
                 schedule_timeout_interruptible(stat_interval * HZ);
                 rcu_torture_stats_print();
-        } while (!kthread_should_stop());
+        } while (!kthread_should_stop() && !fullstop);
         VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping");
         return 0;
 }
@@ -843,49 +868,52 @@ static int rcu_idle_cpu;	/* Force all torture tasks off this CPU */
  */
 static void rcu_torture_shuffle_tasks(void)
 {
-        cpumask_t tmp_mask;
+        cpumask_var_t tmp_mask;
         int i;
 
-        cpus_setall(tmp_mask);
+        if (!alloc_cpumask_var(&tmp_mask, GFP_KERNEL))
+                BUG();
+
+        cpumask_setall(tmp_mask);
         get_online_cpus();
 
         /* No point in shuffling if there is only one online CPU (ex: UP) */
-        if (num_online_cpus() == 1) {
-                put_online_cpus();
-                return;
-        }
+        if (num_online_cpus() == 1)
+                goto out;
 
         if (rcu_idle_cpu != -1)
-                cpu_clear(rcu_idle_cpu, tmp_mask);
+                cpumask_clear_cpu(rcu_idle_cpu, tmp_mask);
 
-        set_cpus_allowed_ptr(current, &tmp_mask);
+        set_cpus_allowed_ptr(current, tmp_mask);
 
         if (reader_tasks) {
                 for (i = 0; i < nrealreaders; i++)
                         if (reader_tasks[i])
                                 set_cpus_allowed_ptr(reader_tasks[i],
-                                                     &tmp_mask);
+                                                     tmp_mask);
         }
 
         if (fakewriter_tasks) {
                 for (i = 0; i < nfakewriters; i++)
                         if (fakewriter_tasks[i])
                                 set_cpus_allowed_ptr(fakewriter_tasks[i],
-                                                     &tmp_mask);
+                                                     tmp_mask);
         }
 
         if (writer_task)
-                set_cpus_allowed_ptr(writer_task, &tmp_mask);
+                set_cpus_allowed_ptr(writer_task, tmp_mask);
 
         if (stats_task)
-                set_cpus_allowed_ptr(stats_task, &tmp_mask);
+                set_cpus_allowed_ptr(stats_task, tmp_mask);
 
         if (rcu_idle_cpu == -1)
                 rcu_idle_cpu = num_online_cpus() - 1;
         else
                 rcu_idle_cpu--;
 
+out:
         put_online_cpus();
+        free_cpumask_var(tmp_mask);
 }
 
 /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
@@ -899,7 +927,7 @@ rcu_torture_shuffle(void *arg)
         do {
                 schedule_timeout_interruptible(shuffle_interval * HZ);
                 rcu_torture_shuffle_tasks();
-        } while (!kthread_should_stop());
+        } while (!kthread_should_stop() && !fullstop);
         VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping");
         return 0;
 }
@@ -914,10 +942,10 @@ rcu_torture_stutter(void *arg)
         do {
                 schedule_timeout_interruptible(stutter * HZ);
                 stutter_pause_test = 1;
-                if (!kthread_should_stop())
+                if (!kthread_should_stop() && !fullstop)
                         schedule_timeout_interruptible(stutter * HZ);
                 stutter_pause_test = 0;
-        } while (!kthread_should_stop());
+        } while (!kthread_should_stop() && !fullstop);
         VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping");
         return 0;
 }
@@ -934,12 +962,27 @@ rcu_torture_print_module_parms(char *tag)
                 stutter, irqreader);
 }
 
+static struct notifier_block rcutorture_nb = {
+        .notifier_call = rcutorture_shutdown_notify,
+};
+
 static void
 rcu_torture_cleanup(void)
 {
         int i;
 
-        fullstop = 1;
+        mutex_lock(&fullstop_mutex);
+        if (!fullstop) {
+                /* If being signaled, let it happen, then exit. */
+                mutex_unlock(&fullstop_mutex);
+                schedule_timeout_interruptible(10 * HZ);
+                if (cur_ops->cb_barrier != NULL)
+                        cur_ops->cb_barrier();
+                return;
+        }
+        fullstop = FULLSTOP_CLEANUP;
+        mutex_unlock(&fullstop_mutex);
+        unregister_reboot_notifier(&rcutorture_nb);
         if (stutter_task) {
                 VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task");
                 kthread_stop(stutter_task);
@@ -1015,6 +1058,8 @@ rcu_torture_init(void)
                 { &rcu_ops, &rcu_sync_ops, &rcu_bh_ops, &rcu_bh_sync_ops,
                   &srcu_ops, &sched_ops, &sched_ops_sync, };
 
+        mutex_lock(&fullstop_mutex);
+
         /* Process args and tell the world that the torturer is on the job. */
         for (i = 0; i < ARRAY_SIZE(torture_ops); i++) {
                 cur_ops = torture_ops[i];
@@ -1024,6 +1069,7 @@ rcu_torture_init(void)
         if (i == ARRAY_SIZE(torture_ops)) {
                 printk(KERN_ALERT "rcutorture: invalid torture type: \"%s\"\n",
                        torture_type);
+                mutex_unlock(&fullstop_mutex);
                 return (-EINVAL);
         }
         if (cur_ops->init)
@@ -1146,9 +1192,12 @@ rcu_torture_init(void)
                         goto unwind;
                 }
         }
+        register_reboot_notifier(&rcutorture_nb);
+        mutex_unlock(&fullstop_mutex);
         return 0;
 
 unwind:
+        mutex_unlock(&fullstop_mutex);
         rcu_torture_cleanup();
         return firsterr;
 }