#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>
-#include <linux/byteorder/swabb.h>
#include <linux/stat.h>
#include <linux/srcu.h>
#include <linux/slab.h>
+#include <asm/byteorder.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and "
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;
#endif
int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT;
+/* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */
+
+#define FULLSTOP_DONTSTOP 0 /* Normal operation. */
+#define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */
+#define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */
+static int fullstop = FULLSTOP_RMMOD;
+DEFINE_MUTEX(fullstop_mutex); /* Protect fullstop transitions and spawning */
+ /* of kthreads. */
+
+/*
+ * Detect and respond to a system shutdown.
+ */
+static int
+rcutorture_shutdown_notify(struct notifier_block *unused1,
+ unsigned long unused2, void *unused3)
+{
+ mutex_lock(&fullstop_mutex);
+ if (fullstop == FULLSTOP_DONTSTOP)
+ fullstop = FULLSTOP_SHUTDOWN;
+ else
+ printk(KERN_WARNING /* but going down anyway, so... */
+ "Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
+ mutex_unlock(&fullstop_mutex);
+ return NOTIFY_DONE;
+}
+
+/*
+ * Absorb kthreads into a kernel function that won't return, so that
+ * they won't ever access module text or data again.
+ */
+static void rcutorture_shutdown_absorb(char *title)
+{
+ if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
+ printk(KERN_NOTICE
+ "rcutorture thread %s parking due to system shutdown\n",
+ title);
+ schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
+ }
+}
+
/*
* Allocate an element from the rcu_tortures pool.
*/
}
static void
-rcu_stutter_wait(void)
+rcu_stutter_wait(char *title)
{
- while (stutter_pause_test || !rcutorture_runnable)
+ while (stutter_pause_test || !rcutorture_runnable) {
if (rcutorture_runnable)
schedule_timeout_interruptible(1);
else
schedule_timeout_interruptible(round_jiffies_relative(HZ));
+ rcutorture_shutdown_absorb(title);
+ }
}
/*
int i;
struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu);
- if (fullstop) {
+ if (fullstop != FULLSTOP_DONTSTOP) {
/* Test is ending, just drop callbacks on the floor. */
/* The next initialization will pick up the pieces. */
return;
}
rcu_torture_current_version++;
oldbatch = cur_ops->completed();
- rcu_stutter_wait();
- } while (!kthread_should_stop() && !fullstop);
+ rcu_stutter_wait("rcu_torture_writer");
+ } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping");
+ rcutorture_shutdown_absorb("rcu_torture_writer");
while (!kthread_should_stop())
schedule_timeout_uninterruptible(1);
return 0;
schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10);
udelay(rcu_random(&rand) & 0x3ff);
cur_ops->sync();
- rcu_stutter_wait();
- } while (!kthread_should_stop() && !fullstop);
+ rcu_stutter_wait("rcu_torture_fakewriter");
+ } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping");
+ rcutorture_shutdown_absorb("rcu_torture_fakewriter");
while (!kthread_should_stop())
schedule_timeout_uninterruptible(1);
return 0;
preempt_enable();
cur_ops->readunlock(idx);
schedule();
- rcu_stutter_wait();
- } while (!kthread_should_stop() && !fullstop);
+ rcu_stutter_wait("rcu_torture_reader");
+ } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping");
+ rcutorture_shutdown_absorb("rcu_torture_reader");
if (irqreader && cur_ops->irqcapable)
del_timer_sync(&t);
while (!kthread_should_stop())
do {
schedule_timeout_interruptible(stat_interval * HZ);
rcu_torture_stats_print();
+ rcutorture_shutdown_absorb("rcu_torture_stats");
} while (!kthread_should_stop());
VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping");
return 0;
do {
schedule_timeout_interruptible(shuffle_interval * HZ);
rcu_torture_shuffle_tasks();
+ rcutorture_shutdown_absorb("rcu_torture_shuffle");
} while (!kthread_should_stop());
VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping");
return 0;
if (!kthread_should_stop())
schedule_timeout_interruptible(stutter * HZ);
stutter_pause_test = 0;
+ rcutorture_shutdown_absorb("rcu_torture_stutter");
} while (!kthread_should_stop());
VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping");
return 0;
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 == FULLSTOP_SHUTDOWN) {
+ printk(KERN_WARNING /* but going down anyway, so... */
+ "Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
+ mutex_unlock(&fullstop_mutex);
+ schedule_timeout_uninterruptible(10);
+ if (cur_ops->cb_barrier != NULL)
+ cur_ops->cb_barrier();
+ return;
+ }
+ fullstop = FULLSTOP_RMMOD;
+ mutex_unlock(&fullstop_mutex);
+ unregister_reboot_notifier(&rcutorture_nb);
if (stutter_task) {
VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task");
kthread_stop(stutter_task);
{ &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];
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)
else
nrealreaders = 2 * num_online_cpus();
rcu_torture_print_module_parms("Start of test");
- fullstop = 0;
+ fullstop = FULLSTOP_DONTSTOP;
/* Set up the freelist. */
goto unwind;
}
}
+ register_reboot_notifier(&rcutorture_nb);
+ mutex_unlock(&fullstop_mutex);
return 0;
unwind:
+ mutex_unlock(&fullstop_mutex);
rcu_torture_cleanup();
return firsterr;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff