#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 "
/* Defaults to "only at end of test". */
static int verbose; /* Print more debug info. */
static int test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */
-static int shuffle_interval = 5; /* Interval between shuffles (in sec)*/
+static int shuffle_interval = 3; /* Interval between shuffles (in sec)*/
+static int stutter = 5; /* Start/stop testing interval (in sec) */
+static int irqreader = 1; /* RCU readers from irq (timers). */
static char *torture_type = "rcu"; /* What RCU implementation to torture. */
module_param(nreaders, int, 0444);
MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs");
module_param(shuffle_interval, int, 0444);
MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles");
+module_param(stutter, int, 0444);
+MODULE_PARM_DESC(stutter, "Number of seconds to run/halt test");
+module_param(irqreader, int, 0444);
+MODULE_PARM_DESC(irqreader, "Allow RCU readers from irq handlers");
module_param(torture_type, charp, 0444);
MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, srcu)");
static struct task_struct **reader_tasks;
static struct task_struct *stats_task;
static struct task_struct *shuffler_task;
+static struct task_struct *stutter_task;
#define RCU_TORTURE_PIPE_LEN 10
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;
static atomic_t n_rcu_torture_free;
static atomic_t n_rcu_torture_mberror;
static atomic_t n_rcu_torture_error;
+static long n_rcu_torture_timers = 0;
static struct list_head rcu_torture_removed;
+static int stutter_pause_test = 0;
+
+#if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE)
+#define RCUTORTURE_RUNNABLE_INIT 1
+#else
+#define RCUTORTURE_RUNNABLE_INIT 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.
*/
return swahw32(rrsp->rrs_state);
}
+static void
+rcu_stutter_wait(char *title)
+{
+ 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);
+ }
+}
+
/*
* Operations vector for selecting different types of tests.
*/
int (*completed)(void);
void (*deferredfree)(struct rcu_torture *p);
void (*sync)(void);
+ void (*cb_barrier)(void);
int (*stats)(char *page);
+ int irqcapable;
char *name;
};
static struct rcu_torture_ops *cur_ops = NULL;
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;
.completed = rcu_torture_completed,
.deferredfree = rcu_torture_deferred_free,
.sync = synchronize_rcu,
+ .cb_barrier = rcu_barrier,
.stats = NULL,
+ .irqcapable = 1,
.name = "rcu"
};
.completed = rcu_torture_completed,
.deferredfree = rcu_sync_torture_deferred_free,
.sync = synchronize_rcu,
+ .cb_barrier = NULL,
.stats = NULL,
+ .irqcapable = 1,
.name = "rcu_sync"
};
.completed = rcu_bh_torture_completed,
.deferredfree = rcu_bh_torture_deferred_free,
.sync = rcu_bh_torture_synchronize,
+ .cb_barrier = rcu_barrier_bh,
.stats = NULL,
+ .irqcapable = 1,
.name = "rcu_bh"
};
.completed = rcu_bh_torture_completed,
.deferredfree = rcu_sync_torture_deferred_free,
.sync = rcu_bh_torture_synchronize,
+ .cb_barrier = NULL,
.stats = NULL,
+ .irqcapable = 1,
.name = "rcu_bh_sync"
};
.completed = srcu_torture_completed,
.deferredfree = rcu_sync_torture_deferred_free,
.sync = srcu_torture_synchronize,
+ .cb_barrier = NULL,
.stats = srcu_torture_stats,
.name = "srcu"
};
return 0;
}
+static void rcu_sched_torture_deferred_free(struct rcu_torture *p)
+{
+ call_rcu_sched(&p->rtort_rcu, rcu_torture_cb);
+}
+
static void sched_torture_synchronize(void)
{
synchronize_sched();
.readdelay = rcu_read_delay, /* just reuse rcu's version. */
.readunlock = sched_torture_read_unlock,
.completed = sched_torture_completed,
- .deferredfree = rcu_sync_torture_deferred_free,
+ .deferredfree = rcu_sched_torture_deferred_free,
.sync = sched_torture_synchronize,
+ .cb_barrier = rcu_barrier_sched,
.stats = NULL,
+ .irqcapable = 1,
.name = "sched"
};
+static struct rcu_torture_ops sched_ops_sync = {
+ .init = rcu_sync_torture_init,
+ .cleanup = NULL,
+ .readlock = sched_torture_read_lock,
+ .readdelay = rcu_read_delay, /* just reuse rcu's version. */
+ .readunlock = sched_torture_read_unlock,
+ .completed = sched_torture_completed,
+ .deferredfree = rcu_sync_torture_deferred_free,
+ .sync = sched_torture_synchronize,
+ .cb_barrier = NULL,
+ .stats = NULL,
+ .name = "sched_sync"
+};
+
/*
* RCU torture writer kthread. Repeatedly substitutes a new structure
* for that pointed to by rcu_torture_current, freeing the old structure
}
rcu_torture_current_version++;
oldbatch = cur_ops->completed();
- } 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();
- } 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;
}
/*
+ * RCU torture reader from timer handler. Dereferences rcu_torture_current,
+ * incrementing the corresponding element of the pipeline array. The
+ * counter in the element should never be greater than 1, otherwise, the
+ * RCU implementation is broken.
+ */
+static void rcu_torture_timer(unsigned long unused)
+{
+ int idx;
+ int completed;
+ static DEFINE_RCU_RANDOM(rand);
+ static DEFINE_SPINLOCK(rand_lock);
+ struct rcu_torture *p;
+ int pipe_count;
+
+ idx = cur_ops->readlock();
+ completed = cur_ops->completed();
+ p = rcu_dereference(rcu_torture_current);
+ if (p == NULL) {
+ /* Leave because rcu_torture_writer is not yet underway */
+ cur_ops->readunlock(idx);
+ return;
+ }
+ if (p->rtort_mbtest == 0)
+ atomic_inc(&n_rcu_torture_mberror);
+ spin_lock(&rand_lock);
+ cur_ops->readdelay(&rand);
+ n_rcu_torture_timers++;
+ spin_unlock(&rand_lock);
+ preempt_disable();
+ pipe_count = p->rtort_pipe_count;
+ if (pipe_count > RCU_TORTURE_PIPE_LEN) {
+ /* Should not happen, but... */
+ pipe_count = RCU_TORTURE_PIPE_LEN;
+ }
+ ++__get_cpu_var(rcu_torture_count)[pipe_count];
+ completed = cur_ops->completed() - completed;
+ if (completed > RCU_TORTURE_PIPE_LEN) {
+ /* Should not happen, but... */
+ completed = RCU_TORTURE_PIPE_LEN;
+ }
+ ++__get_cpu_var(rcu_torture_batch)[completed];
+ preempt_enable();
+ cur_ops->readunlock(idx);
+}
+
+/*
* RCU torture reader kthread. Repeatedly dereferences rcu_torture_current,
* incrementing the corresponding element of the pipeline array. The
* counter in the element should never be greater than 1, otherwise, the
DEFINE_RCU_RANDOM(rand);
struct rcu_torture *p;
int pipe_count;
+ struct timer_list t;
VERBOSE_PRINTK_STRING("rcu_torture_reader task started");
set_user_nice(current, 19);
+ if (irqreader && cur_ops->irqcapable)
+ setup_timer_on_stack(&t, rcu_torture_timer, 0);
do {
+ if (irqreader && cur_ops->irqcapable) {
+ if (!timer_pending(&t))
+ mod_timer(&t, 1);
+ }
idx = cur_ops->readlock();
completed = cur_ops->completed();
p = rcu_dereference(rcu_torture_current);
preempt_enable();
cur_ops->readunlock(idx);
schedule();
- } 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())
schedule_timeout_uninterruptible(1);
return 0;
cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG);
cnt += sprintf(&page[cnt],
"rtc: %p ver: %ld tfle: %d rta: %d rtaf: %d rtf: %d "
- "rtmbe: %d",
+ "rtmbe: %d nt: %ld",
rcu_torture_current,
rcu_torture_current_version,
list_empty(&rcu_torture_freelist),
atomic_read(&n_rcu_torture_alloc),
atomic_read(&n_rcu_torture_alloc_fail),
atomic_read(&n_rcu_torture_free),
- atomic_read(&n_rcu_torture_mberror));
+ atomic_read(&n_rcu_torture_mberror),
+ n_rcu_torture_timers);
if (atomic_read(&n_rcu_torture_mberror) != 0)
cnt += sprintf(&page[cnt], " !!!");
cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG);
if (i > 1) {
cnt += sprintf(&page[cnt], "!!! ");
atomic_inc(&n_rcu_torture_error);
+ WARN_ON_ONCE(1);
}
cnt += sprintf(&page[cnt], "Reader Pipe: ");
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
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;
}
+/* Cause the rcutorture test to "stutter", starting and stopping all
+ * threads periodically.
+ */
+static int
+rcu_torture_stutter(void *arg)
+{
+ VERBOSE_PRINTK_STRING("rcu_torture_stutter task started");
+ do {
+ schedule_timeout_interruptible(stutter * HZ);
+ stutter_pause_test = 1;
+ 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;
+}
+
static inline void
rcu_torture_print_module_parms(char *tag)
{
printk(KERN_ALERT "%s" TORTURE_FLAG
"--- %s: nreaders=%d nfakewriters=%d "
"stat_interval=%d verbose=%d test_no_idle_hz=%d "
- "shuffle_interval = %d\n",
+ "shuffle_interval=%d stutter=%d irqreader=%d\n",
torture_type, tag, nrealreaders, nfakewriters,
- stat_interval, verbose, test_no_idle_hz, shuffle_interval);
+ stat_interval, verbose, test_no_idle_hz, shuffle_interval,
+ 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);
+ }
+ stutter_task = NULL;
if (shuffler_task) {
VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task");
kthread_stop(shuffler_task);
stats_task = NULL;
/* Wait for all RCU callbacks to fire. */
- rcu_barrier();
+
+ if (cur_ops->cb_barrier != NULL)
+ cur_ops->cb_barrier();
rcu_torture_stats_print(); /* -After- the stats thread is stopped! */
int firsterr = 0;
static struct rcu_torture_ops *torture_ops[] =
{ &rcu_ops, &rcu_sync_ops, &rcu_bh_ops, &rcu_bh_sync_ops,
- &srcu_ops, &sched_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++) {
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;
}
}
+ if (stutter < 0)
+ stutter = 0;
+ if (stutter) {
+ /* Create the stutter thread */
+ stutter_task = kthread_run(rcu_torture_stutter, NULL,
+ "rcu_torture_stutter");
+ if (IS_ERR(stutter_task)) {
+ firsterr = PTR_ERR(stutter_task);
+ VERBOSE_PRINTK_ERRSTRING("Failed to create stutter");
+ stutter_task = NULL;
+ 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