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-rw-r--r--kernel/rcutorture.c91
1 files changed, 86 insertions, 5 deletions
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index a58ac285fc6..a89b381a8c6 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -65,7 +65,10 @@ static int fqs_duration; /* Duration of bursts (us), 0 to disable. */
static int fqs_holdoff; /* Hold time within burst (us). */
static int fqs_stutter = 3; /* Wait time between bursts (s). */
static int onoff_interval; /* Wait time between CPU hotplugs, 0=disable. */
+static int onoff_holdoff; /* Seconds after boot before CPU hotplugs. */
static int shutdown_secs; /* Shutdown time (s). <=0 for no shutdown. */
+static int stall_cpu; /* CPU-stall duration (s). 0 for no stall. */
+static int stall_cpu_holdoff = 10; /* Time to wait until stall (s). */
static int test_boost = 1; /* Test RCU prio boost: 0=no, 1=maybe, 2=yes. */
static int test_boost_interval = 7; /* Interval between boost tests, seconds. */
static int test_boost_duration = 4; /* Duration of each boost test, seconds. */
@@ -95,8 +98,14 @@ module_param(fqs_stutter, int, 0444);
MODULE_PARM_DESC(fqs_stutter, "Wait time between fqs bursts (s)");
module_param(onoff_interval, int, 0444);
MODULE_PARM_DESC(onoff_interval, "Time between CPU hotplugs (s), 0=disable");
+module_param(onoff_holdoff, int, 0444);
+MODULE_PARM_DESC(onoff_holdoff, "Time after boot before CPU hotplugs (s)");
module_param(shutdown_secs, int, 0444);
MODULE_PARM_DESC(shutdown_secs, "Shutdown time (s), zero to disable.");
+module_param(stall_cpu, int, 0444);
+MODULE_PARM_DESC(stall_cpu, "Stall duration (s), zero to disable.");
+module_param(stall_cpu_holdoff, int, 0444);
+MODULE_PARM_DESC(stall_cpu_holdoff, "Time to wait before starting stall (s).");
module_param(test_boost, int, 0444);
MODULE_PARM_DESC(test_boost, "Test RCU prio boost: 0=no, 1=maybe, 2=yes.");
module_param(test_boost_interval, int, 0444);
@@ -129,6 +138,7 @@ static struct task_struct *shutdown_task;
#ifdef CONFIG_HOTPLUG_CPU
static struct task_struct *onoff_task;
#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+static struct task_struct *stall_task;
#define RCU_TORTURE_PIPE_LEN 10
@@ -990,12 +1000,12 @@ static void rcu_torture_timer(unsigned long unused)
rcu_read_lock_bh_held() ||
rcu_read_lock_sched_held() ||
srcu_read_lock_held(&srcu_ctl));
- do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu);
if (p == NULL) {
/* Leave because rcu_torture_writer is not yet underway */
cur_ops->readunlock(idx);
return;
}
+ do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu);
if (p->rtort_mbtest == 0)
atomic_inc(&n_rcu_torture_mberror);
spin_lock(&rand_lock);
@@ -1053,13 +1063,13 @@ rcu_torture_reader(void *arg)
rcu_read_lock_bh_held() ||
rcu_read_lock_sched_held() ||
srcu_read_lock_held(&srcu_ctl));
- do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu);
if (p == NULL) {
/* Wait for rcu_torture_writer to get underway */
cur_ops->readunlock(idx);
schedule_timeout_interruptible(HZ);
continue;
}
+ do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu);
if (p->rtort_mbtest == 0)
atomic_inc(&n_rcu_torture_mberror);
cur_ops->read_delay(&rand);
@@ -1300,13 +1310,13 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, char *tag)
"fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d "
"test_boost=%d/%d test_boost_interval=%d "
"test_boost_duration=%d shutdown_secs=%d "
- "onoff_interval=%d\n",
+ "onoff_interval=%d onoff_holdoff=%d\n",
torture_type, tag, nrealreaders, nfakewriters,
stat_interval, verbose, test_no_idle_hz, shuffle_interval,
stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter,
test_boost, cur_ops->can_boost,
test_boost_interval, test_boost_duration, shutdown_secs,
- onoff_interval);
+ onoff_interval, onoff_holdoff);
}
static struct notifier_block rcutorture_shutdown_nb = {
@@ -1410,6 +1420,11 @@ rcu_torture_onoff(void *arg)
for_each_online_cpu(cpu)
maxcpu = cpu;
WARN_ON(maxcpu < 0);
+ if (onoff_holdoff > 0) {
+ VERBOSE_PRINTK_STRING("rcu_torture_onoff begin holdoff");
+ schedule_timeout_interruptible(onoff_holdoff * HZ);
+ VERBOSE_PRINTK_STRING("rcu_torture_onoff end holdoff");
+ }
while (!kthread_should_stop()) {
cpu = (rcu_random(&rand) >> 4) % (maxcpu + 1);
if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) {
@@ -1450,12 +1465,15 @@ rcu_torture_onoff(void *arg)
static int __cpuinit
rcu_torture_onoff_init(void)
{
+ int ret;
+
if (onoff_interval <= 0)
return 0;
onoff_task = kthread_run(rcu_torture_onoff, NULL, "rcu_torture_onoff");
if (IS_ERR(onoff_task)) {
+ ret = PTR_ERR(onoff_task);
onoff_task = NULL;
- return PTR_ERR(onoff_task);
+ return ret;
}
return 0;
}
@@ -1481,6 +1499,63 @@ static void rcu_torture_onoff_cleanup(void)
#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
+/*
+ * CPU-stall kthread. It waits as specified by stall_cpu_holdoff, then
+ * induces a CPU stall for the time specified by stall_cpu.
+ */
+static int __cpuinit rcu_torture_stall(void *args)
+{
+ unsigned long stop_at;
+
+ VERBOSE_PRINTK_STRING("rcu_torture_stall task started");
+ if (stall_cpu_holdoff > 0) {
+ VERBOSE_PRINTK_STRING("rcu_torture_stall begin holdoff");
+ schedule_timeout_interruptible(stall_cpu_holdoff * HZ);
+ VERBOSE_PRINTK_STRING("rcu_torture_stall end holdoff");
+ }
+ if (!kthread_should_stop()) {
+ stop_at = get_seconds() + stall_cpu;
+ /* RCU CPU stall is expected behavior in following code. */
+ printk(KERN_ALERT "rcu_torture_stall start.\n");
+ rcu_read_lock();
+ preempt_disable();
+ while (ULONG_CMP_LT(get_seconds(), stop_at))
+ continue; /* Induce RCU CPU stall warning. */
+ preempt_enable();
+ rcu_read_unlock();
+ printk(KERN_ALERT "rcu_torture_stall end.\n");
+ }
+ rcutorture_shutdown_absorb("rcu_torture_stall");
+ while (!kthread_should_stop())
+ schedule_timeout_interruptible(10 * HZ);
+ return 0;
+}
+
+/* Spawn CPU-stall kthread, if stall_cpu specified. */
+static int __init rcu_torture_stall_init(void)
+{
+ int ret;
+
+ if (stall_cpu <= 0)
+ return 0;
+ stall_task = kthread_run(rcu_torture_stall, NULL, "rcu_torture_stall");
+ if (IS_ERR(stall_task)) {
+ ret = PTR_ERR(stall_task);
+ stall_task = NULL;
+ return ret;
+ }
+ return 0;
+}
+
+/* Clean up after the CPU-stall kthread, if one was spawned. */
+static void rcu_torture_stall_cleanup(void)
+{
+ if (stall_task == NULL)
+ return;
+ VERBOSE_PRINTK_STRING("Stopping rcu_torture_stall_task.");
+ kthread_stop(stall_task);
+}
+
static int rcutorture_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
@@ -1523,6 +1598,7 @@ rcu_torture_cleanup(void)
fullstop = FULLSTOP_RMMOD;
mutex_unlock(&fullstop_mutex);
unregister_reboot_notifier(&rcutorture_shutdown_nb);
+ rcu_torture_stall_cleanup();
if (stutter_task) {
VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task");
kthread_stop(stutter_task);
@@ -1602,6 +1678,10 @@ rcu_torture_cleanup(void)
cur_ops->cleanup();
if (atomic_read(&n_rcu_torture_error))
rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE");
+ else if (n_online_successes != n_online_attempts ||
+ n_offline_successes != n_offline_attempts)
+ rcu_torture_print_module_parms(cur_ops,
+ "End of test: RCU_HOTPLUG");
else
rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS");
}
@@ -1819,6 +1899,7 @@ rcu_torture_init(void)
}
rcu_torture_onoff_init();
register_reboot_notifier(&rcutorture_shutdown_nb);
+ rcu_torture_stall_init();
rcutorture_record_test_transition();
mutex_unlock(&fullstop_mutex);
return 0;
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-06 15:32:05 +0000