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-rw-r--r--kernel/torture.c260
1 files changed, 197 insertions, 63 deletions
diff --git a/kernel/torture.c b/kernel/torture.c
index a1a41484ff6d..dede150aef01 100644
--- a/kernel/torture.c
+++ b/kernel/torture.c
@@ -37,14 +37,28 @@
#include <linux/ktime.h>
#include <asm/byteorder.h>
#include <linux/torture.h>
+#include <linux/sched/rt.h>
#include "rcu/rcu.h"
+MODULE_DESCRIPTION("Common functions for in-kernel torture tests");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>");
static bool disable_onoff_at_boot;
module_param(disable_onoff_at_boot, bool, 0444);
+static bool ftrace_dump_at_shutdown;
+module_param(ftrace_dump_at_shutdown, bool, 0444);
+
+static int verbose_sleep_frequency;
+module_param(verbose_sleep_frequency, int, 0444);
+
+static int verbose_sleep_duration = 1;
+module_param(verbose_sleep_duration, int, 0444);
+
+static int random_shuffle;
+module_param(random_shuffle, int, 0444);
+
static char *torture_type;
static int verbose;
@@ -55,6 +69,96 @@ static int verbose;
static int fullstop = FULLSTOP_RMMOD;
static DEFINE_MUTEX(fullstop_mutex);
+static atomic_t verbose_sleep_counter;
+
+/*
+ * Sleep if needed from VERBOSE_TOROUT*().
+ */
+void verbose_torout_sleep(void)
+{
+ if (verbose_sleep_frequency > 0 &&
+ verbose_sleep_duration > 0 &&
+ !(atomic_inc_return(&verbose_sleep_counter) % verbose_sleep_frequency))
+ schedule_timeout_uninterruptible(verbose_sleep_duration);
+}
+EXPORT_SYMBOL_GPL(verbose_torout_sleep);
+
+/*
+ * Schedule a high-resolution-timer sleep in nanoseconds, with a 32-bit
+ * nanosecond random fuzz. This function and its friends desynchronize
+ * testing from the timer wheel.
+ */
+int torture_hrtimeout_ns(ktime_t baset_ns, u32 fuzzt_ns, const enum hrtimer_mode mode,
+ struct torture_random_state *trsp)
+{
+ ktime_t hto = baset_ns;
+
+ if (trsp)
+ hto += torture_random(trsp) % fuzzt_ns;
+ set_current_state(TASK_IDLE);
+ return schedule_hrtimeout(&hto, mode);
+}
+EXPORT_SYMBOL_GPL(torture_hrtimeout_ns);
+
+/*
+ * Schedule a high-resolution-timer sleep in microseconds, with a 32-bit
+ * nanosecond (not microsecond!) random fuzz.
+ */
+int torture_hrtimeout_us(u32 baset_us, u32 fuzzt_ns, struct torture_random_state *trsp)
+{
+ ktime_t baset_ns = baset_us * NSEC_PER_USEC;
+
+ return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);
+}
+EXPORT_SYMBOL_GPL(torture_hrtimeout_us);
+
+/*
+ * Schedule a high-resolution-timer sleep in milliseconds, with a 32-bit
+ * microsecond (not millisecond!) random fuzz.
+ */
+int torture_hrtimeout_ms(u32 baset_ms, u32 fuzzt_us, struct torture_random_state *trsp)
+{
+ ktime_t baset_ns = baset_ms * NSEC_PER_MSEC;
+ u32 fuzzt_ns;
+
+ if ((u32)~0U / NSEC_PER_USEC < fuzzt_us)
+ fuzzt_ns = (u32)~0U;
+ else
+ fuzzt_ns = fuzzt_us * NSEC_PER_USEC;
+ return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);
+}
+EXPORT_SYMBOL_GPL(torture_hrtimeout_ms);
+
+/*
+ * Schedule a high-resolution-timer sleep in jiffies, with an
+ * implied one-jiffy random fuzz. This is intended to replace calls to
+ * schedule_timeout_interruptible() and friends.
+ */
+int torture_hrtimeout_jiffies(u32 baset_j, struct torture_random_state *trsp)
+{
+ ktime_t baset_ns = jiffies_to_nsecs(baset_j);
+
+ return torture_hrtimeout_ns(baset_ns, jiffies_to_nsecs(1), HRTIMER_MODE_REL, trsp);
+}
+EXPORT_SYMBOL_GPL(torture_hrtimeout_jiffies);
+
+/*
+ * Schedule a high-resolution-timer sleep in milliseconds, with a 32-bit
+ * millisecond (not second!) random fuzz.
+ */
+int torture_hrtimeout_s(u32 baset_s, u32 fuzzt_ms, struct torture_random_state *trsp)
+{
+ ktime_t baset_ns = baset_s * NSEC_PER_SEC;
+ u32 fuzzt_ns;
+
+ if ((u32)~0U / NSEC_PER_MSEC < fuzzt_ms)
+ fuzzt_ns = (u32)~0U;
+ else
+ fuzzt_ns = fuzzt_ms * NSEC_PER_MSEC;
+ return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);
+}
+EXPORT_SYMBOL_GPL(torture_hrtimeout_s);
+
#ifdef CONFIG_HOTPLUG_CPU
/*
@@ -77,6 +181,19 @@ static unsigned long sum_online;
static int min_online = -1;
static int max_online;
+static int torture_online_cpus = NR_CPUS;
+
+/*
+ * Some torture testing leverages confusion as to the number of online
+ * CPUs. This function returns the torture-testing view of this number,
+ * which allows torture tests to load-balance appropriately.
+ */
+int torture_num_online_cpus(void)
+{
+ return READ_ONCE(torture_online_cpus);
+}
+EXPORT_SYMBOL_GPL(torture_num_online_cpus);
+
/*
* Attempt to take a CPU offline. Return false if the CPU is already
* offline or if it is not subject to CPU-hotplug operations. The
@@ -131,6 +248,8 @@ bool torture_offline(int cpu, long *n_offl_attempts, long *n_offl_successes,
*min_offl = delta;
if (*max_offl < delta)
*max_offl = delta;
+ WRITE_ONCE(torture_online_cpus, torture_online_cpus - 1);
+ WARN_ON_ONCE(torture_online_cpus <= 0);
}
return true;
@@ -187,6 +306,7 @@ bool torture_online(int cpu, long *n_onl_attempts, long *n_onl_successes,
*min_onl = delta;
if (*max_onl < delta)
*max_onl = delta;
+ WRITE_ONCE(torture_online_cpus, torture_online_cpus + 1);
}
return true;
@@ -194,6 +314,26 @@ bool torture_online(int cpu, long *n_onl_attempts, long *n_onl_successes,
EXPORT_SYMBOL_GPL(torture_online);
/*
+ * Get everything online at the beginning and ends of tests.
+ */
+static void torture_online_all(char *phase)
+{
+ int cpu;
+ int ret;
+
+ for_each_possible_cpu(cpu) {
+ if (cpu_online(cpu))
+ continue;
+ ret = add_cpu(cpu);
+ if (ret && verbose) {
+ pr_alert("%s" TORTURE_FLAG
+ "%s: %s online %d: errno %d\n",
+ __func__, phase, torture_type, cpu, ret);
+ }
+ }
+}
+
+/*
* Execute random CPU-hotplug operations at the interval specified
* by the onoff_interval.
*/
@@ -203,25 +343,12 @@ torture_onoff(void *arg)
int cpu;
int maxcpu = -1;
DEFINE_TORTURE_RANDOM(rand);
- int ret;
VERBOSE_TOROUT_STRING("torture_onoff task started");
for_each_online_cpu(cpu)
maxcpu = cpu;
WARN_ON(maxcpu < 0);
- if (!IS_MODULE(CONFIG_TORTURE_TEST)) {
- for_each_possible_cpu(cpu) {
- if (cpu_online(cpu))
- continue;
- ret = add_cpu(cpu);
- if (ret && verbose) {
- pr_alert("%s" TORTURE_FLAG
- "%s: Initial online %d: errno %d\n",
- __func__, torture_type, cpu, ret);
- }
- }
- }
-
+ torture_online_all("Initial");
if (maxcpu == 0) {
VERBOSE_TOROUT_STRING("Only one CPU, so CPU-hotplug testing is disabled");
goto stop;
@@ -229,26 +356,27 @@ torture_onoff(void *arg)
if (onoff_holdoff > 0) {
VERBOSE_TOROUT_STRING("torture_onoff begin holdoff");
- schedule_timeout_interruptible(onoff_holdoff);
+ torture_hrtimeout_jiffies(onoff_holdoff, &rand);
VERBOSE_TOROUT_STRING("torture_onoff end holdoff");
}
while (!torture_must_stop()) {
if (disable_onoff_at_boot && !rcu_inkernel_boot_has_ended()) {
- schedule_timeout_interruptible(HZ / 10);
+ torture_hrtimeout_jiffies(HZ / 10, &rand);
continue;
}
- cpu = (torture_random(&rand) >> 4) % (maxcpu + 1);
+ cpu = torture_random(&rand) % (maxcpu + 1);
if (!torture_offline(cpu,
&n_offline_attempts, &n_offline_successes,
&sum_offline, &min_offline, &max_offline))
torture_online(cpu,
&n_online_attempts, &n_online_successes,
&sum_online, &min_online, &max_online);
- schedule_timeout_interruptible(onoff_interval);
+ torture_hrtimeout_jiffies(onoff_interval, &rand);
}
stop:
torture_kthread_stopping("torture_onoff");
+ torture_online_all("Final");
return 0;
}
@@ -328,7 +456,7 @@ unsigned long
torture_random(struct torture_random_state *trsp)
{
if (--trsp->trs_count < 0) {
- trsp->trs_state += (unsigned long)local_clock();
+ trsp->trs_state += (unsigned long)local_clock() + raw_smp_processor_id();
trsp->trs_count = TORTURE_RANDOM_REFRESH;
}
trsp->trs_state = trsp->trs_state * TORTURE_RANDOM_MULT +
@@ -394,16 +522,16 @@ static void torture_shuffle_task_unregister_all(void)
* A special case is when shuffle_idle_cpu = -1, in which case we allow
* the tasks to run on all CPUs.
*/
-static void torture_shuffle_tasks(void)
+static void torture_shuffle_tasks(struct torture_random_state *trp)
{
struct shuffle_task *stp;
cpumask_setall(shuffle_tmp_mask);
- get_online_cpus();
+ cpus_read_lock();
/* No point in shuffling if there is only one online CPU (ex: UP) */
if (num_online_cpus() == 1) {
- put_online_cpus();
+ cpus_read_unlock();
return;
}
@@ -415,11 +543,13 @@ static void torture_shuffle_tasks(void)
cpumask_clear_cpu(shuffle_idle_cpu, shuffle_tmp_mask);
mutex_lock(&shuffle_task_mutex);
- list_for_each_entry(stp, &shuffle_task_list, st_l)
- set_cpus_allowed_ptr(stp->st_t, shuffle_tmp_mask);
+ list_for_each_entry(stp, &shuffle_task_list, st_l) {
+ if (!random_shuffle || torture_random(trp) & 0x1)
+ set_cpus_allowed_ptr(stp->st_t, shuffle_tmp_mask);
+ }
mutex_unlock(&shuffle_task_mutex);
- put_online_cpus();
+ cpus_read_unlock();
}
/* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
@@ -428,10 +558,12 @@ static void torture_shuffle_tasks(void)
*/
static int torture_shuffle(void *arg)
{
+ DEFINE_TORTURE_RANDOM(rand);
+
VERBOSE_TOROUT_STRING("torture_shuffle task started");
do {
- schedule_timeout_interruptible(shuffle_interval);
- torture_shuffle_tasks();
+ torture_hrtimeout_jiffies(shuffle_interval, &rand);
+ torture_shuffle_tasks(&rand);
torture_shutdown_absorb("torture_shuffle");
} while (!torture_must_stop());
torture_kthread_stopping("torture_shuffle");
@@ -448,7 +580,7 @@ int torture_shuffle_init(long shuffint)
shuffle_idle_cpu = -1;
if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
- VERBOSE_TOROUT_ERRSTRING("Failed to alloc mask");
+ TOROUT_ERRSTRING("Failed to alloc mask");
return -ENOMEM;
}
@@ -527,7 +659,8 @@ static int torture_shutdown(void *arg)
torture_shutdown_hook();
else
VERBOSE_TOROUT_STRING("No torture_shutdown_hook(), skipping.");
- rcu_ftrace_dump(DUMP_ALL);
+ if (ftrace_dump_at_shutdown)
+ rcu_ftrace_dump(DUMP_ALL);
kernel_power_off(); /* Shut down the system. */
return 0;
}
@@ -541,7 +674,7 @@ int torture_shutdown_init(int ssecs, void (*cleanup)(void))
if (ssecs > 0) {
shutdown_time = ktime_add(ktime_get(), ktime_set(ssecs, 0));
return torture_create_kthread(torture_shutdown, NULL,
- shutdown_task);
+ shutdown_task);
}
return 0;
}
@@ -588,7 +721,7 @@ static void torture_shutdown_cleanup(void)
* suddenly applied to or removed from the system.
*/
static struct task_struct *stutter_task;
-static int stutter_pause_test;
+static ktime_t stutter_till_abs_time;
static int stutter;
static int stutter_gap;
@@ -598,23 +731,16 @@ static int stutter_gap;
*/
bool stutter_wait(const char *title)
{
- int spt;
bool ret = false;
+ ktime_t till_ns;
cond_resched_tasks_rcu_qs();
- spt = READ_ONCE(stutter_pause_test);
- for (; spt; spt = READ_ONCE(stutter_pause_test)) {
+ till_ns = READ_ONCE(stutter_till_abs_time);
+ if (till_ns && ktime_before(ktime_get(), till_ns)) {
+ torture_hrtimeout_ns(till_ns, 0, HRTIMER_MODE_ABS, NULL);
ret = true;
- if (spt == 1) {
- schedule_timeout_interruptible(1);
- } else if (spt == 2) {
- while (READ_ONCE(stutter_pause_test))
- cond_resched();
- } else {
- schedule_timeout_interruptible(round_jiffies_relative(HZ));
- }
- torture_shutdown_absorb(title);
}
+ torture_shutdown_absorb(title);
return ret;
}
EXPORT_SYMBOL_GPL(stutter_wait);
@@ -625,24 +751,18 @@ EXPORT_SYMBOL_GPL(stutter_wait);
*/
static int torture_stutter(void *arg)
{
- int wtime;
+ ktime_t till_ns;
VERBOSE_TOROUT_STRING("torture_stutter task started");
do {
if (!torture_must_stop() && stutter > 1) {
- wtime = stutter;
- if (stutter > HZ + 1) {
- WRITE_ONCE(stutter_pause_test, 1);
- wtime = stutter - HZ - 1;
- schedule_timeout_interruptible(wtime);
- wtime = HZ + 1;
- }
- WRITE_ONCE(stutter_pause_test, 2);
- schedule_timeout_interruptible(wtime);
+ till_ns = ktime_add_ns(ktime_get(),
+ jiffies_to_nsecs(stutter));
+ WRITE_ONCE(stutter_till_abs_time, till_ns);
+ torture_hrtimeout_jiffies(stutter - 1, NULL);
}
- WRITE_ONCE(stutter_pause_test, 0);
if (!torture_must_stop())
- schedule_timeout_interruptible(stutter_gap);
+ torture_hrtimeout_jiffies(stutter_gap, NULL);
torture_shutdown_absorb("torture_stutter");
} while (!torture_must_stop());
torture_kthread_stopping("torture_stutter");
@@ -672,6 +792,13 @@ static void torture_stutter_cleanup(void)
stutter_task = NULL;
}
+static void
+torture_print_module_parms(void)
+{
+ pr_alert("torture module --- %s: disable_onoff_at_boot=%d ftrace_dump_at_shutdown=%d verbose_sleep_frequency=%d verbose_sleep_duration=%d random_shuffle=%d\n",
+ torture_type, disable_onoff_at_boot, ftrace_dump_at_shutdown, verbose_sleep_frequency, verbose_sleep_duration, random_shuffle);
+}
+
/*
* Initialize torture module. Please note that this is -not- invoked via
* the usual module_init() mechanism, but rather by an explicit call from
@@ -685,15 +812,16 @@ bool torture_init_begin(char *ttype, int v)
{
mutex_lock(&fullstop_mutex);
if (torture_type != NULL) {
- pr_alert("torture_init_begin: Refusing %s init: %s running.\n",
- ttype, torture_type);
- pr_alert("torture_init_begin: One torture test at a time!\n");
+ pr_alert("%s: Refusing %s init: %s running.\n",
+ __func__, ttype, torture_type);
+ pr_alert("%s: One torture test at a time!\n", __func__);
mutex_unlock(&fullstop_mutex);
return false;
}
torture_type = ttype;
verbose = v;
fullstop = FULLSTOP_DONTSTOP;
+ torture_print_module_parms();
return true;
}
EXPORT_SYMBOL_GPL(torture_init_begin);
@@ -780,11 +908,11 @@ void torture_kthread_stopping(char *title)
{
char buf[128];
- snprintf(buf, sizeof(buf), "Stopping %s", title);
+ snprintf(buf, sizeof(buf), "%s is stopping", title);
VERBOSE_TOROUT_STRING(buf);
while (!kthread_should_stop()) {
torture_shutdown_absorb(title);
- schedule_timeout_uninterruptible(1);
+ schedule_timeout_uninterruptible(HZ / 20);
}
}
EXPORT_SYMBOL_GPL(torture_kthread_stopping);
@@ -795,17 +923,23 @@ EXPORT_SYMBOL_GPL(torture_kthread_stopping);
* it starts, you will need to open-code your own.
*/
int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m,
- char *f, struct task_struct **tp)
+ char *f, struct task_struct **tp, void (*cbf)(struct task_struct *tp))
{
int ret = 0;
VERBOSE_TOROUT_STRING(m);
- *tp = kthread_run(fn, arg, "%s", s);
+ *tp = kthread_create(fn, arg, "%s", s);
if (IS_ERR(*tp)) {
ret = PTR_ERR(*tp);
- VERBOSE_TOROUT_ERRSTRING(f);
+ TOROUT_ERRSTRING(f);
*tp = NULL;
+ return ret;
}
+
+ if (cbf)
+ cbf(*tp);
+
+ wake_up_process(*tp); // Process is sleeping, so ordering provided.
torture_shuffle_task_register(*tp);
return ret;
}