1 files changed, 70 insertions, 54 deletions

diff --git a/kernel/torture.c b/kernel/torture.c
index 789aeb0e1159..1ea9f67953a7 100644
--- a/kernel/torture.c
+++ b/kernel/torture.c
@@ -37,8 +37,10 @@
 #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>");
 
@@ -54,6 +56,9 @@ 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;
 
@@ -83,14 +88,15 @@ EXPORT_SYMBOL_GPL(verbose_torout_sleep);
  * 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, struct torture_random_state *trsp)
+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) >> 3) % fuzzt_ns;
-	set_current_state(TASK_UNINTERRUPTIBLE);
-	return schedule_hrtimeout(&hto, HRTIMER_MODE_REL);
+		hto += torture_random(trsp) % fuzzt_ns;
+	set_current_state(TASK_IDLE);
+	return schedule_hrtimeout(&hto, mode);
 }
 EXPORT_SYMBOL_GPL(torture_hrtimeout_ns);
 
@@ -102,7 +108,7 @@ int torture_hrtimeout_us(u32 baset_us, u32 fuzzt_ns, struct torture_random_state
 {
 	ktime_t baset_ns = baset_us * NSEC_PER_USEC;
 
-	return torture_hrtimeout_ns(baset_ns, fuzzt_ns, trsp);
+	return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);
 }
 EXPORT_SYMBOL_GPL(torture_hrtimeout_us);
 
@@ -119,7 +125,7 @@ int torture_hrtimeout_ms(u32 baset_ms, u32 fuzzt_us, struct torture_random_state
 		fuzzt_ns = (u32)~0U;
 	else
 		fuzzt_ns = fuzzt_us * NSEC_PER_USEC;
-	return torture_hrtimeout_ns(baset_ns, fuzzt_ns, trsp);
+	return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);
 }
 EXPORT_SYMBOL_GPL(torture_hrtimeout_ms);
 
@@ -132,7 +138,7 @@ 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), trsp);
+	return torture_hrtimeout_ns(baset_ns, jiffies_to_nsecs(1), HRTIMER_MODE_REL, trsp);
 }
 EXPORT_SYMBOL_GPL(torture_hrtimeout_jiffies);
 
@@ -149,7 +155,7 @@ int torture_hrtimeout_s(u32 baset_s, u32 fuzzt_ms, struct torture_random_state *
 		fuzzt_ns = (u32)~0U;
 	else
 		fuzzt_ns = fuzzt_ms * NSEC_PER_MSEC;
-	return torture_hrtimeout_ns(baset_ns, fuzzt_ns, trsp);
+	return torture_hrtimeout_ns(baset_ns, fuzzt_ns, HRTIMER_MODE_REL, trsp);
 }
 EXPORT_SYMBOL_GPL(torture_hrtimeout_s);
 
@@ -350,22 +356,24 @@ 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 (!rcu_inkernel_boot_has_ended())
+		schedule_timeout_interruptible(HZ / 10);
 	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:
@@ -450,7 +458,7 @@ 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 +
@@ -516,7 +524,7 @@ 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;
 
@@ -537,8 +545,10 @@ 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);
 
 	cpus_read_unlock();
@@ -550,10 +560,12 @@ 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");
@@ -664,7 +676,7 @@ 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;
 }
@@ -711,7 +723,7 @@ 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;
 
@@ -721,30 +733,16 @@ static int stutter_gap;
  */
 bool stutter_wait(const char *title)
 {
-	unsigned int i = 0;
 	bool ret = false;
-	int spt;
+	ktime_t till_ns;
 
 	cond_resched_tasks_rcu_qs();
-	spt = READ_ONCE(stutter_pause_test);
-	for (; spt; spt = READ_ONCE(stutter_pause_test)) {
-		if (!ret) {
-			sched_set_normal(current, MAX_NICE);
-			ret = true;
-		}
-		if (spt == 1) {
-			schedule_timeout_interruptible(1);
-		} else if (spt == 2) {
-			while (READ_ONCE(stutter_pause_test)) {
-				if (!(i++ & 0xffff))
-					torture_hrtimeout_us(10, 0, NULL);
-				cond_resched();
-			}
-		} else {
-			schedule_timeout_interruptible(round_jiffies_relative(HZ));
-		}
-		torture_shutdown_absorb(title);
+	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;
 	}
+	torture_shutdown_absorb(title);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(stutter_wait);
@@ -755,23 +753,16 @@ EXPORT_SYMBOL_GPL(stutter_wait);
  */
 static int torture_stutter(void *arg)
 {
-	DEFINE_TORTURE_RANDOM(rand);
-	int wtime;
+	ktime_t till_ns;
 
 	VERBOSE_TOROUT_STRING("torture_stutter task started");
 	do {
 		if (!torture_must_stop() && stutter > 1) {
-			wtime = stutter;
-			if (stutter > 2) {
-				WRITE_ONCE(stutter_pause_test, 1);
-				wtime = stutter - 3;
-				torture_hrtimeout_jiffies(wtime, &rand);
-				wtime = 2;
-			}
-			WRITE_ONCE(stutter_pause_test, 2);
-			torture_hrtimeout_jiffies(wtime, NULL);
+			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())
 			torture_hrtimeout_jiffies(stutter_gap, NULL);
 		torture_shutdown_absorb("torture_stutter");
@@ -803,6 +794,16 @@ static void torture_stutter_cleanup(void)
 	stutter_task = NULL;
 }
 
+static unsigned long torture_init_jiffies;
+
+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%s\n",
+		 torture_type, disable_onoff_at_boot, ftrace_dump_at_shutdown, verbose_sleep_frequency, verbose_sleep_duration, random_shuffle,
+		 rcu_inkernel_boot_has_ended() ? "" : " still booting");
+}
+
 /*
  * Initialize torture module.  Please note that this is -not- invoked via
  * the usual module_init() mechanism, but rather by an explicit call from
@@ -825,6 +826,8 @@ bool torture_init_begin(char *ttype, int v)
 	torture_type = ttype;
 	verbose = v;
 	fullstop = FULLSTOP_DONTSTOP;
+	WRITE_ONCE(torture_init_jiffies, jiffies); // Lockless reads.
+	torture_print_module_parms();
 	return true;
 }
 EXPORT_SYMBOL_GPL(torture_init_begin);
@@ -840,6 +843,15 @@ void torture_init_end(void)
 EXPORT_SYMBOL_GPL(torture_init_end);
 
 /*
+ * Get the torture_init_begin()-time value of the jiffies counter.
+ */
+unsigned long get_torture_init_jiffies(void)
+{
+	return READ_ONCE(torture_init_jiffies);
+}
+EXPORT_SYMBOL_GPL(get_torture_init_jiffies);
+
+/*
  * Clean up torture module.  Please note that this is -not- invoked via
  * the usual module_exit() mechanism, but rather by an explicit call from
  * the client torture module.  Returns true if a race with system shutdown
@@ -915,7 +927,7 @@ void torture_kthread_stopping(char *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);
@@ -926,7 +938,7 @@ 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;
 
@@ -938,6 +950,10 @@ int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m,
 		*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;