v4.19.13 snapshot.
diff --git a/include/linux/torture.h b/include/linux/torture.h
new file mode 100644
index 0000000..61dfd93
--- /dev/null
+++ b/include/linux/torture.h
@@ -0,0 +1,107 @@
+/*
+ * Common functions for in-kernel torture tests.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * Copyright IBM Corporation, 2014
+ *
+ * Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+ */
+
+#ifndef __LINUX_TORTURE_H
+#define __LINUX_TORTURE_H
+
+#include <linux/types.h>
+#include <linux/cache.h>
+#include <linux/spinlock.h>
+#include <linux/threads.h>
+#include <linux/cpumask.h>
+#include <linux/seqlock.h>
+#include <linux/lockdep.h>
+#include <linux/completion.h>
+#include <linux/debugobjects.h>
+#include <linux/bug.h>
+#include <linux/compiler.h>
+
+/* Definitions for a non-string torture-test module parameter. */
+#define torture_param(type, name, init, msg) \
+	static type name = init; \
+	module_param(name, type, 0444); \
+	MODULE_PARM_DESC(name, msg);
+
+#define TORTURE_FLAG "-torture:"
+#define TOROUT_STRING(s) \
+	pr_alert("%s" TORTURE_FLAG " %s\n", torture_type, s)
+#define VERBOSE_TOROUT_STRING(s) \
+	do { if (verbose) pr_alert("%s" TORTURE_FLAG " %s\n", torture_type, s); } while (0)
+#define VERBOSE_TOROUT_ERRSTRING(s) \
+	do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! %s\n", torture_type, s); } while (0)
+
+/* Definitions for online/offline exerciser. */
+bool torture_offline(int cpu, long *n_onl_attempts, long *n_onl_successes,
+		     unsigned long *sum_offl, int *min_onl, int *max_onl);
+bool torture_online(int cpu, long *n_onl_attempts, long *n_onl_successes,
+		    unsigned long *sum_onl, int *min_onl, int *max_onl);
+int torture_onoff_init(long ooholdoff, long oointerval);
+void torture_onoff_stats(void);
+bool torture_onoff_failures(void);
+
+/* Low-rider random number generator. */
+struct torture_random_state {
+	unsigned long trs_state;
+	long trs_count;
+};
+#define DEFINE_TORTURE_RANDOM(name) struct torture_random_state name = { 0, 0 }
+#define DEFINE_TORTURE_RANDOM_PERCPU(name) \
+	DEFINE_PER_CPU(struct torture_random_state, name)
+unsigned long torture_random(struct torture_random_state *trsp);
+
+/* Task shuffler, which causes CPUs to occasionally go idle. */
+void torture_shuffle_task_register(struct task_struct *tp);
+int torture_shuffle_init(long shuffint);
+
+/* Test auto-shutdown handling. */
+void torture_shutdown_absorb(const char *title);
+int torture_shutdown_init(int ssecs, void (*cleanup)(void));
+
+/* Task stuttering, which forces load/no-load transitions. */
+void stutter_wait(const char *title);
+int torture_stutter_init(int s);
+
+/* Initialization and cleanup. */
+bool torture_init_begin(char *ttype, int v);
+void torture_init_end(void);
+bool torture_cleanup_begin(void);
+void torture_cleanup_end(void);
+bool torture_must_stop(void);
+bool torture_must_stop_irq(void);
+void torture_kthread_stopping(char *title);
+int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m,
+			     char *f, struct task_struct **tp);
+void _torture_stop_kthread(char *m, struct task_struct **tp);
+
+#define torture_create_kthread(n, arg, tp) \
+	_torture_create_kthread(n, (arg), #n, "Creating " #n " task", \
+				"Failed to create " #n, &(tp))
+#define torture_stop_kthread(n, tp) \
+	_torture_stop_kthread("Stopping " #n " task", &(tp))
+
+#ifdef CONFIG_PREEMPT
+#define torture_preempt_schedule() preempt_schedule()
+#else
+#define torture_preempt_schedule()
+#endif
+
+#endif /* __LINUX_TORTURE_H */