--- /dev/null
+/*
+ * 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 (C) IBM Corporation, 2014
+ *
+ * Author: Paul E. McKenney <paulmck@us.ibm.com>
+ * Based on kernel/rcu/torture.c.
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/err.h>
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/completion.h>
+#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/stat.h>
+#include <linux/slab.h>
+#include <linux/trace_clock.h>
+#include <asm/byteorder.h>
+#include <linux/torture.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>");
+
+static char *torture_type;
+static bool verbose;
+
+/* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */
+#define FULLSTOP_DONTSTOP 0 /* Normal operation. */
+#define FULLSTOP_SHUTDOWN 1 /* System shutdown with torture running. */
+#define FULLSTOP_RMMOD 2 /* Normal rmmod of torture. */
+static int fullstop = FULLSTOP_RMMOD;
+static DEFINE_MUTEX(fullstop_mutex);
+static int *torture_runnable;
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Variables for online-offline handling. Only present if CPU hotplug
+ * is enabled, otherwise does nothing.
+ */
+
+static struct task_struct *onoff_task;
+static long onoff_holdoff;
+static long onoff_interval;
+static long n_offline_attempts;
+static long n_offline_successes;
+static unsigned long sum_offline;
+static int min_offline = -1;
+static int max_offline;
+static long n_online_attempts;
+static long n_online_successes;
+static unsigned long sum_online;
+static int min_online = -1;
+static int max_online;
+
+/*
+ * Execute random CPU-hotplug operations at the interval specified
+ * by the onoff_interval.
+ */
+static int
+torture_onoff(void *arg)
+{
+ int cpu;
+ unsigned long delta;
+ int maxcpu = -1;
+ DEFINE_TORTURE_RANDOM(rand);
+ int ret;
+ unsigned long starttime;
+
+ VERBOSE_TOROUT_STRING("torture_onoff task started");
+ for_each_online_cpu(cpu)
+ maxcpu = cpu;
+ WARN_ON(maxcpu < 0);
+ if (onoff_holdoff > 0) {
+ VERBOSE_TOROUT_STRING("torture_onoff begin holdoff");
+ schedule_timeout_interruptible(onoff_holdoff);
+ VERBOSE_TOROUT_STRING("torture_onoff end holdoff");
+ }
+ while (!torture_must_stop()) {
+ cpu = (torture_random(&rand) >> 4) % (maxcpu + 1);
+ if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: offlining %d\n",
+ torture_type, cpu);
+ starttime = jiffies;
+ n_offline_attempts++;
+ ret = cpu_down(cpu);
+ if (ret) {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: offline %d failed: errno %d\n",
+ torture_type, cpu, ret);
+ } else {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: offlined %d\n",
+ torture_type, cpu);
+ n_offline_successes++;
+ delta = jiffies - starttime;
+ sum_offline += delta;
+ if (min_offline < 0) {
+ min_offline = delta;
+ max_offline = delta;
+ }
+ if (min_offline > delta)
+ min_offline = delta;
+ if (max_offline < delta)
+ max_offline = delta;
+ }
+ } else if (cpu_is_hotpluggable(cpu)) {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: onlining %d\n",
+ torture_type, cpu);
+ starttime = jiffies;
+ n_online_attempts++;
+ ret = cpu_up(cpu);
+ if (ret) {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: online %d failed: errno %d\n",
+ torture_type, cpu, ret);
+ } else {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: onlined %d\n",
+ torture_type, cpu);
+ n_online_successes++;
+ delta = jiffies - starttime;
+ sum_online += delta;
+ if (min_online < 0) {
+ min_online = delta;
+ max_online = delta;
+ }
+ if (min_online > delta)
+ min_online = delta;
+ if (max_online < delta)
+ max_online = delta;
+ }
+ }
+ schedule_timeout_interruptible(onoff_interval);
+ }
+ torture_kthread_stopping("torture_onoff");
+ return 0;
+}
+
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+
+/*
+ * Initiate online-offline handling.
+ */
+int torture_onoff_init(long ooholdoff, long oointerval)
+{
+ int ret = 0;
+
+#ifdef CONFIG_HOTPLUG_CPU
+ onoff_holdoff = ooholdoff;
+ onoff_interval = oointerval;
+ if (onoff_interval <= 0)
+ return 0;
+ ret = torture_create_kthread(torture_onoff, NULL, onoff_task);
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+ return ret;
+}
+EXPORT_SYMBOL_GPL(torture_onoff_init);
+
+/*
+ * Clean up after online/offline testing.
+ */
+static void torture_onoff_cleanup(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ if (onoff_task == NULL)
+ return;
+ VERBOSE_TOROUT_STRING("Stopping torture_onoff task");
+ kthread_stop(onoff_task);
+ onoff_task = NULL;
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+}
+EXPORT_SYMBOL_GPL(torture_onoff_cleanup);
+
+/*
+ * Print online/offline testing statistics.
+ */
+void torture_onoff_stats(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ pr_cont("onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
+ n_online_successes, n_online_attempts,
+ n_offline_successes, n_offline_attempts,
+ min_online, max_online,
+ min_offline, max_offline,
+ sum_online, sum_offline, HZ);
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+}
+EXPORT_SYMBOL_GPL(torture_onoff_stats);
+
+/*
+ * Were all the online/offline operations successful?
+ */
+bool torture_onoff_failures(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ return n_online_successes != n_online_attempts ||
+ n_offline_successes != n_offline_attempts;
+#else /* #ifdef CONFIG_HOTPLUG_CPU */
+ return false;
+#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
+}
+EXPORT_SYMBOL_GPL(torture_onoff_failures);
+
+#define TORTURE_RANDOM_MULT 39916801 /* prime */
+#define TORTURE_RANDOM_ADD 479001701 /* prime */
+#define TORTURE_RANDOM_REFRESH 10000
+
+/*
+ * Crude but fast random-number generator. Uses a linear congruential
+ * generator, with occasional help from cpu_clock().
+ */
+unsigned long
+torture_random(struct torture_random_state *trsp)
+{
+ if (--trsp->trs_count < 0) {
+ trsp->trs_state += (unsigned long)local_clock();
+ trsp->trs_count = TORTURE_RANDOM_REFRESH;
+ }
+ trsp->trs_state = trsp->trs_state * TORTURE_RANDOM_MULT +
+ TORTURE_RANDOM_ADD;
+ return swahw32(trsp->trs_state);
+}
+EXPORT_SYMBOL_GPL(torture_random);
+
+/*
+ * Variables for shuffling. The idea is to ensure that each CPU stays
+ * idle for an extended period to test interactions with dyntick idle,
+ * as well as interactions with any per-CPU varibles.
+ */
+struct shuffle_task {
+ struct list_head st_l;
+ struct task_struct *st_t;
+};
+
+static long shuffle_interval; /* In jiffies. */
+static struct task_struct *shuffler_task;
+static cpumask_var_t shuffle_tmp_mask;
+static int shuffle_idle_cpu; /* Force all torture tasks off this CPU */
+static struct list_head shuffle_task_list = LIST_HEAD_INIT(shuffle_task_list);
+static DEFINE_MUTEX(shuffle_task_mutex);
+
+/*
+ * Register a task to be shuffled. If there is no memory, just splat
+ * and don't bother registering.
+ */
+void torture_shuffle_task_register(struct task_struct *tp)
+{
+ struct shuffle_task *stp;
+
+ if (WARN_ON_ONCE(tp == NULL))
+ return;
+ stp = kmalloc(sizeof(*stp), GFP_KERNEL);
+ if (WARN_ON_ONCE(stp == NULL))
+ return;
+ stp->st_t = tp;
+ mutex_lock(&shuffle_task_mutex);
+ list_add(&stp->st_l, &shuffle_task_list);
+ mutex_unlock(&shuffle_task_mutex);
+}
+EXPORT_SYMBOL_GPL(torture_shuffle_task_register);
+
+/*
+ * Unregister all tasks, for example, at the end of the torture run.
+ */
+static void torture_shuffle_task_unregister_all(void)
+{
+ struct shuffle_task *stp;
+ struct shuffle_task *p;
+
+ mutex_lock(&shuffle_task_mutex);
+ list_for_each_entry_safe(stp, p, &shuffle_task_list, st_l) {
+ list_del(&stp->st_l);
+ kfree(stp);
+ }
+ mutex_unlock(&shuffle_task_mutex);
+}
+
+/* Shuffle tasks such that we allow shuffle_idle_cpu to become idle.
+ * 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)
+{
+ struct shuffle_task *stp;
+
+ cpumask_setall(shuffle_tmp_mask);
+ get_online_cpus();
+
+ /* No point in shuffling if there is only one online CPU (ex: UP) */
+ if (num_online_cpus() == 1) {
+ put_online_cpus();
+ return;
+ }
+
+ /* Advance to the next CPU. Upon overflow, don't idle any CPUs. */
+ shuffle_idle_cpu = cpumask_next(shuffle_idle_cpu, shuffle_tmp_mask);
+ if (shuffle_idle_cpu >= nr_cpu_ids)
+ shuffle_idle_cpu = -1;
+ else
+ 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);
+ mutex_unlock(&shuffle_task_mutex);
+
+ put_online_cpus();
+}
+
+/* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
+ * system to become idle at a time and cut off its timer ticks. This is meant
+ * to test the support for such tickless idle CPU in RCU.
+ */
+static int torture_shuffle(void *arg)
+{
+ VERBOSE_TOROUT_STRING("torture_shuffle task started");
+ do {
+ schedule_timeout_interruptible(shuffle_interval);
+ torture_shuffle_tasks();
+ torture_shutdown_absorb("torture_shuffle");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("torture_shuffle");
+ return 0;
+}
+
+/*
+ * Start the shuffler, with shuffint in jiffies.
+ */
+int torture_shuffle_init(long shuffint)
+{
+ shuffle_interval = shuffint;
+
+ shuffle_idle_cpu = -1;
+
+ if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
+ VERBOSE_TOROUT_ERRSTRING("Failed to alloc mask");
+ return -ENOMEM;
+ }
+
+ /* Create the shuffler thread */
+ return torture_create_kthread(torture_shuffle, NULL, shuffler_task);
+}
+EXPORT_SYMBOL_GPL(torture_shuffle_init);
+
+/*
+ * Stop the shuffling.
+ */
+static void torture_shuffle_cleanup(void)
+{
+ torture_shuffle_task_unregister_all();
+ if (shuffler_task) {
+ VERBOSE_TOROUT_STRING("Stopping torture_shuffle task");
+ kthread_stop(shuffler_task);
+ free_cpumask_var(shuffle_tmp_mask);
+ }
+ shuffler_task = NULL;
+}
+EXPORT_SYMBOL_GPL(torture_shuffle_cleanup);
+
+/*
+ * Variables for auto-shutdown. This allows "lights out" torture runs
+ * to be fully scripted.
+ */
+static int shutdown_secs; /* desired test duration in seconds. */
+static struct task_struct *shutdown_task;
+static unsigned long shutdown_time; /* jiffies to system shutdown. */
+static void (*torture_shutdown_hook)(void);
+
+/*
+ * Absorb kthreads into a kernel function that won't return, so that
+ * they won't ever access module text or data again.
+ */
+void torture_shutdown_absorb(const char *title)
+{
+ while (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
+ pr_notice("torture thread %s parking due to system shutdown\n",
+ title);
+ schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
+ }
+}
+EXPORT_SYMBOL_GPL(torture_shutdown_absorb);
+
+/*
+ * Cause the torture test to shutdown the system after the test has
+ * run for the time specified by the shutdown_secs parameter.
+ */
+static int torture_shutdown(void *arg)
+{
+ long delta;
+ unsigned long jiffies_snap;
+
+ VERBOSE_TOROUT_STRING("torture_shutdown task started");
+ jiffies_snap = jiffies;
+ while (ULONG_CMP_LT(jiffies_snap, shutdown_time) &&
+ !torture_must_stop()) {
+ delta = shutdown_time - jiffies_snap;
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_shutdown task: %lu jiffies remaining\n",
+ torture_type, delta);
+ schedule_timeout_interruptible(delta);
+ jiffies_snap = jiffies;
+ }
+ if (torture_must_stop()) {
+ torture_kthread_stopping("torture_shutdown");
+ return 0;
+ }
+
+ /* OK, shut down the system. */
+
+ VERBOSE_TOROUT_STRING("torture_shutdown task shutting down system");
+ shutdown_task = NULL; /* Avoid self-kill deadlock. */
+ if (torture_shutdown_hook)
+ torture_shutdown_hook();
+ else
+ VERBOSE_TOROUT_STRING("No torture_shutdown_hook(), skipping.");
+ kernel_power_off(); /* Shut down the system. */
+ return 0;
+}
+
+/*
+ * Start up the shutdown task.
+ */
+int torture_shutdown_init(int ssecs, void (*cleanup)(void))
+{
+ int ret = 0;
+
+ shutdown_secs = ssecs;
+ torture_shutdown_hook = cleanup;
+ if (shutdown_secs > 0) {
+ shutdown_time = jiffies + shutdown_secs * HZ;
+ ret = torture_create_kthread(torture_shutdown, NULL,
+ shutdown_task);
+ }
+ return ret;
+}
+EXPORT_SYMBOL_GPL(torture_shutdown_init);
+
+/*
+ * Detect and respond to a system shutdown.
+ */
+static int torture_shutdown_notify(struct notifier_block *unused1,
+ unsigned long unused2, void *unused3)
+{
+ mutex_lock(&fullstop_mutex);
+ if (ACCESS_ONCE(fullstop) == FULLSTOP_DONTSTOP) {
+ VERBOSE_TOROUT_STRING("Unscheduled system shutdown detected");
+ ACCESS_ONCE(fullstop) = FULLSTOP_SHUTDOWN;
+ } else {
+ pr_warn("Concurrent rmmod and shutdown illegal!\n");
+ }
+ mutex_unlock(&fullstop_mutex);
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block torture_shutdown_nb = {
+ .notifier_call = torture_shutdown_notify,
+};
+
+/*
+ * Shut down the shutdown task. Say what??? Heh! This can happen if
+ * the torture module gets an rmmod before the shutdown time arrives. ;-)
+ */
+static void torture_shutdown_cleanup(void)
+{
+ unregister_reboot_notifier(&torture_shutdown_nb);
+ if (shutdown_task != NULL) {
+ VERBOSE_TOROUT_STRING("Stopping torture_shutdown task");
+ kthread_stop(shutdown_task);
+ }
+ shutdown_task = NULL;
+}
+
+/*
+ * Variables for stuttering, which means to periodically pause and
+ * restart testing in order to catch bugs that appear when load is
+ * suddenly applied to or removed from the system.
+ */
+static struct task_struct *stutter_task;
+static int stutter_pause_test;
+static int stutter;
+
+/*
+ * Block until the stutter interval ends. This must be called periodically
+ * by all running kthreads that need to be subject to stuttering.
+ */
+void stutter_wait(const char *title)
+{
+ while (ACCESS_ONCE(stutter_pause_test) ||
+ (torture_runnable && !ACCESS_ONCE(*torture_runnable))) {
+ if (stutter_pause_test)
+ if (ACCESS_ONCE(stutter_pause_test) == 1)
+ schedule_timeout_interruptible(1);
+ else
+ while (ACCESS_ONCE(stutter_pause_test))
+ cond_resched();
+ else
+ schedule_timeout_interruptible(round_jiffies_relative(HZ));
+ torture_shutdown_absorb(title);
+ }
+}
+EXPORT_SYMBOL_GPL(stutter_wait);
+
+/*
+ * Cause the torture test to "stutter", starting and stopping all
+ * threads periodically.
+ */
+static int torture_stutter(void *arg)
+{
+ VERBOSE_TOROUT_STRING("torture_stutter task started");
+ do {
+ if (!torture_must_stop()) {
+ if (stutter > 1) {
+ schedule_timeout_interruptible(stutter - 1);
+ ACCESS_ONCE(stutter_pause_test) = 2;
+ }
+ schedule_timeout_interruptible(1);
+ ACCESS_ONCE(stutter_pause_test) = 1;
+ }
+ if (!torture_must_stop())
+ schedule_timeout_interruptible(stutter);
+ ACCESS_ONCE(stutter_pause_test) = 0;
+ torture_shutdown_absorb("torture_stutter");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("torture_stutter");
+ return 0;
+}
+
+/*
+ * Initialize and kick off the torture_stutter kthread.
+ */
+int torture_stutter_init(int s)
+{
+ int ret;
+
+ stutter = s;
+ ret = torture_create_kthread(torture_stutter, NULL, stutter_task);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(torture_stutter_init);
+
+/*
+ * Cleanup after the torture_stutter kthread.
+ */
+static void torture_stutter_cleanup(void)
+{
+ if (!stutter_task)
+ return;
+ VERBOSE_TOROUT_STRING("Stopping torture_stutter task");
+ kthread_stop(stutter_task);
+ stutter_task = NULL;
+}
+
+/*
+ * Initialize torture module. Please note that this is -not- invoked via
+ * the usual module_init() mechanism, but rather by an explicit call from
+ * the client torture module. This call must be paired with a later
+ * torture_init_end().
+ *
+ * The runnable parameter points to a flag that controls whether or not
+ * the test is currently runnable. If there is no such flag, pass in NULL.
+ */
+bool torture_init_begin(char *ttype, bool v, int *runnable)
+{
+ mutex_lock(&fullstop_mutex);
+ if (torture_type != NULL) {
+ pr_alert("torture_init_begin: refusing %s init: %s running",
+ ttype, torture_type);
+ mutex_unlock(&fullstop_mutex);
+ return false;
+ }
+ torture_type = ttype;
+ verbose = v;
+ torture_runnable = runnable;
+ fullstop = FULLSTOP_DONTSTOP;
+ return true;
+}
+EXPORT_SYMBOL_GPL(torture_init_begin);
+
+/*
+ * Tell the torture module that initialization is complete.
+ */
+void torture_init_end(void)
+{
+ mutex_unlock(&fullstop_mutex);
+ register_reboot_notifier(&torture_shutdown_nb);
+}
+EXPORT_SYMBOL_GPL(torture_init_end);
+
+/*
+ * 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
+ * is detected, otherwise, all kthreads started by functions in this file
+ * will be shut down.
+ *
+ * This must be called before the caller starts shutting down its own
+ * kthreads.
+ *
+ * Both torture_cleanup_begin() and torture_cleanup_end() must be paired,
+ * in order to correctly perform the cleanup. They are separated because
+ * threads can still need to reference the torture_type type, thus nullify
+ * only after completing all other relevant calls.
+ */
+bool torture_cleanup_begin(void)
+{
+ mutex_lock(&fullstop_mutex);
+ if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
+ pr_warn("Concurrent rmmod and shutdown illegal!\n");
+ mutex_unlock(&fullstop_mutex);
+ schedule_timeout_uninterruptible(10);
+ return true;
+ }
+ ACCESS_ONCE(fullstop) = FULLSTOP_RMMOD;
+ mutex_unlock(&fullstop_mutex);
+ torture_shutdown_cleanup();
+ torture_shuffle_cleanup();
+ torture_stutter_cleanup();
+ torture_onoff_cleanup();
+ return false;
+}
+EXPORT_SYMBOL_GPL(torture_cleanup_begin);
+
+void torture_cleanup_end(void)
+{
+ mutex_lock(&fullstop_mutex);
+ torture_type = NULL;
+ mutex_unlock(&fullstop_mutex);
+}
+EXPORT_SYMBOL_GPL(torture_cleanup_end);
+
+/*
+ * Is it time for the current torture test to stop?
+ */
+bool torture_must_stop(void)
+{
+ return torture_must_stop_irq() || kthread_should_stop();
+}
+EXPORT_SYMBOL_GPL(torture_must_stop);
+
+/*
+ * Is it time for the current torture test to stop? This is the irq-safe
+ * version, hence no check for kthread_should_stop().
+ */
+bool torture_must_stop_irq(void)
+{
+ return ACCESS_ONCE(fullstop) != FULLSTOP_DONTSTOP;
+}
+EXPORT_SYMBOL_GPL(torture_must_stop_irq);
+
+/*
+ * Each kthread must wait for kthread_should_stop() before returning from
+ * its top-level function, otherwise segfaults ensue. This function
+ * prints a "stopping" message and waits for kthread_should_stop(), and
+ * should be called from all torture kthreads immediately prior to
+ * returning.
+ */
+void torture_kthread_stopping(char *title)
+{
+ char buf[128];
+
+ snprintf(buf, sizeof(buf), "Stopping %s", title);
+ VERBOSE_TOROUT_STRING(buf);
+ while (!kthread_should_stop()) {
+ torture_shutdown_absorb(title);
+ schedule_timeout_uninterruptible(1);
+ }
+}
+EXPORT_SYMBOL_GPL(torture_kthread_stopping);
+
+/*
+ * Create a generic torture kthread that is immediately runnable. If you
+ * need the kthread to be stopped so that you can do something to it before
+ * 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)
+{
+ int ret = 0;
+
+ VERBOSE_TOROUT_STRING(m);
+ *tp = kthread_run(fn, arg, "%s", s);
+ if (IS_ERR(*tp)) {
+ ret = PTR_ERR(*tp);
+ VERBOSE_TOROUT_ERRSTRING(f);
+ *tp = NULL;
+ }
+ torture_shuffle_task_register(*tp);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(_torture_create_kthread);
+
+/*
+ * Stop a generic kthread, emitting a message.
+ */
+void _torture_stop_kthread(char *m, struct task_struct **tp)
+{
+ if (*tp == NULL)
+ return;
+ VERBOSE_TOROUT_STRING(m);
+ kthread_stop(*tp);
+ *tp = NULL;
+}
+EXPORT_SYMBOL_GPL(_torture_stop_kthread);
Code Review / kvmfornfv.git / blobdiff