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![Paul E. McKenney](/assets/img/avatar_default.png)
This commit moves cond_resched_rcu_qs() into stutter_wait(), saving a line and also avoiding RCU CPU stall warnings from all torture loops containing a stutter_wait(). Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
742 lines
20 KiB
C
742 lines
20 KiB
C
/*
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* Common functions for in-kernel torture tests.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, you can access it online at
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* http://www.gnu.org/licenses/gpl-2.0.html.
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*
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* Copyright (C) IBM Corporation, 2014
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*
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* Author: Paul E. McKenney <paulmck@us.ibm.com>
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* Based on kernel/rcu/torture.c.
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*/
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/kthread.h>
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#include <linux/err.h>
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#include <linux/spinlock.h>
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#include <linux/smp.h>
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#include <linux/interrupt.h>
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#include <linux/sched.h>
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#include <linux/atomic.h>
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#include <linux/bitops.h>
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#include <linux/completion.h>
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#include <linux/moduleparam.h>
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#include <linux/percpu.h>
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#include <linux/notifier.h>
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#include <linux/reboot.h>
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#include <linux/freezer.h>
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#include <linux/cpu.h>
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#include <linux/delay.h>
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#include <linux/stat.h>
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#include <linux/slab.h>
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#include <linux/trace_clock.h>
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#include <asm/byteorder.h>
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#include <linux/torture.h>
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>");
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static char *torture_type;
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static bool verbose;
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/* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */
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#define FULLSTOP_DONTSTOP 0 /* Normal operation. */
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#define FULLSTOP_SHUTDOWN 1 /* System shutdown with torture running. */
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#define FULLSTOP_RMMOD 2 /* Normal rmmod of torture. */
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static int fullstop = FULLSTOP_RMMOD;
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static DEFINE_MUTEX(fullstop_mutex);
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static int *torture_runnable;
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#ifdef CONFIG_HOTPLUG_CPU
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/*
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* Variables for online-offline handling. Only present if CPU hotplug
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* is enabled, otherwise does nothing.
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*/
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static struct task_struct *onoff_task;
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static long onoff_holdoff;
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static long onoff_interval;
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static long n_offline_attempts;
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static long n_offline_successes;
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static unsigned long sum_offline;
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static int min_offline = -1;
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static int max_offline;
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static long n_online_attempts;
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static long n_online_successes;
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static unsigned long sum_online;
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static int min_online = -1;
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static int max_online;
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/*
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* Execute random CPU-hotplug operations at the interval specified
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* by the onoff_interval.
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*/
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static int
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torture_onoff(void *arg)
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{
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int cpu;
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unsigned long delta;
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int maxcpu = -1;
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DEFINE_TORTURE_RANDOM(rand);
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int ret;
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unsigned long starttime;
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VERBOSE_TOROUT_STRING("torture_onoff task started");
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for_each_online_cpu(cpu)
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maxcpu = cpu;
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WARN_ON(maxcpu < 0);
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if (onoff_holdoff > 0) {
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VERBOSE_TOROUT_STRING("torture_onoff begin holdoff");
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schedule_timeout_interruptible(onoff_holdoff);
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VERBOSE_TOROUT_STRING("torture_onoff end holdoff");
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}
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while (!torture_must_stop()) {
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cpu = (torture_random(&rand) >> 4) % (maxcpu + 1);
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if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) {
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if (verbose)
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pr_alert("%s" TORTURE_FLAG
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"torture_onoff task: offlining %d\n",
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torture_type, cpu);
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starttime = jiffies;
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n_offline_attempts++;
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ret = cpu_down(cpu);
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if (ret) {
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if (verbose)
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pr_alert("%s" TORTURE_FLAG
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"torture_onoff task: offline %d failed: errno %d\n",
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torture_type, cpu, ret);
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} else {
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if (verbose)
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pr_alert("%s" TORTURE_FLAG
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"torture_onoff task: offlined %d\n",
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torture_type, cpu);
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n_offline_successes++;
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delta = jiffies - starttime;
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sum_offline += delta;
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if (min_offline < 0) {
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min_offline = delta;
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max_offline = delta;
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}
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if (min_offline > delta)
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min_offline = delta;
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if (max_offline < delta)
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max_offline = delta;
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}
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} else if (cpu_is_hotpluggable(cpu)) {
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if (verbose)
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pr_alert("%s" TORTURE_FLAG
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"torture_onoff task: onlining %d\n",
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torture_type, cpu);
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starttime = jiffies;
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n_online_attempts++;
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ret = cpu_up(cpu);
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if (ret) {
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if (verbose)
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pr_alert("%s" TORTURE_FLAG
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"torture_onoff task: online %d failed: errno %d\n",
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torture_type, cpu, ret);
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} else {
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if (verbose)
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pr_alert("%s" TORTURE_FLAG
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"torture_onoff task: onlined %d\n",
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torture_type, cpu);
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n_online_successes++;
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delta = jiffies - starttime;
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sum_online += delta;
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if (min_online < 0) {
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min_online = delta;
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max_online = delta;
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}
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if (min_online > delta)
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min_online = delta;
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if (max_online < delta)
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max_online = delta;
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}
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}
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schedule_timeout_interruptible(onoff_interval);
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}
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torture_kthread_stopping("torture_onoff");
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return 0;
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}
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#endif /* #ifdef CONFIG_HOTPLUG_CPU */
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/*
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* Initiate online-offline handling.
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*/
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int torture_onoff_init(long ooholdoff, long oointerval)
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{
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int ret = 0;
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#ifdef CONFIG_HOTPLUG_CPU
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onoff_holdoff = ooholdoff;
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onoff_interval = oointerval;
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if (onoff_interval <= 0)
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return 0;
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ret = torture_create_kthread(torture_onoff, NULL, onoff_task);
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#endif /* #ifdef CONFIG_HOTPLUG_CPU */
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return ret;
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}
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EXPORT_SYMBOL_GPL(torture_onoff_init);
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/*
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* Clean up after online/offline testing.
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*/
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static void torture_onoff_cleanup(void)
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{
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#ifdef CONFIG_HOTPLUG_CPU
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if (onoff_task == NULL)
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return;
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VERBOSE_TOROUT_STRING("Stopping torture_onoff task");
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kthread_stop(onoff_task);
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onoff_task = NULL;
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#endif /* #ifdef CONFIG_HOTPLUG_CPU */
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}
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EXPORT_SYMBOL_GPL(torture_onoff_cleanup);
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/*
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* Print online/offline testing statistics.
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*/
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void torture_onoff_stats(void)
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{
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#ifdef CONFIG_HOTPLUG_CPU
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pr_cont("onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
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n_online_successes, n_online_attempts,
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n_offline_successes, n_offline_attempts,
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min_online, max_online,
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min_offline, max_offline,
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sum_online, sum_offline, HZ);
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#endif /* #ifdef CONFIG_HOTPLUG_CPU */
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}
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EXPORT_SYMBOL_GPL(torture_onoff_stats);
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/*
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* Were all the online/offline operations successful?
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*/
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bool torture_onoff_failures(void)
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{
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#ifdef CONFIG_HOTPLUG_CPU
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return n_online_successes != n_online_attempts ||
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n_offline_successes != n_offline_attempts;
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#else /* #ifdef CONFIG_HOTPLUG_CPU */
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return false;
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#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
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}
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EXPORT_SYMBOL_GPL(torture_onoff_failures);
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#define TORTURE_RANDOM_MULT 39916801 /* prime */
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#define TORTURE_RANDOM_ADD 479001701 /* prime */
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#define TORTURE_RANDOM_REFRESH 10000
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/*
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* Crude but fast random-number generator. Uses a linear congruential
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* generator, with occasional help from cpu_clock().
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*/
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unsigned long
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torture_random(struct torture_random_state *trsp)
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{
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if (--trsp->trs_count < 0) {
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trsp->trs_state += (unsigned long)local_clock();
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trsp->trs_count = TORTURE_RANDOM_REFRESH;
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}
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trsp->trs_state = trsp->trs_state * TORTURE_RANDOM_MULT +
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TORTURE_RANDOM_ADD;
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return swahw32(trsp->trs_state);
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}
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EXPORT_SYMBOL_GPL(torture_random);
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/*
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* Variables for shuffling. The idea is to ensure that each CPU stays
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* idle for an extended period to test interactions with dyntick idle,
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* as well as interactions with any per-CPU varibles.
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*/
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struct shuffle_task {
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struct list_head st_l;
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struct task_struct *st_t;
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};
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static long shuffle_interval; /* In jiffies. */
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static struct task_struct *shuffler_task;
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static cpumask_var_t shuffle_tmp_mask;
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static int shuffle_idle_cpu; /* Force all torture tasks off this CPU */
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static struct list_head shuffle_task_list = LIST_HEAD_INIT(shuffle_task_list);
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static DEFINE_MUTEX(shuffle_task_mutex);
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/*
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* Register a task to be shuffled. If there is no memory, just splat
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* and don't bother registering.
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*/
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void torture_shuffle_task_register(struct task_struct *tp)
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{
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struct shuffle_task *stp;
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if (WARN_ON_ONCE(tp == NULL))
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return;
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stp = kmalloc(sizeof(*stp), GFP_KERNEL);
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if (WARN_ON_ONCE(stp == NULL))
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return;
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stp->st_t = tp;
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mutex_lock(&shuffle_task_mutex);
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list_add(&stp->st_l, &shuffle_task_list);
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mutex_unlock(&shuffle_task_mutex);
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}
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EXPORT_SYMBOL_GPL(torture_shuffle_task_register);
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/*
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* Unregister all tasks, for example, at the end of the torture run.
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*/
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static void torture_shuffle_task_unregister_all(void)
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{
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struct shuffle_task *stp;
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struct shuffle_task *p;
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mutex_lock(&shuffle_task_mutex);
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list_for_each_entry_safe(stp, p, &shuffle_task_list, st_l) {
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list_del(&stp->st_l);
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kfree(stp);
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}
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mutex_unlock(&shuffle_task_mutex);
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}
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/* Shuffle tasks such that we allow shuffle_idle_cpu to become idle.
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* A special case is when shuffle_idle_cpu = -1, in which case we allow
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* the tasks to run on all CPUs.
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*/
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static void torture_shuffle_tasks(void)
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{
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struct shuffle_task *stp;
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cpumask_setall(shuffle_tmp_mask);
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get_online_cpus();
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/* No point in shuffling if there is only one online CPU (ex: UP) */
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if (num_online_cpus() == 1) {
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put_online_cpus();
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return;
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}
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/* Advance to the next CPU. Upon overflow, don't idle any CPUs. */
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shuffle_idle_cpu = cpumask_next(shuffle_idle_cpu, shuffle_tmp_mask);
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if (shuffle_idle_cpu >= nr_cpu_ids)
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shuffle_idle_cpu = -1;
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else
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cpumask_clear_cpu(shuffle_idle_cpu, shuffle_tmp_mask);
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mutex_lock(&shuffle_task_mutex);
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list_for_each_entry(stp, &shuffle_task_list, st_l)
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set_cpus_allowed_ptr(stp->st_t, shuffle_tmp_mask);
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mutex_unlock(&shuffle_task_mutex);
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put_online_cpus();
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}
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/* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
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* system to become idle at a time and cut off its timer ticks. This is meant
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* to test the support for such tickless idle CPU in RCU.
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*/
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static int torture_shuffle(void *arg)
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{
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VERBOSE_TOROUT_STRING("torture_shuffle task started");
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do {
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schedule_timeout_interruptible(shuffle_interval);
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torture_shuffle_tasks();
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torture_shutdown_absorb("torture_shuffle");
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} while (!torture_must_stop());
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torture_kthread_stopping("torture_shuffle");
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return 0;
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}
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/*
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* Start the shuffler, with shuffint in jiffies.
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*/
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int torture_shuffle_init(long shuffint)
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{
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shuffle_interval = shuffint;
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shuffle_idle_cpu = -1;
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if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
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VERBOSE_TOROUT_ERRSTRING("Failed to alloc mask");
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return -ENOMEM;
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}
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/* Create the shuffler thread */
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return torture_create_kthread(torture_shuffle, NULL, shuffler_task);
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}
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EXPORT_SYMBOL_GPL(torture_shuffle_init);
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/*
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* Stop the shuffling.
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*/
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static void torture_shuffle_cleanup(void)
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{
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torture_shuffle_task_unregister_all();
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if (shuffler_task) {
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VERBOSE_TOROUT_STRING("Stopping torture_shuffle task");
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kthread_stop(shuffler_task);
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free_cpumask_var(shuffle_tmp_mask);
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}
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shuffler_task = NULL;
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}
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EXPORT_SYMBOL_GPL(torture_shuffle_cleanup);
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/*
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* Variables for auto-shutdown. This allows "lights out" torture runs
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* to be fully scripted.
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*/
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static int shutdown_secs; /* desired test duration in seconds. */
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static struct task_struct *shutdown_task;
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static unsigned long shutdown_time; /* jiffies to system shutdown. */
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static void (*torture_shutdown_hook)(void);
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/*
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* Absorb kthreads into a kernel function that won't return, so that
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* they won't ever access module text or data again.
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*/
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void torture_shutdown_absorb(const char *title)
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{
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while (READ_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
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pr_notice("torture thread %s parking due to system shutdown\n",
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title);
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schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
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}
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}
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EXPORT_SYMBOL_GPL(torture_shutdown_absorb);
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/*
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* Cause the torture test to shutdown the system after the test has
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* run for the time specified by the shutdown_secs parameter.
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*/
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static int torture_shutdown(void *arg)
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{
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long delta;
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unsigned long jiffies_snap;
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VERBOSE_TOROUT_STRING("torture_shutdown task started");
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jiffies_snap = jiffies;
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while (ULONG_CMP_LT(jiffies_snap, shutdown_time) &&
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!torture_must_stop()) {
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delta = shutdown_time - jiffies_snap;
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if (verbose)
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pr_alert("%s" TORTURE_FLAG
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"torture_shutdown task: %lu jiffies remaining\n",
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torture_type, delta);
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schedule_timeout_interruptible(delta);
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jiffies_snap = jiffies;
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}
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if (torture_must_stop()) {
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torture_kthread_stopping("torture_shutdown");
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return 0;
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}
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/* OK, shut down the system. */
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VERBOSE_TOROUT_STRING("torture_shutdown task shutting down system");
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shutdown_task = NULL; /* Avoid self-kill deadlock. */
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if (torture_shutdown_hook)
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torture_shutdown_hook();
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else
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VERBOSE_TOROUT_STRING("No torture_shutdown_hook(), skipping.");
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kernel_power_off(); /* Shut down the system. */
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return 0;
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}
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/*
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* Start up the shutdown task.
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*/
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int torture_shutdown_init(int ssecs, void (*cleanup)(void))
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{
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int ret = 0;
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shutdown_secs = ssecs;
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torture_shutdown_hook = cleanup;
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if (shutdown_secs > 0) {
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shutdown_time = jiffies + shutdown_secs * HZ;
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ret = torture_create_kthread(torture_shutdown, NULL,
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shutdown_task);
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}
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return ret;
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}
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EXPORT_SYMBOL_GPL(torture_shutdown_init);
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/*
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* Detect and respond to a system shutdown.
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*/
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static int torture_shutdown_notify(struct notifier_block *unused1,
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unsigned long unused2, void *unused3)
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{
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mutex_lock(&fullstop_mutex);
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if (READ_ONCE(fullstop) == FULLSTOP_DONTSTOP) {
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VERBOSE_TOROUT_STRING("Unscheduled system shutdown detected");
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WRITE_ONCE(fullstop, FULLSTOP_SHUTDOWN);
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} else {
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pr_warn("Concurrent rmmod and shutdown illegal!\n");
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}
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mutex_unlock(&fullstop_mutex);
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return NOTIFY_DONE;
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}
|
|
|
|
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)
|
|
{
|
|
cond_resched_rcu_qs();
|
|
while (READ_ONCE(stutter_pause_test) ||
|
|
(torture_runnable && !READ_ONCE(*torture_runnable))) {
|
|
if (stutter_pause_test)
|
|
if (READ_ONCE(stutter_pause_test) == 1)
|
|
schedule_timeout_interruptible(1);
|
|
else
|
|
while (READ_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);
|
|
WRITE_ONCE(stutter_pause_test, 2);
|
|
}
|
|
schedule_timeout_interruptible(1);
|
|
WRITE_ONCE(stutter_pause_test, 1);
|
|
}
|
|
if (!torture_must_stop())
|
|
schedule_timeout_interruptible(stutter);
|
|
WRITE_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 (READ_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
|
|
pr_warn("Concurrent rmmod and shutdown illegal!\n");
|
|
mutex_unlock(&fullstop_mutex);
|
|
schedule_timeout_uninterruptible(10);
|
|
return true;
|
|
}
|
|
WRITE_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 READ_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);
|