![Wolfgang M. Reimer](/assets/img/avatar_default.png)
Including rwlock.h directly will cause kernel builds to fail if CONFIG_PREEMPT_RT is defined. The correct header file (rwlock_rt.h OR rwlock.h) will be included by spinlock.h which is included by locktorture.c anyway. Remove the include of linux/rwlock.h. Signed-off-by: Wolfgang M. Reimer <linuxball@gmail.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
1051 lines
28 KiB
C
1051 lines
28 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* Module-based torture test facility for locking
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*
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* Copyright (C) IBM Corporation, 2014
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*
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* Authors: Paul E. McKenney <paulmck@linux.ibm.com>
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* Davidlohr Bueso <dave@stgolabs.net>
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* Based on kernel/rcu/torture.c.
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*/
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#define pr_fmt(fmt) fmt
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/kthread.h>
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#include <linux/sched/rt.h>
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#include <linux/spinlock.h>
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#include <linux/mutex.h>
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#include <linux/rwsem.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 <uapi/linux/sched/types.h>
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#include <linux/rtmutex.h>
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#include <linux/atomic.h>
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#include <linux/moduleparam.h>
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#include <linux/delay.h>
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#include <linux/slab.h>
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#include <linux/percpu-rwsem.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@linux.ibm.com>");
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torture_param(int, nwriters_stress, -1,
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"Number of write-locking stress-test threads");
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torture_param(int, nreaders_stress, -1,
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"Number of read-locking stress-test threads");
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torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)");
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torture_param(int, onoff_interval, 0,
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"Time between CPU hotplugs (s), 0=disable");
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torture_param(int, shuffle_interval, 3,
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"Number of jiffies between shuffles, 0=disable");
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torture_param(int, shutdown_secs, 0, "Shutdown time (j), <= zero to disable.");
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torture_param(int, stat_interval, 60,
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"Number of seconds between stats printk()s");
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torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable");
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torture_param(int, verbose, 1,
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"Enable verbose debugging printk()s");
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static char *torture_type = "spin_lock";
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module_param(torture_type, charp, 0444);
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MODULE_PARM_DESC(torture_type,
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"Type of lock to torture (spin_lock, spin_lock_irq, mutex_lock, ...)");
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static struct task_struct *stats_task;
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static struct task_struct **writer_tasks;
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static struct task_struct **reader_tasks;
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static bool lock_is_write_held;
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static bool lock_is_read_held;
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struct lock_stress_stats {
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long n_lock_fail;
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long n_lock_acquired;
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};
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/* Forward reference. */
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static void lock_torture_cleanup(void);
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/*
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* Operations vector for selecting different types of tests.
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*/
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struct lock_torture_ops {
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void (*init)(void);
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int (*writelock)(void);
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void (*write_delay)(struct torture_random_state *trsp);
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void (*task_boost)(struct torture_random_state *trsp);
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void (*writeunlock)(void);
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int (*readlock)(void);
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void (*read_delay)(struct torture_random_state *trsp);
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void (*readunlock)(void);
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unsigned long flags; /* for irq spinlocks */
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const char *name;
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};
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struct lock_torture_cxt {
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int nrealwriters_stress;
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int nrealreaders_stress;
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bool debug_lock;
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atomic_t n_lock_torture_errors;
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struct lock_torture_ops *cur_ops;
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struct lock_stress_stats *lwsa; /* writer statistics */
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struct lock_stress_stats *lrsa; /* reader statistics */
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};
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static struct lock_torture_cxt cxt = { 0, 0, false,
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ATOMIC_INIT(0),
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NULL, NULL};
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/*
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* Definitions for lock torture testing.
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*/
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static int torture_lock_busted_write_lock(void)
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{
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return 0; /* BUGGY, do not use in real life!!! */
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}
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static void torture_lock_busted_write_delay(struct torture_random_state *trsp)
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{
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const unsigned long longdelay_ms = 100;
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/* We want a long delay occasionally to force massive contention. */
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if (!(torture_random(trsp) %
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(cxt.nrealwriters_stress * 2000 * longdelay_ms)))
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mdelay(longdelay_ms);
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if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))
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torture_preempt_schedule(); /* Allow test to be preempted. */
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}
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static void torture_lock_busted_write_unlock(void)
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{
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/* BUGGY, do not use in real life!!! */
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}
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static void torture_boost_dummy(struct torture_random_state *trsp)
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{
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/* Only rtmutexes care about priority */
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}
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static struct lock_torture_ops lock_busted_ops = {
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.writelock = torture_lock_busted_write_lock,
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.write_delay = torture_lock_busted_write_delay,
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.task_boost = torture_boost_dummy,
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.writeunlock = torture_lock_busted_write_unlock,
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.readlock = NULL,
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.read_delay = NULL,
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.readunlock = NULL,
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.name = "lock_busted"
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};
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static DEFINE_SPINLOCK(torture_spinlock);
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static int torture_spin_lock_write_lock(void) __acquires(torture_spinlock)
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{
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spin_lock(&torture_spinlock);
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return 0;
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}
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static void torture_spin_lock_write_delay(struct torture_random_state *trsp)
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{
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const unsigned long shortdelay_us = 2;
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const unsigned long longdelay_ms = 100;
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/* We want a short delay mostly to emulate likely code, and
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* we want a long delay occasionally to force massive contention.
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*/
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if (!(torture_random(trsp) %
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(cxt.nrealwriters_stress * 2000 * longdelay_ms)))
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mdelay(longdelay_ms);
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if (!(torture_random(trsp) %
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(cxt.nrealwriters_stress * 2 * shortdelay_us)))
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udelay(shortdelay_us);
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if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))
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torture_preempt_schedule(); /* Allow test to be preempted. */
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}
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static void torture_spin_lock_write_unlock(void) __releases(torture_spinlock)
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{
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spin_unlock(&torture_spinlock);
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}
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static struct lock_torture_ops spin_lock_ops = {
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.writelock = torture_spin_lock_write_lock,
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.write_delay = torture_spin_lock_write_delay,
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.task_boost = torture_boost_dummy,
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.writeunlock = torture_spin_lock_write_unlock,
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.readlock = NULL,
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.read_delay = NULL,
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.readunlock = NULL,
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.name = "spin_lock"
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};
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static int torture_spin_lock_write_lock_irq(void)
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__acquires(torture_spinlock)
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{
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unsigned long flags;
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spin_lock_irqsave(&torture_spinlock, flags);
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cxt.cur_ops->flags = flags;
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return 0;
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}
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static void torture_lock_spin_write_unlock_irq(void)
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__releases(torture_spinlock)
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{
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spin_unlock_irqrestore(&torture_spinlock, cxt.cur_ops->flags);
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}
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static struct lock_torture_ops spin_lock_irq_ops = {
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.writelock = torture_spin_lock_write_lock_irq,
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.write_delay = torture_spin_lock_write_delay,
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.task_boost = torture_boost_dummy,
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.writeunlock = torture_lock_spin_write_unlock_irq,
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.readlock = NULL,
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.read_delay = NULL,
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.readunlock = NULL,
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.name = "spin_lock_irq"
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};
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static DEFINE_RWLOCK(torture_rwlock);
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static int torture_rwlock_write_lock(void) __acquires(torture_rwlock)
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{
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write_lock(&torture_rwlock);
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return 0;
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}
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static void torture_rwlock_write_delay(struct torture_random_state *trsp)
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{
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const unsigned long shortdelay_us = 2;
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const unsigned long longdelay_ms = 100;
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/* We want a short delay mostly to emulate likely code, and
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* we want a long delay occasionally to force massive contention.
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*/
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if (!(torture_random(trsp) %
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(cxt.nrealwriters_stress * 2000 * longdelay_ms)))
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mdelay(longdelay_ms);
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else
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udelay(shortdelay_us);
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}
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static void torture_rwlock_write_unlock(void) __releases(torture_rwlock)
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{
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write_unlock(&torture_rwlock);
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}
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static int torture_rwlock_read_lock(void) __acquires(torture_rwlock)
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{
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read_lock(&torture_rwlock);
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return 0;
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}
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static void torture_rwlock_read_delay(struct torture_random_state *trsp)
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{
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const unsigned long shortdelay_us = 10;
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const unsigned long longdelay_ms = 100;
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/* We want a short delay mostly to emulate likely code, and
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* we want a long delay occasionally to force massive contention.
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*/
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if (!(torture_random(trsp) %
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(cxt.nrealreaders_stress * 2000 * longdelay_ms)))
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mdelay(longdelay_ms);
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else
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udelay(shortdelay_us);
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}
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static void torture_rwlock_read_unlock(void) __releases(torture_rwlock)
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{
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read_unlock(&torture_rwlock);
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}
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static struct lock_torture_ops rw_lock_ops = {
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.writelock = torture_rwlock_write_lock,
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.write_delay = torture_rwlock_write_delay,
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.task_boost = torture_boost_dummy,
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.writeunlock = torture_rwlock_write_unlock,
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.readlock = torture_rwlock_read_lock,
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.read_delay = torture_rwlock_read_delay,
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.readunlock = torture_rwlock_read_unlock,
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.name = "rw_lock"
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};
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static int torture_rwlock_write_lock_irq(void) __acquires(torture_rwlock)
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{
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unsigned long flags;
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write_lock_irqsave(&torture_rwlock, flags);
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cxt.cur_ops->flags = flags;
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return 0;
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}
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static void torture_rwlock_write_unlock_irq(void)
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__releases(torture_rwlock)
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{
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write_unlock_irqrestore(&torture_rwlock, cxt.cur_ops->flags);
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}
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static int torture_rwlock_read_lock_irq(void) __acquires(torture_rwlock)
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{
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unsigned long flags;
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read_lock_irqsave(&torture_rwlock, flags);
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cxt.cur_ops->flags = flags;
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return 0;
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}
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static void torture_rwlock_read_unlock_irq(void)
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__releases(torture_rwlock)
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{
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read_unlock_irqrestore(&torture_rwlock, cxt.cur_ops->flags);
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}
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static struct lock_torture_ops rw_lock_irq_ops = {
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.writelock = torture_rwlock_write_lock_irq,
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.write_delay = torture_rwlock_write_delay,
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.task_boost = torture_boost_dummy,
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.writeunlock = torture_rwlock_write_unlock_irq,
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.readlock = torture_rwlock_read_lock_irq,
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.read_delay = torture_rwlock_read_delay,
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.readunlock = torture_rwlock_read_unlock_irq,
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.name = "rw_lock_irq"
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};
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static DEFINE_MUTEX(torture_mutex);
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static int torture_mutex_lock(void) __acquires(torture_mutex)
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{
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mutex_lock(&torture_mutex);
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return 0;
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}
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static void torture_mutex_delay(struct torture_random_state *trsp)
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{
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const unsigned long longdelay_ms = 100;
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/* We want a long delay occasionally to force massive contention. */
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if (!(torture_random(trsp) %
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(cxt.nrealwriters_stress * 2000 * longdelay_ms)))
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mdelay(longdelay_ms * 5);
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else
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mdelay(longdelay_ms / 5);
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if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))
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torture_preempt_schedule(); /* Allow test to be preempted. */
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}
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static void torture_mutex_unlock(void) __releases(torture_mutex)
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{
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mutex_unlock(&torture_mutex);
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}
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static struct lock_torture_ops mutex_lock_ops = {
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.writelock = torture_mutex_lock,
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.write_delay = torture_mutex_delay,
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.task_boost = torture_boost_dummy,
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.writeunlock = torture_mutex_unlock,
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.readlock = NULL,
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.read_delay = NULL,
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.readunlock = NULL,
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.name = "mutex_lock"
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};
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#include <linux/ww_mutex.h>
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static DEFINE_WD_CLASS(torture_ww_class);
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static DEFINE_WW_MUTEX(torture_ww_mutex_0, &torture_ww_class);
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static DEFINE_WW_MUTEX(torture_ww_mutex_1, &torture_ww_class);
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static DEFINE_WW_MUTEX(torture_ww_mutex_2, &torture_ww_class);
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static int torture_ww_mutex_lock(void)
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__acquires(torture_ww_mutex_0)
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__acquires(torture_ww_mutex_1)
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__acquires(torture_ww_mutex_2)
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{
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LIST_HEAD(list);
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struct reorder_lock {
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struct list_head link;
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struct ww_mutex *lock;
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} locks[3], *ll, *ln;
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struct ww_acquire_ctx ctx;
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locks[0].lock = &torture_ww_mutex_0;
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list_add(&locks[0].link, &list);
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locks[1].lock = &torture_ww_mutex_1;
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list_add(&locks[1].link, &list);
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locks[2].lock = &torture_ww_mutex_2;
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list_add(&locks[2].link, &list);
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ww_acquire_init(&ctx, &torture_ww_class);
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list_for_each_entry(ll, &list, link) {
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int err;
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err = ww_mutex_lock(ll->lock, &ctx);
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if (!err)
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continue;
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ln = ll;
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list_for_each_entry_continue_reverse(ln, &list, link)
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ww_mutex_unlock(ln->lock);
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if (err != -EDEADLK)
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return err;
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ww_mutex_lock_slow(ll->lock, &ctx);
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list_move(&ll->link, &list);
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}
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ww_acquire_fini(&ctx);
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return 0;
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}
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static void torture_ww_mutex_unlock(void)
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__releases(torture_ww_mutex_0)
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__releases(torture_ww_mutex_1)
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__releases(torture_ww_mutex_2)
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{
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ww_mutex_unlock(&torture_ww_mutex_0);
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ww_mutex_unlock(&torture_ww_mutex_1);
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ww_mutex_unlock(&torture_ww_mutex_2);
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}
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static struct lock_torture_ops ww_mutex_lock_ops = {
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.writelock = torture_ww_mutex_lock,
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.write_delay = torture_mutex_delay,
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.task_boost = torture_boost_dummy,
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.writeunlock = torture_ww_mutex_unlock,
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.readlock = NULL,
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.read_delay = NULL,
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.readunlock = NULL,
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.name = "ww_mutex_lock"
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};
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#ifdef CONFIG_RT_MUTEXES
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static DEFINE_RT_MUTEX(torture_rtmutex);
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static int torture_rtmutex_lock(void) __acquires(torture_rtmutex)
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{
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rt_mutex_lock(&torture_rtmutex);
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return 0;
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}
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static void torture_rtmutex_boost(struct torture_random_state *trsp)
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{
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int policy;
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struct sched_param param;
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const unsigned int factor = 50000; /* yes, quite arbitrary */
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if (!rt_task(current)) {
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/*
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* Boost priority once every ~50k operations. When the
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* task tries to take the lock, the rtmutex it will account
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* for the new priority, and do any corresponding pi-dance.
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*/
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if (trsp && !(torture_random(trsp) %
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(cxt.nrealwriters_stress * factor))) {
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policy = SCHED_FIFO;
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param.sched_priority = MAX_RT_PRIO - 1;
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} else /* common case, do nothing */
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return;
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} else {
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/*
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* The task will remain boosted for another ~500k operations,
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* then restored back to its original prio, and so forth.
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*
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* When @trsp is nil, we want to force-reset the task for
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* stopping the kthread.
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*/
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if (!trsp || !(torture_random(trsp) %
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(cxt.nrealwriters_stress * factor * 2))) {
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policy = SCHED_NORMAL;
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param.sched_priority = 0;
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} else /* common case, do nothing */
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return;
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}
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sched_setscheduler_nocheck(current, policy, ¶m);
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}
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static void torture_rtmutex_delay(struct torture_random_state *trsp)
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{
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const unsigned long shortdelay_us = 2;
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const unsigned long longdelay_ms = 100;
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/*
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* We want a short delay mostly to emulate likely code, and
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* we want a long delay occasionally to force massive contention.
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*/
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if (!(torture_random(trsp) %
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(cxt.nrealwriters_stress * 2000 * longdelay_ms)))
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mdelay(longdelay_ms);
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if (!(torture_random(trsp) %
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(cxt.nrealwriters_stress * 2 * shortdelay_us)))
|
|
udelay(shortdelay_us);
|
|
if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))
|
|
torture_preempt_schedule(); /* Allow test to be preempted. */
|
|
}
|
|
|
|
static void torture_rtmutex_unlock(void) __releases(torture_rtmutex)
|
|
{
|
|
rt_mutex_unlock(&torture_rtmutex);
|
|
}
|
|
|
|
static struct lock_torture_ops rtmutex_lock_ops = {
|
|
.writelock = torture_rtmutex_lock,
|
|
.write_delay = torture_rtmutex_delay,
|
|
.task_boost = torture_rtmutex_boost,
|
|
.writeunlock = torture_rtmutex_unlock,
|
|
.readlock = NULL,
|
|
.read_delay = NULL,
|
|
.readunlock = NULL,
|
|
.name = "rtmutex_lock"
|
|
};
|
|
#endif
|
|
|
|
static DECLARE_RWSEM(torture_rwsem);
|
|
static int torture_rwsem_down_write(void) __acquires(torture_rwsem)
|
|
{
|
|
down_write(&torture_rwsem);
|
|
return 0;
|
|
}
|
|
|
|
static void torture_rwsem_write_delay(struct torture_random_state *trsp)
|
|
{
|
|
const unsigned long longdelay_ms = 100;
|
|
|
|
/* We want a long delay occasionally to force massive contention. */
|
|
if (!(torture_random(trsp) %
|
|
(cxt.nrealwriters_stress * 2000 * longdelay_ms)))
|
|
mdelay(longdelay_ms * 10);
|
|
else
|
|
mdelay(longdelay_ms / 10);
|
|
if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000)))
|
|
torture_preempt_schedule(); /* Allow test to be preempted. */
|
|
}
|
|
|
|
static void torture_rwsem_up_write(void) __releases(torture_rwsem)
|
|
{
|
|
up_write(&torture_rwsem);
|
|
}
|
|
|
|
static int torture_rwsem_down_read(void) __acquires(torture_rwsem)
|
|
{
|
|
down_read(&torture_rwsem);
|
|
return 0;
|
|
}
|
|
|
|
static void torture_rwsem_read_delay(struct torture_random_state *trsp)
|
|
{
|
|
const unsigned long longdelay_ms = 100;
|
|
|
|
/* We want a long delay occasionally to force massive contention. */
|
|
if (!(torture_random(trsp) %
|
|
(cxt.nrealreaders_stress * 2000 * longdelay_ms)))
|
|
mdelay(longdelay_ms * 2);
|
|
else
|
|
mdelay(longdelay_ms / 2);
|
|
if (!(torture_random(trsp) % (cxt.nrealreaders_stress * 20000)))
|
|
torture_preempt_schedule(); /* Allow test to be preempted. */
|
|
}
|
|
|
|
static void torture_rwsem_up_read(void) __releases(torture_rwsem)
|
|
{
|
|
up_read(&torture_rwsem);
|
|
}
|
|
|
|
static struct lock_torture_ops rwsem_lock_ops = {
|
|
.writelock = torture_rwsem_down_write,
|
|
.write_delay = torture_rwsem_write_delay,
|
|
.task_boost = torture_boost_dummy,
|
|
.writeunlock = torture_rwsem_up_write,
|
|
.readlock = torture_rwsem_down_read,
|
|
.read_delay = torture_rwsem_read_delay,
|
|
.readunlock = torture_rwsem_up_read,
|
|
.name = "rwsem_lock"
|
|
};
|
|
|
|
#include <linux/percpu-rwsem.h>
|
|
static struct percpu_rw_semaphore pcpu_rwsem;
|
|
|
|
void torture_percpu_rwsem_init(void)
|
|
{
|
|
BUG_ON(percpu_init_rwsem(&pcpu_rwsem));
|
|
}
|
|
|
|
static int torture_percpu_rwsem_down_write(void) __acquires(pcpu_rwsem)
|
|
{
|
|
percpu_down_write(&pcpu_rwsem);
|
|
return 0;
|
|
}
|
|
|
|
static void torture_percpu_rwsem_up_write(void) __releases(pcpu_rwsem)
|
|
{
|
|
percpu_up_write(&pcpu_rwsem);
|
|
}
|
|
|
|
static int torture_percpu_rwsem_down_read(void) __acquires(pcpu_rwsem)
|
|
{
|
|
percpu_down_read(&pcpu_rwsem);
|
|
return 0;
|
|
}
|
|
|
|
static void torture_percpu_rwsem_up_read(void) __releases(pcpu_rwsem)
|
|
{
|
|
percpu_up_read(&pcpu_rwsem);
|
|
}
|
|
|
|
static struct lock_torture_ops percpu_rwsem_lock_ops = {
|
|
.init = torture_percpu_rwsem_init,
|
|
.writelock = torture_percpu_rwsem_down_write,
|
|
.write_delay = torture_rwsem_write_delay,
|
|
.task_boost = torture_boost_dummy,
|
|
.writeunlock = torture_percpu_rwsem_up_write,
|
|
.readlock = torture_percpu_rwsem_down_read,
|
|
.read_delay = torture_rwsem_read_delay,
|
|
.readunlock = torture_percpu_rwsem_up_read,
|
|
.name = "percpu_rwsem_lock"
|
|
};
|
|
|
|
/*
|
|
* Lock torture writer kthread. Repeatedly acquires and releases
|
|
* the lock, checking for duplicate acquisitions.
|
|
*/
|
|
static int lock_torture_writer(void *arg)
|
|
{
|
|
struct lock_stress_stats *lwsp = arg;
|
|
static DEFINE_TORTURE_RANDOM(rand);
|
|
|
|
VERBOSE_TOROUT_STRING("lock_torture_writer task started");
|
|
set_user_nice(current, MAX_NICE);
|
|
|
|
do {
|
|
if ((torture_random(&rand) & 0xfffff) == 0)
|
|
schedule_timeout_uninterruptible(1);
|
|
|
|
cxt.cur_ops->task_boost(&rand);
|
|
cxt.cur_ops->writelock();
|
|
if (WARN_ON_ONCE(lock_is_write_held))
|
|
lwsp->n_lock_fail++;
|
|
lock_is_write_held = 1;
|
|
if (WARN_ON_ONCE(lock_is_read_held))
|
|
lwsp->n_lock_fail++; /* rare, but... */
|
|
|
|
lwsp->n_lock_acquired++;
|
|
cxt.cur_ops->write_delay(&rand);
|
|
lock_is_write_held = 0;
|
|
cxt.cur_ops->writeunlock();
|
|
|
|
stutter_wait("lock_torture_writer");
|
|
} while (!torture_must_stop());
|
|
|
|
cxt.cur_ops->task_boost(NULL); /* reset prio */
|
|
torture_kthread_stopping("lock_torture_writer");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Lock torture reader kthread. Repeatedly acquires and releases
|
|
* the reader lock.
|
|
*/
|
|
static int lock_torture_reader(void *arg)
|
|
{
|
|
struct lock_stress_stats *lrsp = arg;
|
|
static DEFINE_TORTURE_RANDOM(rand);
|
|
|
|
VERBOSE_TOROUT_STRING("lock_torture_reader task started");
|
|
set_user_nice(current, MAX_NICE);
|
|
|
|
do {
|
|
if ((torture_random(&rand) & 0xfffff) == 0)
|
|
schedule_timeout_uninterruptible(1);
|
|
|
|
cxt.cur_ops->readlock();
|
|
lock_is_read_held = 1;
|
|
if (WARN_ON_ONCE(lock_is_write_held))
|
|
lrsp->n_lock_fail++; /* rare, but... */
|
|
|
|
lrsp->n_lock_acquired++;
|
|
cxt.cur_ops->read_delay(&rand);
|
|
lock_is_read_held = 0;
|
|
cxt.cur_ops->readunlock();
|
|
|
|
stutter_wait("lock_torture_reader");
|
|
} while (!torture_must_stop());
|
|
torture_kthread_stopping("lock_torture_reader");
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Create an lock-torture-statistics message in the specified buffer.
|
|
*/
|
|
static void __torture_print_stats(char *page,
|
|
struct lock_stress_stats *statp, bool write)
|
|
{
|
|
bool fail = 0;
|
|
int i, n_stress;
|
|
long max = 0, min = statp ? statp[0].n_lock_acquired : 0;
|
|
long long sum = 0;
|
|
|
|
n_stress = write ? cxt.nrealwriters_stress : cxt.nrealreaders_stress;
|
|
for (i = 0; i < n_stress; i++) {
|
|
if (statp[i].n_lock_fail)
|
|
fail = true;
|
|
sum += statp[i].n_lock_acquired;
|
|
if (max < statp[i].n_lock_fail)
|
|
max = statp[i].n_lock_fail;
|
|
if (min > statp[i].n_lock_fail)
|
|
min = statp[i].n_lock_fail;
|
|
}
|
|
page += sprintf(page,
|
|
"%s: Total: %lld Max/Min: %ld/%ld %s Fail: %d %s\n",
|
|
write ? "Writes" : "Reads ",
|
|
sum, max, min, max / 2 > min ? "???" : "",
|
|
fail, fail ? "!!!" : "");
|
|
if (fail)
|
|
atomic_inc(&cxt.n_lock_torture_errors);
|
|
}
|
|
|
|
/*
|
|
* Print torture statistics. Caller must ensure that there is only one
|
|
* call to this function at a given time!!! This is normally accomplished
|
|
* by relying on the module system to only have one copy of the module
|
|
* loaded, and then by giving the lock_torture_stats kthread full control
|
|
* (or the init/cleanup functions when lock_torture_stats thread is not
|
|
* running).
|
|
*/
|
|
static void lock_torture_stats_print(void)
|
|
{
|
|
int size = cxt.nrealwriters_stress * 200 + 8192;
|
|
char *buf;
|
|
|
|
if (cxt.cur_ops->readlock)
|
|
size += cxt.nrealreaders_stress * 200 + 8192;
|
|
|
|
buf = kmalloc(size, GFP_KERNEL);
|
|
if (!buf) {
|
|
pr_err("lock_torture_stats_print: Out of memory, need: %d",
|
|
size);
|
|
return;
|
|
}
|
|
|
|
__torture_print_stats(buf, cxt.lwsa, true);
|
|
pr_alert("%s", buf);
|
|
kfree(buf);
|
|
|
|
if (cxt.cur_ops->readlock) {
|
|
buf = kmalloc(size, GFP_KERNEL);
|
|
if (!buf) {
|
|
pr_err("lock_torture_stats_print: Out of memory, need: %d",
|
|
size);
|
|
return;
|
|
}
|
|
|
|
__torture_print_stats(buf, cxt.lrsa, false);
|
|
pr_alert("%s", buf);
|
|
kfree(buf);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Periodically prints torture statistics, if periodic statistics printing
|
|
* was specified via the stat_interval module parameter.
|
|
*
|
|
* No need to worry about fullstop here, since this one doesn't reference
|
|
* volatile state or register callbacks.
|
|
*/
|
|
static int lock_torture_stats(void *arg)
|
|
{
|
|
VERBOSE_TOROUT_STRING("lock_torture_stats task started");
|
|
do {
|
|
schedule_timeout_interruptible(stat_interval * HZ);
|
|
lock_torture_stats_print();
|
|
torture_shutdown_absorb("lock_torture_stats");
|
|
} while (!torture_must_stop());
|
|
torture_kthread_stopping("lock_torture_stats");
|
|
return 0;
|
|
}
|
|
|
|
static inline void
|
|
lock_torture_print_module_parms(struct lock_torture_ops *cur_ops,
|
|
const char *tag)
|
|
{
|
|
pr_alert("%s" TORTURE_FLAG
|
|
"--- %s%s: nwriters_stress=%d nreaders_stress=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n",
|
|
torture_type, tag, cxt.debug_lock ? " [debug]": "",
|
|
cxt.nrealwriters_stress, cxt.nrealreaders_stress, stat_interval,
|
|
verbose, shuffle_interval, stutter, shutdown_secs,
|
|
onoff_interval, onoff_holdoff);
|
|
}
|
|
|
|
static void lock_torture_cleanup(void)
|
|
{
|
|
int i;
|
|
|
|
if (torture_cleanup_begin())
|
|
return;
|
|
|
|
/*
|
|
* Indicates early cleanup, meaning that the test has not run,
|
|
* such as when passing bogus args when loading the module. As
|
|
* such, only perform the underlying torture-specific cleanups,
|
|
* and avoid anything related to locktorture.
|
|
*/
|
|
if (!cxt.lwsa && !cxt.lrsa)
|
|
goto end;
|
|
|
|
if (writer_tasks) {
|
|
for (i = 0; i < cxt.nrealwriters_stress; i++)
|
|
torture_stop_kthread(lock_torture_writer,
|
|
writer_tasks[i]);
|
|
kfree(writer_tasks);
|
|
writer_tasks = NULL;
|
|
}
|
|
|
|
if (reader_tasks) {
|
|
for (i = 0; i < cxt.nrealreaders_stress; i++)
|
|
torture_stop_kthread(lock_torture_reader,
|
|
reader_tasks[i]);
|
|
kfree(reader_tasks);
|
|
reader_tasks = NULL;
|
|
}
|
|
|
|
torture_stop_kthread(lock_torture_stats, stats_task);
|
|
lock_torture_stats_print(); /* -After- the stats thread is stopped! */
|
|
|
|
if (atomic_read(&cxt.n_lock_torture_errors))
|
|
lock_torture_print_module_parms(cxt.cur_ops,
|
|
"End of test: FAILURE");
|
|
else if (torture_onoff_failures())
|
|
lock_torture_print_module_parms(cxt.cur_ops,
|
|
"End of test: LOCK_HOTPLUG");
|
|
else
|
|
lock_torture_print_module_parms(cxt.cur_ops,
|
|
"End of test: SUCCESS");
|
|
|
|
kfree(cxt.lwsa);
|
|
cxt.lwsa = NULL;
|
|
kfree(cxt.lrsa);
|
|
cxt.lrsa = NULL;
|
|
|
|
end:
|
|
torture_cleanup_end();
|
|
}
|
|
|
|
static int __init lock_torture_init(void)
|
|
{
|
|
int i, j;
|
|
int firsterr = 0;
|
|
static struct lock_torture_ops *torture_ops[] = {
|
|
&lock_busted_ops,
|
|
&spin_lock_ops, &spin_lock_irq_ops,
|
|
&rw_lock_ops, &rw_lock_irq_ops,
|
|
&mutex_lock_ops,
|
|
&ww_mutex_lock_ops,
|
|
#ifdef CONFIG_RT_MUTEXES
|
|
&rtmutex_lock_ops,
|
|
#endif
|
|
&rwsem_lock_ops,
|
|
&percpu_rwsem_lock_ops,
|
|
};
|
|
|
|
if (!torture_init_begin(torture_type, verbose))
|
|
return -EBUSY;
|
|
|
|
/* Process args and tell the world that the torturer is on the job. */
|
|
for (i = 0; i < ARRAY_SIZE(torture_ops); i++) {
|
|
cxt.cur_ops = torture_ops[i];
|
|
if (strcmp(torture_type, cxt.cur_ops->name) == 0)
|
|
break;
|
|
}
|
|
if (i == ARRAY_SIZE(torture_ops)) {
|
|
pr_alert("lock-torture: invalid torture type: \"%s\"\n",
|
|
torture_type);
|
|
pr_alert("lock-torture types:");
|
|
for (i = 0; i < ARRAY_SIZE(torture_ops); i++)
|
|
pr_alert(" %s", torture_ops[i]->name);
|
|
pr_alert("\n");
|
|
firsterr = -EINVAL;
|
|
goto unwind;
|
|
}
|
|
|
|
if (nwriters_stress == 0 && nreaders_stress == 0) {
|
|
pr_alert("lock-torture: must run at least one locking thread\n");
|
|
firsterr = -EINVAL;
|
|
goto unwind;
|
|
}
|
|
|
|
if (cxt.cur_ops->init)
|
|
cxt.cur_ops->init();
|
|
|
|
if (nwriters_stress >= 0)
|
|
cxt.nrealwriters_stress = nwriters_stress;
|
|
else
|
|
cxt.nrealwriters_stress = 2 * num_online_cpus();
|
|
|
|
#ifdef CONFIG_DEBUG_MUTEXES
|
|
if (str_has_prefix(torture_type, "mutex"))
|
|
cxt.debug_lock = true;
|
|
#endif
|
|
#ifdef CONFIG_DEBUG_RT_MUTEXES
|
|
if (str_has_prefix(torture_type, "rtmutex"))
|
|
cxt.debug_lock = true;
|
|
#endif
|
|
#ifdef CONFIG_DEBUG_SPINLOCK
|
|
if ((str_has_prefix(torture_type, "spin")) ||
|
|
(str_has_prefix(torture_type, "rw_lock")))
|
|
cxt.debug_lock = true;
|
|
#endif
|
|
|
|
/* Initialize the statistics so that each run gets its own numbers. */
|
|
if (nwriters_stress) {
|
|
lock_is_write_held = 0;
|
|
cxt.lwsa = kmalloc_array(cxt.nrealwriters_stress,
|
|
sizeof(*cxt.lwsa),
|
|
GFP_KERNEL);
|
|
if (cxt.lwsa == NULL) {
|
|
VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory");
|
|
firsterr = -ENOMEM;
|
|
goto unwind;
|
|
}
|
|
|
|
for (i = 0; i < cxt.nrealwriters_stress; i++) {
|
|
cxt.lwsa[i].n_lock_fail = 0;
|
|
cxt.lwsa[i].n_lock_acquired = 0;
|
|
}
|
|
}
|
|
|
|
if (cxt.cur_ops->readlock) {
|
|
if (nreaders_stress >= 0)
|
|
cxt.nrealreaders_stress = nreaders_stress;
|
|
else {
|
|
/*
|
|
* By default distribute evenly the number of
|
|
* readers and writers. We still run the same number
|
|
* of threads as the writer-only locks default.
|
|
*/
|
|
if (nwriters_stress < 0) /* user doesn't care */
|
|
cxt.nrealwriters_stress = num_online_cpus();
|
|
cxt.nrealreaders_stress = cxt.nrealwriters_stress;
|
|
}
|
|
|
|
if (nreaders_stress) {
|
|
lock_is_read_held = 0;
|
|
cxt.lrsa = kmalloc_array(cxt.nrealreaders_stress,
|
|
sizeof(*cxt.lrsa),
|
|
GFP_KERNEL);
|
|
if (cxt.lrsa == NULL) {
|
|
VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory");
|
|
firsterr = -ENOMEM;
|
|
kfree(cxt.lwsa);
|
|
cxt.lwsa = NULL;
|
|
goto unwind;
|
|
}
|
|
|
|
for (i = 0; i < cxt.nrealreaders_stress; i++) {
|
|
cxt.lrsa[i].n_lock_fail = 0;
|
|
cxt.lrsa[i].n_lock_acquired = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
lock_torture_print_module_parms(cxt.cur_ops, "Start of test");
|
|
|
|
/* Prepare torture context. */
|
|
if (onoff_interval > 0) {
|
|
firsterr = torture_onoff_init(onoff_holdoff * HZ,
|
|
onoff_interval * HZ, NULL);
|
|
if (firsterr)
|
|
goto unwind;
|
|
}
|
|
if (shuffle_interval > 0) {
|
|
firsterr = torture_shuffle_init(shuffle_interval);
|
|
if (firsterr)
|
|
goto unwind;
|
|
}
|
|
if (shutdown_secs > 0) {
|
|
firsterr = torture_shutdown_init(shutdown_secs,
|
|
lock_torture_cleanup);
|
|
if (firsterr)
|
|
goto unwind;
|
|
}
|
|
if (stutter > 0) {
|
|
firsterr = torture_stutter_init(stutter, stutter);
|
|
if (firsterr)
|
|
goto unwind;
|
|
}
|
|
|
|
if (nwriters_stress) {
|
|
writer_tasks = kcalloc(cxt.nrealwriters_stress,
|
|
sizeof(writer_tasks[0]),
|
|
GFP_KERNEL);
|
|
if (writer_tasks == NULL) {
|
|
VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory");
|
|
firsterr = -ENOMEM;
|
|
goto unwind;
|
|
}
|
|
}
|
|
|
|
if (cxt.cur_ops->readlock) {
|
|
reader_tasks = kcalloc(cxt.nrealreaders_stress,
|
|
sizeof(reader_tasks[0]),
|
|
GFP_KERNEL);
|
|
if (reader_tasks == NULL) {
|
|
VERBOSE_TOROUT_ERRSTRING("reader_tasks: Out of memory");
|
|
kfree(writer_tasks);
|
|
writer_tasks = NULL;
|
|
firsterr = -ENOMEM;
|
|
goto unwind;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Create the kthreads and start torturing (oh, those poor little locks).
|
|
*
|
|
* TODO: Note that we interleave writers with readers, giving writers a
|
|
* slight advantage, by creating its kthread first. This can be modified
|
|
* for very specific needs, or even let the user choose the policy, if
|
|
* ever wanted.
|
|
*/
|
|
for (i = 0, j = 0; i < cxt.nrealwriters_stress ||
|
|
j < cxt.nrealreaders_stress; i++, j++) {
|
|
if (i >= cxt.nrealwriters_stress)
|
|
goto create_reader;
|
|
|
|
/* Create writer. */
|
|
firsterr = torture_create_kthread(lock_torture_writer, &cxt.lwsa[i],
|
|
writer_tasks[i]);
|
|
if (firsterr)
|
|
goto unwind;
|
|
|
|
create_reader:
|
|
if (cxt.cur_ops->readlock == NULL || (j >= cxt.nrealreaders_stress))
|
|
continue;
|
|
/* Create reader. */
|
|
firsterr = torture_create_kthread(lock_torture_reader, &cxt.lrsa[j],
|
|
reader_tasks[j]);
|
|
if (firsterr)
|
|
goto unwind;
|
|
}
|
|
if (stat_interval > 0) {
|
|
firsterr = torture_create_kthread(lock_torture_stats, NULL,
|
|
stats_task);
|
|
if (firsterr)
|
|
goto unwind;
|
|
}
|
|
torture_init_end();
|
|
return 0;
|
|
|
|
unwind:
|
|
torture_init_end();
|
|
lock_torture_cleanup();
|
|
return firsterr;
|
|
}
|
|
|
|
module_init(lock_torture_init);
|
|
module_exit(lock_torture_cleanup);
|