torture: Abstract rcu_torture_random()
Because rcu_torture_random() will be used by the locking equivalent to
rcutorture, pull it out into its own module.
Suggested-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
diff --git a/include/linux/torture.h b/include/linux/torture.h
new file mode 100644
index 0000000..979e3e6
--- /dev/null
+++ b/include/linux/torture.h
@@ -0,0 +1,47 @@
+/*
+ * Common functions for in-kernel torture tests.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * Copyright IBM Corporation, 2014
+ *
+ * Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+ */
+
+#ifndef __LINUX_TORTURE_H
+#define __LINUX_TORTURE_H
+
+#include <linux/types.h>
+#include <linux/cache.h>
+#include <linux/spinlock.h>
+#include <linux/threads.h>
+#include <linux/cpumask.h>
+#include <linux/seqlock.h>
+#include <linux/lockdep.h>
+#include <linux/completion.h>
+#include <linux/debugobjects.h>
+#include <linux/bug.h>
+#include <linux/compiler.h>
+
+struct torture_random_state {
+ unsigned long trs_state;
+ long trs_count;
+};
+
+#define DEFINE_TORTURE_RANDOM(name) struct torture_random_state name = { 0, 0 }
+
+unsigned long torture_random(struct torture_random_state *trsp);
+
+#endif /* __LINUX_TORTURE_H */
diff --git a/kernel/Makefile b/kernel/Makefile
index bbaf7d5..e920dd6 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -93,6 +93,7 @@
obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
obj-$(CONFIG_JUMP_LABEL) += jump_label.o
obj-$(CONFIG_CONTEXT_TRACKING) += context_tracking.o
+obj-$(CONFIG_TORTURE_TEST) += torture.o
$(obj)/configs.o: $(obj)/config_data.h
diff --git a/kernel/rcu/torture.c b/kernel/rcu/torture.c
index 022c531..75d95af 100644
--- a/kernel/rcu/torture.c
+++ b/kernel/rcu/torture.c
@@ -48,6 +48,7 @@
#include <linux/slab.h>
#include <linux/trace_clock.h>
#include <asm/byteorder.h>
+#include <linux/torture.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@freedesktop.org>");
@@ -320,32 +321,6 @@
spin_unlock_bh(&rcu_torture_lock);
}
-struct rcu_random_state {
- unsigned long rrs_state;
- long rrs_count;
-};
-
-#define RCU_RANDOM_MULT 39916801 /* prime */
-#define RCU_RANDOM_ADD 479001701 /* prime */
-#define RCU_RANDOM_REFRESH 10000
-
-#define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 }
-
-/*
- * Crude but fast random-number generator. Uses a linear congruential
- * generator, with occasional help from cpu_clock().
- */
-static unsigned long
-rcu_random(struct rcu_random_state *rrsp)
-{
- if (--rrsp->rrs_count < 0) {
- rrsp->rrs_state += (unsigned long)local_clock();
- rrsp->rrs_count = RCU_RANDOM_REFRESH;
- }
- rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD;
- return swahw32(rrsp->rrs_state);
-}
-
static void
rcu_stutter_wait(const char *title)
{
@@ -365,7 +340,7 @@
struct rcu_torture_ops {
void (*init)(void);
int (*readlock)(void);
- void (*read_delay)(struct rcu_random_state *rrsp);
+ void (*read_delay)(struct torture_random_state *rrsp);
void (*readunlock)(int idx);
int (*completed)(void);
void (*deferred_free)(struct rcu_torture *p);
@@ -392,7 +367,7 @@
return 0;
}
-static void rcu_read_delay(struct rcu_random_state *rrsp)
+static void rcu_read_delay(struct torture_random_state *rrsp)
{
const unsigned long shortdelay_us = 200;
const unsigned long longdelay_ms = 50;
@@ -401,12 +376,13 @@
* period, and we want a long delay occasionally to trigger
* force_quiescent_state. */
- if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms)))
+ if (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms)))
mdelay(longdelay_ms);
- if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us)))
+ if (!(torture_random(rrsp) % (nrealreaders * 2 * shortdelay_us)))
udelay(shortdelay_us);
#ifdef CONFIG_PREEMPT
- if (!preempt_count() && !(rcu_random(rrsp) % (nrealreaders * 20000)))
+ if (!preempt_count() &&
+ !(torture_random(rrsp) % (nrealreaders * 20000)))
preempt_schedule(); /* No QS if preempt_disable() in effect */
#endif
}
@@ -530,7 +506,7 @@
return srcu_read_lock(&srcu_ctl);
}
-static void srcu_read_delay(struct rcu_random_state *rrsp)
+static void srcu_read_delay(struct torture_random_state *rrsp)
{
long delay;
const long uspertick = 1000000 / HZ;
@@ -538,7 +514,8 @@
/* We want there to be long-running readers, but not all the time. */
- delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick);
+ delay = torture_random(rrsp) %
+ (nrealreaders * 2 * longdelay * uspertick);
if (!delay)
schedule_timeout_interruptible(longdelay);
else
@@ -802,7 +779,7 @@
struct rcu_torture *rp;
struct rcu_torture *rp1;
struct rcu_torture *old_rp;
- static DEFINE_RCU_RANDOM(rand);
+ static DEFINE_TORTURE_RANDOM(rand);
VERBOSE_PRINTK_STRING("rcu_torture_writer task started");
set_user_nice(current, 19);
@@ -813,7 +790,7 @@
if (rp == NULL)
continue;
rp->rtort_pipe_count = 0;
- udelay(rcu_random(&rand) & 0x3ff);
+ udelay(torture_random(&rand) & 0x3ff);
old_rp = rcu_dereference_check(rcu_torture_current,
current == writer_task);
rp->rtort_mbtest = 1;
@@ -826,7 +803,7 @@
atomic_inc(&rcu_torture_wcount[i]);
old_rp->rtort_pipe_count++;
if (gp_normal == gp_exp)
- exp = !!(rcu_random(&rand) & 0x80);
+ exp = !!(torture_random(&rand) & 0x80);
else
exp = gp_exp;
if (!exp) {
@@ -868,19 +845,19 @@
static int
rcu_torture_fakewriter(void *arg)
{
- DEFINE_RCU_RANDOM(rand);
+ DEFINE_TORTURE_RANDOM(rand);
VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started");
set_user_nice(current, 19);
do {
- schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10);
- udelay(rcu_random(&rand) & 0x3ff);
+ schedule_timeout_uninterruptible(1 + torture_random(&rand)%10);
+ udelay(torture_random(&rand) & 0x3ff);
if (cur_ops->cb_barrier != NULL &&
- rcu_random(&rand) % (nfakewriters * 8) == 0) {
+ torture_random(&rand) % (nfakewriters * 8) == 0) {
cur_ops->cb_barrier();
} else if (gp_normal == gp_exp) {
- if (rcu_random(&rand) & 0x80)
+ if (torture_random(&rand) & 0x80)
cur_ops->sync();
else
cur_ops->exp_sync();
@@ -921,7 +898,7 @@
int idx;
int completed;
int completed_end;
- static DEFINE_RCU_RANDOM(rand);
+ static DEFINE_TORTURE_RANDOM(rand);
static DEFINE_SPINLOCK(rand_lock);
struct rcu_torture *p;
int pipe_count;
@@ -980,7 +957,7 @@
int completed;
int completed_end;
int idx;
- DEFINE_RCU_RANDOM(rand);
+ DEFINE_TORTURE_RANDOM(rand);
struct rcu_torture *p;
int pipe_count;
struct timer_list t;
@@ -1389,7 +1366,7 @@
int cpu;
unsigned long delta;
int maxcpu = -1;
- DEFINE_RCU_RANDOM(rand);
+ DEFINE_TORTURE_RANDOM(rand);
int ret;
unsigned long starttime;
@@ -1403,7 +1380,7 @@
VERBOSE_PRINTK_STRING("rcu_torture_onoff end holdoff");
}
while (!kthread_should_stop()) {
- cpu = (rcu_random(&rand) >> 4) % (maxcpu + 1);
+ cpu = (torture_random(&rand) >> 4) % (maxcpu + 1);
if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) {
if (verbose)
pr_alert("%s" TORTURE_FLAG
diff --git a/kernel/torture.c b/kernel/torture.c
new file mode 100644
index 0000000..c82c70f
--- /dev/null
+++ b/kernel/torture.c
@@ -0,0 +1,71 @@
+/*
+ * Common functions for in-kernel torture tests.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * Copyright (C) IBM Corporation, 2014
+ *
+ * Author: Paul E. McKenney <paulmck@us.ibm.com>
+ * Based on kernel/rcu/torture.c.
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/err.h>
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/completion.h>
+#include <linux/moduleparam.h>
+#include <linux/percpu.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/freezer.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/stat.h>
+#include <linux/slab.h>
+#include <linux/trace_clock.h>
+#include <asm/byteorder.h>
+#include <linux/torture.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>");
+
+#define TORTURE_RANDOM_MULT 39916801 /* prime */
+#define TORTURE_RANDOM_ADD 479001701 /* prime */
+#define TORTURE_RANDOM_REFRESH 10000
+
+/*
+ * Crude but fast random-number generator. Uses a linear congruential
+ * generator, with occasional help from cpu_clock().
+ */
+unsigned long
+torture_random(struct torture_random_state *trsp)
+{
+ if (--trsp->trs_count < 0) {
+ trsp->trs_state += (unsigned long)local_clock();
+ trsp->trs_count = TORTURE_RANDOM_REFRESH;
+ }
+ trsp->trs_state = trsp->trs_state * TORTURE_RANDOM_MULT +
+ TORTURE_RANDOM_ADD;
+ return swahw32(trsp->trs_state);
+}
+EXPORT_SYMBOL_GPL(torture_random);
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index db25707..dcfd2ce 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1132,9 +1132,19 @@
Say N if you are unsure.
+config TORTURE_TEST
+ tristate "in-kernel torture test infrastructure"
+ default n
+ help
+ This option provides a kernel module that provides infrastructure
+ for other torture-test kernel modules. This option is normally
+ selected by modules needing it. You should never need to manually
+ select this option.
+
config RCU_TORTURE_TEST
tristate "torture tests for RCU"
depends on DEBUG_KERNEL
+ select TORTURE_TEST
default n
help
This option provides a kernel module that runs torture tests
