/*
- * Read-Copy Update /proc-based torture test facility
+ * Read-Copy Update module-based torture test facility
*
* 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
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
- * Copyright (C) IBM Corporation, 2005
+ * Copyright (C) IBM Corporation, 2005, 2006
*
* Authors: Paul E. McKenney <paulmck@us.ibm.com>
+ * Josh Triplett <josh@freedesktop.org>
*
* See also: Documentation/RCU/torture.txt
*/
#include <linux/sched.h>
#include <asm/atomic.h>
#include <linux/bitops.h>
-#include <linux/module.h>
#include <linux/completion.h>
#include <linux/moduleparam.h>
#include <linux/percpu.h>
#include <linux/notifier.h>
-#include <linux/rcuref.h>
+#include <linux/reboot.h>
+#include <linux/freezer.h>
#include <linux/cpu.h>
-#include <linux/random.h>
#include <linux/delay.h>
-#include <linux/byteorder/swabb.h>
#include <linux/stat.h>
+#include <linux/srcu.h>
+#include <linux/slab.h>
+#include <asm/byteorder.h>
MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and "
+ "Josh Triplett <josh@freedesktop.org>");
-static int nreaders = -1; /* # reader threads, defaults to 4*ncpus */
-static int stat_interval = 0; /* Interval between stats, in seconds. */
+static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */
+static int nfakewriters = 4; /* # fake writer threads */
+static int stat_interval; /* Interval between stats, in seconds. */
/* Defaults to "only at end of test". */
-static int verbose = 0; /* Print more debug info. */
+static int verbose; /* Print more debug info. */
+static int test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */
+static int shuffle_interval = 3; /* Interval between shuffles (in sec)*/
+static int stutter = 5; /* Start/stop testing interval (in sec) */
+static int irqreader = 1; /* RCU readers from irq (timers). */
+static char *torture_type = "rcu"; /* What RCU implementation to torture. */
-MODULE_PARM(nreaders, "i");
+module_param(nreaders, int, 0444);
MODULE_PARM_DESC(nreaders, "Number of RCU reader threads");
-MODULE_PARM(stat_interval, "i");
+module_param(nfakewriters, int, 0444);
+MODULE_PARM_DESC(nfakewriters, "Number of RCU fake writer threads");
+module_param(stat_interval, int, 0444);
MODULE_PARM_DESC(stat_interval, "Number of seconds between stats printk()s");
-MODULE_PARM(verbose, "i");
+module_param(verbose, bool, 0444);
MODULE_PARM_DESC(verbose, "Enable verbose debugging printk()s");
-#define TORTURE_FLAG "rcutorture: "
+module_param(test_no_idle_hz, bool, 0444);
+MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs");
+module_param(shuffle_interval, int, 0444);
+MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles");
+module_param(stutter, int, 0444);
+MODULE_PARM_DESC(stutter, "Number of seconds to run/halt test");
+module_param(irqreader, int, 0444);
+MODULE_PARM_DESC(irqreader, "Allow RCU readers from irq handlers");
+module_param(torture_type, charp, 0444);
+MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, srcu)");
+
+#define TORTURE_FLAG "-torture:"
#define PRINTK_STRING(s) \
- do { printk(KERN_ALERT TORTURE_FLAG s "\n"); } while (0)
+ do { printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0)
#define VERBOSE_PRINTK_STRING(s) \
- do { if (verbose) printk(KERN_ALERT TORTURE_FLAG s "\n"); } while (0)
+ do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0)
#define VERBOSE_PRINTK_ERRSTRING(s) \
- do { if (verbose) printk(KERN_ALERT TORTURE_FLAG "!!! " s "\n"); } while (0)
+ do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0)
static char printk_buf[4096];
static int nrealreaders;
static struct task_struct *writer_task;
+static struct task_struct **fakewriter_tasks;
static struct task_struct **reader_tasks;
static struct task_struct *stats_task;
+static struct task_struct *shuffler_task;
+static struct task_struct *stutter_task;
#define RCU_TORTURE_PIPE_LEN 10
int rtort_mbtest;
};
-static int fullstop = 0; /* stop generating callbacks at test end. */
static LIST_HEAD(rcu_torture_freelist);
-static struct rcu_torture *rcu_torture_current = NULL;
-static long rcu_torture_current_version = 0;
+static struct rcu_torture *rcu_torture_current;
+static long rcu_torture_current_version;
static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN];
static DEFINE_SPINLOCK(rcu_torture_lock);
static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) =
static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch) =
{ 0 };
static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1];
-atomic_t n_rcu_torture_alloc;
-atomic_t n_rcu_torture_alloc_fail;
-atomic_t n_rcu_torture_free;
-atomic_t n_rcu_torture_mberror;
-atomic_t n_rcu_torture_error;
+static atomic_t n_rcu_torture_alloc;
+static atomic_t n_rcu_torture_alloc_fail;
+static atomic_t n_rcu_torture_free;
+static atomic_t n_rcu_torture_mberror;
+static atomic_t n_rcu_torture_error;
+static long n_rcu_torture_timers;
+static struct list_head rcu_torture_removed;
+static cpumask_var_t shuffle_tmp_mask;
+
+static int stutter_pause_test;
+
+#if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE)
+#define RCUTORTURE_RUNNABLE_INIT 1
+#else
+#define RCUTORTURE_RUNNABLE_INIT 0
+#endif
+int rcutorture_runnable = RCUTORTURE_RUNNABLE_INIT;
+
+/* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */
+
+#define FULLSTOP_DONTSTOP 0 /* Normal operation. */
+#define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */
+#define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */
+static int fullstop = FULLSTOP_RMMOD;
+DEFINE_MUTEX(fullstop_mutex); /* Protect fullstop transitions and spawning */
+ /* of kthreads. */
+
+/*
+ * Detect and respond to a system shutdown.
+ */
+static int
+rcutorture_shutdown_notify(struct notifier_block *unused1,
+ unsigned long unused2, void *unused3)
+{
+ mutex_lock(&fullstop_mutex);
+ if (fullstop == FULLSTOP_DONTSTOP)
+ fullstop = FULLSTOP_SHUTDOWN;
+ else
+ printk(KERN_WARNING /* but going down anyway, so... */
+ "Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
+ mutex_unlock(&fullstop_mutex);
+ return NOTIFY_DONE;
+}
+
+/*
+ * Absorb kthreads into a kernel function that won't return, so that
+ * they won't ever access module text or data again.
+ */
+static void rcutorture_shutdown_absorb(char *title)
+{
+ if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
+ printk(KERN_NOTICE
+ "rcutorture thread %s parking due to system shutdown\n",
+ title);
+ schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
+ }
+}
/*
* Allocate an element from the rcu_tortures pool.
*/
-struct rcu_torture *
+static struct rcu_torture *
rcu_torture_alloc(void)
{
struct list_head *p;
- spin_lock(&rcu_torture_lock);
+ spin_lock_bh(&rcu_torture_lock);
if (list_empty(&rcu_torture_freelist)) {
atomic_inc(&n_rcu_torture_alloc_fail);
- spin_unlock(&rcu_torture_lock);
+ spin_unlock_bh(&rcu_torture_lock);
return NULL;
}
atomic_inc(&n_rcu_torture_alloc);
p = rcu_torture_freelist.next;
list_del_init(p);
- spin_unlock(&rcu_torture_lock);
+ spin_unlock_bh(&rcu_torture_lock);
return container_of(p, struct rcu_torture, rtort_free);
}
rcu_torture_free(struct rcu_torture *p)
{
atomic_inc(&n_rcu_torture_free);
- spin_lock(&rcu_torture_lock);
+ spin_lock_bh(&rcu_torture_lock);
list_add_tail(&p->rtort_free, &rcu_torture_freelist);
- spin_unlock(&rcu_torture_lock);
+ 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)cpu_clock(raw_smp_processor_id());
+ 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(char *title)
+{
+ while (stutter_pause_test || !rcutorture_runnable) {
+ if (rcutorture_runnable)
+ schedule_timeout_interruptible(1);
+ else
+ schedule_timeout_interruptible(round_jiffies_relative(HZ));
+ rcutorture_shutdown_absorb(title);
+ }
+}
+
+/*
+ * Operations vector for selecting different types of tests.
+ */
+
+struct rcu_torture_ops {
+ void (*init)(void);
+ void (*cleanup)(void);
+ int (*readlock)(void);
+ void (*read_delay)(struct rcu_random_state *rrsp);
+ void (*readunlock)(int idx);
+ int (*completed)(void);
+ void (*deferred_free)(struct rcu_torture *p);
+ void (*sync)(void);
+ void (*cb_barrier)(void);
+ int (*stats)(char *page);
+ int irq_capable;
+ char *name;
+};
+
+static struct rcu_torture_ops *cur_ops;
+
+/*
+ * Definitions for rcu torture testing.
+ */
+
+static int rcu_torture_read_lock(void) __acquires(RCU)
+{
+ rcu_read_lock();
+ return 0;
+}
+
+static void rcu_read_delay(struct rcu_random_state *rrsp)
+{
+ const unsigned long shortdelay_us = 200;
+ const unsigned long longdelay_ms = 50;
+
+ /* We want a short delay sometimes to make a reader delay the grace
+ * period, and we want a long delay occasionally to trigger
+ * force_quiescent_state. */
+
+ if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms)))
+ mdelay(longdelay_ms);
+ if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us)))
+ udelay(shortdelay_us);
+}
+
+static void rcu_torture_read_unlock(int idx) __releases(RCU)
+{
+ rcu_read_unlock();
+}
+
+static int rcu_torture_completed(void)
+{
+ return rcu_batches_completed();
}
static void
int i;
struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu);
- if (fullstop) {
+ if (fullstop != FULLSTOP_DONTSTOP) {
/* Test is ending, just drop callbacks on the floor. */
/* The next initialization will pick up the pieces. */
return;
rp->rtort_mbtest = 0;
rcu_torture_free(rp);
} else
- call_rcu(p, rcu_torture_cb);
+ cur_ops->deferred_free(rp);
}
-struct rcu_random_state {
- unsigned long rrs_state;
- unsigned long rrs_count;
+static int rcu_no_completed(void)
+{
+ return 0;
+}
+
+static void rcu_torture_deferred_free(struct rcu_torture *p)
+{
+ call_rcu(&p->rtort_rcu, rcu_torture_cb);
+}
+
+static struct rcu_torture_ops rcu_ops = {
+ .init = NULL,
+ .cleanup = NULL,
+ .readlock = rcu_torture_read_lock,
+ .read_delay = rcu_read_delay,
+ .readunlock = rcu_torture_read_unlock,
+ .completed = rcu_torture_completed,
+ .deferred_free = rcu_torture_deferred_free,
+ .sync = synchronize_rcu,
+ .cb_barrier = rcu_barrier,
+ .stats = NULL,
+ .irq_capable = 1,
+ .name = "rcu"
};
-#define RCU_RANDOM_MULT 39916801 /* prime */
-#define RCU_RANDOM_ADD 479001701 /* prime */
-#define RCU_RANDOM_REFRESH 10000
+static void rcu_sync_torture_deferred_free(struct rcu_torture *p)
+{
+ int i;
+ struct rcu_torture *rp;
+ struct rcu_torture *rp1;
-#define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 }
+ cur_ops->sync();
+ list_add(&p->rtort_free, &rcu_torture_removed);
+ list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) {
+ i = rp->rtort_pipe_count;
+ if (i > RCU_TORTURE_PIPE_LEN)
+ i = RCU_TORTURE_PIPE_LEN;
+ atomic_inc(&rcu_torture_wcount[i]);
+ if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) {
+ rp->rtort_mbtest = 0;
+ list_del(&rp->rtort_free);
+ rcu_torture_free(rp);
+ }
+ }
+}
+
+static void rcu_sync_torture_init(void)
+{
+ INIT_LIST_HEAD(&rcu_torture_removed);
+}
+
+static struct rcu_torture_ops rcu_sync_ops = {
+ .init = rcu_sync_torture_init,
+ .cleanup = NULL,
+ .readlock = rcu_torture_read_lock,
+ .read_delay = rcu_read_delay,
+ .readunlock = rcu_torture_read_unlock,
+ .completed = rcu_torture_completed,
+ .deferred_free = rcu_sync_torture_deferred_free,
+ .sync = synchronize_rcu,
+ .cb_barrier = NULL,
+ .stats = NULL,
+ .irq_capable = 1,
+ .name = "rcu_sync"
+};
+
+static struct rcu_torture_ops rcu_expedited_ops = {
+ .init = rcu_sync_torture_init,
+ .cleanup = NULL,
+ .readlock = rcu_torture_read_lock,
+ .read_delay = rcu_read_delay, /* just reuse rcu's version. */
+ .readunlock = rcu_torture_read_unlock,
+ .completed = rcu_no_completed,
+ .deferred_free = rcu_sync_torture_deferred_free,
+ .sync = synchronize_rcu_expedited,
+ .cb_barrier = NULL,
+ .stats = NULL,
+ .irq_capable = 1,
+ .name = "rcu_expedited"
+};
/*
- * Crude but fast random-number generator. Uses a linear congruential
- * generator, with occasional help from get_random_bytes().
+ * Definitions for rcu_bh torture testing.
*/
-static long
-rcu_random(struct rcu_random_state *rrsp)
+
+static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH)
{
- long refresh;
+ rcu_read_lock_bh();
+ return 0;
+}
- if (--rrsp->rrs_count < 0) {
- get_random_bytes(&refresh, sizeof(refresh));
- rrsp->rrs_state += refresh;
- rrsp->rrs_count = RCU_RANDOM_REFRESH;
+static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH)
+{
+ rcu_read_unlock_bh();
+}
+
+static int rcu_bh_torture_completed(void)
+{
+ return rcu_batches_completed_bh();
+}
+
+static void rcu_bh_torture_deferred_free(struct rcu_torture *p)
+{
+ call_rcu_bh(&p->rtort_rcu, rcu_torture_cb);
+}
+
+struct rcu_bh_torture_synchronize {
+ struct rcu_head head;
+ struct completion completion;
+};
+
+static void rcu_bh_torture_wakeme_after_cb(struct rcu_head *head)
+{
+ struct rcu_bh_torture_synchronize *rcu;
+
+ rcu = container_of(head, struct rcu_bh_torture_synchronize, head);
+ complete(&rcu->completion);
+}
+
+static void rcu_bh_torture_synchronize(void)
+{
+ struct rcu_bh_torture_synchronize rcu;
+
+ init_completion(&rcu.completion);
+ call_rcu_bh(&rcu.head, rcu_bh_torture_wakeme_after_cb);
+ wait_for_completion(&rcu.completion);
+}
+
+static struct rcu_torture_ops rcu_bh_ops = {
+ .init = NULL,
+ .cleanup = NULL,
+ .readlock = rcu_bh_torture_read_lock,
+ .read_delay = rcu_read_delay, /* just reuse rcu's version. */
+ .readunlock = rcu_bh_torture_read_unlock,
+ .completed = rcu_bh_torture_completed,
+ .deferred_free = rcu_bh_torture_deferred_free,
+ .sync = rcu_bh_torture_synchronize,
+ .cb_barrier = rcu_barrier_bh,
+ .stats = NULL,
+ .irq_capable = 1,
+ .name = "rcu_bh"
+};
+
+static struct rcu_torture_ops rcu_bh_sync_ops = {
+ .init = rcu_sync_torture_init,
+ .cleanup = NULL,
+ .readlock = rcu_bh_torture_read_lock,
+ .read_delay = rcu_read_delay, /* just reuse rcu's version. */
+ .readunlock = rcu_bh_torture_read_unlock,
+ .completed = rcu_bh_torture_completed,
+ .deferred_free = rcu_sync_torture_deferred_free,
+ .sync = rcu_bh_torture_synchronize,
+ .cb_barrier = NULL,
+ .stats = NULL,
+ .irq_capable = 1,
+ .name = "rcu_bh_sync"
+};
+
+/*
+ * Definitions for srcu torture testing.
+ */
+
+static struct srcu_struct srcu_ctl;
+
+static void srcu_torture_init(void)
+{
+ init_srcu_struct(&srcu_ctl);
+ rcu_sync_torture_init();
+}
+
+static void srcu_torture_cleanup(void)
+{
+ synchronize_srcu(&srcu_ctl);
+ cleanup_srcu_struct(&srcu_ctl);
+}
+
+static int srcu_torture_read_lock(void) __acquires(&srcu_ctl)
+{
+ return srcu_read_lock(&srcu_ctl);
+}
+
+static void srcu_read_delay(struct rcu_random_state *rrsp)
+{
+ long delay;
+ const long uspertick = 1000000 / HZ;
+ const long longdelay = 10;
+
+ /* We want there to be long-running readers, but not all the time. */
+
+ delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick);
+ if (!delay)
+ schedule_timeout_interruptible(longdelay);
+}
+
+static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl)
+{
+ srcu_read_unlock(&srcu_ctl, idx);
+}
+
+static int srcu_torture_completed(void)
+{
+ return srcu_batches_completed(&srcu_ctl);
+}
+
+static void srcu_torture_synchronize(void)
+{
+ synchronize_srcu(&srcu_ctl);
+}
+
+static int srcu_torture_stats(char *page)
+{
+ int cnt = 0;
+ int cpu;
+ int idx = srcu_ctl.completed & 0x1;
+
+ cnt += sprintf(&page[cnt], "%s%s per-CPU(idx=%d):",
+ torture_type, TORTURE_FLAG, idx);
+ for_each_possible_cpu(cpu) {
+ cnt += sprintf(&page[cnt], " %d(%d,%d)", cpu,
+ per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx],
+ per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]);
}
- rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD;
- return swahw32(rrsp->rrs_state);
+ cnt += sprintf(&page[cnt], "\n");
+ return cnt;
+}
+
+static struct rcu_torture_ops srcu_ops = {
+ .init = srcu_torture_init,
+ .cleanup = srcu_torture_cleanup,
+ .readlock = srcu_torture_read_lock,
+ .read_delay = srcu_read_delay,
+ .readunlock = srcu_torture_read_unlock,
+ .completed = srcu_torture_completed,
+ .deferred_free = rcu_sync_torture_deferred_free,
+ .sync = srcu_torture_synchronize,
+ .cb_barrier = NULL,
+ .stats = srcu_torture_stats,
+ .name = "srcu"
+};
+
+static void srcu_torture_synchronize_expedited(void)
+{
+ synchronize_srcu_expedited(&srcu_ctl);
+}
+
+static struct rcu_torture_ops srcu_expedited_ops = {
+ .init = srcu_torture_init,
+ .cleanup = srcu_torture_cleanup,
+ .readlock = srcu_torture_read_lock,
+ .read_delay = srcu_read_delay,
+ .readunlock = srcu_torture_read_unlock,
+ .completed = srcu_torture_completed,
+ .deferred_free = rcu_sync_torture_deferred_free,
+ .sync = srcu_torture_synchronize_expedited,
+ .cb_barrier = NULL,
+ .stats = srcu_torture_stats,
+ .name = "srcu_expedited"
+};
+
+/*
+ * Definitions for sched torture testing.
+ */
+
+static int sched_torture_read_lock(void)
+{
+ preempt_disable();
+ return 0;
+}
+
+static void sched_torture_read_unlock(int idx)
+{
+ preempt_enable();
+}
+
+static void rcu_sched_torture_deferred_free(struct rcu_torture *p)
+{
+ call_rcu_sched(&p->rtort_rcu, rcu_torture_cb);
}
+static void sched_torture_synchronize(void)
+{
+ synchronize_sched();
+}
+
+static struct rcu_torture_ops sched_ops = {
+ .init = rcu_sync_torture_init,
+ .cleanup = NULL,
+ .readlock = sched_torture_read_lock,
+ .read_delay = rcu_read_delay, /* just reuse rcu's version. */
+ .readunlock = sched_torture_read_unlock,
+ .completed = rcu_no_completed,
+ .deferred_free = rcu_sched_torture_deferred_free,
+ .sync = sched_torture_synchronize,
+ .cb_barrier = rcu_barrier_sched,
+ .stats = NULL,
+ .irq_capable = 1,
+ .name = "sched"
+};
+
+static struct rcu_torture_ops sched_sync_ops = {
+ .init = rcu_sync_torture_init,
+ .cleanup = NULL,
+ .readlock = sched_torture_read_lock,
+ .read_delay = rcu_read_delay, /* just reuse rcu's version. */
+ .readunlock = sched_torture_read_unlock,
+ .completed = rcu_no_completed,
+ .deferred_free = rcu_sync_torture_deferred_free,
+ .sync = sched_torture_synchronize,
+ .cb_barrier = NULL,
+ .stats = NULL,
+ .name = "sched_sync"
+};
+
+static struct rcu_torture_ops sched_expedited_ops = {
+ .init = rcu_sync_torture_init,
+ .cleanup = NULL,
+ .readlock = sched_torture_read_lock,
+ .read_delay = rcu_read_delay, /* just reuse rcu's version. */
+ .readunlock = sched_torture_read_unlock,
+ .completed = rcu_no_completed,
+ .deferred_free = rcu_sync_torture_deferred_free,
+ .sync = synchronize_sched_expedited,
+ .cb_barrier = NULL,
+ .stats = rcu_expedited_torture_stats,
+ .irq_capable = 1,
+ .name = "sched_expedited"
+};
+
/*
* RCU torture writer kthread. Repeatedly substitutes a new structure
* for that pointed to by rcu_torture_current, freeing the old structure
do {
schedule_timeout_uninterruptible(1);
- if (rcu_batches_completed() == oldbatch)
- continue;
- if ((rp = rcu_torture_alloc()) == NULL)
+ rp = rcu_torture_alloc();
+ if (rp == NULL)
continue;
rp->rtort_pipe_count = 0;
udelay(rcu_random(&rand) & 0x3ff);
old_rp = rcu_torture_current;
rp->rtort_mbtest = 1;
rcu_assign_pointer(rcu_torture_current, rp);
- smp_wmb();
- if (old_rp != NULL) {
+ smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */
+ if (old_rp) {
i = old_rp->rtort_pipe_count;
if (i > RCU_TORTURE_PIPE_LEN)
i = RCU_TORTURE_PIPE_LEN;
atomic_inc(&rcu_torture_wcount[i]);
old_rp->rtort_pipe_count++;
- call_rcu(&old_rp->rtort_rcu, rcu_torture_cb);
+ cur_ops->deferred_free(old_rp);
}
rcu_torture_current_version++;
- oldbatch = rcu_batches_completed();
- } while (!kthread_should_stop() && !fullstop);
+ oldbatch = cur_ops->completed();
+ rcu_stutter_wait("rcu_torture_writer");
+ } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping");
+ rcutorture_shutdown_absorb("rcu_torture_writer");
while (!kthread_should_stop())
schedule_timeout_uninterruptible(1);
return 0;
}
/*
+ * RCU torture fake writer kthread. Repeatedly calls sync, with a random
+ * delay between calls.
+ */
+static int
+rcu_torture_fakewriter(void *arg)
+{
+ DEFINE_RCU_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);
+ cur_ops->sync();
+ rcu_stutter_wait("rcu_torture_fakewriter");
+ } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
+
+ VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping");
+ rcutorture_shutdown_absorb("rcu_torture_fakewriter");
+ while (!kthread_should_stop())
+ schedule_timeout_uninterruptible(1);
+ return 0;
+}
+
+/*
+ * RCU torture reader from timer handler. Dereferences rcu_torture_current,
+ * incrementing the corresponding element of the pipeline array. The
+ * counter in the element should never be greater than 1, otherwise, the
+ * RCU implementation is broken.
+ */
+static void rcu_torture_timer(unsigned long unused)
+{
+ int idx;
+ int completed;
+ static DEFINE_RCU_RANDOM(rand);
+ static DEFINE_SPINLOCK(rand_lock);
+ struct rcu_torture *p;
+ int pipe_count;
+
+ idx = cur_ops->readlock();
+ completed = cur_ops->completed();
+ p = rcu_dereference(rcu_torture_current);
+ if (p == NULL) {
+ /* Leave because rcu_torture_writer is not yet underway */
+ cur_ops->readunlock(idx);
+ return;
+ }
+ if (p->rtort_mbtest == 0)
+ atomic_inc(&n_rcu_torture_mberror);
+ spin_lock(&rand_lock);
+ cur_ops->read_delay(&rand);
+ n_rcu_torture_timers++;
+ spin_unlock(&rand_lock);
+ preempt_disable();
+ pipe_count = p->rtort_pipe_count;
+ if (pipe_count > RCU_TORTURE_PIPE_LEN) {
+ /* Should not happen, but... */
+ pipe_count = RCU_TORTURE_PIPE_LEN;
+ }
+ __this_cpu_inc(per_cpu_var(rcu_torture_count)[pipe_count]);
+ completed = cur_ops->completed() - completed;
+ if (completed > RCU_TORTURE_PIPE_LEN) {
+ /* Should not happen, but... */
+ completed = RCU_TORTURE_PIPE_LEN;
+ }
+ __this_cpu_inc(per_cpu_var(rcu_torture_batch)[completed]);
+ preempt_enable();
+ cur_ops->readunlock(idx);
+}
+
+/*
* RCU torture reader kthread. Repeatedly dereferences rcu_torture_current,
* incrementing the corresponding element of the pipeline array. The
* counter in the element should never be greater than 1, otherwise, the
rcu_torture_reader(void *arg)
{
int completed;
+ int idx;
DEFINE_RCU_RANDOM(rand);
struct rcu_torture *p;
int pipe_count;
+ struct timer_list t;
VERBOSE_PRINTK_STRING("rcu_torture_reader task started");
set_user_nice(current, 19);
+ if (irqreader && cur_ops->irq_capable)
+ setup_timer_on_stack(&t, rcu_torture_timer, 0);
do {
- rcu_read_lock();
- completed = rcu_batches_completed();
+ if (irqreader && cur_ops->irq_capable) {
+ if (!timer_pending(&t))
+ mod_timer(&t, 1);
+ }
+ idx = cur_ops->readlock();
+ completed = cur_ops->completed();
p = rcu_dereference(rcu_torture_current);
if (p == NULL) {
/* Wait for rcu_torture_writer to get underway */
- rcu_read_unlock();
+ cur_ops->readunlock(idx);
schedule_timeout_interruptible(HZ);
continue;
}
if (p->rtort_mbtest == 0)
atomic_inc(&n_rcu_torture_mberror);
- udelay(rcu_random(&rand) & 0x7f);
+ cur_ops->read_delay(&rand);
preempt_disable();
pipe_count = p->rtort_pipe_count;
if (pipe_count > RCU_TORTURE_PIPE_LEN) {
/* Should not happen, but... */
pipe_count = RCU_TORTURE_PIPE_LEN;
}
- ++__get_cpu_var(rcu_torture_count)[pipe_count];
- completed = rcu_batches_completed() - completed;
+ __this_cpu_inc(per_cpu_var(rcu_torture_count)[pipe_count]);
+ completed = cur_ops->completed() - completed;
if (completed > RCU_TORTURE_PIPE_LEN) {
/* Should not happen, but... */
completed = RCU_TORTURE_PIPE_LEN;
}
- ++__get_cpu_var(rcu_torture_batch)[completed];
+ __this_cpu_inc(per_cpu_var(rcu_torture_batch)[completed]);
preempt_enable();
- rcu_read_unlock();
+ cur_ops->readunlock(idx);
schedule();
- } while (!kthread_should_stop() && !fullstop);
+ rcu_stutter_wait("rcu_torture_reader");
+ } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping");
+ rcutorture_shutdown_absorb("rcu_torture_reader");
+ if (irqreader && cur_ops->irq_capable)
+ del_timer_sync(&t);
while (!kthread_should_stop())
schedule_timeout_uninterruptible(1);
return 0;
long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 };
long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 };
- for_each_cpu(cpu) {
+ for_each_possible_cpu(cpu) {
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) {
pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i];
batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i];
if (pipesummary[i] != 0)
break;
}
- cnt += sprintf(&page[cnt], "rcutorture: ");
+ cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG);
cnt += sprintf(&page[cnt],
"rtc: %p ver: %ld tfle: %d rta: %d rtaf: %d rtf: %d "
- "rtmbe: %d",
+ "rtmbe: %d nt: %ld",
rcu_torture_current,
rcu_torture_current_version,
list_empty(&rcu_torture_freelist),
atomic_read(&n_rcu_torture_alloc),
atomic_read(&n_rcu_torture_alloc_fail),
atomic_read(&n_rcu_torture_free),
- atomic_read(&n_rcu_torture_mberror));
+ atomic_read(&n_rcu_torture_mberror),
+ n_rcu_torture_timers);
if (atomic_read(&n_rcu_torture_mberror) != 0)
cnt += sprintf(&page[cnt], " !!!");
- cnt += sprintf(&page[cnt], "\nrcutorture: ");
+ cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG);
if (i > 1) {
cnt += sprintf(&page[cnt], "!!! ");
atomic_inc(&n_rcu_torture_error);
+ WARN_ON_ONCE(1);
}
cnt += sprintf(&page[cnt], "Reader Pipe: ");
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
cnt += sprintf(&page[cnt], " %ld", pipesummary[i]);
- cnt += sprintf(&page[cnt], "\nrcutorture: ");
+ cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG);
cnt += sprintf(&page[cnt], "Reader Batch: ");
- for (i = 0; i < RCU_TORTURE_PIPE_LEN; i++)
+ for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
cnt += sprintf(&page[cnt], " %ld", batchsummary[i]);
- cnt += sprintf(&page[cnt], "\nrcutorture: ");
+ cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG);
cnt += sprintf(&page[cnt], "Free-Block Circulation: ");
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) {
cnt += sprintf(&page[cnt], " %d",
atomic_read(&rcu_torture_wcount[i]));
}
cnt += sprintf(&page[cnt], "\n");
+ if (cur_ops->stats)
+ cnt += cur_ops->stats(&page[cnt]);
return cnt;
}
do {
schedule_timeout_interruptible(stat_interval * HZ);
rcu_torture_stats_print();
+ rcutorture_shutdown_absorb("rcu_torture_stats");
} while (!kthread_should_stop());
VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping");
return 0;
}
+static int rcu_idle_cpu; /* Force all torture tasks off this CPU */
+
+/* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case
+ * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs.
+ */
+static void rcu_torture_shuffle_tasks(void)
+{
+ int i;
+
+ cpumask_setall(shuffle_tmp_mask);
+ get_online_cpus();
+
+ /* No point in shuffling if there is only one online CPU (ex: UP) */
+ if (num_online_cpus() == 1) {
+ put_online_cpus();
+ return;
+ }
+
+ if (rcu_idle_cpu != -1)
+ cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask);
+
+ set_cpus_allowed_ptr(current, shuffle_tmp_mask);
+
+ if (reader_tasks) {
+ for (i = 0; i < nrealreaders; i++)
+ if (reader_tasks[i])
+ set_cpus_allowed_ptr(reader_tasks[i],
+ shuffle_tmp_mask);
+ }
+
+ if (fakewriter_tasks) {
+ for (i = 0; i < nfakewriters; i++)
+ if (fakewriter_tasks[i])
+ set_cpus_allowed_ptr(fakewriter_tasks[i],
+ shuffle_tmp_mask);
+ }
+
+ if (writer_task)
+ set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask);
+
+ if (stats_task)
+ set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask);
+
+ if (rcu_idle_cpu == -1)
+ rcu_idle_cpu = num_online_cpus() - 1;
+ else
+ rcu_idle_cpu--;
+
+ put_online_cpus();
+}
+
+/* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
+ * system to become idle at a time and cut off its timer ticks. This is meant
+ * to test the support for such tickless idle CPU in RCU.
+ */
+static int
+rcu_torture_shuffle(void *arg)
+{
+ VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started");
+ do {
+ schedule_timeout_interruptible(shuffle_interval * HZ);
+ rcu_torture_shuffle_tasks();
+ rcutorture_shutdown_absorb("rcu_torture_shuffle");
+ } while (!kthread_should_stop());
+ VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping");
+ return 0;
+}
+
+/* Cause the rcutorture test to "stutter", starting and stopping all
+ * threads periodically.
+ */
+static int
+rcu_torture_stutter(void *arg)
+{
+ VERBOSE_PRINTK_STRING("rcu_torture_stutter task started");
+ do {
+ schedule_timeout_interruptible(stutter * HZ);
+ stutter_pause_test = 1;
+ if (!kthread_should_stop())
+ schedule_timeout_interruptible(stutter * HZ);
+ stutter_pause_test = 0;
+ rcutorture_shutdown_absorb("rcu_torture_stutter");
+ } while (!kthread_should_stop());
+ VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping");
+ return 0;
+}
+
+static inline void
+rcu_torture_print_module_parms(char *tag)
+{
+ printk(KERN_ALERT "%s" TORTURE_FLAG
+ "--- %s: nreaders=%d nfakewriters=%d "
+ "stat_interval=%d verbose=%d test_no_idle_hz=%d "
+ "shuffle_interval=%d stutter=%d irqreader=%d\n",
+ torture_type, tag, nrealreaders, nfakewriters,
+ stat_interval, verbose, test_no_idle_hz, shuffle_interval,
+ stutter, irqreader);
+}
+
+static struct notifier_block rcutorture_nb = {
+ .notifier_call = rcutorture_shutdown_notify,
+};
+
static void
rcu_torture_cleanup(void)
{
int i;
- fullstop = 1;
- if (writer_task != NULL) {
+ mutex_lock(&fullstop_mutex);
+ if (fullstop == FULLSTOP_SHUTDOWN) {
+ printk(KERN_WARNING /* but going down anyway, so... */
+ "Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
+ mutex_unlock(&fullstop_mutex);
+ schedule_timeout_uninterruptible(10);
+ if (cur_ops->cb_barrier != NULL)
+ cur_ops->cb_barrier();
+ return;
+ }
+ fullstop = FULLSTOP_RMMOD;
+ mutex_unlock(&fullstop_mutex);
+ unregister_reboot_notifier(&rcutorture_nb);
+ if (stutter_task) {
+ VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task");
+ kthread_stop(stutter_task);
+ }
+ stutter_task = NULL;
+ if (shuffler_task) {
+ VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task");
+ kthread_stop(shuffler_task);
+ free_cpumask_var(shuffle_tmp_mask);
+ }
+ shuffler_task = NULL;
+
+ if (writer_task) {
VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task");
kthread_stop(writer_task);
}
writer_task = NULL;
- if (reader_tasks != NULL) {
+ if (reader_tasks) {
for (i = 0; i < nrealreaders; i++) {
- if (reader_tasks[i] != NULL) {
+ if (reader_tasks[i]) {
VERBOSE_PRINTK_STRING(
"Stopping rcu_torture_reader task");
kthread_stop(reader_tasks[i]);
}
rcu_torture_current = NULL;
- if (stats_task != NULL) {
+ if (fakewriter_tasks) {
+ for (i = 0; i < nfakewriters; i++) {
+ if (fakewriter_tasks[i]) {
+ VERBOSE_PRINTK_STRING(
+ "Stopping rcu_torture_fakewriter task");
+ kthread_stop(fakewriter_tasks[i]);
+ }
+ fakewriter_tasks[i] = NULL;
+ }
+ kfree(fakewriter_tasks);
+ fakewriter_tasks = NULL;
+ }
+
+ if (stats_task) {
VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task");
kthread_stop(stats_task);
}
/* Wait for all RCU callbacks to fire. */
- for (i = 0; i < RCU_TORTURE_PIPE_LEN; i++)
- synchronize_rcu();
+ if (cur_ops->cb_barrier != NULL)
+ cur_ops->cb_barrier();
+
rcu_torture_stats_print(); /* -After- the stats thread is stopped! */
- printk(KERN_ALERT TORTURE_FLAG
- "--- End of test: %s\n",
- atomic_read(&n_rcu_torture_error) == 0 ? "SUCCESS" : "FAILURE");
+
+ if (cur_ops->cleanup)
+ cur_ops->cleanup();
+ if (atomic_read(&n_rcu_torture_error))
+ rcu_torture_print_module_parms("End of test: FAILURE");
+ else
+ rcu_torture_print_module_parms("End of test: SUCCESS");
}
-static int
+static int __init
rcu_torture_init(void)
{
int i;
int cpu;
int firsterr = 0;
+ static struct rcu_torture_ops *torture_ops[] =
+ { &rcu_ops, &rcu_sync_ops, &rcu_expedited_ops,
+ &rcu_bh_ops, &rcu_bh_sync_ops,
+ &srcu_ops, &srcu_expedited_ops,
+ &sched_ops, &sched_sync_ops, &sched_expedited_ops, };
+
+ mutex_lock(&fullstop_mutex);
/* Process args and tell the world that the torturer is on the job. */
+ for (i = 0; i < ARRAY_SIZE(torture_ops); i++) {
+ cur_ops = torture_ops[i];
+ if (strcmp(torture_type, cur_ops->name) == 0)
+ break;
+ }
+ if (i == ARRAY_SIZE(torture_ops)) {
+ printk(KERN_ALERT "rcu-torture: invalid torture type: \"%s\"\n",
+ torture_type);
+ printk(KERN_ALERT "rcu-torture types:");
+ for (i = 0; i < ARRAY_SIZE(torture_ops); i++)
+ printk(KERN_ALERT " %s", torture_ops[i]->name);
+ printk(KERN_ALERT "\n");
+ mutex_unlock(&fullstop_mutex);
+ return -EINVAL;
+ }
+ if (cur_ops->init)
+ cur_ops->init(); /* no "goto unwind" prior to this point!!! */
if (nreaders >= 0)
nrealreaders = nreaders;
else
nrealreaders = 2 * num_online_cpus();
- printk(KERN_ALERT TORTURE_FLAG
- "--- Start of test: nreaders=%d stat_interval=%d verbose=%d\n",
- nrealreaders, stat_interval, verbose);
- fullstop = 0;
+ rcu_torture_print_module_parms("Start of test");
+ fullstop = FULLSTOP_DONTSTOP;
/* Set up the freelist. */
INIT_LIST_HEAD(&rcu_torture_freelist);
- for (i = 0; i < sizeof(rcu_tortures) / sizeof(rcu_tortures[0]); i++) {
+ for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) {
rcu_tortures[i].rtort_mbtest = 0;
list_add_tail(&rcu_tortures[i].rtort_free,
&rcu_torture_freelist);
atomic_set(&n_rcu_torture_error, 0);
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
atomic_set(&rcu_torture_wcount[i], 0);
- for_each_cpu(cpu) {
+ for_each_possible_cpu(cpu) {
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) {
per_cpu(rcu_torture_count, cpu)[i] = 0;
per_cpu(rcu_torture_batch, cpu)[i] = 0;
writer_task = NULL;
goto unwind;
}
- reader_tasks = kmalloc(nrealreaders * sizeof(reader_tasks[0]),
+ fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]),
+ GFP_KERNEL);
+ if (fakewriter_tasks == NULL) {
+ VERBOSE_PRINTK_ERRSTRING("out of memory");
+ firsterr = -ENOMEM;
+ goto unwind;
+ }
+ for (i = 0; i < nfakewriters; i++) {
+ VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task");
+ fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL,
+ "rcu_torture_fakewriter");
+ if (IS_ERR(fakewriter_tasks[i])) {
+ firsterr = PTR_ERR(fakewriter_tasks[i]);
+ VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter");
+ fakewriter_tasks[i] = NULL;
+ goto unwind;
+ }
+ }
+ reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]),
GFP_KERNEL);
if (reader_tasks == NULL) {
VERBOSE_PRINTK_ERRSTRING("out of memory");
goto unwind;
}
}
+ if (test_no_idle_hz) {
+ rcu_idle_cpu = num_online_cpus() - 1;
+
+ if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
+ firsterr = -ENOMEM;
+ VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask");
+ goto unwind;
+ }
+
+ /* Create the shuffler thread */
+ shuffler_task = kthread_run(rcu_torture_shuffle, NULL,
+ "rcu_torture_shuffle");
+ if (IS_ERR(shuffler_task)) {
+ free_cpumask_var(shuffle_tmp_mask);
+ firsterr = PTR_ERR(shuffler_task);
+ VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler");
+ shuffler_task = NULL;
+ goto unwind;
+ }
+ }
+ if (stutter < 0)
+ stutter = 0;
+ if (stutter) {
+ /* Create the stutter thread */
+ stutter_task = kthread_run(rcu_torture_stutter, NULL,
+ "rcu_torture_stutter");
+ if (IS_ERR(stutter_task)) {
+ firsterr = PTR_ERR(stutter_task);
+ VERBOSE_PRINTK_ERRSTRING("Failed to create stutter");
+ stutter_task = NULL;
+ goto unwind;
+ }
+ }
+ register_reboot_notifier(&rcutorture_nb);
+ mutex_unlock(&fullstop_mutex);
return 0;
unwind:
+ mutex_unlock(&fullstop_mutex);
rcu_torture_cleanup();
return firsterr;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff