+++ /dev/null
-/*
- * 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
- * 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, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
- * 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/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/rcupdate.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/srcu.h>
-#include <linux/slab.h>
-#include <linux/trace_clock.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 fqs_duration;
-module_param(fqs_duration, int, 0444);
-MODULE_PARM_DESC(fqs_duration, "Duration of fqs bursts (us), 0 to disable");
-static int fqs_holdoff;
-module_param(fqs_holdoff, int, 0444);
-MODULE_PARM_DESC(fqs_holdoff, "Holdoff time within fqs bursts (us)");
-static int fqs_stutter = 3;
-module_param(fqs_stutter, int, 0444);
-MODULE_PARM_DESC(fqs_stutter, "Wait time between fqs bursts (s)");
-static bool gp_exp;
-module_param(gp_exp, bool, 0444);
-MODULE_PARM_DESC(gp_exp, "Use expedited GP wait primitives");
-static bool gp_normal;
-module_param(gp_normal, bool, 0444);
-MODULE_PARM_DESC(gp_normal, "Use normal (non-expedited) GP wait primitives");
-static int irqreader = 1;
-module_param(irqreader, int, 0444);
-MODULE_PARM_DESC(irqreader, "Allow RCU readers from irq handlers");
-static int n_barrier_cbs;
-module_param(n_barrier_cbs, int, 0444);
-MODULE_PARM_DESC(n_barrier_cbs, "# of callbacks/kthreads for barrier testing");
-static int nfakewriters = 4;
-module_param(nfakewriters, int, 0444);
-MODULE_PARM_DESC(nfakewriters, "Number of RCU fake writer threads");
-static int nreaders = -1;
-module_param(nreaders, int, 0444);
-MODULE_PARM_DESC(nreaders, "Number of RCU reader threads");
-static int object_debug;
-module_param(object_debug, int, 0444);
-MODULE_PARM_DESC(object_debug, "Enable debug-object double call_rcu() testing");
-static int onoff_holdoff;
-module_param(onoff_holdoff, int, 0444);
-MODULE_PARM_DESC(onoff_holdoff, "Time after boot before CPU hotplugs (s)");
-static int onoff_interval;
-module_param(onoff_interval, int, 0444);
-MODULE_PARM_DESC(onoff_interval, "Time between CPU hotplugs (s), 0=disable");
-static int shuffle_interval = 3;
-module_param(shuffle_interval, int, 0444);
-MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles");
-static int shutdown_secs;
-module_param(shutdown_secs, int, 0444);
-MODULE_PARM_DESC(shutdown_secs, "Shutdown time (s), <= zero to disable.");
-static int stall_cpu;
-module_param(stall_cpu, int, 0444);
-MODULE_PARM_DESC(stall_cpu, "Stall duration (s), zero to disable.");
-static int stall_cpu_holdoff = 10;
-module_param(stall_cpu_holdoff, int, 0444);
-MODULE_PARM_DESC(stall_cpu_holdoff, "Time to wait before starting stall (s).");
-static int stat_interval = 60;
-module_param(stat_interval, int, 0644);
-MODULE_PARM_DESC(stat_interval, "Number of seconds between stats printk()s");
-static int stutter = 5;
-module_param(stutter, int, 0444);
-MODULE_PARM_DESC(stutter, "Number of seconds to run/halt test");
-static int test_boost = 1;
-module_param(test_boost, int, 0444);
-MODULE_PARM_DESC(test_boost, "Test RCU prio boost: 0=no, 1=maybe, 2=yes.");
-static int test_boost_duration = 4;
-module_param(test_boost_duration, int, 0444);
-MODULE_PARM_DESC(test_boost_duration, "Duration of each boost test, seconds.");
-static int test_boost_interval = 7;
-module_param(test_boost_interval, int, 0444);
-MODULE_PARM_DESC(test_boost_interval, "Interval between boost tests, seconds.");
-static bool test_no_idle_hz = true;
-module_param(test_no_idle_hz, bool, 0444);
-MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs");
-static char *torture_type = "rcu";
-module_param(torture_type, charp, 0444);
-MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, ...)");
-static bool verbose;
-module_param(verbose, bool, 0444);
-MODULE_PARM_DESC(verbose, "Enable verbose debugging printk()s");
-
-#define TORTURE_FLAG "-torture:"
-#define PRINTK_STRING(s) \
- do { pr_alert("%s" TORTURE_FLAG s "\n", torture_type); } while (0)
-#define VERBOSE_PRINTK_STRING(s) \
- do { if (verbose) pr_alert("%s" TORTURE_FLAG s "\n", torture_type); } while (0)
-#define VERBOSE_PRINTK_ERRSTRING(s) \
- do { if (verbose) pr_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;
-static struct task_struct *fqs_task;
-static struct task_struct *boost_tasks[NR_CPUS];
-static struct task_struct *shutdown_task;
-#ifdef CONFIG_HOTPLUG_CPU
-static struct task_struct *onoff_task;
-#endif /* #ifdef CONFIG_HOTPLUG_CPU */
-static struct task_struct *stall_task;
-static struct task_struct **barrier_cbs_tasks;
-static struct task_struct *barrier_task;
-
-#define RCU_TORTURE_PIPE_LEN 10
-
-struct rcu_torture {
- struct rcu_head rtort_rcu;
- int rtort_pipe_count;
- struct list_head rtort_free;
- int rtort_mbtest;
-};
-
-static LIST_HEAD(rcu_torture_freelist);
-static struct rcu_torture __rcu *rcu_torture_current;
-static unsigned 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) =
- { 0 };
-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];
-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_barrier_error;
-static long n_rcu_torture_boost_ktrerror;
-static long n_rcu_torture_boost_rterror;
-static long n_rcu_torture_boost_failure;
-static long n_rcu_torture_boosts;
-static long n_rcu_torture_timers;
-static long n_offline_attempts;
-static long n_offline_successes;
-static unsigned long sum_offline;
-static int min_offline = -1;
-static int max_offline;
-static long n_online_attempts;
-static long n_online_successes;
-static unsigned long sum_online;
-static int min_online = -1;
-static int max_online;
-static long n_barrier_attempts;
-static long n_barrier_successes;
-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;
-module_param(rcutorture_runnable, int, 0444);
-MODULE_PARM_DESC(rcutorture_runnable, "Start rcutorture at boot");
-
-#if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU)
-#define rcu_can_boost() 1
-#else /* #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */
-#define rcu_can_boost() 0
-#endif /* #else #if defined(CONFIG_RCU_BOOST) && !defined(CONFIG_HOTPLUG_CPU) */
-
-#ifdef CONFIG_RCU_TRACE
-static u64 notrace rcu_trace_clock_local(void)
-{
- u64 ts = trace_clock_local();
- unsigned long __maybe_unused ts_rem = do_div(ts, NSEC_PER_USEC);
- return ts;
-}
-#else /* #ifdef CONFIG_RCU_TRACE */
-static u64 notrace rcu_trace_clock_local(void)
-{
- return 0ULL;
-}
-#endif /* #else #ifdef CONFIG_RCU_TRACE */
-
-static unsigned long shutdown_time; /* jiffies to system shutdown. */
-static unsigned long boost_starttime; /* jiffies of next boost test start. */
-DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */
- /* and boost task create/destroy. */
-static atomic_t barrier_cbs_count; /* Barrier callbacks registered. */
-static bool barrier_phase; /* Test phase. */
-static atomic_t barrier_cbs_invoked; /* Barrier callbacks invoked. */
-static wait_queue_head_t *barrier_cbs_wq; /* Coordinate barrier testing. */
-static DECLARE_WAIT_QUEUE_HEAD(barrier_wq);
-
-/* 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;
-/*
- * Protect fullstop transitions and spawning of kthreads.
- */
-static DEFINE_MUTEX(fullstop_mutex);
-
-/* Forward reference. */
-static void rcu_torture_cleanup(void);
-
-/*
- * 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
- pr_warn(/* 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(const char *title)
-{
- if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
- pr_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.
- */
-static struct rcu_torture *
-rcu_torture_alloc(void)
-{
- struct list_head *p;
-
- spin_lock_bh(&rcu_torture_lock);
- if (list_empty(&rcu_torture_freelist)) {
- atomic_inc(&n_rcu_torture_alloc_fail);
- 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_bh(&rcu_torture_lock);
- return container_of(p, struct rcu_torture, rtort_free);
-}
-
-/*
- * Free an element to the rcu_tortures pool.
- */
-static void
-rcu_torture_free(struct rcu_torture *p)
-{
- atomic_inc(&n_rcu_torture_free);
- spin_lock_bh(&rcu_torture_lock);
- list_add_tail(&p->rtort_free, &rcu_torture_freelist);
- 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)
-{
- 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);
- 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 (*exp_sync)(void);
- void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
- void (*cb_barrier)(void);
- void (*fqs)(void);
- int (*stats)(char *page);
- int irq_capable;
- int can_boost;
- const 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);
-#ifdef CONFIG_PREEMPT
- if (!preempt_count() && !(rcu_random(rrsp) % (nrealreaders * 20000)))
- preempt_schedule(); /* No QS if preempt_disable() in effect */
-#endif
-}
-
-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
-rcu_torture_cb(struct rcu_head *p)
-{
- int i;
- struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu);
-
- if (fullstop != FULLSTOP_DONTSTOP) {
- /* Test is ending, just drop callbacks on the floor. */
- /* The next initialization will pick up the pieces. */
- return;
- }
- 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;
- rcu_torture_free(rp);
- } else {
- cur_ops->deferred_free(rp);
- }
-}
-
-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 void rcu_sync_torture_init(void)
-{
- INIT_LIST_HEAD(&rcu_torture_removed);
-}
-
-static struct rcu_torture_ops rcu_ops = {
- .init = rcu_sync_torture_init,
- .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,
- .exp_sync = synchronize_rcu_expedited,
- .call = call_rcu,
- .cb_barrier = rcu_barrier,
- .fqs = rcu_force_quiescent_state,
- .stats = NULL,
- .irq_capable = 1,
- .can_boost = rcu_can_boost(),
- .name = "rcu"
-};
-
-/*
- * Definitions for rcu_bh torture testing.
- */
-
-static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH)
-{
- rcu_read_lock_bh();
- return 0;
-}
-
-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);
-}
-
-static struct rcu_torture_ops rcu_bh_ops = {
- .init = rcu_sync_torture_init,
- .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 = synchronize_rcu_bh,
- .exp_sync = synchronize_rcu_bh_expedited,
- .call = call_rcu_bh,
- .cb_barrier = rcu_barrier_bh,
- .fqs = rcu_bh_force_quiescent_state,
- .stats = NULL,
- .irq_capable = 1,
- .name = "rcu_bh"
-};
-
-/*
- * Definitions for srcu torture testing.
- */
-
-DEFINE_STATIC_SRCU(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);
- else
- rcu_read_delay(rrsp);
-}
-
-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_deferred_free(struct rcu_torture *rp)
-{
- call_srcu(&srcu_ctl, &rp->rtort_rcu, rcu_torture_cb);
-}
-
-static void srcu_torture_synchronize(void)
-{
- synchronize_srcu(&srcu_ctl);
-}
-
-static void srcu_torture_call(struct rcu_head *head,
- void (*func)(struct rcu_head *head))
-{
- call_srcu(&srcu_ctl, head, func);
-}
-
-static void srcu_torture_barrier(void)
-{
- srcu_barrier(&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(%lu,%lu)", cpu,
- per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx],
- per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]);
- }
- cnt += sprintf(&page[cnt], "\n");
- return cnt;
-}
-
-static void srcu_torture_synchronize_expedited(void)
-{
- synchronize_srcu_expedited(&srcu_ctl);
-}
-
-static struct rcu_torture_ops srcu_ops = {
- .init = rcu_sync_torture_init,
- .readlock = srcu_torture_read_lock,
- .read_delay = srcu_read_delay,
- .readunlock = srcu_torture_read_unlock,
- .completed = srcu_torture_completed,
- .deferred_free = srcu_torture_deferred_free,
- .sync = srcu_torture_synchronize,
- .exp_sync = srcu_torture_synchronize_expedited,
- .call = srcu_torture_call,
- .cb_barrier = srcu_torture_barrier,
- .stats = srcu_torture_stats,
- .name = "srcu"
-};
-
-/*
- * 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 struct rcu_torture_ops sched_ops = {
- .init = rcu_sync_torture_init,
- .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 = synchronize_sched,
- .exp_sync = synchronize_sched_expedited,
- .call = call_rcu_sched,
- .cb_barrier = rcu_barrier_sched,
- .fqs = rcu_sched_force_quiescent_state,
- .stats = NULL,
- .irq_capable = 1,
- .name = "sched"
-};
-
-/*
- * RCU torture priority-boost testing. Runs one real-time thread per
- * CPU for moderate bursts, repeatedly registering RCU callbacks and
- * spinning waiting for them to be invoked. If a given callback takes
- * too long to be invoked, we assume that priority inversion has occurred.
- */
-
-struct rcu_boost_inflight {
- struct rcu_head rcu;
- int inflight;
-};
-
-static void rcu_torture_boost_cb(struct rcu_head *head)
-{
- struct rcu_boost_inflight *rbip =
- container_of(head, struct rcu_boost_inflight, rcu);
-
- smp_mb(); /* Ensure RCU-core accesses precede clearing ->inflight */
- rbip->inflight = 0;
-}
-
-static int rcu_torture_boost(void *arg)
-{
- unsigned long call_rcu_time;
- unsigned long endtime;
- unsigned long oldstarttime;
- struct rcu_boost_inflight rbi = { .inflight = 0 };
- struct sched_param sp;
-
- VERBOSE_PRINTK_STRING("rcu_torture_boost started");
-
- /* Set real-time priority. */
- sp.sched_priority = 1;
- if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) {
- VERBOSE_PRINTK_STRING("rcu_torture_boost RT prio failed!");
- n_rcu_torture_boost_rterror++;
- }
-
- init_rcu_head_on_stack(&rbi.rcu);
- /* Each pass through the following loop does one boost-test cycle. */
- do {
- /* Wait for the next test interval. */
- oldstarttime = boost_starttime;
- while (ULONG_CMP_LT(jiffies, oldstarttime)) {
- schedule_timeout_interruptible(oldstarttime - jiffies);
- rcu_stutter_wait("rcu_torture_boost");
- if (kthread_should_stop() ||
- fullstop != FULLSTOP_DONTSTOP)
- goto checkwait;
- }
-
- /* Do one boost-test interval. */
- endtime = oldstarttime + test_boost_duration * HZ;
- call_rcu_time = jiffies;
- while (ULONG_CMP_LT(jiffies, endtime)) {
- /* If we don't have a callback in flight, post one. */
- if (!rbi.inflight) {
- smp_mb(); /* RCU core before ->inflight = 1. */
- rbi.inflight = 1;
- call_rcu(&rbi.rcu, rcu_torture_boost_cb);
- if (jiffies - call_rcu_time >
- test_boost_duration * HZ - HZ / 2) {
- VERBOSE_PRINTK_STRING("rcu_torture_boost boosting failed");
- n_rcu_torture_boost_failure++;
- }
- call_rcu_time = jiffies;
- }
- cond_resched();
- rcu_stutter_wait("rcu_torture_boost");
- if (kthread_should_stop() ||
- fullstop != FULLSTOP_DONTSTOP)
- goto checkwait;
- }
-
- /*
- * Set the start time of the next test interval.
- * Yes, this is vulnerable to long delays, but such
- * delays simply cause a false negative for the next
- * interval. Besides, we are running at RT priority,
- * so delays should be relatively rare.
- */
- while (oldstarttime == boost_starttime &&
- !kthread_should_stop()) {
- if (mutex_trylock(&boost_mutex)) {
- boost_starttime = jiffies +
- test_boost_interval * HZ;
- n_rcu_torture_boosts++;
- mutex_unlock(&boost_mutex);
- break;
- }
- schedule_timeout_uninterruptible(1);
- }
-
- /* Go do the stutter. */
-checkwait: rcu_stutter_wait("rcu_torture_boost");
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
-
- /* Clean up and exit. */
- VERBOSE_PRINTK_STRING("rcu_torture_boost task stopping");
- rcutorture_shutdown_absorb("rcu_torture_boost");
- while (!kthread_should_stop() || rbi.inflight)
- schedule_timeout_uninterruptible(1);
- smp_mb(); /* order accesses to ->inflight before stack-frame death. */
- destroy_rcu_head_on_stack(&rbi.rcu);
- return 0;
-}
-
-/*
- * RCU torture force-quiescent-state kthread. Repeatedly induces
- * bursts of calls to force_quiescent_state(), increasing the probability
- * of occurrence of some important types of race conditions.
- */
-static int
-rcu_torture_fqs(void *arg)
-{
- unsigned long fqs_resume_time;
- int fqs_burst_remaining;
-
- VERBOSE_PRINTK_STRING("rcu_torture_fqs task started");
- do {
- fqs_resume_time = jiffies + fqs_stutter * HZ;
- while (ULONG_CMP_LT(jiffies, fqs_resume_time) &&
- !kthread_should_stop()) {
- schedule_timeout_interruptible(1);
- }
- fqs_burst_remaining = fqs_duration;
- while (fqs_burst_remaining > 0 &&
- !kthread_should_stop()) {
- cur_ops->fqs();
- udelay(fqs_holdoff);
- fqs_burst_remaining -= fqs_holdoff;
- }
- rcu_stutter_wait("rcu_torture_fqs");
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
- VERBOSE_PRINTK_STRING("rcu_torture_fqs task stopping");
- rcutorture_shutdown_absorb("rcu_torture_fqs");
- while (!kthread_should_stop())
- schedule_timeout_uninterruptible(1);
- return 0;
-}
-
-/*
- * RCU torture writer kthread. Repeatedly substitutes a new structure
- * for that pointed to by rcu_torture_current, freeing the old structure
- * after a series of grace periods (the "pipeline").
- */
-static int
-rcu_torture_writer(void *arg)
-{
- bool exp;
- int i;
- struct rcu_torture *rp;
- struct rcu_torture *rp1;
- struct rcu_torture *old_rp;
- static DEFINE_RCU_RANDOM(rand);
-
- VERBOSE_PRINTK_STRING("rcu_torture_writer task started");
- set_user_nice(current, 19);
-
- do {
- schedule_timeout_uninterruptible(1);
- rp = rcu_torture_alloc();
- if (rp == NULL)
- continue;
- rp->rtort_pipe_count = 0;
- udelay(rcu_random(&rand) & 0x3ff);
- old_rp = rcu_dereference_check(rcu_torture_current,
- current == writer_task);
- rp->rtort_mbtest = 1;
- rcu_assign_pointer(rcu_torture_current, rp);
- 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++;
- if (gp_normal == gp_exp)
- exp = !!(rcu_random(&rand) & 0x80);
- else
- exp = gp_exp;
- if (!exp) {
- cur_ops->deferred_free(old_rp);
- } else {
- cur_ops->exp_sync();
- list_add(&old_rp->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);
- }
- }
- }
- }
- rcutorture_record_progress(++rcu_torture_current_version);
- 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);
- if (cur_ops->cb_barrier != NULL &&
- rcu_random(&rand) % (nfakewriters * 8) == 0) {
- cur_ops->cb_barrier();
- } else if (gp_normal == gp_exp) {
- if (rcu_random(&rand) & 0x80)
- cur_ops->sync();
- else
- cur_ops->exp_sync();
- } else if (gp_normal) {
- cur_ops->sync();
- } else {
- cur_ops->exp_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;
-}
-
-void rcutorture_trace_dump(void)
-{
- static atomic_t beenhere = ATOMIC_INIT(0);
-
- if (atomic_read(&beenhere))
- return;
- if (atomic_xchg(&beenhere, 1) != 0)
- return;
- ftrace_dump(DUMP_ALL);
-}
-
-/*
- * 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;
- int completed_end;
- static DEFINE_RCU_RANDOM(rand);
- static DEFINE_SPINLOCK(rand_lock);
- struct rcu_torture *p;
- int pipe_count;
- unsigned long long ts;
-
- idx = cur_ops->readlock();
- completed = cur_ops->completed();
- ts = rcu_trace_clock_local();
- p = rcu_dereference_check(rcu_torture_current,
- rcu_read_lock_bh_held() ||
- rcu_read_lock_sched_held() ||
- srcu_read_lock_held(&srcu_ctl));
- 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;
- }
- completed_end = cur_ops->completed();
- if (pipe_count > 1) {
- do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts,
- completed, completed_end);
- rcutorture_trace_dump();
- }
- __this_cpu_inc(rcu_torture_count[pipe_count]);
- completed = completed_end - completed;
- if (completed > RCU_TORTURE_PIPE_LEN) {
- /* Should not happen, but... */
- completed = RCU_TORTURE_PIPE_LEN;
- }
- __this_cpu_inc(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 implementation is broken.
- */
-static int
-rcu_torture_reader(void *arg)
-{
- int completed;
- int completed_end;
- int idx;
- DEFINE_RCU_RANDOM(rand);
- struct rcu_torture *p;
- int pipe_count;
- struct timer_list t;
- unsigned long long ts;
-
- 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 {
- if (irqreader && cur_ops->irq_capable) {
- if (!timer_pending(&t))
- mod_timer(&t, jiffies + 1);
- }
- idx = cur_ops->readlock();
- completed = cur_ops->completed();
- ts = rcu_trace_clock_local();
- p = rcu_dereference_check(rcu_torture_current,
- rcu_read_lock_bh_held() ||
- rcu_read_lock_sched_held() ||
- srcu_read_lock_held(&srcu_ctl));
- if (p == NULL) {
- /* Wait for rcu_torture_writer to get underway */
- cur_ops->readunlock(idx);
- schedule_timeout_interruptible(HZ);
- continue;
- }
- if (p->rtort_mbtest == 0)
- atomic_inc(&n_rcu_torture_mberror);
- 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;
- }
- completed_end = cur_ops->completed();
- if (pipe_count > 1) {
- do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu,
- ts, completed, completed_end);
- rcutorture_trace_dump();
- }
- __this_cpu_inc(rcu_torture_count[pipe_count]);
- completed = completed_end - completed;
- if (completed > RCU_TORTURE_PIPE_LEN) {
- /* Should not happen, but... */
- completed = RCU_TORTURE_PIPE_LEN;
- }
- __this_cpu_inc(rcu_torture_batch[completed]);
- preempt_enable();
- cur_ops->readunlock(idx);
- schedule();
- 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;
-}
-
-/*
- * Create an RCU-torture statistics message in the specified buffer.
- */
-static int
-rcu_torture_printk(char *page)
-{
- int cnt = 0;
- int cpu;
- int i;
- long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 };
- long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 };
-
- 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];
- }
- }
- for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) {
- if (pipesummary[i] != 0)
- break;
- }
- cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG);
- cnt += sprintf(&page[cnt],
- "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ",
- 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));
- cnt += sprintf(&page[cnt], "rtmbe: %d rtbke: %ld rtbre: %ld ",
- atomic_read(&n_rcu_torture_mberror),
- n_rcu_torture_boost_ktrerror,
- n_rcu_torture_boost_rterror);
- cnt += sprintf(&page[cnt], "rtbf: %ld rtb: %ld nt: %ld ",
- n_rcu_torture_boost_failure,
- n_rcu_torture_boosts,
- n_rcu_torture_timers);
- cnt += sprintf(&page[cnt],
- "onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
- n_online_successes, n_online_attempts,
- n_offline_successes, n_offline_attempts,
- min_online, max_online,
- min_offline, max_offline,
- sum_online, sum_offline, HZ);
- cnt += sprintf(&page[cnt], "barrier: %ld/%ld:%ld",
- n_barrier_successes,
- n_barrier_attempts,
- n_rcu_torture_barrier_error);
- cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG);
- if (atomic_read(&n_rcu_torture_mberror) != 0 ||
- n_rcu_torture_barrier_error != 0 ||
- n_rcu_torture_boost_ktrerror != 0 ||
- n_rcu_torture_boost_rterror != 0 ||
- n_rcu_torture_boost_failure != 0 ||
- 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], "\n%s%s ", torture_type, TORTURE_FLAG);
- cnt += sprintf(&page[cnt], "Reader Batch: ");
- for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
- cnt += sprintf(&page[cnt], " %ld", batchsummary[i]);
- 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;
-}
-
-/*
- * 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 rcu_torture_stats
- * kthread full control (or the init/cleanup functions when rcu_torture_stats
- * thread is not running).
- */
-static void
-rcu_torture_stats_print(void)
-{
- int cnt;
-
- cnt = rcu_torture_printk(printk_buf);
- pr_alert("%s", printk_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
-rcu_torture_stats(void *arg)
-{
- VERBOSE_PRINTK_STRING("rcu_torture_stats task started");
- 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 (stutter_task)
- set_cpus_allowed_ptr(stutter_task, shuffle_tmp_mask);
- if (fqs_task)
- set_cpus_allowed_ptr(fqs_task, shuffle_tmp_mask);
- if (shutdown_task)
- set_cpus_allowed_ptr(shutdown_task, shuffle_tmp_mask);
-#ifdef CONFIG_HOTPLUG_CPU
- if (onoff_task)
- set_cpus_allowed_ptr(onoff_task, shuffle_tmp_mask);
-#endif /* #ifdef CONFIG_HOTPLUG_CPU */
- if (stall_task)
- set_cpus_allowed_ptr(stall_task, shuffle_tmp_mask);
- if (barrier_cbs_tasks)
- for (i = 0; i < n_barrier_cbs; i++)
- if (barrier_cbs_tasks[i])
- set_cpus_allowed_ptr(barrier_cbs_tasks[i],
- shuffle_tmp_mask);
- if (barrier_task)
- set_cpus_allowed_ptr(barrier_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(struct rcu_torture_ops *cur_ops, const char *tag)
-{
- pr_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 "
- "fqs_duration=%d fqs_holdoff=%d fqs_stutter=%d "
- "test_boost=%d/%d test_boost_interval=%d "
- "test_boost_duration=%d shutdown_secs=%d "
- "stall_cpu=%d stall_cpu_holdoff=%d "
- "n_barrier_cbs=%d "
- "onoff_interval=%d onoff_holdoff=%d\n",
- torture_type, tag, nrealreaders, nfakewriters,
- stat_interval, verbose, test_no_idle_hz, shuffle_interval,
- stutter, irqreader, fqs_duration, fqs_holdoff, fqs_stutter,
- test_boost, cur_ops->can_boost,
- test_boost_interval, test_boost_duration, shutdown_secs,
- stall_cpu, stall_cpu_holdoff,
- n_barrier_cbs,
- onoff_interval, onoff_holdoff);
-}
-
-static struct notifier_block rcutorture_shutdown_nb = {
- .notifier_call = rcutorture_shutdown_notify,
-};
-
-static void rcutorture_booster_cleanup(int cpu)
-{
- struct task_struct *t;
-
- if (boost_tasks[cpu] == NULL)
- return;
- mutex_lock(&boost_mutex);
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_boost task");
- t = boost_tasks[cpu];
- boost_tasks[cpu] = NULL;
- mutex_unlock(&boost_mutex);
-
- /* This must be outside of the mutex, otherwise deadlock! */
- kthread_stop(t);
- boost_tasks[cpu] = NULL;
-}
-
-static int rcutorture_booster_init(int cpu)
-{
- int retval;
-
- if (boost_tasks[cpu] != NULL)
- return 0; /* Already created, nothing more to do. */
-
- /* Don't allow time recalculation while creating a new task. */
- mutex_lock(&boost_mutex);
- VERBOSE_PRINTK_STRING("Creating rcu_torture_boost task");
- boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL,
- cpu_to_node(cpu),
- "rcu_torture_boost");
- if (IS_ERR(boost_tasks[cpu])) {
- retval = PTR_ERR(boost_tasks[cpu]);
- VERBOSE_PRINTK_STRING("rcu_torture_boost task create failed");
- n_rcu_torture_boost_ktrerror++;
- boost_tasks[cpu] = NULL;
- mutex_unlock(&boost_mutex);
- return retval;
- }
- kthread_bind(boost_tasks[cpu], cpu);
- wake_up_process(boost_tasks[cpu]);
- mutex_unlock(&boost_mutex);
- return 0;
-}
-
-/*
- * Cause the rcutorture test to shutdown the system after the test has
- * run for the time specified by the shutdown_secs module parameter.
- */
-static int
-rcu_torture_shutdown(void *arg)
-{
- long delta;
- unsigned long jiffies_snap;
-
- VERBOSE_PRINTK_STRING("rcu_torture_shutdown task started");
- jiffies_snap = ACCESS_ONCE(jiffies);
- while (ULONG_CMP_LT(jiffies_snap, shutdown_time) &&
- !kthread_should_stop()) {
- delta = shutdown_time - jiffies_snap;
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_shutdown task: %lu jiffies remaining\n",
- torture_type, delta);
- schedule_timeout_interruptible(delta);
- jiffies_snap = ACCESS_ONCE(jiffies);
- }
- if (kthread_should_stop()) {
- VERBOSE_PRINTK_STRING("rcu_torture_shutdown task stopping");
- return 0;
- }
-
- /* OK, shut down the system. */
-
- VERBOSE_PRINTK_STRING("rcu_torture_shutdown task shutting down system");
- shutdown_task = NULL; /* Avoid self-kill deadlock. */
- rcu_torture_cleanup(); /* Get the success/failure message. */
- kernel_power_off(); /* Shut down the system. */
- return 0;
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-
-/*
- * Execute random CPU-hotplug operations at the interval specified
- * by the onoff_interval.
- */
-static int
-rcu_torture_onoff(void *arg)
-{
- int cpu;
- unsigned long delta;
- int maxcpu = -1;
- DEFINE_RCU_RANDOM(rand);
- int ret;
- unsigned long starttime;
-
- VERBOSE_PRINTK_STRING("rcu_torture_onoff task started");
- for_each_online_cpu(cpu)
- maxcpu = cpu;
- WARN_ON(maxcpu < 0);
- if (onoff_holdoff > 0) {
- VERBOSE_PRINTK_STRING("rcu_torture_onoff begin holdoff");
- schedule_timeout_interruptible(onoff_holdoff * HZ);
- VERBOSE_PRINTK_STRING("rcu_torture_onoff end holdoff");
- }
- while (!kthread_should_stop()) {
- cpu = (rcu_random(&rand) >> 4) % (maxcpu + 1);
- if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: offlining %d\n",
- torture_type, cpu);
- starttime = jiffies;
- n_offline_attempts++;
- ret = cpu_down(cpu);
- if (ret) {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: offline %d failed: errno %d\n",
- torture_type, cpu, ret);
- } else {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: offlined %d\n",
- torture_type, cpu);
- n_offline_successes++;
- delta = jiffies - starttime;
- sum_offline += delta;
- if (min_offline < 0) {
- min_offline = delta;
- max_offline = delta;
- }
- if (min_offline > delta)
- min_offline = delta;
- if (max_offline < delta)
- max_offline = delta;
- }
- } else if (cpu_is_hotpluggable(cpu)) {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: onlining %d\n",
- torture_type, cpu);
- starttime = jiffies;
- n_online_attempts++;
- ret = cpu_up(cpu);
- if (ret) {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: online %d failed: errno %d\n",
- torture_type, cpu, ret);
- } else {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: onlined %d\n",
- torture_type, cpu);
- n_online_successes++;
- delta = jiffies - starttime;
- sum_online += delta;
- if (min_online < 0) {
- min_online = delta;
- max_online = delta;
- }
- if (min_online > delta)
- min_online = delta;
- if (max_online < delta)
- max_online = delta;
- }
- }
- schedule_timeout_interruptible(onoff_interval * HZ);
- }
- VERBOSE_PRINTK_STRING("rcu_torture_onoff task stopping");
- return 0;
-}
-
-static int
-rcu_torture_onoff_init(void)
-{
- int ret;
-
- if (onoff_interval <= 0)
- return 0;
- onoff_task = kthread_run(rcu_torture_onoff, NULL, "rcu_torture_onoff");
- if (IS_ERR(onoff_task)) {
- ret = PTR_ERR(onoff_task);
- onoff_task = NULL;
- return ret;
- }
- return 0;
-}
-
-static void rcu_torture_onoff_cleanup(void)
-{
- if (onoff_task == NULL)
- return;
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_onoff task");
- kthread_stop(onoff_task);
- onoff_task = NULL;
-}
-
-#else /* #ifdef CONFIG_HOTPLUG_CPU */
-
-static int
-rcu_torture_onoff_init(void)
-{
- return 0;
-}
-
-static void rcu_torture_onoff_cleanup(void)
-{
-}
-
-#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
-
-/*
- * CPU-stall kthread. It waits as specified by stall_cpu_holdoff, then
- * induces a CPU stall for the time specified by stall_cpu.
- */
-static int rcu_torture_stall(void *args)
-{
- unsigned long stop_at;
-
- VERBOSE_PRINTK_STRING("rcu_torture_stall task started");
- if (stall_cpu_holdoff > 0) {
- VERBOSE_PRINTK_STRING("rcu_torture_stall begin holdoff");
- schedule_timeout_interruptible(stall_cpu_holdoff * HZ);
- VERBOSE_PRINTK_STRING("rcu_torture_stall end holdoff");
- }
- if (!kthread_should_stop()) {
- stop_at = get_seconds() + stall_cpu;
- /* RCU CPU stall is expected behavior in following code. */
- pr_alert("rcu_torture_stall start.\n");
- rcu_read_lock();
- preempt_disable();
- while (ULONG_CMP_LT(get_seconds(), stop_at))
- continue; /* Induce RCU CPU stall warning. */
- preempt_enable();
- rcu_read_unlock();
- pr_alert("rcu_torture_stall end.\n");
- }
- rcutorture_shutdown_absorb("rcu_torture_stall");
- while (!kthread_should_stop())
- schedule_timeout_interruptible(10 * HZ);
- return 0;
-}
-
-/* Spawn CPU-stall kthread, if stall_cpu specified. */
-static int __init rcu_torture_stall_init(void)
-{
- int ret;
-
- if (stall_cpu <= 0)
- return 0;
- stall_task = kthread_run(rcu_torture_stall, NULL, "rcu_torture_stall");
- if (IS_ERR(stall_task)) {
- ret = PTR_ERR(stall_task);
- stall_task = NULL;
- return ret;
- }
- return 0;
-}
-
-/* Clean up after the CPU-stall kthread, if one was spawned. */
-static void rcu_torture_stall_cleanup(void)
-{
- if (stall_task == NULL)
- return;
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_stall_task.");
- kthread_stop(stall_task);
- stall_task = NULL;
-}
-
-/* Callback function for RCU barrier testing. */
-void rcu_torture_barrier_cbf(struct rcu_head *rcu)
-{
- atomic_inc(&barrier_cbs_invoked);
-}
-
-/* kthread function to register callbacks used to test RCU barriers. */
-static int rcu_torture_barrier_cbs(void *arg)
-{
- long myid = (long)arg;
- bool lastphase = 0;
- struct rcu_head rcu;
-
- init_rcu_head_on_stack(&rcu);
- VERBOSE_PRINTK_STRING("rcu_torture_barrier_cbs task started");
- set_user_nice(current, 19);
- do {
- wait_event(barrier_cbs_wq[myid],
- barrier_phase != lastphase ||
- kthread_should_stop() ||
- fullstop != FULLSTOP_DONTSTOP);
- lastphase = barrier_phase;
- smp_mb(); /* ensure barrier_phase load before ->call(). */
- if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP)
- break;
- cur_ops->call(&rcu, rcu_torture_barrier_cbf);
- if (atomic_dec_and_test(&barrier_cbs_count))
- wake_up(&barrier_wq);
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
- VERBOSE_PRINTK_STRING("rcu_torture_barrier_cbs task stopping");
- rcutorture_shutdown_absorb("rcu_torture_barrier_cbs");
- while (!kthread_should_stop())
- schedule_timeout_interruptible(1);
- cur_ops->cb_barrier();
- destroy_rcu_head_on_stack(&rcu);
- return 0;
-}
-
-/* kthread function to drive and coordinate RCU barrier testing. */
-static int rcu_torture_barrier(void *arg)
-{
- int i;
-
- VERBOSE_PRINTK_STRING("rcu_torture_barrier task starting");
- do {
- atomic_set(&barrier_cbs_invoked, 0);
- atomic_set(&barrier_cbs_count, n_barrier_cbs);
- smp_mb(); /* Ensure barrier_phase after prior assignments. */
- barrier_phase = !barrier_phase;
- for (i = 0; i < n_barrier_cbs; i++)
- wake_up(&barrier_cbs_wq[i]);
- wait_event(barrier_wq,
- atomic_read(&barrier_cbs_count) == 0 ||
- kthread_should_stop() ||
- fullstop != FULLSTOP_DONTSTOP);
- if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP)
- break;
- n_barrier_attempts++;
- cur_ops->cb_barrier();
- if (atomic_read(&barrier_cbs_invoked) != n_barrier_cbs) {
- n_rcu_torture_barrier_error++;
- WARN_ON_ONCE(1);
- }
- n_barrier_successes++;
- schedule_timeout_interruptible(HZ / 10);
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
- VERBOSE_PRINTK_STRING("rcu_torture_barrier task stopping");
- rcutorture_shutdown_absorb("rcu_torture_barrier");
- while (!kthread_should_stop())
- schedule_timeout_interruptible(1);
- return 0;
-}
-
-/* Initialize RCU barrier testing. */
-static int rcu_torture_barrier_init(void)
-{
- int i;
- int ret;
-
- if (n_barrier_cbs == 0)
- return 0;
- if (cur_ops->call == NULL || cur_ops->cb_barrier == NULL) {
- pr_alert("%s" TORTURE_FLAG
- " Call or barrier ops missing for %s,\n",
- torture_type, cur_ops->name);
- pr_alert("%s" TORTURE_FLAG
- " RCU barrier testing omitted from run.\n",
- torture_type);
- return 0;
- }
- atomic_set(&barrier_cbs_count, 0);
- atomic_set(&barrier_cbs_invoked, 0);
- barrier_cbs_tasks =
- kzalloc(n_barrier_cbs * sizeof(barrier_cbs_tasks[0]),
- GFP_KERNEL);
- barrier_cbs_wq =
- kzalloc(n_barrier_cbs * sizeof(barrier_cbs_wq[0]),
- GFP_KERNEL);
- if (barrier_cbs_tasks == NULL || !barrier_cbs_wq)
- return -ENOMEM;
- for (i = 0; i < n_barrier_cbs; i++) {
- init_waitqueue_head(&barrier_cbs_wq[i]);
- barrier_cbs_tasks[i] = kthread_run(rcu_torture_barrier_cbs,
- (void *)(long)i,
- "rcu_torture_barrier_cbs");
- if (IS_ERR(barrier_cbs_tasks[i])) {
- ret = PTR_ERR(barrier_cbs_tasks[i]);
- VERBOSE_PRINTK_ERRSTRING("Failed to create rcu_torture_barrier_cbs");
- barrier_cbs_tasks[i] = NULL;
- return ret;
- }
- }
- barrier_task = kthread_run(rcu_torture_barrier, NULL,
- "rcu_torture_barrier");
- if (IS_ERR(barrier_task)) {
- ret = PTR_ERR(barrier_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create rcu_torture_barrier");
- barrier_task = NULL;
- }
- return 0;
-}
-
-/* Clean up after RCU barrier testing. */
-static void rcu_torture_barrier_cleanup(void)
-{
- int i;
-
- if (barrier_task != NULL) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_barrier task");
- kthread_stop(barrier_task);
- barrier_task = NULL;
- }
- if (barrier_cbs_tasks != NULL) {
- for (i = 0; i < n_barrier_cbs; i++) {
- if (barrier_cbs_tasks[i] != NULL) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_barrier_cbs task");
- kthread_stop(barrier_cbs_tasks[i]);
- barrier_cbs_tasks[i] = NULL;
- }
- }
- kfree(barrier_cbs_tasks);
- barrier_cbs_tasks = NULL;
- }
- if (barrier_cbs_wq != NULL) {
- kfree(barrier_cbs_wq);
- barrier_cbs_wq = NULL;
- }
-}
-
-static int rcutorture_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu)
-{
- long cpu = (long)hcpu;
-
- switch (action) {
- case CPU_ONLINE:
- case CPU_DOWN_FAILED:
- (void)rcutorture_booster_init(cpu);
- break;
- case CPU_DOWN_PREPARE:
- rcutorture_booster_cleanup(cpu);
- break;
- default:
- break;
- }
- return NOTIFY_OK;
-}
-
-static struct notifier_block rcutorture_cpu_nb = {
- .notifier_call = rcutorture_cpu_notify,
-};
-
-static void
-rcu_torture_cleanup(void)
-{
- int i;
-
- mutex_lock(&fullstop_mutex);
- rcutorture_record_test_transition();
- if (fullstop == FULLSTOP_SHUTDOWN) {
- pr_warn(/* 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_shutdown_nb);
- rcu_torture_barrier_cleanup();
- rcu_torture_stall_cleanup();
- 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) {
- for (i = 0; i < nrealreaders; i++) {
- if (reader_tasks[i]) {
- VERBOSE_PRINTK_STRING(
- "Stopping rcu_torture_reader task");
- kthread_stop(reader_tasks[i]);
- }
- reader_tasks[i] = NULL;
- }
- kfree(reader_tasks);
- reader_tasks = NULL;
- }
- rcu_torture_current = 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);
- }
- stats_task = NULL;
-
- if (fqs_task) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_fqs task");
- kthread_stop(fqs_task);
- }
- fqs_task = NULL;
- if ((test_boost == 1 && cur_ops->can_boost) ||
- test_boost == 2) {
- unregister_cpu_notifier(&rcutorture_cpu_nb);
- for_each_possible_cpu(i)
- rcutorture_booster_cleanup(i);
- }
- if (shutdown_task != NULL) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_shutdown task");
- kthread_stop(shutdown_task);
- }
- shutdown_task = NULL;
- rcu_torture_onoff_cleanup();
-
- /* Wait for all RCU callbacks to fire. */
-
- if (cur_ops->cb_barrier != NULL)
- cur_ops->cb_barrier();
-
- rcu_torture_stats_print(); /* -After- the stats thread is stopped! */
-
- if (atomic_read(&n_rcu_torture_error) || n_rcu_torture_barrier_error)
- rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE");
- else if (n_online_successes != n_online_attempts ||
- n_offline_successes != n_offline_attempts)
- rcu_torture_print_module_parms(cur_ops,
- "End of test: RCU_HOTPLUG");
- else
- rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS");
-}
-
-#ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD
-static void rcu_torture_leak_cb(struct rcu_head *rhp)
-{
-}
-
-static void rcu_torture_err_cb(struct rcu_head *rhp)
-{
- /*
- * This -might- happen due to race conditions, but is unlikely.
- * The scenario that leads to this happening is that the
- * first of the pair of duplicate callbacks is queued,
- * someone else starts a grace period that includes that
- * callback, then the second of the pair must wait for the
- * next grace period. Unlikely, but can happen. If it
- * does happen, the debug-objects subsystem won't have splatted.
- */
- pr_alert("rcutorture: duplicated callback was invoked.\n");
-}
-#endif /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */
-
-/*
- * Verify that double-free causes debug-objects to complain, but only
- * if CONFIG_DEBUG_OBJECTS_RCU_HEAD=y. Otherwise, say that the test
- * cannot be carried out.
- */
-static void rcu_test_debug_objects(void)
-{
-#ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD
- struct rcu_head rh1;
- struct rcu_head rh2;
-
- init_rcu_head_on_stack(&rh1);
- init_rcu_head_on_stack(&rh2);
- pr_alert("rcutorture: WARN: Duplicate call_rcu() test starting.\n");
-
- /* Try to queue the rh2 pair of callbacks for the same grace period. */
- preempt_disable(); /* Prevent preemption from interrupting test. */
- rcu_read_lock(); /* Make it impossible to finish a grace period. */
- call_rcu(&rh1, rcu_torture_leak_cb); /* Start grace period. */
- local_irq_disable(); /* Make it harder to start a new grace period. */
- call_rcu(&rh2, rcu_torture_leak_cb);
- call_rcu(&rh2, rcu_torture_err_cb); /* Duplicate callback. */
- local_irq_enable();
- rcu_read_unlock();
- preempt_enable();
-
- /* Wait for them all to get done so we can safely return. */
- rcu_barrier();
- pr_alert("rcutorture: WARN: Duplicate call_rcu() test complete.\n");
- destroy_rcu_head_on_stack(&rh1);
- destroy_rcu_head_on_stack(&rh2);
-#else /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */
- pr_alert("rcutorture: !CONFIG_DEBUG_OBJECTS_RCU_HEAD, not testing duplicate call_rcu()\n");
-#endif /* #else #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */
-}
-
-static int __init
-rcu_torture_init(void)
-{
- int i;
- int cpu;
- int firsterr = 0;
- int retval;
- static struct rcu_torture_ops *torture_ops[] = {
- &rcu_ops, &rcu_bh_ops, &srcu_ops, &sched_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)) {
- pr_alert("rcu-torture: invalid torture type: \"%s\"\n",
- torture_type);
- pr_alert("rcu-torture types:");
- for (i = 0; i < ARRAY_SIZE(torture_ops); i++)
- pr_alert(" %s", torture_ops[i]->name);
- pr_alert("\n");
- mutex_unlock(&fullstop_mutex);
- return -EINVAL;
- }
- if (cur_ops->fqs == NULL && fqs_duration != 0) {
- pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n");
- fqs_duration = 0;
- }
- 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();
- rcu_torture_print_module_parms(cur_ops, "Start of test");
- fullstop = FULLSTOP_DONTSTOP;
-
- /* Set up the freelist. */
-
- INIT_LIST_HEAD(&rcu_torture_freelist);
- 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);
- }
-
- /* Initialize the statistics so that each run gets its own numbers. */
-
- rcu_torture_current = NULL;
- rcu_torture_current_version = 0;
- atomic_set(&n_rcu_torture_alloc, 0);
- atomic_set(&n_rcu_torture_alloc_fail, 0);
- atomic_set(&n_rcu_torture_free, 0);
- atomic_set(&n_rcu_torture_mberror, 0);
- atomic_set(&n_rcu_torture_error, 0);
- n_rcu_torture_barrier_error = 0;
- n_rcu_torture_boost_ktrerror = 0;
- n_rcu_torture_boost_rterror = 0;
- n_rcu_torture_boost_failure = 0;
- n_rcu_torture_boosts = 0;
- for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++)
- atomic_set(&rcu_torture_wcount[i], 0);
- 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;
- }
- }
-
- /* Start up the kthreads. */
-
- VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task");
- writer_task = kthread_create(rcu_torture_writer, NULL,
- "rcu_torture_writer");
- if (IS_ERR(writer_task)) {
- firsterr = PTR_ERR(writer_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create writer");
- writer_task = NULL;
- goto unwind;
- }
- wake_up_process(writer_task);
- 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");
- firsterr = -ENOMEM;
- goto unwind;
- }
- for (i = 0; i < nrealreaders; i++) {
- VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task");
- reader_tasks[i] = kthread_run(rcu_torture_reader, NULL,
- "rcu_torture_reader");
- if (IS_ERR(reader_tasks[i])) {
- firsterr = PTR_ERR(reader_tasks[i]);
- VERBOSE_PRINTK_ERRSTRING("Failed to create reader");
- reader_tasks[i] = NULL;
- goto unwind;
- }
- }
- if (stat_interval > 0) {
- VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task");
- stats_task = kthread_run(rcu_torture_stats, NULL,
- "rcu_torture_stats");
- if (IS_ERR(stats_task)) {
- firsterr = PTR_ERR(stats_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create stats");
- stats_task = NULL;
- 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;
- }
- }
- if (fqs_duration < 0)
- fqs_duration = 0;
- if (fqs_duration) {
- /* Create the stutter thread */
- fqs_task = kthread_run(rcu_torture_fqs, NULL,
- "rcu_torture_fqs");
- if (IS_ERR(fqs_task)) {
- firsterr = PTR_ERR(fqs_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create fqs");
- fqs_task = NULL;
- goto unwind;
- }
- }
- if (test_boost_interval < 1)
- test_boost_interval = 1;
- if (test_boost_duration < 2)
- test_boost_duration = 2;
- if ((test_boost == 1 && cur_ops->can_boost) ||
- test_boost == 2) {
-
- boost_starttime = jiffies + test_boost_interval * HZ;
- register_cpu_notifier(&rcutorture_cpu_nb);
- for_each_possible_cpu(i) {
- if (cpu_is_offline(i))
- continue; /* Heuristic: CPU can go offline. */
- retval = rcutorture_booster_init(i);
- if (retval < 0) {
- firsterr = retval;
- goto unwind;
- }
- }
- }
- if (shutdown_secs > 0) {
- shutdown_time = jiffies + shutdown_secs * HZ;
- shutdown_task = kthread_create(rcu_torture_shutdown, NULL,
- "rcu_torture_shutdown");
- if (IS_ERR(shutdown_task)) {
- firsterr = PTR_ERR(shutdown_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create shutdown");
- shutdown_task = NULL;
- goto unwind;
- }
- wake_up_process(shutdown_task);
- }
- i = rcu_torture_onoff_init();
- if (i != 0) {
- firsterr = i;
- goto unwind;
- }
- register_reboot_notifier(&rcutorture_shutdown_nb);
- i = rcu_torture_stall_init();
- if (i != 0) {
- firsterr = i;
- goto unwind;
- }
- retval = rcu_torture_barrier_init();
- if (retval != 0) {
- firsterr = retval;
- goto unwind;
- }
- if (object_debug)
- rcu_test_debug_objects();
- rcutorture_record_test_transition();
- mutex_unlock(&fullstop_mutex);
- return 0;
-
-unwind:
- mutex_unlock(&fullstop_mutex);
- rcu_torture_cleanup();
- return firsterr;
-}
-
-module_init(rcu_torture_init);
-module_exit(rcu_torture_cleanup);
projects / cascardo / linux.git / blobdiff