| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Paul E. McKenney | 7981 | 89.26% | 137 | 71.73% |
| Josh Triplett | 357 | 3.99% | 10 | 5.24% |
| Joel A Fernandes | 285 | 3.19% | 4 | 2.09% |
| Srivatsa Vaddagiri | 67 | 0.75% | 1 | 0.52% |
| Steven Rostedt | 44 | 0.49% | 2 | 1.05% |
| Joe Perches | 40 | 0.45% | 2 | 1.05% |
| Sebastian Andrzej Siewior | 28 | 0.31% | 1 | 0.52% |
| Lai Jiangshan | 19 | 0.21% | 2 | 1.05% |
| Chen Gang S | 14 | 0.16% | 1 | 0.52% |
| Ingo Molnar | 14 | 0.16% | 5 | 2.62% |
| Rusty Russell | 12 | 0.13% | 2 | 1.05% |
| Christoph Lameter | 10 | 0.11% | 1 | 0.52% |
| Kees Cook | 9 | 0.10% | 2 | 1.05% |
| Thomas Gleixner | 8 | 0.09% | 1 | 0.52% |
| Eric Dumazet | 7 | 0.08% | 1 | 0.52% |
| Julia Lawall | 7 | 0.08% | 1 | 0.52% |
| Arnd Bergmann | 6 | 0.07% | 1 | 0.52% |
| Boqun Feng | 4 | 0.04% | 2 | 1.05% |
| Davidlohr Bueso A | 4 | 0.04% | 1 | 0.52% |
| Harvey Harrison | 4 | 0.04% | 1 | 0.52% |
| Rafael J. Wysocki | 3 | 0.03% | 1 | 0.52% |
| Mike Travis | 3 | 0.03% | 1 | 0.52% |
| SeongJae Park | 3 | 0.03% | 1 | 0.52% |
| Robert P. J. Day | 2 | 0.02% | 1 | 0.52% |
| Kamezawa Hiroyuki | 2 | 0.02% | 1 | 0.52% |
| Arun Sharma | 1 | 0.01% | 1 | 0.52% |
| Linus Torvalds | 1 | 0.01% | 1 | 0.52% |
| Ahmed S. Darwish | 1 | 0.01% | 1 | 0.52% |
| Rashika Kheria | 1 | 0.01% | 1 | 0.52% |
| Dongsheng Yang | 1 | 0.01% | 1 | 0.52% |
| Sasha Levin | 1 | 0.01% | 1 | 0.52% |
| Tejun Heo | 1 | 0.01% | 1 | 0.52% |
| Pranith Kumar | 1 | 0.01% | 1 | 0.52% |
| Total | 8941 | 191 |
/* * 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, you can access it online at * http://www.gnu.org/licenses/gpl-2.0.html. * * Copyright (C) IBM Corporation, 2005, 2006 * * Authors: Paul E. McKenney <paulmck@us.ibm.com> * Josh Triplett <josh@joshtriplett.org> * * See also: Documentation/RCU/torture.txt */ #define pr_fmt(fmt) fmt #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/signal.h> #include <uapi/linux/sched/types.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> #include <linux/torture.h> #include <linux/vmalloc.h> #include <linux/sched/debug.h> #include <linux/sched/sysctl.h> #include "rcu.h" MODULE_LICENSE("GPL"); MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@joshtriplett.org>"); /* Bits for ->extendables field, extendables param, and related definitions. */ #define RCUTORTURE_RDR_SHIFT 8 /* Put SRCU index in upper bits. */ #define RCUTORTURE_RDR_MASK ((1 << RCUTORTURE_RDR_SHIFT) - 1) #define RCUTORTURE_RDR_BH 0x1 /* Extend readers by disabling bh. */ #define RCUTORTURE_RDR_IRQ 0x2 /* ... disabling interrupts. */ #define RCUTORTURE_RDR_PREEMPT 0x4 /* ... disabling preemption. */ #define RCUTORTURE_RDR_RCU 0x8 /* ... entering another RCU reader. */ #define RCUTORTURE_RDR_NBITS 4 /* Number of bits defined above. */ #define RCUTORTURE_MAX_EXTEND (RCUTORTURE_RDR_BH | RCUTORTURE_RDR_IRQ | \ RCUTORTURE_RDR_PREEMPT) #define RCUTORTURE_RDR_MAX_LOOPS 0x7 /* Maximum reader extensions. */ /* Must be power of two minus one. */ torture_param(int, cbflood_inter_holdoff, HZ, "Holdoff between floods (jiffies)"); torture_param(int, cbflood_intra_holdoff, 1, "Holdoff between bursts (jiffies)"); torture_param(int, cbflood_n_burst, 3, "# bursts in flood, zero to disable"); torture_param(int, cbflood_n_per_burst, 20000, "# callbacks per burst in flood"); torture_param(int, extendables, RCUTORTURE_MAX_EXTEND, "Extend readers by disabling bh (1), irqs (2), or preempt (4)"); torture_param(int, fqs_duration, 0, "Duration of fqs bursts (us), 0 to disable"); torture_param(int, fqs_holdoff, 0, "Holdoff time within fqs bursts (us)"); torture_param(int, fqs_stutter, 3, "Wait time between fqs bursts (s)"); torture_param(bool, gp_cond, false, "Use conditional/async GP wait primitives"); torture_param(bool, gp_exp, false, "Use expedited GP wait primitives"); torture_param(bool, gp_normal, false, "Use normal (non-expedited) GP wait primitives"); torture_param(bool, gp_sync, false, "Use synchronous GP wait primitives"); torture_param(int, irqreader, 1, "Allow RCU readers from irq handlers"); torture_param(int, n_barrier_cbs, 0, "# of callbacks/kthreads for barrier testing"); torture_param(int, nfakewriters, 4, "Number of RCU fake writer threads"); torture_param(int, nreaders, -1, "Number of RCU reader threads"); torture_param(int, object_debug, 0, "Enable debug-object double call_rcu() testing"); torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)"); torture_param(int, onoff_interval, 0, "Time between CPU hotplugs (jiffies), 0=disable"); torture_param(int, shuffle_interval, 3, "Number of seconds between shuffles"); torture_param(int, shutdown_secs, 0, "Shutdown time (s), <= zero to disable."); torture_param(int, stall_cpu, 0, "Stall duration (s), zero to disable."); torture_param(int, stall_cpu_holdoff, 10, "Time to wait before starting stall (s)."); torture_param(int, stall_cpu_irqsoff, 0, "Disable interrupts while stalling."); torture_param(int, stat_interval, 60, "Number of seconds between stats printk()s"); torture_param(int, stutter, 5, "Number of seconds to run/halt test"); torture_param(int, test_boost, 1, "Test RCU prio boost: 0=no, 1=maybe, 2=yes."); torture_param(int, test_boost_duration, 4, "Duration of each boost test, seconds."); torture_param(int, test_boost_interval, 7, "Interval between boost tests, seconds."); torture_param(bool, test_no_idle_hz, true, "Test support for tickless idle CPUs"); torture_param(int, verbose, 1, "Enable verbose debugging printk()s"); 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 int nrealreaders; static int ncbflooders; 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 **cbflood_task; static struct task_struct *fqs_task; static struct task_struct *boost_tasks[NR_CPUS]; 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); static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch); 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 atomic_long_t n_rcu_torture_timers; static long n_barrier_attempts; static long n_barrier_successes; /* did rcu_barrier test succeed? */ static atomic_long_t n_cbfloods; static struct list_head rcu_torture_removed; static int rcu_torture_writer_state; #define RTWS_FIXED_DELAY 0 #define RTWS_DELAY 1 #define RTWS_REPLACE 2 #define RTWS_DEF_FREE 3 #define RTWS_EXP_SYNC 4 #define RTWS_COND_GET 5 #define RTWS_COND_SYNC 6 #define RTWS_SYNC 7 #define RTWS_STUTTER 8 #define RTWS_STOPPING 9 static const char * const rcu_torture_writer_state_names[] = { "RTWS_FIXED_DELAY", "RTWS_DELAY", "RTWS_REPLACE", "RTWS_DEF_FREE", "RTWS_EXP_SYNC", "RTWS_COND_GET", "RTWS_COND_SYNC", "RTWS_SYNC", "RTWS_STUTTER", "RTWS_STOPPING", }; static const char *rcu_torture_writer_state_getname(void) { unsigned int i = READ_ONCE(rcu_torture_writer_state); if (i >= ARRAY_SIZE(rcu_torture_writer_state_names)) return "???"; return rcu_torture_writer_state_names[i]; } #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(); (void)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 boost_starttime; /* jiffies of next boost test start. */ static 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); /* * 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); } /* * Operations vector for selecting different types of tests. */ struct rcu_torture_ops { int ttype; void (*init)(void); void (*cleanup)(void); int (*readlock)(void); void (*read_delay)(struct torture_random_state *rrsp); void (*readunlock)(int idx); unsigned long (*get_gp_seq)(void); unsigned long (*gp_diff)(unsigned long new, unsigned long old); void (*deferred_free)(struct rcu_torture *p); void (*sync)(void); void (*exp_sync)(void); unsigned long (*get_state)(void); void (*cond_sync)(unsigned long oldstate); call_rcu_func_t call; void (*cb_barrier)(void); void (*fqs)(void); void (*stats)(void); int irq_capable; int can_boost; int extendables; int ext_irq_conflict; 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 torture_random_state *rrsp) { unsigned long started; unsigned long completed; const unsigned long shortdelay_us = 200; const unsigned long longdelay_ms = 50; unsigned long long ts; /* 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 (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) { started = cur_ops->get_gp_seq(); ts = rcu_trace_clock_local(); mdelay(longdelay_ms); completed = cur_ops->get_gp_seq(); do_trace_rcu_torture_read(cur_ops->name, NULL, ts, started, completed); } if (!(torture_random(rrsp) % (nrealreaders * 2 * shortdelay_us))) udelay(shortdelay_us); if (!preempt_count() && !(torture_random(rrsp) % (nrealreaders * 500))) torture_preempt_schedule(); /* QS only if preemptible. */ } static void rcu_torture_read_unlock(int idx) __releases(RCU) { rcu_read_unlock(); } /* * Update callback in the pipe. This should be invoked after a grace period. */ static bool rcu_torture_pipe_update_one(struct rcu_torture *rp) { int i; 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; return true; } return false; } /* * Update all callbacks in the pipe. Suitable for synchronous grace-period * primitives. */ static void rcu_torture_pipe_update(struct rcu_torture *old_rp) { struct rcu_torture *rp; struct rcu_torture *rp1; if (old_rp) list_add(&old_rp->rtort_free, &rcu_torture_removed); list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) { if (rcu_torture_pipe_update_one(rp)) { list_del(&rp->rtort_free); rcu_torture_free(rp); } } } static void rcu_torture_cb(struct rcu_head *p) { struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); if (torture_must_stop_irq()) { /* Test is ending, just drop callbacks on the floor. */ /* The next initialization will pick up the pieces. */ return; } if (rcu_torture_pipe_update_one(rp)) rcu_torture_free(rp); else cur_ops->deferred_free(rp); } static unsigned long 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 = { .ttype = RCU_FLAVOR, .init = rcu_sync_torture_init, .readlock = rcu_torture_read_lock, .read_delay = rcu_read_delay, .readunlock = rcu_torture_read_unlock, .get_gp_seq = rcu_get_gp_seq, .gp_diff = rcu_seq_diff, .deferred_free = rcu_torture_deferred_free, .sync = synchronize_rcu, .exp_sync = synchronize_rcu_expedited, .get_state = get_state_synchronize_rcu, .cond_sync = cond_synchronize_rcu, .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 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 = { .ttype = RCU_BH_FLAVOR, .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, .get_gp_seq = rcu_bh_get_gp_seq, .gp_diff = rcu_seq_diff, .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, .extendables = (RCUTORTURE_RDR_BH | RCUTORTURE_RDR_IRQ), .ext_irq_conflict = RCUTORTURE_RDR_RCU, .name = "rcu_bh" }; /* * Don't even think about trying any of these in real life!!! * The names includes "busted", and they really means it! * The only purpose of these functions is to provide a buggy RCU * implementation to make sure that rcutorture correctly emits * buggy-RCU error messages. */ static void rcu_busted_torture_deferred_free(struct rcu_torture *p) { /* This is a deliberate bug for testing purposes only! */ rcu_torture_cb(&p->rtort_rcu); } static void synchronize_rcu_busted(void) { /* This is a deliberate bug for testing purposes only! */ } static void call_rcu_busted(struct rcu_head *head, rcu_callback_t func) { /* This is a deliberate bug for testing purposes only! */ func(head); } static struct rcu_torture_ops rcu_busted_ops = { .ttype = INVALID_RCU_FLAVOR, .init = rcu_sync_torture_init, .readlock = rcu_torture_read_lock, .read_delay = rcu_read_delay, /* just reuse rcu's version. */ .readunlock = rcu_torture_read_unlock, .get_gp_seq = rcu_no_completed, .deferred_free = rcu_busted_torture_deferred_free, .sync = synchronize_rcu_busted, .exp_sync = synchronize_rcu_busted, .call = call_rcu_busted, .cb_barrier = NULL, .fqs = NULL, .stats = NULL, .irq_capable = 1, .name = "busted" }; /* * Definitions for srcu torture testing. */ DEFINE_STATIC_SRCU(srcu_ctl); static struct srcu_struct srcu_ctld; static struct srcu_struct *srcu_ctlp = &srcu_ctl; static int srcu_torture_read_lock(void) __acquires(srcu_ctlp) { return srcu_read_lock(srcu_ctlp); } static void srcu_read_delay(struct torture_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 = torture_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick); if (!delay && in_task()) schedule_timeout_interruptible(longdelay); else rcu_read_delay(rrsp); } static void srcu_torture_read_unlock(int idx) __releases(srcu_ctlp) { srcu_read_unlock(srcu_ctlp, idx); } static unsigned long srcu_torture_completed(void) { return srcu_batches_completed(srcu_ctlp); } static void srcu_torture_deferred_free(struct rcu_torture *rp) { call_srcu(srcu_ctlp, &rp->rtort_rcu, rcu_torture_cb); } static void srcu_torture_synchronize(void) { synchronize_srcu(srcu_ctlp); } static void srcu_torture_call(struct rcu_head *head, rcu_callback_t func) { call_srcu(srcu_ctlp, head, func); } static void srcu_torture_barrier(void) { srcu_barrier(srcu_ctlp); } static void srcu_torture_stats(void) { srcu_torture_stats_print(srcu_ctlp, torture_type, TORTURE_FLAG); } static void srcu_torture_synchronize_expedited(void) { synchronize_srcu_expedited(srcu_ctlp); } static struct rcu_torture_ops srcu_ops = { .ttype = SRCU_FLAVOR, .init = rcu_sync_torture_init, .readlock = srcu_torture_read_lock, .read_delay = srcu_read_delay, .readunlock = srcu_torture_read_unlock, .get_gp_seq = 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, .irq_capable = 1, .name = "srcu" }; static void srcu_torture_init(void) { rcu_sync_torture_init(); WARN_ON(init_srcu_struct(&srcu_ctld)); srcu_ctlp = &srcu_ctld; } static void srcu_torture_cleanup(void) { static DEFINE_TORTURE_RANDOM(rand); if (torture_random(&rand) & 0x800) cleanup_srcu_struct(&srcu_ctld); else cleanup_srcu_struct_quiesced(&srcu_ctld); srcu_ctlp = &srcu_ctl; /* In case of a later rcutorture run. */ } /* As above, but dynamically allocated. */ static struct rcu_torture_ops srcud_ops = { .ttype = SRCU_FLAVOR, .init = srcu_torture_init, .cleanup = srcu_torture_cleanup, .readlock = srcu_torture_read_lock, .read_delay = srcu_read_delay, .readunlock = srcu_torture_read_unlock, .get_gp_seq = 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, .irq_capable = 1, .name = "srcud" }; /* As above, but broken due to inappropriate reader extension. */ static struct rcu_torture_ops busted_srcud_ops = { .ttype = SRCU_FLAVOR, .init = srcu_torture_init, .cleanup = srcu_torture_cleanup, .readlock = srcu_torture_read_lock, .read_delay = rcu_read_delay, .readunlock = srcu_torture_read_unlock, .get_gp_seq = 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, .irq_capable = 1, .extendables = RCUTORTURE_MAX_EXTEND, .name = "busted_srcud" }; /* * 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 = { .ttype = RCU_SCHED_FLAVOR, .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, .get_gp_seq = rcu_sched_get_gp_seq, .gp_diff = rcu_seq_diff, .deferred_free = rcu_sched_torture_deferred_free, .sync = synchronize_sched, .exp_sync = synchronize_sched_expedited, .get_state = get_state_synchronize_sched, .cond_sync = cond_synchronize_sched, .call = call_rcu_sched, .cb_barrier = rcu_barrier_sched, .fqs = rcu_sched_force_quiescent_state, .stats = NULL, .irq_capable = 1, .extendables = RCUTORTURE_MAX_EXTEND, .name = "sched" }; /* * Definitions for RCU-tasks torture testing. */ static int tasks_torture_read_lock(void) { return 0; } static void tasks_torture_read_unlock(int idx) { } static void rcu_tasks_torture_deferred_free(struct rcu_torture *p) { call_rcu_tasks(&p->rtort_rcu, rcu_torture_cb); } static struct rcu_torture_ops tasks_ops = { .ttype = RCU_TASKS_FLAVOR, .init = rcu_sync_torture_init, .readlock = tasks_torture_read_lock, .read_delay = rcu_read_delay, /* just reuse rcu's version. */ .readunlock = tasks_torture_read_unlock, .get_gp_seq = rcu_no_completed, .deferred_free = rcu_tasks_torture_deferred_free, .sync = synchronize_rcu_tasks, .exp_sync = synchronize_rcu_tasks, .call = call_rcu_tasks, .cb_barrier = rcu_barrier_tasks, .fqs = NULL, .stats = NULL, .irq_capable = 1, .name = "tasks" }; static unsigned long rcutorture_seq_diff(unsigned long new, unsigned long old) { if (!cur_ops->gp_diff) return new - old; return cur_ops->gp_diff(new, old); } static bool __maybe_unused torturing_tasks(void) { return cur_ops == &tasks_ops; } /* * 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); /* Ensure RCU-core accesses precede clearing ->inflight */ smp_store_release(&rbip->inflight, 0); } static int old_rt_runtime = -1; static void rcu_torture_disable_rt_throttle(void) { /* * Disable RT throttling so that rcutorture's boost threads don't get * throttled. Only possible if rcutorture is built-in otherwise the * user should manually do this by setting the sched_rt_period_us and * sched_rt_runtime sysctls. */ if (!IS_BUILTIN(CONFIG_RCU_TORTURE_TEST) || old_rt_runtime != -1) return; old_rt_runtime = sysctl_sched_rt_runtime; sysctl_sched_rt_runtime = -1; } static void rcu_torture_enable_rt_throttle(void) { if (!IS_BUILTIN(CONFIG_RCU_TORTURE_TEST) || old_rt_runtime == -1) return; sysctl_sched_rt_runtime = old_rt_runtime; old_rt_runtime = -1; } static bool rcu_torture_boost_failed(unsigned long start, unsigned long end) { if (end - start > test_boost_duration * HZ - HZ / 2) { VERBOSE_TOROUT_STRING("rcu_torture_boost boosting failed"); n_rcu_torture_boost_failure++; return true; /* failed */ } return false; /* passed */ } 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_TOROUT_STRING("rcu_torture_boost started"); /* Set real-time priority. */ sp.sched_priority = 1; if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) { VERBOSE_TOROUT_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 { /* Track if the test failed already in this test interval? */ bool failed = false; /* Increment n_rcu_torture_boosts once per boost-test */ while (!kthread_should_stop()) { if (mutex_trylock(&boost_mutex)) { n_rcu_torture_boosts++; mutex_unlock(&boost_mutex); break; } schedule_timeout_uninterruptible(1); } if (kthread_should_stop()) goto checkwait; /* Wait for the next test interval. */ oldstarttime = boost_starttime; while (ULONG_CMP_LT(jiffies, oldstarttime)) { schedule_timeout_interruptible(oldstarttime - jiffies); stutter_wait("rcu_torture_boost"); if (torture_must_stop()) 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 (!smp_load_acquire(&rbi.inflight)) { /* RCU core before ->inflight = 1. */ smp_store_release(&rbi.inflight, 1); call_rcu(&rbi.rcu, rcu_torture_boost_cb); /* Check if the boost test failed */ failed = failed || rcu_torture_boost_failed(call_rcu_time, jiffies); call_rcu_time = jiffies; } stutter_wait("rcu_torture_boost"); if (torture_must_stop()) goto checkwait; } /* * If boost never happened, then inflight will always be 1, in * this case the boost check would never happen in the above * loop so do another one here. */ if (!failed && smp_load_acquire(&rbi.inflight)) rcu_torture_boost_failed(call_rcu_time, jiffies); /* * 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; mutex_unlock(&boost_mutex); break; } schedule_timeout_uninterruptible(1); } /* Go do the stutter. */ checkwait: stutter_wait("rcu_torture_boost"); } while (!torture_must_stop()); /* Clean up and exit. */ while (!kthread_should_stop() || smp_load_acquire(&rbi.inflight)) { torture_shutdown_absorb("rcu_torture_boost"); schedule_timeout_uninterruptible(1); } destroy_rcu_head_on_stack(&rbi.rcu); torture_kthread_stopping("rcu_torture_boost"); return 0; } static void rcu_torture_cbflood_cb(struct rcu_head *rhp) { } /* * RCU torture callback-flood kthread. Repeatedly induces bursts of calls * to call_rcu() or analogous, increasing the probability of occurrence * of callback-overflow corner cases. */ static int rcu_torture_cbflood(void *arg) { int err = 1; int i; int j; struct rcu_head *rhp; if (cbflood_n_per_burst > 0 && cbflood_inter_holdoff > 0 && cbflood_intra_holdoff > 0 && cur_ops->call && cur_ops->cb_barrier) { rhp = vmalloc(array3_size(cbflood_n_burst, cbflood_n_per_burst, sizeof(*rhp))); err = !rhp; } if (err) { VERBOSE_TOROUT_STRING("rcu_torture_cbflood disabled: Bad args or OOM"); goto wait_for_stop; } VERBOSE_TOROUT_STRING("rcu_torture_cbflood task started"); do { schedule_timeout_interruptible(cbflood_inter_holdoff); atomic_long_inc(&n_cbfloods); WARN_ON(signal_pending(current)); for (i = 0; i < cbflood_n_burst; i++) { for (j = 0; j < cbflood_n_per_burst; j++) { cur_ops->call(&rhp[i * cbflood_n_per_burst + j], rcu_torture_cbflood_cb); } schedule_timeout_interruptible(cbflood_intra_holdoff); WARN_ON(signal_pending(current)); } cur_ops->cb_barrier(); stutter_wait("rcu_torture_cbflood"); } while (!torture_must_stop()); vfree(rhp); wait_for_stop: torture_kthread_stopping("rcu_torture_cbflood"); 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_TOROUT_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; } stutter_wait("rcu_torture_fqs"); } while (!torture_must_stop()); torture_kthread_stopping("rcu_torture_fqs"); 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 can_expedite = !rcu_gp_is_expedited() && !rcu_gp_is_normal(); int expediting = 0; unsigned long gp_snap; bool gp_cond1 = gp_cond, gp_exp1 = gp_exp, gp_normal1 = gp_normal; bool gp_sync1 = gp_sync; int i; struct rcu_torture *rp; struct rcu_torture *old_rp; static DEFINE_TORTURE_RANDOM(rand); int synctype[] = { RTWS_DEF_FREE, RTWS_EXP_SYNC, RTWS_COND_GET, RTWS_SYNC }; int nsynctypes = 0; VERBOSE_TOROUT_STRING("rcu_torture_writer task started"); if (!can_expedite) pr_alert("%s" TORTURE_FLAG " GP expediting controlled from boot/sysfs for %s.\n", torture_type, cur_ops->name); /* Initialize synctype[] array. If none set, take default. */ if (!gp_cond1 && !gp_exp1 && !gp_normal1 && !gp_sync1) gp_cond1 = gp_exp1 = gp_normal1 = gp_sync1 = true; if (gp_cond1 && cur_ops->get_state && cur_ops->cond_sync) { synctype[nsynctypes++] = RTWS_COND_GET; pr_info("%s: Testing conditional GPs.\n", __func__); } else if (gp_cond && (!cur_ops->get_state || !cur_ops->cond_sync)) { pr_alert("%s: gp_cond without primitives.\n", __func__); } if (gp_exp1 && cur_ops->exp_sync) { synctype[nsynctypes++] = RTWS_EXP_SYNC; pr_info("%s: Testing expedited GPs.\n", __func__); } else if (gp_exp && !cur_ops->exp_sync) { pr_alert("%s: gp_exp without primitives.\n", __func__); } if (gp_normal1 && cur_ops->deferred_free) { synctype[nsynctypes++] = RTWS_DEF_FREE; pr_info("%s: Testing asynchronous GPs.\n", __func__); } else if (gp_normal && !cur_ops->deferred_free) { pr_alert("%s: gp_normal without primitives.\n", __func__); } if (gp_sync1 && cur_ops->sync) { synctype[nsynctypes++] = RTWS_SYNC; pr_info("%s: Testing normal GPs.\n", __func__); } else if (gp_sync && !cur_ops->sync) { pr_alert("%s: gp_sync without primitives.\n", __func__); } if (WARN_ONCE(nsynctypes == 0, "rcu_torture_writer: No update-side primitives.\n")) { /* * No updates primitives, so don't try updating. * The resulting test won't be testing much, hence the * above WARN_ONCE(). */ rcu_torture_writer_state = RTWS_STOPPING; torture_kthread_stopping("rcu_torture_writer"); } do { rcu_torture_writer_state = RTWS_FIXED_DELAY; schedule_timeout_uninterruptible(1); rp = rcu_torture_alloc(); if (rp == NULL) continue; rp->rtort_pipe_count = 0; rcu_torture_writer_state = RTWS_DELAY; udelay(torture_random(&rand) & 0x3ff); rcu_torture_writer_state = RTWS_REPLACE; 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++; switch (synctype[torture_random(&rand) % nsynctypes]) { case RTWS_DEF_FREE: rcu_torture_writer_state = RTWS_DEF_FREE; cur_ops->deferred_free(old_rp); break; case RTWS_EXP_SYNC: rcu_torture_writer_state = RTWS_EXP_SYNC; cur_ops->exp_sync(); rcu_torture_pipe_update(old_rp); break; case RTWS_COND_GET: rcu_torture_writer_state = RTWS_COND_GET; gp_snap = cur_ops->get_state(); i = torture_random(&rand) % 16; if (i != 0) schedule_timeout_interruptible(i); udelay(torture_random(&rand) % 1000); rcu_torture_writer_state = RTWS_COND_SYNC; cur_ops->cond_sync(gp_snap); rcu_torture_pipe_update(old_rp); break; case RTWS_SYNC: rcu_torture_writer_state = RTWS_SYNC; cur_ops->sync(); rcu_torture_pipe_update(old_rp); break; default: WARN_ON_ONCE(1); break; } } rcu_torture_current_version++; /* Cycle through nesting levels of rcu_expedite_gp() calls. */ if (can_expedite && !(torture_random(&rand) & 0xff & (!!expediting - 1))) { WARN_ON_ONCE(expediting == 0 && rcu_gp_is_expedited()); if (expediting >= 0) rcu_expedite_gp(); else rcu_unexpedite_gp(); if (++expediting > 3) expediting = -expediting; } else if (!can_expedite) { /* Disabled during boot, recheck. */ can_expedite = !rcu_gp_is_expedited() && !rcu_gp_is_normal(); } rcu_torture_writer_state = RTWS_STUTTER; stutter_wait("rcu_torture_writer"); } while (!torture_must_stop()); /* Reset expediting back to unexpedited. */ if (expediting > 0) expediting = -expediting; while (can_expedite && expediting++ < 0) rcu_unexpedite_gp(); WARN_ON_ONCE(can_expedite && rcu_gp_is_expedited()); if (!can_expedite) pr_alert("%s" TORTURE_FLAG " Dynamic grace-period expediting was disabled.\n", torture_type); rcu_torture_writer_state = RTWS_STOPPING; torture_kthread_stopping("rcu_torture_writer"); return 0; } /* * RCU torture fake writer kthread. Repeatedly calls sync, with a random * delay between calls. */ static int rcu_torture_fakewriter(void *arg) { DEFINE_TORTURE_RANDOM(rand); VERBOSE_TOROUT_STRING("rcu_torture_fakewriter task started"); set_user_nice(current, MAX_NICE); do { schedule_timeout_uninterruptible(1 + torture_random(&rand)%10); udelay(torture_random(&rand) & 0x3ff); if (cur_ops->cb_barrier != NULL && torture_random(&rand) % (nfakewriters * 8) == 0) { cur_ops->cb_barrier(); } else if (gp_normal == gp_exp) { if (cur_ops->sync && torture_random(&rand) & 0x80) cur_ops->sync(); else if (cur_ops->exp_sync) cur_ops->exp_sync(); } else if (gp_normal && cur_ops->sync) { cur_ops->sync(); } else if (cur_ops->exp_sync) { cur_ops->exp_sync(); } stutter_wait("rcu_torture_fakewriter"); } while (!torture_must_stop()); torture_kthread_stopping("rcu_torture_fakewriter"); return 0; } static void rcu_torture_timer_cb(struct rcu_head *rhp) { kfree(rhp); } /* * Do one extension of an RCU read-side critical section using the * current reader state in readstate (set to zero for initial entry * to extended critical section), set the new state as specified by * newstate (set to zero for final exit from extended critical section), * and random-number-generator state in trsp. If this is neither the * beginning or end of the critical section and if there was actually a * change, do a ->read_delay(). */ static void rcutorture_one_extend(int *readstate, int newstate, struct torture_random_state *trsp) { int idxnew = -1; int idxold = *readstate; int statesnew = ~*readstate & newstate; int statesold = *readstate & ~newstate; WARN_ON_ONCE(idxold < 0); WARN_ON_ONCE((idxold >> RCUTORTURE_RDR_SHIFT) > 1); /* First, put new protection in place to avoid critical-section gap. */ if (statesnew & RCUTORTURE_RDR_BH) local_bh_disable(); if (statesnew & RCUTORTURE_RDR_IRQ) local_irq_disable(); if (statesnew & RCUTORTURE_RDR_PREEMPT) preempt_disable(); if (statesnew & RCUTORTURE_RDR_RCU) idxnew = cur_ops->readlock() << RCUTORTURE_RDR_SHIFT; /* Next, remove old protection, irq first due to bh conflict. */ if (statesold & RCUTORTURE_RDR_IRQ) local_irq_enable(); if (statesold & RCUTORTURE_RDR_BH) local_bh_enable(); if (statesold & RCUTORTURE_RDR_PREEMPT) preempt_enable(); if (statesold & RCUTORTURE_RDR_RCU) cur_ops->readunlock(idxold >> RCUTORTURE_RDR_SHIFT); /* Delay if neither beginning nor end and there was a change. */ if ((statesnew || statesold) && *readstate && newstate) cur_ops->read_delay(trsp); /* Update the reader state. */ if (idxnew == -1) idxnew = idxold & ~RCUTORTURE_RDR_MASK; WARN_ON_ONCE(idxnew < 0); WARN_ON_ONCE((idxnew >> RCUTORTURE_RDR_SHIFT) > 1); *readstate = idxnew | newstate; WARN_ON_ONCE((*readstate >> RCUTORTURE_RDR_SHIFT) < 0); WARN_ON_ONCE((*readstate >> RCUTORTURE_RDR_SHIFT) > 1); } /* Return the biggest extendables mask given current RCU and boot parameters. */ static int rcutorture_extend_mask_max(void) { int mask; WARN_ON_ONCE(extendables & ~RCUTORTURE_MAX_EXTEND); mask = extendables & RCUTORTURE_MAX_EXTEND & cur_ops->extendables; mask = mask | RCUTORTURE_RDR_RCU; return mask; } /* Return a random protection state mask, but with at least one bit set. */ static int rcutorture_extend_mask(int oldmask, struct torture_random_state *trsp) { int mask = rcutorture_extend_mask_max(); unsigned long randmask1 = torture_random(trsp) >> 8; unsigned long randmask2 = randmask1 >> 1; WARN_ON_ONCE(mask >> RCUTORTURE_RDR_SHIFT); /* Half the time lots of bits, half the time only one bit. */ if (randmask1 & 0x1) mask = mask & randmask2; else mask = mask & (1 << (randmask2 % RCUTORTURE_RDR_NBITS)); if ((mask & RCUTORTURE_RDR_IRQ) && !(mask & RCUTORTURE_RDR_BH) && (oldmask & RCUTORTURE_RDR_BH)) mask |= RCUTORTURE_RDR_BH; /* Can't enable bh w/irq disabled. */ if ((mask & RCUTORTURE_RDR_IRQ) && !(mask & cur_ops->ext_irq_conflict) && (oldmask & cur_ops->ext_irq_conflict)) mask |= cur_ops->ext_irq_conflict; /* Or if readers object. */ return mask ?: RCUTORTURE_RDR_RCU; } /* * Do a randomly selected number of extensions of an existing RCU read-side * critical section. */ static void rcutorture_loop_extend(int *readstate, struct torture_random_state *trsp) { int i; int mask = rcutorture_extend_mask_max(); WARN_ON_ONCE(!*readstate); /* -Existing- RCU read-side critsect! */ if (!((mask - 1) & mask)) return; /* Current RCU flavor not extendable. */ i = (torture_random(trsp) >> 3) & RCUTORTURE_RDR_MAX_LOOPS; while (i--) { mask = rcutorture_extend_mask(*readstate, trsp); rcutorture_one_extend(readstate, mask, trsp); } } /* * Do one read-side critical section, returning false if there was * no data to read. Can be invoked both from process context and * from a timer handler. */ static bool rcu_torture_one_read(struct torture_random_state *trsp) { unsigned long started; unsigned long completed; int newstate; struct rcu_torture *p; int pipe_count; int readstate = 0; unsigned long long ts; newstate = rcutorture_extend_mask(readstate, trsp); rcutorture_one_extend(&readstate, newstate, trsp); started = cur_ops->get_gp_seq(); 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_ctlp) || torturing_tasks()); if (p == NULL) { /* Wait for rcu_torture_writer to get underway */ rcutorture_one_extend(&readstate, 0, trsp); return false; } if (p->rtort_mbtest == 0) atomic_inc(&n_rcu_torture_mberror); rcutorture_loop_extend(&readstate, trsp); 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 = cur_ops->get_gp_seq(); if (pipe_count > 1) { do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts, started, completed); rcu_ftrace_dump(DUMP_ALL); } __this_cpu_inc(rcu_torture_count[pipe_count]); completed = rcutorture_seq_diff(completed, started); if (completed > RCU_TORTURE_PIPE_LEN) { /* Should not happen, but... */ completed = RCU_TORTURE_PIPE_LEN; } __this_cpu_inc(rcu_torture_batch[completed]); preempt_enable(); rcutorture_one_extend(&readstate, 0, trsp); WARN_ON_ONCE(readstate & RCUTORTURE_RDR_MASK); return true; } static DEFINE_TORTURE_RANDOM_PERCPU(rcu_torture_timer_rand); /* * 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(struct timer_list *unused) { atomic_long_inc(&n_rcu_torture_timers); (void)rcu_torture_one_read(this_cpu_ptr(&rcu_torture_timer_rand)); /* Test call_rcu() invocation from interrupt handler. */ if (cur_ops->call) { struct rcu_head *rhp = kmalloc(sizeof(*rhp), GFP_NOWAIT); if (rhp) cur_ops->call(rhp, rcu_torture_timer_cb); } } /* * 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) { DEFINE_TORTURE_RANDOM(rand); struct timer_list t; VERBOSE_TOROUT_STRING("rcu_torture_reader task started"); set_user_nice(current, MAX_NICE); if (irqreader && cur_ops->irq_capable) timer_setup_on_stack(&t, rcu_torture_timer, 0); do { if (irqreader && cur_ops->irq_capable) { if (!timer_pending(&t)) mod_timer(&t, jiffies + 1); } if (!rcu_torture_one_read(&rand)) schedule_timeout_interruptible(HZ); stutter_wait("rcu_torture_reader"); } while (!torture_must_stop()); if (irqreader && cur_ops->irq_capable) { del_timer_sync(&t); destroy_timer_on_stack(&t); } torture_kthread_stopping("rcu_torture_reader"); return 0; } /* * 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 cpu; int i; long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; static unsigned long rtcv_snap = ULONG_MAX; static bool splatted; struct task_struct *wtp; 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; } pr_alert("%s%s ", torture_type, TORTURE_FLAG); pr_cont("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)); pr_cont("rtmbe: %d rtbe: %ld rtbke: %ld rtbre: %ld ", atomic_read(&n_rcu_torture_mberror), n_rcu_torture_barrier_error, n_rcu_torture_boost_ktrerror, n_rcu_torture_boost_rterror); pr_cont("rtbf: %ld rtb: %ld nt: %ld ", n_rcu_torture_boost_failure, n_rcu_torture_boosts, atomic_long_read(&n_rcu_torture_timers)); torture_onoff_stats(); pr_cont("barrier: %ld/%ld:%ld ", n_barrier_successes, n_barrier_attempts, n_rcu_torture_barrier_error); pr_cont("cbflood: %ld\n", atomic_long_read(&n_cbfloods)); pr_alert("%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) { pr_cont("%s", "!!! "); atomic_inc(&n_rcu_torture_error); WARN_ON_ONCE(1); } pr_cont("Reader Pipe: "); for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) pr_cont(" %ld", pipesummary[i]); pr_cont("\n"); pr_alert("%s%s ", torture_type, TORTURE_FLAG); pr_cont("Reader Batch: "); for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) pr_cont(" %ld", batchsummary[i]); pr_cont("\n"); pr_alert("%s%s ", torture_type, TORTURE_FLAG); pr_cont("Free-Block Circulation: "); for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { pr_cont(" %d", atomic_read(&rcu_torture_wcount[i])); } pr_cont("\n"); if (cur_ops->stats) cur_ops->stats(); if (rtcv_snap == rcu_torture_current_version && rcu_torture_current != NULL) { int __maybe_unused flags = 0; unsigned long __maybe_unused gp_seq = 0; rcutorture_get_gp_data(cur_ops->ttype, &flags, &gp_seq); srcutorture_get_gp_data(cur_ops->ttype, srcu_ctlp, &flags, &gp_seq); wtp = READ_ONCE(writer_task); pr_alert("??? Writer stall state %s(%d) g%lu f%#x ->state %#lx cpu %d\n", rcu_torture_writer_state_getname(), rcu_torture_writer_state, gp_seq, flags, wtp == NULL ? ~0UL : wtp->state, wtp == NULL ? -1 : (int)task_cpu(wtp)); if (!splatted && wtp) { sched_show_task(wtp); splatted = true; } show_rcu_gp_kthreads(); rcu_ftrace_dump(DUMP_ALL); } rtcv_snap = rcu_torture_current_version; } /* * Periodically prints torture statistics, if periodic statistics printing * was specified via the stat_interval module parameter. */ static int rcu_torture_stats(void *arg) { VERBOSE_TOROUT_STRING("rcu_torture_stats task started"); do { schedule_timeout_interruptible(stat_interval * HZ); rcu_torture_stats_print(); torture_shutdown_absorb("rcu_torture_stats"); } while (!torture_must_stop()); torture_kthread_stopping("rcu_torture_stats"); return 0; } static 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 stall_cpu_irqsoff=%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, stall_cpu_irqsoff, n_barrier_cbs, onoff_interval, onoff_holdoff); } static int rcutorture_booster_cleanup(unsigned int cpu) { struct task_struct *t; if (boost_tasks[cpu] == NULL) return 0; mutex_lock(&boost_mutex); t = boost_tasks[cpu]; boost_tasks[cpu] = NULL; rcu_torture_enable_rt_throttle(); mutex_unlock(&boost_mutex); /* This must be outside of the mutex, otherwise deadlock! */ torture_stop_kthread(rcu_torture_boost, t); return 0; } static int rcutorture_booster_init(unsigned 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); rcu_torture_disable_rt_throttle(); VERBOSE_TOROUT_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_TOROUT_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; } /* * 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_TOROUT_STRING("rcu_torture_stall task started"); if (stall_cpu_holdoff > 0) { VERBOSE_TOROUT_STRING("rcu_torture_stall begin holdoff"); schedule_timeout_interruptible(stall_cpu_holdoff * HZ); VERBOSE_TOROUT_STRING("rcu_torture_stall end holdoff"); } if (!kthread_should_stop()) { stop_at = ktime_get_seconds() + stall_cpu; /* RCU CPU stall is expected behavior in following code. */ rcu_read_lock(); if (stall_cpu_irqsoff) local_irq_disable(); else preempt_disable(); pr_alert("rcu_torture_stall start on CPU %d.\n", smp_processor_id()); while (ULONG_CMP_LT((unsigned long)ktime_get_seconds(), stop_at)) continue; /* Induce RCU CPU stall warning. */ if (stall_cpu_irqsoff) local_irq_enable(); else preempt_enable(); rcu_read_unlock(); pr_alert("rcu_torture_stall end.\n"); } torture_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) { if (stall_cpu <= 0) return 0; return torture_create_kthread(rcu_torture_stall, NULL, stall_task); } /* Callback function for RCU barrier testing. */ static 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; bool newphase; struct rcu_head rcu; init_rcu_head_on_stack(&rcu); VERBOSE_TOROUT_STRING("rcu_torture_barrier_cbs task started"); set_user_nice(current, MAX_NICE); do { wait_event(barrier_cbs_wq[myid], (newphase = smp_load_acquire(&barrier_phase)) != lastphase || torture_must_stop()); lastphase = newphase; if (torture_must_stop()) break; /* * The above smp_load_acquire() ensures barrier_phase load * is ordered before the following ->call(). */ local_irq_disable(); /* Just to test no-irq call_rcu(). */ cur_ops->call(&rcu, rcu_torture_barrier_cbf); local_irq_enable(); if (atomic_dec_and_test(&barrier_cbs_count)) wake_up(&barrier_wq); } while (!torture_must_stop()); if (cur_ops->cb_barrier != NULL) cur_ops->cb_barrier(); destroy_rcu_head_on_stack(&rcu); torture_kthread_stopping("rcu_torture_barrier_cbs"); return 0; } /* kthread function to drive and coordinate RCU barrier testing. */ static int rcu_torture_barrier(void *arg) { int i; VERBOSE_TOROUT_STRING("rcu_torture_barrier task starting"); do { atomic_set(&barrier_cbs_invoked, 0); atomic_set(&barrier_cbs_count, n_barrier_cbs); /* Ensure barrier_phase ordered after prior assignments. */ smp_store_release(&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 || torture_must_stop()); if (torture_must_stop()) break; n_barrier_attempts++; cur_ops->cb_barrier(); /* Implies smp_mb() for wait_event(). */ if (atomic_read(&barrier_cbs_invoked) != n_barrier_cbs) { n_rcu_torture_barrier_error++; pr_err("barrier_cbs_invoked = %d, n_barrier_cbs = %d\n", atomic_read(&barrier_cbs_invoked), n_barrier_cbs); WARN_ON_ONCE(1); } else { n_barrier_successes++; } schedule_timeout_interruptible(HZ / 10); } while (!torture_must_stop()); torture_kthread_stopping("rcu_torture_barrier"); 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 = kcalloc(n_barrier_cbs, sizeof(barrier_cbs_tasks[0]), GFP_KERNEL); barrier_cbs_wq = kcalloc(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]); ret = torture_create_kthread(rcu_torture_barrier_cbs, (void *)(long)i, barrier_cbs_tasks[i]); if (ret) return ret; } return torture_create_kthread(rcu_torture_barrier, NULL, barrier_task); } /* Clean up after RCU barrier testing. */ static void rcu_torture_barrier_cleanup(void) { int i; torture_stop_kthread(rcu_torture_barrier, barrier_task); if (barrier_cbs_tasks != NULL) { for (i = 0; i < n_barrier_cbs; i++) torture_stop_kthread(rcu_torture_barrier_cbs, barrier_cbs_tasks[i]); kfree(barrier_cbs_tasks); barrier_cbs_tasks = NULL; } if (barrier_cbs_wq != NULL) { kfree(barrier_cbs_wq); barrier_cbs_wq = NULL; } } static bool rcu_torture_can_boost(void) { static int boost_warn_once; int prio; if (!(test_boost == 1 && cur_ops->can_boost) && test_boost != 2) return false; prio = rcu_get_gp_kthreads_prio(); if (!prio) return false; if (prio < 2) { if (boost_warn_once == 1) return false; pr_alert("%s: WARN: RCU kthread priority too low to test boosting. Skipping RCU boost test. Try passing rcutree.kthread_prio > 1 on the kernel command line.\n", KBUILD_MODNAME); boost_warn_once = 1; return false; } return true; } static enum cpuhp_state rcutor_hp; static void rcu_torture_cleanup(void) { int flags = 0; unsigned long gp_seq = 0; int i; if (torture_cleanup_begin()) { if (cur_ops->cb_barrier != NULL) cur_ops->cb_barrier(); return; } rcu_torture_barrier_cleanup(); torture_stop_kthread(rcu_torture_stall, stall_task); torture_stop_kthread(rcu_torture_writer, writer_task); if (reader_tasks) { for (i = 0; i < nrealreaders; i++) torture_stop_kthread(rcu_torture_reader, reader_tasks[i]); kfree(reader_tasks); } rcu_torture_current = NULL; if (fakewriter_tasks) { for (i = 0; i < nfakewriters; i++) { torture_stop_kthread(rcu_torture_fakewriter, fakewriter_tasks[i]); } kfree(fakewriter_tasks); fakewriter_tasks = NULL; } rcutorture_get_gp_data(cur_ops->ttype, &flags, &gp_seq); srcutorture_get_gp_data(cur_ops->ttype, srcu_ctlp, &flags, &gp_seq); pr_alert("%s: End-test grace-period state: g%lu f%#x\n", cur_ops->name, gp_seq, flags); torture_stop_kthread(rcu_torture_stats, stats_task); torture_stop_kthread(rcu_torture_fqs, fqs_task); for (i = 0; i < ncbflooders; i++) torture_stop_kthread(rcu_torture_cbflood, cbflood_task[i]); if (rcu_torture_can_boost()) cpuhp_remove_state(rcutor_hp); /* * Wait for all RCU callbacks to fire, then do flavor-specific * cleanup operations. */ if (cur_ops->cb_barrier != NULL) cur_ops->cb_barrier(); if (cur_ops->cleanup != NULL) cur_ops->cleanup(); 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 (torture_onoff_failures()) rcu_torture_print_module_parms(cur_ops, "End of test: RCU_HOTPLUG"); else rcu_torture_print_module_parms(cur_ops, "End of test: SUCCESS"); torture_cleanup_end(); } #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("%s: duplicated callback was invoked.\n", KBUILD_MODNAME); } #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("%s: WARN: Duplicate call_rcu() test starting.\n", KBUILD_MODNAME); /* 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("%s: WARN: Duplicate call_rcu() test complete.\n", KBUILD_MODNAME); destroy_rcu_head_on_stack(&rh1); destroy_rcu_head_on_stack(&rh2); #else /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ pr_alert("%s: !CONFIG_DEBUG_OBJECTS_RCU_HEAD, not testing duplicate call_rcu()\n", KBUILD_MODNAME); #endif /* #else #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ } static int __init rcu_torture_init(void) { int i; int cpu; int firsterr = 0; static struct rcu_torture_ops *torture_ops[] = { &rcu_ops, &rcu_bh_ops, &rcu_busted_ops, &srcu_ops, &srcud_ops, &busted_srcud_ops, &sched_ops, &tasks_ops, }; if (!torture_init_begin(torture_type, verbose)) return -EBUSY; /* Process args and tell the world that the torturer is on the job. */ for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { 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_cont(" %s", torture_ops[i]->name); pr_cont("\n"); firsterr = -EINVAL; goto unwind; } 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(); if (nreaders >= 0) { nrealreaders = nreaders; } else { nrealreaders = num_online_cpus() - 2 - nreaders; if (nrealreaders <= 0) nrealreaders = 1; } rcu_torture_print_module_parms(cur_ops, "Start of test"); /* 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. */ firsterr = torture_create_kthread(rcu_torture_writer, NULL, writer_task); if (firsterr) goto unwind; if (nfakewriters > 0) { fakewriter_tasks = kcalloc(nfakewriters, sizeof(fakewriter_tasks[0]), GFP_KERNEL); if (fakewriter_tasks == NULL) { VERBOSE_TOROUT_ERRSTRING("out of memory"); firsterr = -ENOMEM; goto unwind; } } for (i = 0; i < nfakewriters; i++) { firsterr = torture_create_kthread(rcu_torture_fakewriter, NULL, fakewriter_tasks[i]); if (firsterr) goto unwind; } reader_tasks = kcalloc(nrealreaders, sizeof(reader_tasks[0]), GFP_KERNEL); if (reader_tasks == NULL) { VERBOSE_TOROUT_ERRSTRING("out of memory"); firsterr = -ENOMEM; goto unwind; } for (i = 0; i < nrealreaders; i++) { firsterr = torture_create_kthread(rcu_torture_reader, NULL, reader_tasks[i]); if (firsterr) goto unwind; } if (stat_interval > 0) { firsterr = torture_create_kthread(rcu_torture_stats, NULL, stats_task); if (firsterr) goto unwind; } if (test_no_idle_hz && shuffle_interval > 0) { firsterr = torture_shuffle_init(shuffle_interval * HZ); if (firsterr) goto unwind; } if (stutter < 0) stutter = 0; if (stutter) { firsterr = torture_stutter_init(stutter * HZ); if (firsterr) goto unwind; } if (fqs_duration < 0) fqs_duration = 0; if (fqs_duration) { /* Create the fqs thread */ firsterr = torture_create_kthread(rcu_torture_fqs, NULL, fqs_task); if (firsterr) goto unwind; } if (test_boost_interval < 1) test_boost_interval = 1; if (test_boost_duration < 2) test_boost_duration = 2; if (rcu_torture_can_boost()) { boost_starttime = jiffies + test_boost_interval * HZ; firsterr = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "RCU_TORTURE", rcutorture_booster_init, rcutorture_booster_cleanup); if (firsterr < 0) goto unwind; rcutor_hp = firsterr; } firsterr = torture_shutdown_init(shutdown_secs, rcu_torture_cleanup); if (firsterr) goto unwind; firsterr = torture_onoff_init(onoff_holdoff * HZ, onoff_interval); if (firsterr) goto unwind; firsterr = rcu_torture_stall_init(); if (firsterr) goto unwind; firsterr = rcu_torture_barrier_init(); if (firsterr) goto unwind; if (object_debug) rcu_test_debug_objects(); if (cbflood_n_burst > 0) { /* Create the cbflood threads */ ncbflooders = (num_online_cpus() + 3) / 4; cbflood_task = kcalloc(ncbflooders, sizeof(*cbflood_task), GFP_KERNEL); if (!cbflood_task) { VERBOSE_TOROUT_ERRSTRING("out of memory"); firsterr = -ENOMEM; goto unwind; } for (i = 0; i < ncbflooders; i++) { firsterr = torture_create_kthread(rcu_torture_cbflood, NULL, cbflood_task[i]); if (firsterr) goto unwind; } } torture_init_end(); return 0; unwind: torture_init_end(); rcu_torture_cleanup(); return firsterr; } module_init(rcu_torture_init); module_exit(rcu_torture_cleanup);
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with Cregit http://github.com/cregit/cregit
Version 2.0-RC1