Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 1 | /* |
Paul E. McKenney | 29766f1 | 2006-06-27 02:54:02 -0700 | [diff] [blame] | 2 | * Read-Copy Update module-based torture test facility |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, write to the Free Software |
| 16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 17 | * |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 18 | * Copyright (C) IBM Corporation, 2005, 2006 |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 19 | * |
| 20 | * Authors: Paul E. McKenney <paulmck@us.ibm.com> |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 21 | * Josh Triplett <josh@freedesktop.org> |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 22 | * |
| 23 | * See also: Documentation/RCU/torture.txt |
| 24 | */ |
| 25 | #include <linux/types.h> |
| 26 | #include <linux/kernel.h> |
| 27 | #include <linux/init.h> |
| 28 | #include <linux/module.h> |
| 29 | #include <linux/kthread.h> |
| 30 | #include <linux/err.h> |
| 31 | #include <linux/spinlock.h> |
| 32 | #include <linux/smp.h> |
| 33 | #include <linux/rcupdate.h> |
| 34 | #include <linux/interrupt.h> |
| 35 | #include <linux/sched.h> |
| 36 | #include <asm/atomic.h> |
| 37 | #include <linux/bitops.h> |
| 38 | #include <linux/module.h> |
| 39 | #include <linux/completion.h> |
| 40 | #include <linux/moduleparam.h> |
| 41 | #include <linux/percpu.h> |
| 42 | #include <linux/notifier.h> |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 43 | #include <linux/cpu.h> |
| 44 | #include <linux/random.h> |
| 45 | #include <linux/delay.h> |
| 46 | #include <linux/byteorder/swabb.h> |
| 47 | #include <linux/stat.h> |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 48 | #include <linux/srcu.h> |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 49 | |
| 50 | MODULE_LICENSE("GPL"); |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 51 | MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and " |
| 52 | "Josh Triplett <josh@freedesktop.org>"); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 53 | |
Josh Triplett | 4802211 | 2006-10-03 23:26:16 +0200 | [diff] [blame] | 54 | static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */ |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 55 | static int nfakewriters = 4; /* # fake writer threads */ |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 56 | static int stat_interval; /* Interval between stats, in seconds. */ |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 57 | /* Defaults to "only at end of test". */ |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 58 | static int verbose; /* Print more debug info. */ |
| 59 | static int test_no_idle_hz; /* Test RCU's support for tickless idle CPUs. */ |
| 60 | static int shuffle_interval = 5; /* Interval between shuffles (in sec)*/ |
Josh Triplett | 20d2e42 | 2006-10-04 02:17:15 -0700 | [diff] [blame] | 61 | static char *torture_type = "rcu"; /* What RCU implementation to torture. */ |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 62 | |
Josh Triplett | d6ad671 | 2007-03-06 01:42:13 -0800 | [diff] [blame] | 63 | module_param(nreaders, int, 0444); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 64 | MODULE_PARM_DESC(nreaders, "Number of RCU reader threads"); |
Josh Triplett | d6ad671 | 2007-03-06 01:42:13 -0800 | [diff] [blame] | 65 | module_param(nfakewriters, int, 0444); |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 66 | MODULE_PARM_DESC(nfakewriters, "Number of RCU fake writer threads"); |
Josh Triplett | d6ad671 | 2007-03-06 01:42:13 -0800 | [diff] [blame] | 67 | module_param(stat_interval, int, 0444); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 68 | MODULE_PARM_DESC(stat_interval, "Number of seconds between stats printk()s"); |
Josh Triplett | d6ad671 | 2007-03-06 01:42:13 -0800 | [diff] [blame] | 69 | module_param(verbose, bool, 0444); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 70 | MODULE_PARM_DESC(verbose, "Enable verbose debugging printk()s"); |
Josh Triplett | d6ad671 | 2007-03-06 01:42:13 -0800 | [diff] [blame] | 71 | module_param(test_no_idle_hz, bool, 0444); |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 72 | MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs"); |
Josh Triplett | d6ad671 | 2007-03-06 01:42:13 -0800 | [diff] [blame] | 73 | module_param(shuffle_interval, int, 0444); |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 74 | MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles"); |
Josh Triplett | d6ad671 | 2007-03-06 01:42:13 -0800 | [diff] [blame] | 75 | module_param(torture_type, charp, 0444); |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 76 | MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, srcu)"); |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 77 | |
| 78 | #define TORTURE_FLAG "-torture:" |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 79 | #define PRINTK_STRING(s) \ |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 80 | do { printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 81 | #define VERBOSE_PRINTK_STRING(s) \ |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 82 | do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG s "\n", torture_type); } while (0) |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 83 | #define VERBOSE_PRINTK_ERRSTRING(s) \ |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 84 | do { if (verbose) printk(KERN_ALERT "%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 85 | |
| 86 | static char printk_buf[4096]; |
| 87 | |
| 88 | static int nrealreaders; |
| 89 | static struct task_struct *writer_task; |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 90 | static struct task_struct **fakewriter_tasks; |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 91 | static struct task_struct **reader_tasks; |
| 92 | static struct task_struct *stats_task; |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 93 | static struct task_struct *shuffler_task; |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 94 | |
| 95 | #define RCU_TORTURE_PIPE_LEN 10 |
| 96 | |
| 97 | struct rcu_torture { |
| 98 | struct rcu_head rtort_rcu; |
| 99 | int rtort_pipe_count; |
| 100 | struct list_head rtort_free; |
Paul E. McKenney | 996417d | 2005-11-18 01:10:50 -0800 | [diff] [blame] | 101 | int rtort_mbtest; |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 102 | }; |
| 103 | |
| 104 | static int fullstop = 0; /* stop generating callbacks at test end. */ |
| 105 | static LIST_HEAD(rcu_torture_freelist); |
| 106 | static struct rcu_torture *rcu_torture_current = NULL; |
| 107 | static long rcu_torture_current_version = 0; |
| 108 | static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN]; |
| 109 | static DEFINE_SPINLOCK(rcu_torture_lock); |
| 110 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) = |
| 111 | { 0 }; |
| 112 | static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch) = |
| 113 | { 0 }; |
| 114 | static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1]; |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 115 | static atomic_t n_rcu_torture_alloc; |
| 116 | static atomic_t n_rcu_torture_alloc_fail; |
| 117 | static atomic_t n_rcu_torture_free; |
| 118 | static atomic_t n_rcu_torture_mberror; |
| 119 | static atomic_t n_rcu_torture_error; |
Josh Triplett | e303373 | 2006-10-04 02:17:14 -0700 | [diff] [blame] | 120 | static struct list_head rcu_torture_removed; |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 121 | |
| 122 | /* |
| 123 | * Allocate an element from the rcu_tortures pool. |
| 124 | */ |
Adrian Bunk | 97a41e2 | 2006-01-08 01:02:17 -0800 | [diff] [blame] | 125 | static struct rcu_torture * |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 126 | rcu_torture_alloc(void) |
| 127 | { |
| 128 | struct list_head *p; |
| 129 | |
Ingo Molnar | adac166 | 2006-01-25 19:50:12 +0100 | [diff] [blame] | 130 | spin_lock_bh(&rcu_torture_lock); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 131 | if (list_empty(&rcu_torture_freelist)) { |
| 132 | atomic_inc(&n_rcu_torture_alloc_fail); |
Ingo Molnar | adac166 | 2006-01-25 19:50:12 +0100 | [diff] [blame] | 133 | spin_unlock_bh(&rcu_torture_lock); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 134 | return NULL; |
| 135 | } |
| 136 | atomic_inc(&n_rcu_torture_alloc); |
| 137 | p = rcu_torture_freelist.next; |
| 138 | list_del_init(p); |
Ingo Molnar | adac166 | 2006-01-25 19:50:12 +0100 | [diff] [blame] | 139 | spin_unlock_bh(&rcu_torture_lock); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 140 | return container_of(p, struct rcu_torture, rtort_free); |
| 141 | } |
| 142 | |
| 143 | /* |
| 144 | * Free an element to the rcu_tortures pool. |
| 145 | */ |
| 146 | static void |
| 147 | rcu_torture_free(struct rcu_torture *p) |
| 148 | { |
| 149 | atomic_inc(&n_rcu_torture_free); |
Ingo Molnar | adac166 | 2006-01-25 19:50:12 +0100 | [diff] [blame] | 150 | spin_lock_bh(&rcu_torture_lock); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 151 | list_add_tail(&p->rtort_free, &rcu_torture_freelist); |
Ingo Molnar | adac166 | 2006-01-25 19:50:12 +0100 | [diff] [blame] | 152 | spin_unlock_bh(&rcu_torture_lock); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 153 | } |
| 154 | |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 155 | struct rcu_random_state { |
| 156 | unsigned long rrs_state; |
Josh Triplett | 75cfef3 | 2006-10-04 02:17:12 -0700 | [diff] [blame] | 157 | long rrs_count; |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 158 | }; |
| 159 | |
| 160 | #define RCU_RANDOM_MULT 39916801 /* prime */ |
| 161 | #define RCU_RANDOM_ADD 479001701 /* prime */ |
| 162 | #define RCU_RANDOM_REFRESH 10000 |
| 163 | |
| 164 | #define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 } |
| 165 | |
| 166 | /* |
| 167 | * Crude but fast random-number generator. Uses a linear congruential |
| 168 | * generator, with occasional help from get_random_bytes(). |
| 169 | */ |
Josh Triplett | 75cfef3 | 2006-10-04 02:17:12 -0700 | [diff] [blame] | 170 | static unsigned long |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 171 | rcu_random(struct rcu_random_state *rrsp) |
| 172 | { |
| 173 | long refresh; |
| 174 | |
| 175 | if (--rrsp->rrs_count < 0) { |
| 176 | get_random_bytes(&refresh, sizeof(refresh)); |
| 177 | rrsp->rrs_state += refresh; |
| 178 | rrsp->rrs_count = RCU_RANDOM_REFRESH; |
| 179 | } |
| 180 | rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD; |
| 181 | return swahw32(rrsp->rrs_state); |
| 182 | } |
| 183 | |
| 184 | /* |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 185 | * Operations vector for selecting different types of tests. |
| 186 | */ |
| 187 | |
| 188 | struct rcu_torture_ops { |
| 189 | void (*init)(void); |
| 190 | void (*cleanup)(void); |
| 191 | int (*readlock)(void); |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 192 | void (*readdelay)(struct rcu_random_state *rrsp); |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 193 | void (*readunlock)(int idx); |
| 194 | int (*completed)(void); |
| 195 | void (*deferredfree)(struct rcu_torture *p); |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 196 | void (*sync)(void); |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 197 | int (*stats)(char *page); |
| 198 | char *name; |
| 199 | }; |
| 200 | static struct rcu_torture_ops *cur_ops = NULL; |
| 201 | |
| 202 | /* |
| 203 | * Definitions for rcu torture testing. |
| 204 | */ |
| 205 | |
Josh Triplett | a49a4af | 2006-09-29 01:59:30 -0700 | [diff] [blame] | 206 | static int rcu_torture_read_lock(void) __acquires(RCU) |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 207 | { |
| 208 | rcu_read_lock(); |
| 209 | return 0; |
| 210 | } |
| 211 | |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 212 | static void rcu_read_delay(struct rcu_random_state *rrsp) |
| 213 | { |
| 214 | long delay; |
| 215 | const long longdelay = 200; |
| 216 | |
| 217 | /* We want there to be long-running readers, but not all the time. */ |
| 218 | |
| 219 | delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay); |
| 220 | if (!delay) |
| 221 | udelay(longdelay); |
| 222 | } |
| 223 | |
Josh Triplett | a49a4af | 2006-09-29 01:59:30 -0700 | [diff] [blame] | 224 | static void rcu_torture_read_unlock(int idx) __releases(RCU) |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 225 | { |
| 226 | rcu_read_unlock(); |
| 227 | } |
| 228 | |
| 229 | static int rcu_torture_completed(void) |
| 230 | { |
| 231 | return rcu_batches_completed(); |
| 232 | } |
| 233 | |
| 234 | static void |
| 235 | rcu_torture_cb(struct rcu_head *p) |
| 236 | { |
| 237 | int i; |
| 238 | struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu); |
| 239 | |
| 240 | if (fullstop) { |
| 241 | /* Test is ending, just drop callbacks on the floor. */ |
| 242 | /* The next initialization will pick up the pieces. */ |
| 243 | return; |
| 244 | } |
| 245 | i = rp->rtort_pipe_count; |
| 246 | if (i > RCU_TORTURE_PIPE_LEN) |
| 247 | i = RCU_TORTURE_PIPE_LEN; |
| 248 | atomic_inc(&rcu_torture_wcount[i]); |
| 249 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { |
| 250 | rp->rtort_mbtest = 0; |
| 251 | rcu_torture_free(rp); |
| 252 | } else |
| 253 | cur_ops->deferredfree(rp); |
| 254 | } |
| 255 | |
| 256 | static void rcu_torture_deferred_free(struct rcu_torture *p) |
| 257 | { |
| 258 | call_rcu(&p->rtort_rcu, rcu_torture_cb); |
| 259 | } |
| 260 | |
| 261 | static struct rcu_torture_ops rcu_ops = { |
| 262 | .init = NULL, |
| 263 | .cleanup = NULL, |
| 264 | .readlock = rcu_torture_read_lock, |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 265 | .readdelay = rcu_read_delay, |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 266 | .readunlock = rcu_torture_read_unlock, |
| 267 | .completed = rcu_torture_completed, |
| 268 | .deferredfree = rcu_torture_deferred_free, |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 269 | .sync = synchronize_rcu, |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 270 | .stats = NULL, |
| 271 | .name = "rcu" |
| 272 | }; |
| 273 | |
Josh Triplett | e303373 | 2006-10-04 02:17:14 -0700 | [diff] [blame] | 274 | static void rcu_sync_torture_deferred_free(struct rcu_torture *p) |
| 275 | { |
| 276 | int i; |
| 277 | struct rcu_torture *rp; |
| 278 | struct rcu_torture *rp1; |
| 279 | |
| 280 | cur_ops->sync(); |
| 281 | list_add(&p->rtort_free, &rcu_torture_removed); |
| 282 | list_for_each_entry_safe(rp, rp1, &rcu_torture_removed, rtort_free) { |
| 283 | i = rp->rtort_pipe_count; |
| 284 | if (i > RCU_TORTURE_PIPE_LEN) |
| 285 | i = RCU_TORTURE_PIPE_LEN; |
| 286 | atomic_inc(&rcu_torture_wcount[i]); |
| 287 | if (++rp->rtort_pipe_count >= RCU_TORTURE_PIPE_LEN) { |
| 288 | rp->rtort_mbtest = 0; |
| 289 | list_del(&rp->rtort_free); |
| 290 | rcu_torture_free(rp); |
| 291 | } |
| 292 | } |
| 293 | } |
| 294 | |
| 295 | static void rcu_sync_torture_init(void) |
| 296 | { |
| 297 | INIT_LIST_HEAD(&rcu_torture_removed); |
| 298 | } |
| 299 | |
Josh Triplett | 20d2e42 | 2006-10-04 02:17:15 -0700 | [diff] [blame] | 300 | static struct rcu_torture_ops rcu_sync_ops = { |
| 301 | .init = rcu_sync_torture_init, |
| 302 | .cleanup = NULL, |
| 303 | .readlock = rcu_torture_read_lock, |
| 304 | .readdelay = rcu_read_delay, |
| 305 | .readunlock = rcu_torture_read_unlock, |
| 306 | .completed = rcu_torture_completed, |
| 307 | .deferredfree = rcu_sync_torture_deferred_free, |
| 308 | .sync = synchronize_rcu, |
| 309 | .stats = NULL, |
| 310 | .name = "rcu_sync" |
| 311 | }; |
| 312 | |
Paul E. McKenney | c32e066 | 2006-06-27 02:54:04 -0700 | [diff] [blame] | 313 | /* |
| 314 | * Definitions for rcu_bh torture testing. |
| 315 | */ |
| 316 | |
Josh Triplett | a49a4af | 2006-09-29 01:59:30 -0700 | [diff] [blame] | 317 | static int rcu_bh_torture_read_lock(void) __acquires(RCU_BH) |
Paul E. McKenney | c32e066 | 2006-06-27 02:54:04 -0700 | [diff] [blame] | 318 | { |
| 319 | rcu_read_lock_bh(); |
| 320 | return 0; |
| 321 | } |
| 322 | |
Josh Triplett | a49a4af | 2006-09-29 01:59:30 -0700 | [diff] [blame] | 323 | static void rcu_bh_torture_read_unlock(int idx) __releases(RCU_BH) |
Paul E. McKenney | c32e066 | 2006-06-27 02:54:04 -0700 | [diff] [blame] | 324 | { |
| 325 | rcu_read_unlock_bh(); |
| 326 | } |
| 327 | |
| 328 | static int rcu_bh_torture_completed(void) |
| 329 | { |
| 330 | return rcu_batches_completed_bh(); |
| 331 | } |
| 332 | |
| 333 | static void rcu_bh_torture_deferred_free(struct rcu_torture *p) |
| 334 | { |
| 335 | call_rcu_bh(&p->rtort_rcu, rcu_torture_cb); |
| 336 | } |
| 337 | |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 338 | struct rcu_bh_torture_synchronize { |
| 339 | struct rcu_head head; |
| 340 | struct completion completion; |
| 341 | }; |
| 342 | |
| 343 | static void rcu_bh_torture_wakeme_after_cb(struct rcu_head *head) |
| 344 | { |
| 345 | struct rcu_bh_torture_synchronize *rcu; |
| 346 | |
| 347 | rcu = container_of(head, struct rcu_bh_torture_synchronize, head); |
| 348 | complete(&rcu->completion); |
| 349 | } |
| 350 | |
| 351 | static void rcu_bh_torture_synchronize(void) |
| 352 | { |
| 353 | struct rcu_bh_torture_synchronize rcu; |
| 354 | |
| 355 | init_completion(&rcu.completion); |
| 356 | call_rcu_bh(&rcu.head, rcu_bh_torture_wakeme_after_cb); |
| 357 | wait_for_completion(&rcu.completion); |
| 358 | } |
| 359 | |
Paul E. McKenney | c32e066 | 2006-06-27 02:54:04 -0700 | [diff] [blame] | 360 | static struct rcu_torture_ops rcu_bh_ops = { |
| 361 | .init = NULL, |
| 362 | .cleanup = NULL, |
| 363 | .readlock = rcu_bh_torture_read_lock, |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 364 | .readdelay = rcu_read_delay, /* just reuse rcu's version. */ |
Paul E. McKenney | c32e066 | 2006-06-27 02:54:04 -0700 | [diff] [blame] | 365 | .readunlock = rcu_bh_torture_read_unlock, |
| 366 | .completed = rcu_bh_torture_completed, |
| 367 | .deferredfree = rcu_bh_torture_deferred_free, |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 368 | .sync = rcu_bh_torture_synchronize, |
Paul E. McKenney | c32e066 | 2006-06-27 02:54:04 -0700 | [diff] [blame] | 369 | .stats = NULL, |
| 370 | .name = "rcu_bh" |
| 371 | }; |
| 372 | |
Josh Triplett | 11a1470 | 2006-10-04 02:17:16 -0700 | [diff] [blame] | 373 | static struct rcu_torture_ops rcu_bh_sync_ops = { |
| 374 | .init = rcu_sync_torture_init, |
| 375 | .cleanup = NULL, |
| 376 | .readlock = rcu_bh_torture_read_lock, |
| 377 | .readdelay = rcu_read_delay, /* just reuse rcu's version. */ |
| 378 | .readunlock = rcu_bh_torture_read_unlock, |
| 379 | .completed = rcu_bh_torture_completed, |
| 380 | .deferredfree = rcu_sync_torture_deferred_free, |
| 381 | .sync = rcu_bh_torture_synchronize, |
| 382 | .stats = NULL, |
| 383 | .name = "rcu_bh_sync" |
| 384 | }; |
| 385 | |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 386 | /* |
| 387 | * Definitions for srcu torture testing. |
| 388 | */ |
| 389 | |
| 390 | static struct srcu_struct srcu_ctl; |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 391 | |
| 392 | static void srcu_torture_init(void) |
| 393 | { |
| 394 | init_srcu_struct(&srcu_ctl); |
Josh Triplett | e303373 | 2006-10-04 02:17:14 -0700 | [diff] [blame] | 395 | rcu_sync_torture_init(); |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 396 | } |
| 397 | |
| 398 | static void srcu_torture_cleanup(void) |
| 399 | { |
| 400 | synchronize_srcu(&srcu_ctl); |
| 401 | cleanup_srcu_struct(&srcu_ctl); |
| 402 | } |
| 403 | |
Josh Triplett | 012d3ca | 2006-12-06 20:40:19 -0800 | [diff] [blame] | 404 | static int srcu_torture_read_lock(void) __acquires(&srcu_ctl) |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 405 | { |
| 406 | return srcu_read_lock(&srcu_ctl); |
| 407 | } |
| 408 | |
| 409 | static void srcu_read_delay(struct rcu_random_state *rrsp) |
| 410 | { |
| 411 | long delay; |
| 412 | const long uspertick = 1000000 / HZ; |
| 413 | const long longdelay = 10; |
| 414 | |
| 415 | /* We want there to be long-running readers, but not all the time. */ |
| 416 | |
| 417 | delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick); |
| 418 | if (!delay) |
| 419 | schedule_timeout_interruptible(longdelay); |
| 420 | } |
| 421 | |
Josh Triplett | 012d3ca | 2006-12-06 20:40:19 -0800 | [diff] [blame] | 422 | static void srcu_torture_read_unlock(int idx) __releases(&srcu_ctl) |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 423 | { |
| 424 | srcu_read_unlock(&srcu_ctl, idx); |
| 425 | } |
| 426 | |
| 427 | static int srcu_torture_completed(void) |
| 428 | { |
| 429 | return srcu_batches_completed(&srcu_ctl); |
| 430 | } |
| 431 | |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 432 | static void srcu_torture_synchronize(void) |
| 433 | { |
| 434 | synchronize_srcu(&srcu_ctl); |
| 435 | } |
| 436 | |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 437 | static int srcu_torture_stats(char *page) |
| 438 | { |
| 439 | int cnt = 0; |
| 440 | int cpu; |
| 441 | int idx = srcu_ctl.completed & 0x1; |
| 442 | |
| 443 | cnt += sprintf(&page[cnt], "%s%s per-CPU(idx=%d):", |
| 444 | torture_type, TORTURE_FLAG, idx); |
| 445 | for_each_possible_cpu(cpu) { |
| 446 | cnt += sprintf(&page[cnt], " %d(%d,%d)", cpu, |
| 447 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], |
| 448 | per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); |
| 449 | } |
| 450 | cnt += sprintf(&page[cnt], "\n"); |
| 451 | return cnt; |
| 452 | } |
| 453 | |
| 454 | static struct rcu_torture_ops srcu_ops = { |
| 455 | .init = srcu_torture_init, |
| 456 | .cleanup = srcu_torture_cleanup, |
| 457 | .readlock = srcu_torture_read_lock, |
| 458 | .readdelay = srcu_read_delay, |
| 459 | .readunlock = srcu_torture_read_unlock, |
| 460 | .completed = srcu_torture_completed, |
Josh Triplett | e303373 | 2006-10-04 02:17:14 -0700 | [diff] [blame] | 461 | .deferredfree = rcu_sync_torture_deferred_free, |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 462 | .sync = srcu_torture_synchronize, |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 463 | .stats = srcu_torture_stats, |
| 464 | .name = "srcu" |
| 465 | }; |
| 466 | |
Josh Triplett | 4b6c2cc | 2006-10-04 02:17:16 -0700 | [diff] [blame] | 467 | /* |
| 468 | * Definitions for sched torture testing. |
| 469 | */ |
| 470 | |
| 471 | static int sched_torture_read_lock(void) |
| 472 | { |
| 473 | preempt_disable(); |
| 474 | return 0; |
| 475 | } |
| 476 | |
| 477 | static void sched_torture_read_unlock(int idx) |
| 478 | { |
| 479 | preempt_enable(); |
| 480 | } |
| 481 | |
| 482 | static int sched_torture_completed(void) |
| 483 | { |
| 484 | return 0; |
| 485 | } |
| 486 | |
| 487 | static void sched_torture_synchronize(void) |
| 488 | { |
| 489 | synchronize_sched(); |
| 490 | } |
| 491 | |
| 492 | static struct rcu_torture_ops sched_ops = { |
| 493 | .init = rcu_sync_torture_init, |
| 494 | .cleanup = NULL, |
| 495 | .readlock = sched_torture_read_lock, |
| 496 | .readdelay = rcu_read_delay, /* just reuse rcu's version. */ |
| 497 | .readunlock = sched_torture_read_unlock, |
| 498 | .completed = sched_torture_completed, |
| 499 | .deferredfree = rcu_sync_torture_deferred_free, |
| 500 | .sync = sched_torture_synchronize, |
| 501 | .stats = NULL, |
| 502 | .name = "sched" |
| 503 | }; |
| 504 | |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 505 | /* |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 506 | * RCU torture writer kthread. Repeatedly substitutes a new structure |
| 507 | * for that pointed to by rcu_torture_current, freeing the old structure |
| 508 | * after a series of grace periods (the "pipeline"). |
| 509 | */ |
| 510 | static int |
| 511 | rcu_torture_writer(void *arg) |
| 512 | { |
| 513 | int i; |
| 514 | long oldbatch = rcu_batches_completed(); |
| 515 | struct rcu_torture *rp; |
| 516 | struct rcu_torture *old_rp; |
| 517 | static DEFINE_RCU_RANDOM(rand); |
| 518 | |
| 519 | VERBOSE_PRINTK_STRING("rcu_torture_writer task started"); |
Ingo Molnar | dbdf65b | 2005-11-13 16:07:22 -0800 | [diff] [blame] | 520 | set_user_nice(current, 19); |
Ingo Molnar | e4e6bdb | 2006-12-29 16:47:14 -0800 | [diff] [blame] | 521 | current->flags |= PF_NOFREEZE; |
Ingo Molnar | dbdf65b | 2005-11-13 16:07:22 -0800 | [diff] [blame] | 522 | |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 523 | do { |
| 524 | schedule_timeout_uninterruptible(1); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 525 | if ((rp = rcu_torture_alloc()) == NULL) |
| 526 | continue; |
| 527 | rp->rtort_pipe_count = 0; |
| 528 | udelay(rcu_random(&rand) & 0x3ff); |
| 529 | old_rp = rcu_torture_current; |
Paul E. McKenney | 996417d | 2005-11-18 01:10:50 -0800 | [diff] [blame] | 530 | rp->rtort_mbtest = 1; |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 531 | rcu_assign_pointer(rcu_torture_current, rp); |
| 532 | smp_wmb(); |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 533 | if (old_rp) { |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 534 | i = old_rp->rtort_pipe_count; |
| 535 | if (i > RCU_TORTURE_PIPE_LEN) |
| 536 | i = RCU_TORTURE_PIPE_LEN; |
| 537 | atomic_inc(&rcu_torture_wcount[i]); |
| 538 | old_rp->rtort_pipe_count++; |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 539 | cur_ops->deferredfree(old_rp); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 540 | } |
| 541 | rcu_torture_current_version++; |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 542 | oldbatch = cur_ops->completed(); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 543 | } while (!kthread_should_stop() && !fullstop); |
| 544 | VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping"); |
| 545 | while (!kthread_should_stop()) |
| 546 | schedule_timeout_uninterruptible(1); |
| 547 | return 0; |
| 548 | } |
| 549 | |
| 550 | /* |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 551 | * RCU torture fake writer kthread. Repeatedly calls sync, with a random |
| 552 | * delay between calls. |
| 553 | */ |
| 554 | static int |
| 555 | rcu_torture_fakewriter(void *arg) |
| 556 | { |
| 557 | DEFINE_RCU_RANDOM(rand); |
| 558 | |
| 559 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started"); |
| 560 | set_user_nice(current, 19); |
Ingo Molnar | e4e6bdb | 2006-12-29 16:47:14 -0800 | [diff] [blame] | 561 | current->flags |= PF_NOFREEZE; |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 562 | |
| 563 | do { |
| 564 | schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); |
| 565 | udelay(rcu_random(&rand) & 0x3ff); |
| 566 | cur_ops->sync(); |
| 567 | } while (!kthread_should_stop() && !fullstop); |
| 568 | |
| 569 | VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping"); |
| 570 | while (!kthread_should_stop()) |
| 571 | schedule_timeout_uninterruptible(1); |
| 572 | return 0; |
| 573 | } |
| 574 | |
| 575 | /* |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 576 | * RCU torture reader kthread. Repeatedly dereferences rcu_torture_current, |
| 577 | * incrementing the corresponding element of the pipeline array. The |
| 578 | * counter in the element should never be greater than 1, otherwise, the |
| 579 | * RCU implementation is broken. |
| 580 | */ |
| 581 | static int |
| 582 | rcu_torture_reader(void *arg) |
| 583 | { |
| 584 | int completed; |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 585 | int idx; |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 586 | DEFINE_RCU_RANDOM(rand); |
| 587 | struct rcu_torture *p; |
| 588 | int pipe_count; |
| 589 | |
| 590 | VERBOSE_PRINTK_STRING("rcu_torture_reader task started"); |
Ingo Molnar | dbdf65b | 2005-11-13 16:07:22 -0800 | [diff] [blame] | 591 | set_user_nice(current, 19); |
Ingo Molnar | e4e6bdb | 2006-12-29 16:47:14 -0800 | [diff] [blame] | 592 | current->flags |= PF_NOFREEZE; |
Ingo Molnar | dbdf65b | 2005-11-13 16:07:22 -0800 | [diff] [blame] | 593 | |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 594 | do { |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 595 | idx = cur_ops->readlock(); |
| 596 | completed = cur_ops->completed(); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 597 | p = rcu_dereference(rcu_torture_current); |
| 598 | if (p == NULL) { |
| 599 | /* Wait for rcu_torture_writer to get underway */ |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 600 | cur_ops->readunlock(idx); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 601 | schedule_timeout_interruptible(HZ); |
| 602 | continue; |
| 603 | } |
Paul E. McKenney | 996417d | 2005-11-18 01:10:50 -0800 | [diff] [blame] | 604 | if (p->rtort_mbtest == 0) |
| 605 | atomic_inc(&n_rcu_torture_mberror); |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 606 | cur_ops->readdelay(&rand); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 607 | preempt_disable(); |
| 608 | pipe_count = p->rtort_pipe_count; |
| 609 | if (pipe_count > RCU_TORTURE_PIPE_LEN) { |
| 610 | /* Should not happen, but... */ |
| 611 | pipe_count = RCU_TORTURE_PIPE_LEN; |
| 612 | } |
| 613 | ++__get_cpu_var(rcu_torture_count)[pipe_count]; |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 614 | completed = cur_ops->completed() - completed; |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 615 | if (completed > RCU_TORTURE_PIPE_LEN) { |
| 616 | /* Should not happen, but... */ |
| 617 | completed = RCU_TORTURE_PIPE_LEN; |
| 618 | } |
| 619 | ++__get_cpu_var(rcu_torture_batch)[completed]; |
| 620 | preempt_enable(); |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 621 | cur_ops->readunlock(idx); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 622 | schedule(); |
| 623 | } while (!kthread_should_stop() && !fullstop); |
| 624 | VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping"); |
| 625 | while (!kthread_should_stop()) |
| 626 | schedule_timeout_uninterruptible(1); |
| 627 | return 0; |
| 628 | } |
| 629 | |
| 630 | /* |
| 631 | * Create an RCU-torture statistics message in the specified buffer. |
| 632 | */ |
| 633 | static int |
| 634 | rcu_torture_printk(char *page) |
| 635 | { |
| 636 | int cnt = 0; |
| 637 | int cpu; |
| 638 | int i; |
| 639 | long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; |
| 640 | long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; |
| 641 | |
KAMEZAWA Hiroyuki | 0a94502 | 2006-03-28 01:56:37 -0800 | [diff] [blame] | 642 | for_each_possible_cpu(cpu) { |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 643 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
| 644 | pipesummary[i] += per_cpu(rcu_torture_count, cpu)[i]; |
| 645 | batchsummary[i] += per_cpu(rcu_torture_batch, cpu)[i]; |
| 646 | } |
| 647 | } |
| 648 | for (i = RCU_TORTURE_PIPE_LEN - 1; i >= 0; i--) { |
| 649 | if (pipesummary[i] != 0) |
| 650 | break; |
| 651 | } |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 652 | cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 653 | cnt += sprintf(&page[cnt], |
Paul E. McKenney | 996417d | 2005-11-18 01:10:50 -0800 | [diff] [blame] | 654 | "rtc: %p ver: %ld tfle: %d rta: %d rtaf: %d rtf: %d " |
| 655 | "rtmbe: %d", |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 656 | rcu_torture_current, |
| 657 | rcu_torture_current_version, |
| 658 | list_empty(&rcu_torture_freelist), |
| 659 | atomic_read(&n_rcu_torture_alloc), |
| 660 | atomic_read(&n_rcu_torture_alloc_fail), |
Paul E. McKenney | 996417d | 2005-11-18 01:10:50 -0800 | [diff] [blame] | 661 | atomic_read(&n_rcu_torture_free), |
| 662 | atomic_read(&n_rcu_torture_mberror)); |
| 663 | if (atomic_read(&n_rcu_torture_mberror) != 0) |
| 664 | cnt += sprintf(&page[cnt], " !!!"); |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 665 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
Paul E. McKenney | 996417d | 2005-11-18 01:10:50 -0800 | [diff] [blame] | 666 | if (i > 1) { |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 667 | cnt += sprintf(&page[cnt], "!!! "); |
Paul E. McKenney | 996417d | 2005-11-18 01:10:50 -0800 | [diff] [blame] | 668 | atomic_inc(&n_rcu_torture_error); |
| 669 | } |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 670 | cnt += sprintf(&page[cnt], "Reader Pipe: "); |
| 671 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
| 672 | cnt += sprintf(&page[cnt], " %ld", pipesummary[i]); |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 673 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 674 | cnt += sprintf(&page[cnt], "Reader Batch: "); |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 675 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 676 | cnt += sprintf(&page[cnt], " %ld", batchsummary[i]); |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 677 | cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 678 | cnt += sprintf(&page[cnt], "Free-Block Circulation: "); |
| 679 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
| 680 | cnt += sprintf(&page[cnt], " %d", |
| 681 | atomic_read(&rcu_torture_wcount[i])); |
| 682 | } |
| 683 | cnt += sprintf(&page[cnt], "\n"); |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 684 | if (cur_ops->stats) |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 685 | cnt += cur_ops->stats(&page[cnt]); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 686 | return cnt; |
| 687 | } |
| 688 | |
| 689 | /* |
| 690 | * Print torture statistics. Caller must ensure that there is only |
| 691 | * one call to this function at a given time!!! This is normally |
| 692 | * accomplished by relying on the module system to only have one copy |
| 693 | * of the module loaded, and then by giving the rcu_torture_stats |
| 694 | * kthread full control (or the init/cleanup functions when rcu_torture_stats |
| 695 | * thread is not running). |
| 696 | */ |
| 697 | static void |
| 698 | rcu_torture_stats_print(void) |
| 699 | { |
| 700 | int cnt; |
| 701 | |
| 702 | cnt = rcu_torture_printk(printk_buf); |
| 703 | printk(KERN_ALERT "%s", printk_buf); |
| 704 | } |
| 705 | |
| 706 | /* |
| 707 | * Periodically prints torture statistics, if periodic statistics printing |
| 708 | * was specified via the stat_interval module parameter. |
| 709 | * |
| 710 | * No need to worry about fullstop here, since this one doesn't reference |
| 711 | * volatile state or register callbacks. |
| 712 | */ |
| 713 | static int |
| 714 | rcu_torture_stats(void *arg) |
| 715 | { |
| 716 | VERBOSE_PRINTK_STRING("rcu_torture_stats task started"); |
| 717 | do { |
| 718 | schedule_timeout_interruptible(stat_interval * HZ); |
| 719 | rcu_torture_stats_print(); |
| 720 | } while (!kthread_should_stop()); |
| 721 | VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping"); |
| 722 | return 0; |
| 723 | } |
| 724 | |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 725 | static int rcu_idle_cpu; /* Force all torture tasks off this CPU */ |
| 726 | |
| 727 | /* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case |
| 728 | * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs. |
| 729 | */ |
Paul E. McKenney | b2896d2 | 2006-10-04 02:17:03 -0700 | [diff] [blame] | 730 | static void rcu_torture_shuffle_tasks(void) |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 731 | { |
| 732 | cpumask_t tmp_mask = CPU_MASK_ALL; |
| 733 | int i; |
| 734 | |
| 735 | lock_cpu_hotplug(); |
| 736 | |
| 737 | /* No point in shuffling if there is only one online CPU (ex: UP) */ |
| 738 | if (num_online_cpus() == 1) { |
| 739 | unlock_cpu_hotplug(); |
| 740 | return; |
| 741 | } |
| 742 | |
| 743 | if (rcu_idle_cpu != -1) |
| 744 | cpu_clear(rcu_idle_cpu, tmp_mask); |
| 745 | |
| 746 | set_cpus_allowed(current, tmp_mask); |
| 747 | |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 748 | if (reader_tasks) { |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 749 | for (i = 0; i < nrealreaders; i++) |
| 750 | if (reader_tasks[i]) |
| 751 | set_cpus_allowed(reader_tasks[i], tmp_mask); |
| 752 | } |
| 753 | |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 754 | if (fakewriter_tasks) { |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 755 | for (i = 0; i < nfakewriters; i++) |
| 756 | if (fakewriter_tasks[i]) |
| 757 | set_cpus_allowed(fakewriter_tasks[i], tmp_mask); |
| 758 | } |
| 759 | |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 760 | if (writer_task) |
| 761 | set_cpus_allowed(writer_task, tmp_mask); |
| 762 | |
| 763 | if (stats_task) |
| 764 | set_cpus_allowed(stats_task, tmp_mask); |
| 765 | |
| 766 | if (rcu_idle_cpu == -1) |
| 767 | rcu_idle_cpu = num_online_cpus() - 1; |
| 768 | else |
| 769 | rcu_idle_cpu--; |
| 770 | |
| 771 | unlock_cpu_hotplug(); |
| 772 | } |
| 773 | |
| 774 | /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the |
| 775 | * system to become idle at a time and cut off its timer ticks. This is meant |
| 776 | * to test the support for such tickless idle CPU in RCU. |
| 777 | */ |
| 778 | static int |
| 779 | rcu_torture_shuffle(void *arg) |
| 780 | { |
| 781 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started"); |
| 782 | do { |
| 783 | schedule_timeout_interruptible(shuffle_interval * HZ); |
| 784 | rcu_torture_shuffle_tasks(); |
| 785 | } while (!kthread_should_stop()); |
| 786 | VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping"); |
| 787 | return 0; |
| 788 | } |
| 789 | |
Paul E. McKenney | 95c3832 | 2006-03-24 03:15:58 -0800 | [diff] [blame] | 790 | static inline void |
| 791 | rcu_torture_print_module_parms(char *tag) |
| 792 | { |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 793 | printk(KERN_ALERT "%s" TORTURE_FLAG |
| 794 | "--- %s: nreaders=%d nfakewriters=%d " |
Paul E. McKenney | 95c3832 | 2006-03-24 03:15:58 -0800 | [diff] [blame] | 795 | "stat_interval=%d verbose=%d test_no_idle_hz=%d " |
| 796 | "shuffle_interval = %d\n", |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 797 | torture_type, tag, nrealreaders, nfakewriters, |
| 798 | stat_interval, verbose, test_no_idle_hz, shuffle_interval); |
Paul E. McKenney | 95c3832 | 2006-03-24 03:15:58 -0800 | [diff] [blame] | 799 | } |
| 800 | |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 801 | static void |
| 802 | rcu_torture_cleanup(void) |
| 803 | { |
| 804 | int i; |
| 805 | |
| 806 | fullstop = 1; |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 807 | if (shuffler_task) { |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 808 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task"); |
| 809 | kthread_stop(shuffler_task); |
| 810 | } |
| 811 | shuffler_task = NULL; |
| 812 | |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 813 | if (writer_task) { |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 814 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task"); |
| 815 | kthread_stop(writer_task); |
| 816 | } |
| 817 | writer_task = NULL; |
| 818 | |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 819 | if (reader_tasks) { |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 820 | for (i = 0; i < nrealreaders; i++) { |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 821 | if (reader_tasks[i]) { |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 822 | VERBOSE_PRINTK_STRING( |
| 823 | "Stopping rcu_torture_reader task"); |
| 824 | kthread_stop(reader_tasks[i]); |
| 825 | } |
| 826 | reader_tasks[i] = NULL; |
| 827 | } |
| 828 | kfree(reader_tasks); |
| 829 | reader_tasks = NULL; |
| 830 | } |
| 831 | rcu_torture_current = NULL; |
| 832 | |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 833 | if (fakewriter_tasks) { |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 834 | for (i = 0; i < nfakewriters; i++) { |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 835 | if (fakewriter_tasks[i]) { |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 836 | VERBOSE_PRINTK_STRING( |
| 837 | "Stopping rcu_torture_fakewriter task"); |
| 838 | kthread_stop(fakewriter_tasks[i]); |
| 839 | } |
| 840 | fakewriter_tasks[i] = NULL; |
| 841 | } |
| 842 | kfree(fakewriter_tasks); |
| 843 | fakewriter_tasks = NULL; |
| 844 | } |
| 845 | |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 846 | if (stats_task) { |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 847 | VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task"); |
| 848 | kthread_stop(stats_task); |
| 849 | } |
| 850 | stats_task = NULL; |
| 851 | |
| 852 | /* Wait for all RCU callbacks to fire. */ |
Srivatsa Vaddagiri | 89d46b8 | 2005-12-12 00:37:06 -0800 | [diff] [blame] | 853 | rcu_barrier(); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 854 | |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 855 | rcu_torture_stats_print(); /* -After- the stats thread is stopped! */ |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 856 | |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 857 | if (cur_ops->cleanup) |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 858 | cur_ops->cleanup(); |
Paul E. McKenney | 95c3832 | 2006-03-24 03:15:58 -0800 | [diff] [blame] | 859 | if (atomic_read(&n_rcu_torture_error)) |
| 860 | rcu_torture_print_module_parms("End of test: FAILURE"); |
| 861 | else |
| 862 | rcu_torture_print_module_parms("End of test: SUCCESS"); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 863 | } |
| 864 | |
Josh Triplett | 6f8bc50 | 2007-05-08 00:25:24 -0700 | [diff] [blame] | 865 | static int __init |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 866 | rcu_torture_init(void) |
| 867 | { |
| 868 | int i; |
| 869 | int cpu; |
| 870 | int firsterr = 0; |
Josh Triplett | ade5fb8 | 2007-05-08 00:33:22 -0700 | [diff] [blame] | 871 | static struct rcu_torture_ops *torture_ops[] = |
| 872 | { &rcu_ops, &rcu_sync_ops, &rcu_bh_ops, &rcu_bh_sync_ops, |
| 873 | &srcu_ops, &sched_ops, }; |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 874 | |
| 875 | /* Process args and tell the world that the torturer is on the job. */ |
Josh Triplett | ade5fb8 | 2007-05-08 00:33:22 -0700 | [diff] [blame] | 876 | for (i = 0; i < ARRAY_SIZE(torture_ops); i++) { |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 877 | cur_ops = torture_ops[i]; |
Josh Triplett | ade5fb8 | 2007-05-08 00:33:22 -0700 | [diff] [blame] | 878 | if (strcmp(torture_type, cur_ops->name) == 0) |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 879 | break; |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 880 | } |
Josh Triplett | ade5fb8 | 2007-05-08 00:33:22 -0700 | [diff] [blame] | 881 | if (i == ARRAY_SIZE(torture_ops)) { |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 882 | printk(KERN_ALERT "rcutorture: invalid torture type: \"%s\"\n", |
| 883 | torture_type); |
| 884 | return (-EINVAL); |
| 885 | } |
Josh Triplett | c8e5b16 | 2007-05-08 00:33:20 -0700 | [diff] [blame] | 886 | if (cur_ops->init) |
Paul E. McKenney | 72e9bb5 | 2006-06-27 02:54:03 -0700 | [diff] [blame] | 887 | cur_ops->init(); /* no "goto unwind" prior to this point!!! */ |
| 888 | |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 889 | if (nreaders >= 0) |
| 890 | nrealreaders = nreaders; |
| 891 | else |
| 892 | nrealreaders = 2 * num_online_cpus(); |
Paul E. McKenney | 95c3832 | 2006-03-24 03:15:58 -0800 | [diff] [blame] | 893 | rcu_torture_print_module_parms("Start of test"); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 894 | fullstop = 0; |
| 895 | |
| 896 | /* Set up the freelist. */ |
| 897 | |
| 898 | INIT_LIST_HEAD(&rcu_torture_freelist); |
Ahmed S. Darwish | 788e770 | 2007-05-08 00:33:14 -0700 | [diff] [blame] | 899 | for (i = 0; i < ARRAY_SIZE(rcu_tortures); i++) { |
Paul E. McKenney | 996417d | 2005-11-18 01:10:50 -0800 | [diff] [blame] | 900 | rcu_tortures[i].rtort_mbtest = 0; |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 901 | list_add_tail(&rcu_tortures[i].rtort_free, |
| 902 | &rcu_torture_freelist); |
| 903 | } |
| 904 | |
| 905 | /* Initialize the statistics so that each run gets its own numbers. */ |
| 906 | |
| 907 | rcu_torture_current = NULL; |
| 908 | rcu_torture_current_version = 0; |
| 909 | atomic_set(&n_rcu_torture_alloc, 0); |
| 910 | atomic_set(&n_rcu_torture_alloc_fail, 0); |
| 911 | atomic_set(&n_rcu_torture_free, 0); |
Paul E. McKenney | 996417d | 2005-11-18 01:10:50 -0800 | [diff] [blame] | 912 | atomic_set(&n_rcu_torture_mberror, 0); |
| 913 | atomic_set(&n_rcu_torture_error, 0); |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 914 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) |
| 915 | atomic_set(&rcu_torture_wcount[i], 0); |
KAMEZAWA Hiroyuki | 0a94502 | 2006-03-28 01:56:37 -0800 | [diff] [blame] | 916 | for_each_possible_cpu(cpu) { |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 917 | for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { |
| 918 | per_cpu(rcu_torture_count, cpu)[i] = 0; |
| 919 | per_cpu(rcu_torture_batch, cpu)[i] = 0; |
| 920 | } |
| 921 | } |
| 922 | |
| 923 | /* Start up the kthreads. */ |
| 924 | |
| 925 | VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task"); |
| 926 | writer_task = kthread_run(rcu_torture_writer, NULL, |
| 927 | "rcu_torture_writer"); |
| 928 | if (IS_ERR(writer_task)) { |
| 929 | firsterr = PTR_ERR(writer_task); |
| 930 | VERBOSE_PRINTK_ERRSTRING("Failed to create writer"); |
| 931 | writer_task = NULL; |
| 932 | goto unwind; |
| 933 | } |
Josh Triplett | b772e1d | 2006-10-04 02:17:13 -0700 | [diff] [blame] | 934 | fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]), |
| 935 | GFP_KERNEL); |
| 936 | if (fakewriter_tasks == NULL) { |
| 937 | VERBOSE_PRINTK_ERRSTRING("out of memory"); |
| 938 | firsterr = -ENOMEM; |
| 939 | goto unwind; |
| 940 | } |
| 941 | for (i = 0; i < nfakewriters; i++) { |
| 942 | VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task"); |
| 943 | fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL, |
| 944 | "rcu_torture_fakewriter"); |
| 945 | if (IS_ERR(fakewriter_tasks[i])) { |
| 946 | firsterr = PTR_ERR(fakewriter_tasks[i]); |
| 947 | VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter"); |
| 948 | fakewriter_tasks[i] = NULL; |
| 949 | goto unwind; |
| 950 | } |
| 951 | } |
Josh Triplett | 2860aab | 2006-10-04 02:17:11 -0700 | [diff] [blame] | 952 | reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]), |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 953 | GFP_KERNEL); |
| 954 | if (reader_tasks == NULL) { |
| 955 | VERBOSE_PRINTK_ERRSTRING("out of memory"); |
| 956 | firsterr = -ENOMEM; |
| 957 | goto unwind; |
| 958 | } |
| 959 | for (i = 0; i < nrealreaders; i++) { |
| 960 | VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task"); |
| 961 | reader_tasks[i] = kthread_run(rcu_torture_reader, NULL, |
| 962 | "rcu_torture_reader"); |
| 963 | if (IS_ERR(reader_tasks[i])) { |
| 964 | firsterr = PTR_ERR(reader_tasks[i]); |
| 965 | VERBOSE_PRINTK_ERRSTRING("Failed to create reader"); |
| 966 | reader_tasks[i] = NULL; |
| 967 | goto unwind; |
| 968 | } |
| 969 | } |
| 970 | if (stat_interval > 0) { |
| 971 | VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task"); |
| 972 | stats_task = kthread_run(rcu_torture_stats, NULL, |
| 973 | "rcu_torture_stats"); |
| 974 | if (IS_ERR(stats_task)) { |
| 975 | firsterr = PTR_ERR(stats_task); |
| 976 | VERBOSE_PRINTK_ERRSTRING("Failed to create stats"); |
| 977 | stats_task = NULL; |
| 978 | goto unwind; |
| 979 | } |
| 980 | } |
Srivatsa Vaddagiri | d84f520 | 2006-01-08 01:03:42 -0800 | [diff] [blame] | 981 | if (test_no_idle_hz) { |
| 982 | rcu_idle_cpu = num_online_cpus() - 1; |
| 983 | /* Create the shuffler thread */ |
| 984 | shuffler_task = kthread_run(rcu_torture_shuffle, NULL, |
| 985 | "rcu_torture_shuffle"); |
| 986 | if (IS_ERR(shuffler_task)) { |
| 987 | firsterr = PTR_ERR(shuffler_task); |
| 988 | VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler"); |
| 989 | shuffler_task = NULL; |
| 990 | goto unwind; |
| 991 | } |
| 992 | } |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 993 | return 0; |
| 994 | |
| 995 | unwind: |
| 996 | rcu_torture_cleanup(); |
| 997 | return firsterr; |
| 998 | } |
| 999 | |
| 1000 | module_init(rcu_torture_init); |
| 1001 | module_exit(rcu_torture_cleanup); |