subr_lockdebug.c revision 1.4.2.2
1 1.4.2.2 yamt /* $NetBSD: subr_lockdebug.c,v 1.4.2.2 2007/02/26 09:11:14 yamt Exp $ */ 2 1.4.2.2 yamt 3 1.4.2.2 yamt /*- 4 1.4.2.2 yamt * Copyright (c) 2006, 2007 The NetBSD Foundation, Inc. 5 1.4.2.2 yamt * All rights reserved. 6 1.4.2.2 yamt * 7 1.4.2.2 yamt * This code is derived from software contributed to The NetBSD Foundation 8 1.4.2.2 yamt * by Andrew Doran. 9 1.4.2.2 yamt * 10 1.4.2.2 yamt * Redistribution and use in source and binary forms, with or without 11 1.4.2.2 yamt * modification, are permitted provided that the following conditions 12 1.4.2.2 yamt * are met: 13 1.4.2.2 yamt * 1. Redistributions of source code must retain the above copyright 14 1.4.2.2 yamt * notice, this list of conditions and the following disclaimer. 15 1.4.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright 16 1.4.2.2 yamt * notice, this list of conditions and the following disclaimer in the 17 1.4.2.2 yamt * documentation and/or other materials provided with the distribution. 18 1.4.2.2 yamt * 3. All advertising materials mentioning features or use of this software 19 1.4.2.2 yamt * must display the following acknowledgement: 20 1.4.2.2 yamt * This product includes software developed by the NetBSD 21 1.4.2.2 yamt * Foundation, Inc. and its contributors. 22 1.4.2.2 yamt * 4. Neither the name of The NetBSD Foundation nor the names of its 23 1.4.2.2 yamt * contributors may be used to endorse or promote products derived 24 1.4.2.2 yamt * from this software without specific prior written permission. 25 1.4.2.2 yamt * 26 1.4.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 1.4.2.2 yamt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 1.4.2.2 yamt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 1.4.2.2 yamt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 1.4.2.2 yamt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 1.4.2.2 yamt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 1.4.2.2 yamt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 1.4.2.2 yamt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 1.4.2.2 yamt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 1.4.2.2 yamt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 1.4.2.2 yamt * POSSIBILITY OF SUCH DAMAGE. 37 1.4.2.2 yamt */ 38 1.4.2.2 yamt 39 1.4.2.2 yamt /* 40 1.4.2.2 yamt * Basic lock debugging code shared among lock primatives. 41 1.4.2.2 yamt */ 42 1.4.2.2 yamt 43 1.4.2.2 yamt #include "opt_multiprocessor.h" 44 1.4.2.2 yamt #include "opt_ddb.h" 45 1.4.2.2 yamt 46 1.4.2.2 yamt #include <sys/cdefs.h> 47 1.4.2.2 yamt __KERNEL_RCSID(0, "$NetBSD: subr_lockdebug.c,v 1.4.2.2 2007/02/26 09:11:14 yamt Exp $"); 48 1.4.2.2 yamt 49 1.4.2.2 yamt #include <sys/param.h> 50 1.4.2.2 yamt #include <sys/proc.h> 51 1.4.2.2 yamt #include <sys/systm.h> 52 1.4.2.2 yamt #include <sys/kmem.h> 53 1.4.2.2 yamt #include <sys/lock.h> 54 1.4.2.2 yamt #include <sys/lockdebug.h> 55 1.4.2.2 yamt #include <sys/sleepq.h> 56 1.4.2.2 yamt 57 1.4.2.2 yamt #include <machine/cpu.h> 58 1.4.2.2 yamt 59 1.4.2.2 yamt #ifdef LOCKDEBUG 60 1.4.2.2 yamt 61 1.4.2.2 yamt #define LD_BATCH_SHIFT 9 62 1.4.2.2 yamt #define LD_BATCH (1 << LD_BATCH_SHIFT) 63 1.4.2.2 yamt #define LD_BATCH_MASK (LD_BATCH - 1) 64 1.4.2.2 yamt #define LD_MAX_LOCKS 1048576 65 1.4.2.2 yamt #define LD_SLOP 16 66 1.4.2.2 yamt 67 1.4.2.2 yamt #define LD_LOCKED 0x01 68 1.4.2.2 yamt #define LD_SLEEPER 0x02 69 1.4.2.2 yamt 70 1.4.2.2 yamt #define LD_NOID LD_MAX_LOCKS 71 1.4.2.2 yamt 72 1.4.2.2 yamt typedef union lockdebuglk { 73 1.4.2.2 yamt struct { 74 1.4.2.2 yamt __cpu_simple_lock_t lku_lock; 75 1.4.2.2 yamt int lku_oldspl; 76 1.4.2.2 yamt } ul; 77 1.4.2.2 yamt uint8_t lk_pad[64]; 78 1.4.2.2 yamt } volatile __aligned(64) lockdebuglk_t; 79 1.4.2.2 yamt 80 1.4.2.2 yamt #define lk_lock ul.lku_lock 81 1.4.2.2 yamt #define lk_oldspl ul.lku_oldspl 82 1.4.2.2 yamt 83 1.4.2.2 yamt typedef struct lockdebug { 84 1.4.2.2 yamt _TAILQ_ENTRY(struct lockdebug, volatile) ld_chain; 85 1.4.2.2 yamt _TAILQ_ENTRY(struct lockdebug, volatile) ld_achain; 86 1.4.2.2 yamt volatile void *ld_lock; 87 1.4.2.2 yamt lockops_t *ld_lockops; 88 1.4.2.2 yamt struct lwp *ld_lwp; 89 1.4.2.2 yamt uintptr_t ld_locked; 90 1.4.2.2 yamt uintptr_t ld_unlocked; 91 1.4.2.2 yamt u_int ld_id; 92 1.4.2.2 yamt uint16_t ld_shares; 93 1.4.2.2 yamt uint16_t ld_cpu; 94 1.4.2.2 yamt uint8_t ld_flags; 95 1.4.2.2 yamt uint8_t ld_shwant; /* advisory */ 96 1.4.2.2 yamt uint8_t ld_exwant; /* advisory */ 97 1.4.2.2 yamt uint8_t ld_unused; 98 1.4.2.2 yamt } volatile lockdebug_t; 99 1.4.2.2 yamt 100 1.4.2.2 yamt typedef _TAILQ_HEAD(lockdebuglist, struct lockdebug, volatile) lockdebuglist_t; 101 1.4.2.2 yamt 102 1.4.2.2 yamt lockdebuglk_t ld_sleeper_lk; 103 1.4.2.2 yamt lockdebuglk_t ld_spinner_lk; 104 1.4.2.2 yamt lockdebuglk_t ld_free_lk; 105 1.4.2.2 yamt 106 1.4.2.2 yamt lockdebuglist_t ld_sleepers; 107 1.4.2.2 yamt lockdebuglist_t ld_spinners; 108 1.4.2.2 yamt lockdebuglist_t ld_free; 109 1.4.2.2 yamt lockdebuglist_t ld_all; 110 1.4.2.2 yamt int ld_nfree; 111 1.4.2.2 yamt int ld_freeptr; 112 1.4.2.2 yamt int ld_recurse; 113 1.4.2.2 yamt lockdebug_t *ld_table[LD_MAX_LOCKS / LD_BATCH]; 114 1.4.2.2 yamt 115 1.4.2.2 yamt lockdebug_t ld_prime[LD_BATCH]; 116 1.4.2.2 yamt 117 1.4.2.2 yamt void lockdebug_abort1(lockdebug_t *, lockdebuglk_t *lk, const char *, 118 1.4.2.2 yamt const char *); 119 1.4.2.2 yamt void lockdebug_more(void); 120 1.4.2.2 yamt 121 1.4.2.2 yamt static inline void 122 1.4.2.2 yamt lockdebug_lock(lockdebuglk_t *lk) 123 1.4.2.2 yamt { 124 1.4.2.2 yamt int s; 125 1.4.2.2 yamt 126 1.4.2.2 yamt s = spllock(); 127 1.4.2.2 yamt __cpu_simple_lock(&lk->lk_lock); 128 1.4.2.2 yamt lk->lk_oldspl = s; 129 1.4.2.2 yamt } 130 1.4.2.2 yamt 131 1.4.2.2 yamt static inline void 132 1.4.2.2 yamt lockdebug_unlock(lockdebuglk_t *lk) 133 1.4.2.2 yamt { 134 1.4.2.2 yamt int s; 135 1.4.2.2 yamt 136 1.4.2.2 yamt s = lk->lk_oldspl; 137 1.4.2.2 yamt __cpu_simple_unlock(&(lk->lk_lock)); 138 1.4.2.2 yamt splx(s); 139 1.4.2.2 yamt } 140 1.4.2.2 yamt 141 1.4.2.2 yamt /* 142 1.4.2.2 yamt * lockdebug_lookup: 143 1.4.2.2 yamt * 144 1.4.2.2 yamt * Find a lockdebug structure by ID and return it locked. 145 1.4.2.2 yamt */ 146 1.4.2.2 yamt static inline lockdebug_t * 147 1.4.2.2 yamt lockdebug_lookup(u_int id, lockdebuglk_t **lk) 148 1.4.2.2 yamt { 149 1.4.2.2 yamt lockdebug_t *base, *ld; 150 1.4.2.2 yamt 151 1.4.2.2 yamt if (id == LD_NOID) 152 1.4.2.2 yamt return NULL; 153 1.4.2.2 yamt 154 1.4.2.2 yamt if (id == 0 || id >= LD_MAX_LOCKS) 155 1.4.2.2 yamt panic("lockdebug_lookup: uninitialized lock (1, id=%d)", id); 156 1.4.2.2 yamt 157 1.4.2.2 yamt base = ld_table[id >> LD_BATCH_SHIFT]; 158 1.4.2.2 yamt ld = base + (id & LD_BATCH_MASK); 159 1.4.2.2 yamt 160 1.4.2.2 yamt if (base == NULL || ld->ld_lock == NULL || ld->ld_id != id) 161 1.4.2.2 yamt panic("lockdebug_lookup: uninitialized lock (2, id=%d)", id); 162 1.4.2.2 yamt 163 1.4.2.2 yamt if ((ld->ld_flags & LD_SLEEPER) != 0) 164 1.4.2.2 yamt *lk = &ld_sleeper_lk; 165 1.4.2.2 yamt else 166 1.4.2.2 yamt *lk = &ld_spinner_lk; 167 1.4.2.2 yamt 168 1.4.2.2 yamt lockdebug_lock(*lk); 169 1.4.2.2 yamt return ld; 170 1.4.2.2 yamt } 171 1.4.2.2 yamt 172 1.4.2.2 yamt /* 173 1.4.2.2 yamt * lockdebug_init: 174 1.4.2.2 yamt * 175 1.4.2.2 yamt * Initialize the lockdebug system. Allocate an initial pool of 176 1.4.2.2 yamt * lockdebug structures before the VM system is up and running. 177 1.4.2.2 yamt */ 178 1.4.2.2 yamt void 179 1.4.2.2 yamt lockdebug_init(void) 180 1.4.2.2 yamt { 181 1.4.2.2 yamt lockdebug_t *ld; 182 1.4.2.2 yamt int i; 183 1.4.2.2 yamt 184 1.4.2.2 yamt __cpu_simple_lock_init(&ld_sleeper_lk.lk_lock); 185 1.4.2.2 yamt __cpu_simple_lock_init(&ld_spinner_lk.lk_lock); 186 1.4.2.2 yamt __cpu_simple_lock_init(&ld_free_lk.lk_lock); 187 1.4.2.2 yamt 188 1.4.2.2 yamt TAILQ_INIT(&ld_free); 189 1.4.2.2 yamt TAILQ_INIT(&ld_all); 190 1.4.2.2 yamt TAILQ_INIT(&ld_sleepers); 191 1.4.2.2 yamt TAILQ_INIT(&ld_spinners); 192 1.4.2.2 yamt 193 1.4.2.2 yamt ld = ld_prime; 194 1.4.2.2 yamt ld_table[0] = ld; 195 1.4.2.2 yamt for (i = 1, ld++; i < LD_BATCH; i++, ld++) { 196 1.4.2.2 yamt ld->ld_id = i; 197 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain); 198 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain); 199 1.4.2.2 yamt } 200 1.4.2.2 yamt ld_freeptr = 1; 201 1.4.2.2 yamt ld_nfree = LD_BATCH - 1; 202 1.4.2.2 yamt } 203 1.4.2.2 yamt 204 1.4.2.2 yamt /* 205 1.4.2.2 yamt * lockdebug_alloc: 206 1.4.2.2 yamt * 207 1.4.2.2 yamt * A lock is being initialized, so allocate an associated debug 208 1.4.2.2 yamt * structure. 209 1.4.2.2 yamt */ 210 1.4.2.2 yamt u_int 211 1.4.2.2 yamt lockdebug_alloc(volatile void *lock, lockops_t *lo) 212 1.4.2.2 yamt { 213 1.4.2.2 yamt struct cpu_info *ci; 214 1.4.2.2 yamt lockdebug_t *ld; 215 1.4.2.2 yamt 216 1.4.2.2 yamt if (ld_freeptr == 0) { 217 1.4.2.2 yamt printf("lockdebug_alloc: not initialized yet, lock=%p\n", 218 1.4.2.2 yamt __UNVOLATILE(lock)); 219 1.4.2.2 yamt return LD_NOID; 220 1.4.2.2 yamt } 221 1.4.2.2 yamt 222 1.4.2.2 yamt if (panicstr != NULL) 223 1.4.2.2 yamt return LD_NOID; 224 1.4.2.2 yamt 225 1.4.2.2 yamt ci = curcpu(); 226 1.4.2.2 yamt 227 1.4.2.2 yamt /* 228 1.4.2.2 yamt * Pinch a new debug structure. We may recurse because we call 229 1.4.2.2 yamt * kmem_alloc(), which may need to initialize new locks somewhere 230 1.4.2.2 yamt * down the path. If not recursing, we try to maintain at keep 231 1.4.2.2 yamt * LD_SLOP structures free, which should hopefully be enough to 232 1.4.2.2 yamt * satisfy kmem_alloc(). If we can't provide a structure, not to 233 1.4.2.2 yamt * worry: we'll just mark the lock as not having an ID. 234 1.4.2.2 yamt */ 235 1.4.2.2 yamt lockdebug_lock(&ld_free_lk); 236 1.4.2.2 yamt ci->ci_lkdebug_recurse++; 237 1.4.2.2 yamt 238 1.4.2.2 yamt if (TAILQ_EMPTY(&ld_free)) { 239 1.4.2.2 yamt if (ci->ci_lkdebug_recurse > 1) { 240 1.4.2.2 yamt ci->ci_lkdebug_recurse--; 241 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk); 242 1.4.2.2 yamt return LD_NOID; 243 1.4.2.2 yamt } 244 1.4.2.2 yamt lockdebug_more(); 245 1.4.2.2 yamt } else if (ci->ci_lkdebug_recurse == 1 && ld_nfree < LD_SLOP) 246 1.4.2.2 yamt lockdebug_more(); 247 1.4.2.2 yamt 248 1.4.2.2 yamt if ((ld = TAILQ_FIRST(&ld_free)) == NULL) { 249 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk); 250 1.4.2.2 yamt return LD_NOID; 251 1.4.2.2 yamt } 252 1.4.2.2 yamt 253 1.4.2.2 yamt TAILQ_REMOVE(&ld_free, ld, ld_chain); 254 1.4.2.2 yamt ld_nfree--; 255 1.4.2.2 yamt 256 1.4.2.2 yamt ci->ci_lkdebug_recurse--; 257 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk); 258 1.4.2.2 yamt 259 1.4.2.2 yamt if (ld->ld_lock != NULL) 260 1.4.2.2 yamt panic("lockdebug_alloc: corrupt table"); 261 1.4.2.2 yamt 262 1.4.2.2 yamt if (lo->lo_sleeplock) 263 1.4.2.2 yamt lockdebug_lock(&ld_sleeper_lk); 264 1.4.2.2 yamt else 265 1.4.2.2 yamt lockdebug_lock(&ld_spinner_lk); 266 1.4.2.2 yamt 267 1.4.2.2 yamt /* Initialise the structure. */ 268 1.4.2.2 yamt ld->ld_lock = lock; 269 1.4.2.2 yamt ld->ld_lockops = lo; 270 1.4.2.2 yamt ld->ld_locked = 0; 271 1.4.2.2 yamt ld->ld_unlocked = 0; 272 1.4.2.2 yamt ld->ld_lwp = NULL; 273 1.4.2.2 yamt 274 1.4.2.2 yamt if (lo->lo_sleeplock) { 275 1.4.2.2 yamt ld->ld_flags = LD_SLEEPER; 276 1.4.2.2 yamt lockdebug_unlock(&ld_sleeper_lk); 277 1.4.2.2 yamt } else { 278 1.4.2.2 yamt ld->ld_flags = 0; 279 1.4.2.2 yamt lockdebug_unlock(&ld_spinner_lk); 280 1.4.2.2 yamt } 281 1.4.2.2 yamt 282 1.4.2.2 yamt return ld->ld_id; 283 1.4.2.2 yamt } 284 1.4.2.2 yamt 285 1.4.2.2 yamt /* 286 1.4.2.2 yamt * lockdebug_free: 287 1.4.2.2 yamt * 288 1.4.2.2 yamt * A lock is being destroyed, so release debugging resources. 289 1.4.2.2 yamt */ 290 1.4.2.2 yamt void 291 1.4.2.2 yamt lockdebug_free(volatile void *lock, u_int id) 292 1.4.2.2 yamt { 293 1.4.2.2 yamt lockdebug_t *ld; 294 1.4.2.2 yamt lockdebuglk_t *lk; 295 1.4.2.2 yamt 296 1.4.2.2 yamt if (panicstr != NULL) 297 1.4.2.2 yamt return; 298 1.4.2.2 yamt 299 1.4.2.2 yamt if ((ld = lockdebug_lookup(id, &lk)) == NULL) 300 1.4.2.2 yamt return; 301 1.4.2.2 yamt 302 1.4.2.2 yamt if (ld->ld_lock != lock) { 303 1.4.2.2 yamt panic("lockdebug_free: destroying uninitialized lock %p" 304 1.4.2.2 yamt "(ld_id=%d ld_lock=%p)", lock, id, ld->ld_lock); 305 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__, "lock record follows"); 306 1.4.2.2 yamt } 307 1.4.2.2 yamt if ((ld->ld_flags & LD_LOCKED) != 0 || ld->ld_shares != 0) 308 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__, "is locked"); 309 1.4.2.2 yamt 310 1.4.2.2 yamt ld->ld_lock = NULL; 311 1.4.2.2 yamt 312 1.4.2.2 yamt lockdebug_unlock(lk); 313 1.4.2.2 yamt 314 1.4.2.2 yamt lockdebug_lock(&ld_free_lk); 315 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain); 316 1.4.2.2 yamt ld_nfree++; 317 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk); 318 1.4.2.2 yamt } 319 1.4.2.2 yamt 320 1.4.2.2 yamt /* 321 1.4.2.2 yamt * lockdebug_more: 322 1.4.2.2 yamt * 323 1.4.2.2 yamt * Allocate a batch of debug structures and add to the free list. 324 1.4.2.2 yamt * Must be called with ld_free_lk held. 325 1.4.2.2 yamt */ 326 1.4.2.2 yamt void 327 1.4.2.2 yamt lockdebug_more(void) 328 1.4.2.2 yamt { 329 1.4.2.2 yamt lockdebug_t *ld; 330 1.4.2.2 yamt void *block; 331 1.4.2.2 yamt int i, base; 332 1.4.2.2 yamt 333 1.4.2.2 yamt while (ld_nfree < LD_SLOP) { 334 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk); 335 1.4.2.2 yamt block = kmem_zalloc(LD_BATCH * sizeof(lockdebug_t), KM_SLEEP); 336 1.4.2.2 yamt lockdebug_lock(&ld_free_lk); 337 1.4.2.2 yamt 338 1.4.2.2 yamt if (block == NULL) 339 1.4.2.2 yamt return; 340 1.4.2.2 yamt 341 1.4.2.2 yamt if (ld_nfree > LD_SLOP) { 342 1.4.2.2 yamt /* Somebody beat us to it. */ 343 1.4.2.2 yamt lockdebug_unlock(&ld_free_lk); 344 1.4.2.2 yamt kmem_free(block, LD_BATCH * sizeof(lockdebug_t)); 345 1.4.2.2 yamt lockdebug_lock(&ld_free_lk); 346 1.4.2.2 yamt continue; 347 1.4.2.2 yamt } 348 1.4.2.2 yamt 349 1.4.2.2 yamt base = ld_freeptr; 350 1.4.2.2 yamt ld_nfree += LD_BATCH; 351 1.4.2.2 yamt ld = block; 352 1.4.2.2 yamt base <<= LD_BATCH_SHIFT; 353 1.4.2.2 yamt 354 1.4.2.2 yamt for (i = 0; i < LD_BATCH; i++, ld++) { 355 1.4.2.2 yamt ld->ld_id = i + base; 356 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_free, ld, ld_chain); 357 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_all, ld, ld_achain); 358 1.4.2.2 yamt } 359 1.4.2.2 yamt 360 1.4.2.2 yamt mb_write(); 361 1.4.2.2 yamt ld_table[ld_freeptr++] = block; 362 1.4.2.2 yamt } 363 1.4.2.2 yamt } 364 1.4.2.2 yamt 365 1.4.2.2 yamt /* 366 1.4.2.2 yamt * lockdebug_wantlock: 367 1.4.2.2 yamt * 368 1.4.2.2 yamt * Process the preamble to a lock acquire. 369 1.4.2.2 yamt */ 370 1.4.2.2 yamt void 371 1.4.2.2 yamt lockdebug_wantlock(u_int id, uintptr_t where, int shared) 372 1.4.2.2 yamt { 373 1.4.2.2 yamt struct lwp *l = curlwp; 374 1.4.2.2 yamt lockdebuglk_t *lk; 375 1.4.2.2 yamt lockdebug_t *ld; 376 1.4.2.2 yamt bool recurse; 377 1.4.2.2 yamt 378 1.4.2.2 yamt (void)shared; 379 1.4.2.2 yamt recurse = false; 380 1.4.2.2 yamt 381 1.4.2.2 yamt if (panicstr != NULL) 382 1.4.2.2 yamt return; 383 1.4.2.2 yamt 384 1.4.2.2 yamt if ((ld = lockdebug_lookup(id, &lk)) == NULL) 385 1.4.2.2 yamt return; 386 1.4.2.2 yamt 387 1.4.2.2 yamt if ((ld->ld_flags & LD_LOCKED) != 0) { 388 1.4.2.2 yamt if ((ld->ld_flags & LD_SLEEPER) != 0) { 389 1.4.2.2 yamt if (ld->ld_lwp == l) 390 1.4.2.2 yamt recurse = true; 391 1.4.2.2 yamt } else if (ld->ld_cpu == (uint16_t)cpu_number()) 392 1.4.2.2 yamt recurse = true; 393 1.4.2.2 yamt } 394 1.4.2.2 yamt 395 1.4.2.2 yamt if (shared) 396 1.4.2.2 yamt ld->ld_shwant++; 397 1.4.2.2 yamt else 398 1.4.2.2 yamt ld->ld_exwant++; 399 1.4.2.2 yamt 400 1.4.2.2 yamt if (recurse) 401 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__, "locking against myself"); 402 1.4.2.2 yamt 403 1.4.2.2 yamt lockdebug_unlock(lk); 404 1.4.2.2 yamt } 405 1.4.2.2 yamt 406 1.4.2.2 yamt /* 407 1.4.2.2 yamt * lockdebug_locked: 408 1.4.2.2 yamt * 409 1.4.2.2 yamt * Process a lock acquire operation. 410 1.4.2.2 yamt */ 411 1.4.2.2 yamt void 412 1.4.2.2 yamt lockdebug_locked(u_int id, uintptr_t where, int shared) 413 1.4.2.2 yamt { 414 1.4.2.2 yamt struct lwp *l = curlwp; 415 1.4.2.2 yamt lockdebuglk_t *lk; 416 1.4.2.2 yamt lockdebug_t *ld; 417 1.4.2.2 yamt 418 1.4.2.2 yamt if (panicstr != NULL) 419 1.4.2.2 yamt return; 420 1.4.2.2 yamt 421 1.4.2.2 yamt if ((ld = lockdebug_lookup(id, &lk)) == NULL) 422 1.4.2.2 yamt return; 423 1.4.2.2 yamt 424 1.4.2.2 yamt if (shared) { 425 1.4.2.2 yamt l->l_shlocks++; 426 1.4.2.2 yamt ld->ld_shares++; 427 1.4.2.2 yamt ld->ld_shwant--; 428 1.4.2.2 yamt } else { 429 1.4.2.2 yamt if ((ld->ld_flags & LD_LOCKED) != 0) 430 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__, 431 1.4.2.2 yamt "already locked"); 432 1.4.2.2 yamt 433 1.4.2.2 yamt ld->ld_flags |= LD_LOCKED; 434 1.4.2.2 yamt ld->ld_locked = where; 435 1.4.2.2 yamt ld->ld_cpu = (uint16_t)cpu_number(); 436 1.4.2.2 yamt ld->ld_lwp = l; 437 1.4.2.2 yamt ld->ld_exwant--; 438 1.4.2.2 yamt 439 1.4.2.2 yamt if ((ld->ld_flags & LD_SLEEPER) != 0) { 440 1.4.2.2 yamt l->l_exlocks++; 441 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_sleepers, ld, ld_chain); 442 1.4.2.2 yamt } else { 443 1.4.2.2 yamt curcpu()->ci_spin_locks2++; 444 1.4.2.2 yamt TAILQ_INSERT_TAIL(&ld_spinners, ld, ld_chain); 445 1.4.2.2 yamt } 446 1.4.2.2 yamt } 447 1.4.2.2 yamt 448 1.4.2.2 yamt lockdebug_unlock(lk); 449 1.4.2.2 yamt } 450 1.4.2.2 yamt 451 1.4.2.2 yamt /* 452 1.4.2.2 yamt * lockdebug_unlocked: 453 1.4.2.2 yamt * 454 1.4.2.2 yamt * Process a lock release operation. 455 1.4.2.2 yamt */ 456 1.4.2.2 yamt void 457 1.4.2.2 yamt lockdebug_unlocked(u_int id, uintptr_t where, int shared) 458 1.4.2.2 yamt { 459 1.4.2.2 yamt struct lwp *l = curlwp; 460 1.4.2.2 yamt lockdebuglk_t *lk; 461 1.4.2.2 yamt lockdebug_t *ld; 462 1.4.2.2 yamt 463 1.4.2.2 yamt if (panicstr != NULL) 464 1.4.2.2 yamt return; 465 1.4.2.2 yamt 466 1.4.2.2 yamt if ((ld = lockdebug_lookup(id, &lk)) == NULL) 467 1.4.2.2 yamt return; 468 1.4.2.2 yamt 469 1.4.2.2 yamt if (shared) { 470 1.4.2.2 yamt if (l->l_shlocks == 0) 471 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__, 472 1.4.2.2 yamt "no shared locks held by LWP"); 473 1.4.2.2 yamt if (ld->ld_shares == 0) 474 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__, 475 1.4.2.2 yamt "no shared holds on this lock"); 476 1.4.2.2 yamt l->l_shlocks--; 477 1.4.2.2 yamt ld->ld_shares--; 478 1.4.2.2 yamt } else { 479 1.4.2.2 yamt if ((ld->ld_flags & LD_LOCKED) == 0) 480 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__, "not locked"); 481 1.4.2.2 yamt 482 1.4.2.2 yamt if ((ld->ld_flags & LD_SLEEPER) != 0) { 483 1.4.2.2 yamt if (ld->ld_lwp != curlwp) 484 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__, 485 1.4.2.2 yamt "not held by current LWP"); 486 1.4.2.2 yamt ld->ld_flags &= ~LD_LOCKED; 487 1.4.2.2 yamt ld->ld_unlocked = where; 488 1.4.2.2 yamt ld->ld_lwp = NULL; 489 1.4.2.2 yamt curlwp->l_exlocks--; 490 1.4.2.2 yamt TAILQ_REMOVE(&ld_sleepers, ld, ld_chain); 491 1.4.2.2 yamt } else { 492 1.4.2.2 yamt if (ld->ld_cpu != (uint16_t)cpu_number()) 493 1.4.2.2 yamt lockdebug_abort1(ld, lk, __func__, 494 1.4.2.2 yamt "not held by current CPU"); 495 1.4.2.2 yamt ld->ld_flags &= ~LD_LOCKED; 496 1.4.2.2 yamt ld->ld_unlocked = where; 497 1.4.2.2 yamt ld->ld_lwp = NULL; 498 1.4.2.2 yamt curcpu()->ci_spin_locks2--; 499 1.4.2.2 yamt TAILQ_REMOVE(&ld_spinners, ld, ld_chain); 500 1.4.2.2 yamt } 501 1.4.2.2 yamt } 502 1.4.2.2 yamt 503 1.4.2.2 yamt lockdebug_unlock(lk); 504 1.4.2.2 yamt } 505 1.4.2.2 yamt 506 1.4.2.2 yamt /* 507 1.4.2.2 yamt * lockdebug_barrier: 508 1.4.2.2 yamt * 509 1.4.2.2 yamt * Panic if we hold more than one specified spin lock, and optionally, 510 1.4.2.2 yamt * if we hold sleep locks. 511 1.4.2.2 yamt */ 512 1.4.2.2 yamt void 513 1.4.2.2 yamt lockdebug_barrier(volatile void *spinlock, int slplocks) 514 1.4.2.2 yamt { 515 1.4.2.2 yamt struct lwp *l = curlwp; 516 1.4.2.2 yamt lockdebug_t *ld; 517 1.4.2.2 yamt uint16_t cpuno; 518 1.4.2.2 yamt 519 1.4.2.2 yamt if (panicstr != NULL) 520 1.4.2.2 yamt return; 521 1.4.2.2 yamt 522 1.4.2.2 yamt if (curcpu()->ci_spin_locks2 != 0) { 523 1.4.2.2 yamt cpuno = (uint16_t)cpu_number(); 524 1.4.2.2 yamt 525 1.4.2.2 yamt lockdebug_lock(&ld_spinner_lk); 526 1.4.2.2 yamt TAILQ_FOREACH(ld, &ld_spinners, ld_chain) { 527 1.4.2.2 yamt if (ld->ld_lock == spinlock) { 528 1.4.2.2 yamt if (ld->ld_cpu != cpuno) 529 1.4.2.2 yamt lockdebug_abort1(ld, &ld_spinner_lk, 530 1.4.2.2 yamt __func__, 531 1.4.2.2 yamt "not held by current CPU"); 532 1.4.2.2 yamt continue; 533 1.4.2.2 yamt } 534 1.4.2.2 yamt if (ld->ld_cpu == cpuno) 535 1.4.2.2 yamt lockdebug_abort1(ld, &ld_spinner_lk, 536 1.4.2.2 yamt __func__, "spin lock held"); 537 1.4.2.2 yamt } 538 1.4.2.2 yamt lockdebug_unlock(&ld_spinner_lk); 539 1.4.2.2 yamt } 540 1.4.2.2 yamt 541 1.4.2.2 yamt if (!slplocks) { 542 1.4.2.2 yamt if (l->l_exlocks != 0) { 543 1.4.2.2 yamt lockdebug_lock(&ld_sleeper_lk); 544 1.4.2.2 yamt TAILQ_FOREACH(ld, &ld_sleepers, ld_chain) { 545 1.4.2.2 yamt if (ld->ld_lwp == l) 546 1.4.2.2 yamt lockdebug_abort1(ld, &ld_sleeper_lk, 547 1.4.2.2 yamt __func__, "sleep lock held"); 548 1.4.2.2 yamt } 549 1.4.2.2 yamt lockdebug_unlock(&ld_sleeper_lk); 550 1.4.2.2 yamt } 551 1.4.2.2 yamt if (l->l_shlocks != 0) 552 1.4.2.2 yamt panic("lockdebug_barrier: holding %d shared locks", 553 1.4.2.2 yamt l->l_shlocks); 554 1.4.2.2 yamt } 555 1.4.2.2 yamt } 556 1.4.2.2 yamt 557 1.4.2.2 yamt /* 558 1.4.2.2 yamt * lockdebug_dump: 559 1.4.2.2 yamt * 560 1.4.2.2 yamt * Dump information about a lock on panic, or for DDB. 561 1.4.2.2 yamt */ 562 1.4.2.2 yamt static void 563 1.4.2.2 yamt lockdebug_dump(lockdebug_t *ld, void (*pr)(const char *, ...)) 564 1.4.2.2 yamt { 565 1.4.2.2 yamt int sleeper = (ld->ld_flags & LD_SLEEPER); 566 1.4.2.2 yamt 567 1.4.2.2 yamt (*pr)( 568 1.4.2.2 yamt "lock address : %#018lx type : %18s\n" 569 1.4.2.2 yamt "shared holds : %18u exclusive: %18u\n" 570 1.4.2.2 yamt "shares wanted: %18u exclusive: %18u\n" 571 1.4.2.2 yamt "current cpu : %18u last held: %18u\n" 572 1.4.2.2 yamt "current lwp : %#018lx last held: %#018lx\n" 573 1.4.2.2 yamt "last locked : %#018lx unlocked : %#018lx\n", 574 1.4.2.2 yamt (long)ld->ld_lock, (sleeper ? "sleep/adaptive" : "spin"), 575 1.4.2.2 yamt (unsigned)ld->ld_shares, ((ld->ld_flags & LD_LOCKED) != 0), 576 1.4.2.2 yamt (unsigned)ld->ld_shwant, (unsigned)ld->ld_exwant, 577 1.4.2.2 yamt (unsigned)cpu_number(), (unsigned)ld->ld_cpu, 578 1.4.2.2 yamt (long)curlwp, (long)ld->ld_lwp, 579 1.4.2.2 yamt (long)ld->ld_locked, (long)ld->ld_unlocked); 580 1.4.2.2 yamt 581 1.4.2.2 yamt if (ld->ld_lockops->lo_dump != NULL) 582 1.4.2.2 yamt (*ld->ld_lockops->lo_dump)(ld->ld_lock); 583 1.4.2.2 yamt 584 1.4.2.2 yamt if (sleeper) { 585 1.4.2.2 yamt (*pr)("\n"); 586 1.4.2.2 yamt turnstile_print(ld->ld_lock, pr); 587 1.4.2.2 yamt } 588 1.4.2.2 yamt } 589 1.4.2.2 yamt 590 1.4.2.2 yamt /* 591 1.4.2.2 yamt * lockdebug_dump: 592 1.4.2.2 yamt * 593 1.4.2.2 yamt * Dump information about a known lock. 594 1.4.2.2 yamt */ 595 1.4.2.2 yamt void 596 1.4.2.2 yamt lockdebug_abort1(lockdebug_t *ld, lockdebuglk_t *lk, const char *func, 597 1.4.2.2 yamt const char *msg) 598 1.4.2.2 yamt { 599 1.4.2.2 yamt 600 1.4.2.2 yamt printf_nolog("%s error: %s: %s\n\n", ld->ld_lockops->lo_name, 601 1.4.2.2 yamt func, msg); 602 1.4.2.2 yamt lockdebug_dump(ld, printf_nolog); 603 1.4.2.2 yamt lockdebug_unlock(lk); 604 1.4.2.2 yamt printf_nolog("\n"); 605 1.4.2.2 yamt panic("LOCKDEBUG"); 606 1.4.2.2 yamt } 607 1.4.2.2 yamt 608 1.4.2.2 yamt #endif /* LOCKDEBUG */ 609 1.4.2.2 yamt 610 1.4.2.2 yamt /* 611 1.4.2.2 yamt * lockdebug_lock_print: 612 1.4.2.2 yamt * 613 1.4.2.2 yamt * Handle the DDB 'show lock' command. 614 1.4.2.2 yamt */ 615 1.4.2.2 yamt #ifdef DDB 616 1.4.2.2 yamt void 617 1.4.2.2 yamt lockdebug_lock_print(void *addr, void (*pr)(const char *, ...)) 618 1.4.2.2 yamt { 619 1.4.2.2 yamt #ifdef LOCKDEBUG 620 1.4.2.2 yamt lockdebug_t *ld; 621 1.4.2.2 yamt 622 1.4.2.2 yamt TAILQ_FOREACH(ld, &ld_all, ld_achain) { 623 1.4.2.2 yamt if (ld->ld_lock == addr) { 624 1.4.2.2 yamt lockdebug_dump(ld, pr); 625 1.4.2.2 yamt return; 626 1.4.2.2 yamt } 627 1.4.2.2 yamt } 628 1.4.2.2 yamt (*pr)("Sorry, no record of a lock with address %p found.\n", addr); 629 1.4.2.2 yamt #else 630 1.4.2.2 yamt (*pr)("Sorry, kernel not built with the LOCKDEBUG option.\n"); 631 1.4.2.2 yamt #endif /* LOCKDEBUG */ 632 1.4.2.2 yamt } 633 1.4.2.2 yamt #endif /* DDB */ 634 1.4.2.2 yamt 635 1.4.2.2 yamt /* 636 1.4.2.2 yamt * lockdebug_abort: 637 1.4.2.2 yamt * 638 1.4.2.2 yamt * An error has been trapped - dump lock info and call panic(). 639 1.4.2.2 yamt */ 640 1.4.2.2 yamt void 641 1.4.2.2 yamt lockdebug_abort(int id, volatile void *lock, lockops_t *ops, 642 1.4.2.2 yamt const char *func, const char *msg) 643 1.4.2.2 yamt { 644 1.4.2.2 yamt #ifdef LOCKDEBUG 645 1.4.2.2 yamt lockdebug_t *ld; 646 1.4.2.2 yamt lockdebuglk_t *lk; 647 1.4.2.2 yamt 648 1.4.2.2 yamt if ((ld = lockdebug_lookup(id, &lk)) != NULL) { 649 1.4.2.2 yamt lockdebug_abort1(ld, lk, func, msg); 650 1.4.2.2 yamt /* NOTREACHED */ 651 1.4.2.2 yamt } 652 1.4.2.2 yamt #endif /* LOCKDEBUG */ 653 1.4.2.2 yamt 654 1.4.2.2 yamt printf_nolog("%s error: %s: %s\n\n" 655 1.4.2.2 yamt "lock address : %#018lx\n" 656 1.4.2.2 yamt "current cpu : %18d\n" 657 1.4.2.2 yamt "current lwp : %#018lx\n", 658 1.4.2.2 yamt ops->lo_name, func, msg, (long)lock, (int)cpu_number(), 659 1.4.2.2 yamt (long)curlwp); 660 1.4.2.2 yamt 661 1.4.2.2 yamt (*ops->lo_dump)(lock); 662 1.4.2.2 yamt 663 1.4.2.2 yamt printf_nolog("\n"); 664 1.4.2.2 yamt panic("lock error"); 665 1.4.2.2 yamt } 666
Indexes created Mon Sep 22 10:09:38 GMT 2025