lockstat.c revision 1.5.2.5
1 1.5.2.5 yamt /* $NetBSD: lockstat.c,v 1.5.2.5 2007/11/15 11:44:01 yamt Exp $ */ 2 1.5.2.2 yamt 3 1.5.2.2 yamt /*- 4 1.5.2.4 yamt * Copyright (c) 2006, 2007 The NetBSD Foundation, Inc. 5 1.5.2.2 yamt * All rights reserved. 6 1.5.2.2 yamt * 7 1.5.2.2 yamt * This code is derived from software contributed to The NetBSD Foundation 8 1.5.2.2 yamt * by Andrew Doran. 9 1.5.2.2 yamt * 10 1.5.2.2 yamt * Redistribution and use in source and binary forms, with or without 11 1.5.2.2 yamt * modification, are permitted provided that the following conditions 12 1.5.2.2 yamt * are met: 13 1.5.2.2 yamt * 1. Redistributions of source code must retain the above copyright 14 1.5.2.2 yamt * notice, this list of conditions and the following disclaimer. 15 1.5.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright 16 1.5.2.2 yamt * notice, this list of conditions and the following disclaimer in the 17 1.5.2.2 yamt * documentation and/or other materials provided with the distribution. 18 1.5.2.2 yamt * 3. All advertising materials mentioning features or use of this software 19 1.5.2.2 yamt * must display the following acknowledgement: 20 1.5.2.2 yamt * This product includes software developed by the NetBSD 21 1.5.2.2 yamt * Foundation, Inc. and its contributors. 22 1.5.2.2 yamt * 4. Neither the name of The NetBSD Foundation nor the names of its 23 1.5.2.2 yamt * contributors may be used to endorse or promote products derived 24 1.5.2.2 yamt * from this software without specific prior written permission. 25 1.5.2.2 yamt * 26 1.5.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 1.5.2.2 yamt * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 1.5.2.2 yamt * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 1.5.2.2 yamt * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 1.5.2.2 yamt * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 1.5.2.2 yamt * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 1.5.2.2 yamt * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 1.5.2.2 yamt * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 1.5.2.2 yamt * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 1.5.2.2 yamt * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 1.5.2.2 yamt * POSSIBILITY OF SUCH DAMAGE. 37 1.5.2.2 yamt */ 38 1.5.2.2 yamt 39 1.5.2.2 yamt /* 40 1.5.2.2 yamt * Lock statistics driver, providing kernel support for the lockstat(8) 41 1.5.2.2 yamt * command. 42 1.5.2.2 yamt * 43 1.5.2.5 yamt * We use a global lock word (lockstat_lock) to track device opens. 44 1.5.2.5 yamt * Only one thread can hold the device at a time, providing a global lock. 45 1.5.2.5 yamt * 46 1.5.2.2 yamt * XXX Timings for contention on sleep locks are currently incorrect. 47 1.5.2.2 yamt */ 48 1.5.2.2 yamt 49 1.5.2.2 yamt #include <sys/cdefs.h> 50 1.5.2.5 yamt __KERNEL_RCSID(0, "$NetBSD: lockstat.c,v 1.5.2.5 2007/11/15 11:44:01 yamt Exp $"); 51 1.5.2.2 yamt 52 1.5.2.2 yamt #include <sys/types.h> 53 1.5.2.2 yamt #include <sys/param.h> 54 1.5.2.2 yamt #include <sys/lock.h> 55 1.5.2.2 yamt #include <sys/proc.h> 56 1.5.2.2 yamt #include <sys/resourcevar.h> 57 1.5.2.2 yamt #include <sys/systm.h> 58 1.5.2.2 yamt #include <sys/kernel.h> 59 1.5.2.5 yamt #include <sys/kmem.h> 60 1.5.2.2 yamt #include <sys/conf.h> 61 1.5.2.2 yamt #include <sys/syslog.h> 62 1.5.2.2 yamt 63 1.5.2.2 yamt #include <dev/lockstat.h> 64 1.5.2.2 yamt 65 1.5.2.2 yamt #ifndef __HAVE_CPU_COUNTER 66 1.5.2.2 yamt #error CPU counters not available 67 1.5.2.2 yamt #endif 68 1.5.2.2 yamt 69 1.5.2.2 yamt #if LONG_BIT == 64 70 1.5.2.2 yamt #define LOCKSTAT_HASH_SHIFT 3 71 1.5.2.2 yamt #elif LONG_BIT == 32 72 1.5.2.2 yamt #define LOCKSTAT_HASH_SHIFT 2 73 1.5.2.2 yamt #endif 74 1.5.2.2 yamt 75 1.5.2.4 yamt #define LOCKSTAT_MINBUFS 1000 76 1.5.2.4 yamt #define LOCKSTAT_DEFBUFS 10000 77 1.5.2.4 yamt #define LOCKSTAT_MAXBUFS 50000 78 1.5.2.2 yamt 79 1.5.2.5 yamt #define LOCKSTAT_HASH_SIZE 128 80 1.5.2.2 yamt #define LOCKSTAT_HASH_MASK (LOCKSTAT_HASH_SIZE - 1) 81 1.5.2.2 yamt #define LOCKSTAT_HASH(key) \ 82 1.5.2.2 yamt ((key >> LOCKSTAT_HASH_SHIFT) & LOCKSTAT_HASH_MASK) 83 1.5.2.2 yamt 84 1.5.2.2 yamt typedef struct lscpu { 85 1.5.2.2 yamt SLIST_HEAD(, lsbuf) lc_free; 86 1.5.2.2 yamt u_int lc_overflow; 87 1.5.2.2 yamt LIST_HEAD(lslist, lsbuf) lc_hash[LOCKSTAT_HASH_SIZE]; 88 1.5.2.2 yamt } lscpu_t; 89 1.5.2.2 yamt 90 1.5.2.2 yamt typedef struct lslist lslist_t; 91 1.5.2.2 yamt 92 1.5.2.2 yamt void lockstatattach(int); 93 1.5.2.2 yamt void lockstat_start(lsenable_t *); 94 1.5.2.2 yamt int lockstat_alloc(lsenable_t *); 95 1.5.2.2 yamt void lockstat_init_tables(lsenable_t *); 96 1.5.2.2 yamt int lockstat_stop(lsdisable_t *); 97 1.5.2.2 yamt void lockstat_free(void); 98 1.5.2.2 yamt 99 1.5.2.2 yamt dev_type_open(lockstat_open); 100 1.5.2.2 yamt dev_type_close(lockstat_close); 101 1.5.2.2 yamt dev_type_read(lockstat_read); 102 1.5.2.2 yamt dev_type_ioctl(lockstat_ioctl); 103 1.5.2.2 yamt 104 1.5.2.2 yamt volatile u_int lockstat_enabled; 105 1.5.2.2 yamt uintptr_t lockstat_csstart; 106 1.5.2.2 yamt uintptr_t lockstat_csend; 107 1.5.2.2 yamt uintptr_t lockstat_csmask; 108 1.5.2.4 yamt uintptr_t lockstat_lamask; 109 1.5.2.2 yamt uintptr_t lockstat_lockstart; 110 1.5.2.2 yamt uintptr_t lockstat_lockend; 111 1.5.2.5 yamt __cpu_simple_lock_t lockstat_lock; 112 1.5.2.5 yamt lwp_t *lockstat_lwp; 113 1.5.2.2 yamt lsbuf_t *lockstat_baseb; 114 1.5.2.2 yamt size_t lockstat_sizeb; 115 1.5.2.2 yamt int lockstat_busy; 116 1.5.2.2 yamt struct timespec lockstat_stime; 117 1.5.2.2 yamt 118 1.5.2.2 yamt const struct cdevsw lockstat_cdevsw = { 119 1.5.2.2 yamt lockstat_open, lockstat_close, lockstat_read, nowrite, lockstat_ioctl, 120 1.5.2.5 yamt nostop, notty, nopoll, nommap, nokqfilter, D_OTHER | D_MPSAFE 121 1.5.2.2 yamt }; 122 1.5.2.2 yamt 123 1.5.2.2 yamt /* 124 1.5.2.2 yamt * Called when the pseudo-driver is attached. 125 1.5.2.2 yamt */ 126 1.5.2.2 yamt void 127 1.5.2.2 yamt lockstatattach(int nunits) 128 1.5.2.2 yamt { 129 1.5.2.2 yamt 130 1.5.2.2 yamt (void)nunits; 131 1.5.2.2 yamt 132 1.5.2.5 yamt __cpu_simple_lock_init(&lockstat_lock); 133 1.5.2.2 yamt } 134 1.5.2.2 yamt 135 1.5.2.2 yamt /* 136 1.5.2.2 yamt * Prepare the per-CPU tables for use, or clear down tables when tracing is 137 1.5.2.2 yamt * stopped. 138 1.5.2.2 yamt */ 139 1.5.2.2 yamt void 140 1.5.2.2 yamt lockstat_init_tables(lsenable_t *le) 141 1.5.2.2 yamt { 142 1.5.2.3 yamt int i, per, slop, cpuno; 143 1.5.2.2 yamt CPU_INFO_ITERATOR cii; 144 1.5.2.2 yamt struct cpu_info *ci; 145 1.5.2.2 yamt lscpu_t *lc; 146 1.5.2.2 yamt lsbuf_t *lb; 147 1.5.2.2 yamt 148 1.5.2.2 yamt KASSERT(!lockstat_enabled); 149 1.5.2.2 yamt 150 1.5.2.2 yamt for (CPU_INFO_FOREACH(cii, ci)) { 151 1.5.2.2 yamt if (ci->ci_lockstat != NULL) { 152 1.5.2.5 yamt kmem_free(ci->ci_lockstat, sizeof(lscpu_t)); 153 1.5.2.2 yamt ci->ci_lockstat = NULL; 154 1.5.2.2 yamt } 155 1.5.2.2 yamt } 156 1.5.2.2 yamt 157 1.5.2.2 yamt if (le == NULL) 158 1.5.2.2 yamt return; 159 1.5.2.2 yamt 160 1.5.2.2 yamt lb = lockstat_baseb; 161 1.5.2.2 yamt per = le->le_nbufs / ncpu; 162 1.5.2.2 yamt slop = le->le_nbufs - (per * ncpu); 163 1.5.2.2 yamt cpuno = 0; 164 1.5.2.2 yamt for (CPU_INFO_FOREACH(cii, ci)) { 165 1.5.2.5 yamt lc = kmem_alloc(sizeof(*lc), KM_SLEEP); 166 1.5.2.2 yamt lc->lc_overflow = 0; 167 1.5.2.2 yamt ci->ci_lockstat = lc; 168 1.5.2.2 yamt 169 1.5.2.2 yamt SLIST_INIT(&lc->lc_free); 170 1.5.2.2 yamt for (i = 0; i < LOCKSTAT_HASH_SIZE; i++) 171 1.5.2.2 yamt LIST_INIT(&lc->lc_hash[i]); 172 1.5.2.2 yamt 173 1.5.2.2 yamt for (i = per; i != 0; i--, lb++) { 174 1.5.2.2 yamt lb->lb_cpu = (uint16_t)cpuno; 175 1.5.2.2 yamt SLIST_INSERT_HEAD(&lc->lc_free, lb, lb_chain.slist); 176 1.5.2.2 yamt } 177 1.5.2.2 yamt if (--slop > 0) { 178 1.5.2.2 yamt lb->lb_cpu = (uint16_t)cpuno; 179 1.5.2.2 yamt SLIST_INSERT_HEAD(&lc->lc_free, lb, lb_chain.slist); 180 1.5.2.2 yamt lb++; 181 1.5.2.2 yamt } 182 1.5.2.2 yamt cpuno++; 183 1.5.2.2 yamt } 184 1.5.2.2 yamt } 185 1.5.2.2 yamt 186 1.5.2.2 yamt /* 187 1.5.2.2 yamt * Start collecting lock statistics. 188 1.5.2.2 yamt */ 189 1.5.2.2 yamt void 190 1.5.2.2 yamt lockstat_start(lsenable_t *le) 191 1.5.2.2 yamt { 192 1.5.2.2 yamt 193 1.5.2.2 yamt KASSERT(!lockstat_enabled); 194 1.5.2.2 yamt 195 1.5.2.2 yamt lockstat_init_tables(le); 196 1.5.2.2 yamt 197 1.5.2.2 yamt if ((le->le_flags & LE_CALLSITE) != 0) 198 1.5.2.2 yamt lockstat_csmask = (uintptr_t)-1LL; 199 1.5.2.2 yamt else 200 1.5.2.2 yamt lockstat_csmask = 0; 201 1.5.2.2 yamt 202 1.5.2.4 yamt if ((le->le_flags & LE_LOCK) != 0) 203 1.5.2.4 yamt lockstat_lamask = (uintptr_t)-1LL; 204 1.5.2.4 yamt else 205 1.5.2.4 yamt lockstat_lamask = 0; 206 1.5.2.4 yamt 207 1.5.2.2 yamt lockstat_csstart = le->le_csstart; 208 1.5.2.2 yamt lockstat_csend = le->le_csend; 209 1.5.2.2 yamt lockstat_lockstart = le->le_lockstart; 210 1.5.2.3 yamt lockstat_lockstart = le->le_lockstart; 211 1.5.2.2 yamt lockstat_lockend = le->le_lockend; 212 1.5.2.2 yamt mb_memory(); 213 1.5.2.2 yamt getnanotime(&lockstat_stime); 214 1.5.2.2 yamt lockstat_enabled = le->le_mask; 215 1.5.2.2 yamt mb_write(); 216 1.5.2.2 yamt } 217 1.5.2.2 yamt 218 1.5.2.2 yamt /* 219 1.5.2.2 yamt * Stop collecting lock statistics. 220 1.5.2.2 yamt */ 221 1.5.2.2 yamt int 222 1.5.2.2 yamt lockstat_stop(lsdisable_t *ld) 223 1.5.2.2 yamt { 224 1.5.2.2 yamt CPU_INFO_ITERATOR cii; 225 1.5.2.2 yamt struct cpu_info *ci; 226 1.5.2.2 yamt u_int cpuno, overflow; 227 1.5.2.2 yamt struct timespec ts; 228 1.5.2.2 yamt int error; 229 1.5.2.2 yamt 230 1.5.2.2 yamt KASSERT(lockstat_enabled); 231 1.5.2.2 yamt 232 1.5.2.2 yamt /* 233 1.5.2.2 yamt * Set enabled false, force a write barrier, and wait for other CPUs 234 1.5.2.2 yamt * to exit lockstat_event(). 235 1.5.2.2 yamt */ 236 1.5.2.2 yamt lockstat_enabled = 0; 237 1.5.2.5 yamt mb_write(); 238 1.5.2.2 yamt getnanotime(&ts); 239 1.5.2.2 yamt tsleep(&lockstat_stop, PPAUSE, "lockstat", mstohz(10)); 240 1.5.2.2 yamt 241 1.5.2.2 yamt /* 242 1.5.2.2 yamt * Did we run out of buffers while tracing? 243 1.5.2.2 yamt */ 244 1.5.2.2 yamt overflow = 0; 245 1.5.2.2 yamt for (CPU_INFO_FOREACH(cii, ci)) 246 1.5.2.2 yamt overflow += ((lscpu_t *)ci->ci_lockstat)->lc_overflow; 247 1.5.2.2 yamt 248 1.5.2.2 yamt if (overflow != 0) { 249 1.5.2.2 yamt error = EOVERFLOW; 250 1.5.2.2 yamt log(LOG_NOTICE, "lockstat: %d buffer allocations failed\n", 251 1.5.2.2 yamt overflow); 252 1.5.2.2 yamt } else 253 1.5.2.2 yamt error = 0; 254 1.5.2.2 yamt 255 1.5.2.2 yamt lockstat_init_tables(NULL); 256 1.5.2.2 yamt 257 1.5.2.2 yamt if (ld == NULL) 258 1.5.2.5 yamt return error; 259 1.5.2.2 yamt 260 1.5.2.2 yamt /* 261 1.5.2.2 yamt * Fill out the disable struct for the caller. 262 1.5.2.2 yamt */ 263 1.5.2.2 yamt timespecsub(&ts, &lockstat_stime, &ld->ld_time); 264 1.5.2.2 yamt ld->ld_size = lockstat_sizeb; 265 1.5.2.2 yamt 266 1.5.2.2 yamt cpuno = 0; 267 1.5.2.2 yamt for (CPU_INFO_FOREACH(cii, ci)) { 268 1.5.2.2 yamt if (cpuno > sizeof(ld->ld_freq) / sizeof(ld->ld_freq[0])) { 269 1.5.2.2 yamt log(LOG_WARNING, "lockstat: too many CPUs\n"); 270 1.5.2.2 yamt break; 271 1.5.2.2 yamt } 272 1.5.2.2 yamt ld->ld_freq[cpuno++] = cpu_frequency(ci); 273 1.5.2.2 yamt } 274 1.5.2.2 yamt 275 1.5.2.5 yamt return error; 276 1.5.2.2 yamt } 277 1.5.2.2 yamt 278 1.5.2.2 yamt /* 279 1.5.2.2 yamt * Allocate buffers for lockstat_start(). 280 1.5.2.2 yamt */ 281 1.5.2.2 yamt int 282 1.5.2.2 yamt lockstat_alloc(lsenable_t *le) 283 1.5.2.2 yamt { 284 1.5.2.2 yamt lsbuf_t *lb; 285 1.5.2.2 yamt size_t sz; 286 1.5.2.2 yamt 287 1.5.2.2 yamt KASSERT(!lockstat_enabled); 288 1.5.2.2 yamt lockstat_free(); 289 1.5.2.2 yamt 290 1.5.2.2 yamt sz = sizeof(*lb) * le->le_nbufs; 291 1.5.2.2 yamt 292 1.5.2.5 yamt lb = kmem_zalloc(sz, KM_SLEEP); 293 1.5.2.2 yamt if (lb == NULL) 294 1.5.2.2 yamt return (ENOMEM); 295 1.5.2.2 yamt 296 1.5.2.2 yamt KASSERT(!lockstat_enabled); 297 1.5.2.2 yamt KASSERT(lockstat_baseb == NULL); 298 1.5.2.2 yamt lockstat_sizeb = sz; 299 1.5.2.2 yamt lockstat_baseb = lb; 300 1.5.2.2 yamt 301 1.5.2.2 yamt return (0); 302 1.5.2.2 yamt } 303 1.5.2.2 yamt 304 1.5.2.2 yamt /* 305 1.5.2.2 yamt * Free allocated buffers after tracing has stopped. 306 1.5.2.2 yamt */ 307 1.5.2.2 yamt void 308 1.5.2.2 yamt lockstat_free(void) 309 1.5.2.2 yamt { 310 1.5.2.2 yamt 311 1.5.2.2 yamt KASSERT(!lockstat_enabled); 312 1.5.2.2 yamt 313 1.5.2.2 yamt if (lockstat_baseb != NULL) { 314 1.5.2.5 yamt kmem_free(lockstat_baseb, lockstat_sizeb); 315 1.5.2.2 yamt lockstat_baseb = NULL; 316 1.5.2.2 yamt } 317 1.5.2.2 yamt } 318 1.5.2.2 yamt 319 1.5.2.2 yamt /* 320 1.5.2.2 yamt * Main entry point from lock primatives. 321 1.5.2.2 yamt */ 322 1.5.2.2 yamt void 323 1.5.2.2 yamt lockstat_event(uintptr_t lock, uintptr_t callsite, u_int flags, u_int count, 324 1.5.2.3 yamt uint64_t cycles) 325 1.5.2.2 yamt { 326 1.5.2.2 yamt lslist_t *ll; 327 1.5.2.2 yamt lscpu_t *lc; 328 1.5.2.2 yamt lsbuf_t *lb; 329 1.5.2.2 yamt u_int event; 330 1.5.2.2 yamt int s; 331 1.5.2.2 yamt 332 1.5.2.2 yamt if ((flags & lockstat_enabled) != flags || count == 0) 333 1.5.2.2 yamt return; 334 1.5.2.2 yamt if (lock < lockstat_lockstart || lock > lockstat_lockend) 335 1.5.2.2 yamt return; 336 1.5.2.2 yamt if (callsite < lockstat_csstart || callsite > lockstat_csend) 337 1.5.2.2 yamt return; 338 1.5.2.2 yamt 339 1.5.2.2 yamt callsite &= lockstat_csmask; 340 1.5.2.4 yamt lock &= lockstat_lamask; 341 1.5.2.2 yamt 342 1.5.2.2 yamt /* 343 1.5.2.2 yamt * Find the table for this lock+callsite pair, and try to locate a 344 1.5.2.2 yamt * buffer with the same key. 345 1.5.2.2 yamt */ 346 1.5.2.5 yamt s = splhigh(); 347 1.5.2.2 yamt lc = curcpu()->ci_lockstat; 348 1.5.2.2 yamt ll = &lc->lc_hash[LOCKSTAT_HASH(lock ^ callsite)]; 349 1.5.2.2 yamt event = (flags & LB_EVENT_MASK) - 1; 350 1.5.2.2 yamt 351 1.5.2.2 yamt LIST_FOREACH(lb, ll, lb_chain.list) { 352 1.5.2.2 yamt if (lb->lb_lock == lock && lb->lb_callsite == callsite) 353 1.5.2.2 yamt break; 354 1.5.2.2 yamt } 355 1.5.2.2 yamt 356 1.5.2.2 yamt if (lb != NULL) { 357 1.5.2.2 yamt /* 358 1.5.2.2 yamt * We found a record. Move it to the front of the list, as 359 1.5.2.2 yamt * we're likely to hit it again soon. 360 1.5.2.2 yamt */ 361 1.5.2.2 yamt if (lb != LIST_FIRST(ll)) { 362 1.5.2.2 yamt LIST_REMOVE(lb, lb_chain.list); 363 1.5.2.2 yamt LIST_INSERT_HEAD(ll, lb, lb_chain.list); 364 1.5.2.2 yamt } 365 1.5.2.2 yamt lb->lb_counts[event] += count; 366 1.5.2.3 yamt lb->lb_times[event] += cycles; 367 1.5.2.2 yamt } else if ((lb = SLIST_FIRST(&lc->lc_free)) != NULL) { 368 1.5.2.2 yamt /* 369 1.5.2.2 yamt * Pinch a new buffer and fill it out. 370 1.5.2.2 yamt */ 371 1.5.2.2 yamt SLIST_REMOVE_HEAD(&lc->lc_free, lb_chain.slist); 372 1.5.2.2 yamt LIST_INSERT_HEAD(ll, lb, lb_chain.list); 373 1.5.2.2 yamt lb->lb_flags = (uint16_t)flags; 374 1.5.2.2 yamt lb->lb_lock = lock; 375 1.5.2.2 yamt lb->lb_callsite = callsite; 376 1.5.2.2 yamt lb->lb_counts[event] = count; 377 1.5.2.3 yamt lb->lb_times[event] = cycles; 378 1.5.2.2 yamt } else { 379 1.5.2.2 yamt /* 380 1.5.2.2 yamt * We didn't find a buffer and there were none free. 381 1.5.2.2 yamt * lockstat_stop() will notice later on and report the 382 1.5.2.2 yamt * error. 383 1.5.2.2 yamt */ 384 1.5.2.2 yamt lc->lc_overflow++; 385 1.5.2.2 yamt } 386 1.5.2.2 yamt 387 1.5.2.2 yamt splx(s); 388 1.5.2.2 yamt } 389 1.5.2.2 yamt 390 1.5.2.2 yamt /* 391 1.5.2.2 yamt * Accept an open() on /dev/lockstat. 392 1.5.2.2 yamt */ 393 1.5.2.2 yamt int 394 1.5.2.5 yamt lockstat_open(dev_t dev, int flag, int mode, lwp_t *l) 395 1.5.2.2 yamt { 396 1.5.2.2 yamt 397 1.5.2.5 yamt if (!__cpu_simple_lock_try(&lockstat_lock)) 398 1.5.2.5 yamt return EBUSY; 399 1.5.2.5 yamt lockstat_lwp = curlwp; 400 1.5.2.5 yamt return 0; 401 1.5.2.2 yamt } 402 1.5.2.2 yamt 403 1.5.2.2 yamt /* 404 1.5.2.2 yamt * Accept the last close() on /dev/lockstat. 405 1.5.2.2 yamt */ 406 1.5.2.2 yamt int 407 1.5.2.5 yamt lockstat_close(dev_t dev, int flag, int mode, lwp_t *l) 408 1.5.2.2 yamt { 409 1.5.2.2 yamt 410 1.5.2.5 yamt lockstat_lwp = NULL; 411 1.5.2.5 yamt __cpu_simple_unlock(&lockstat_lock); 412 1.5.2.5 yamt return 0; 413 1.5.2.2 yamt } 414 1.5.2.2 yamt 415 1.5.2.2 yamt /* 416 1.5.2.2 yamt * Handle control operations. 417 1.5.2.2 yamt */ 418 1.5.2.2 yamt int 419 1.5.2.5 yamt lockstat_ioctl(dev_t dev, u_long cmd, void *data, int flag, lwp_t *l) 420 1.5.2.2 yamt { 421 1.5.2.2 yamt lsenable_t *le; 422 1.5.2.2 yamt int error; 423 1.5.2.2 yamt 424 1.5.2.5 yamt if (lockstat_lwp != curlwp) 425 1.5.2.5 yamt return EBUSY; 426 1.5.2.2 yamt 427 1.5.2.2 yamt switch (cmd) { 428 1.5.2.2 yamt case IOC_LOCKSTAT_GVERSION: 429 1.5.2.2 yamt *(int *)data = LS_VERSION; 430 1.5.2.2 yamt error = 0; 431 1.5.2.2 yamt break; 432 1.5.2.2 yamt 433 1.5.2.2 yamt case IOC_LOCKSTAT_ENABLE: 434 1.5.2.2 yamt le = (lsenable_t *)data; 435 1.5.2.2 yamt 436 1.5.2.2 yamt if (!cpu_hascounter()) { 437 1.5.2.2 yamt error = ENODEV; 438 1.5.2.2 yamt break; 439 1.5.2.2 yamt } 440 1.5.2.2 yamt if (lockstat_enabled) { 441 1.5.2.2 yamt error = EBUSY; 442 1.5.2.2 yamt break; 443 1.5.2.2 yamt } 444 1.5.2.2 yamt 445 1.5.2.2 yamt /* 446 1.5.2.2 yamt * Sanitize the arguments passed in and set up filtering. 447 1.5.2.2 yamt */ 448 1.5.2.2 yamt if (le->le_nbufs == 0) 449 1.5.2.2 yamt le->le_nbufs = LOCKSTAT_DEFBUFS; 450 1.5.2.2 yamt else if (le->le_nbufs > LOCKSTAT_MAXBUFS || 451 1.5.2.2 yamt le->le_nbufs < LOCKSTAT_MINBUFS) { 452 1.5.2.2 yamt error = EINVAL; 453 1.5.2.2 yamt break; 454 1.5.2.2 yamt } 455 1.5.2.2 yamt if ((le->le_flags & LE_ONE_CALLSITE) == 0) { 456 1.5.2.2 yamt le->le_csstart = 0; 457 1.5.2.2 yamt le->le_csend = le->le_csstart - 1; 458 1.5.2.2 yamt } 459 1.5.2.2 yamt if ((le->le_flags & LE_ONE_LOCK) == 0) { 460 1.5.2.2 yamt le->le_lockstart = 0; 461 1.5.2.2 yamt le->le_lockend = le->le_lockstart - 1; 462 1.5.2.2 yamt } 463 1.5.2.2 yamt if ((le->le_mask & LB_EVENT_MASK) == 0) 464 1.5.2.5 yamt return EINVAL; 465 1.5.2.2 yamt if ((le->le_mask & LB_LOCK_MASK) == 0) 466 1.5.2.5 yamt return EINVAL; 467 1.5.2.2 yamt 468 1.5.2.2 yamt /* 469 1.5.2.2 yamt * Start tracing. 470 1.5.2.2 yamt */ 471 1.5.2.2 yamt if ((error = lockstat_alloc(le)) == 0) 472 1.5.2.2 yamt lockstat_start(le); 473 1.5.2.2 yamt break; 474 1.5.2.2 yamt 475 1.5.2.2 yamt case IOC_LOCKSTAT_DISABLE: 476 1.5.2.2 yamt if (!lockstat_enabled) 477 1.5.2.2 yamt error = EINVAL; 478 1.5.2.2 yamt else 479 1.5.2.2 yamt error = lockstat_stop((lsdisable_t *)data); 480 1.5.2.2 yamt break; 481 1.5.2.2 yamt 482 1.5.2.2 yamt default: 483 1.5.2.2 yamt error = ENOTTY; 484 1.5.2.2 yamt break; 485 1.5.2.2 yamt } 486 1.5.2.2 yamt 487 1.5.2.2 yamt return error; 488 1.5.2.2 yamt } 489 1.5.2.2 yamt 490 1.5.2.2 yamt /* 491 1.5.2.2 yamt * Copy buffers out to user-space. 492 1.5.2.2 yamt */ 493 1.5.2.2 yamt int 494 1.5.2.2 yamt lockstat_read(dev_t dev, struct uio *uio, int flag) 495 1.5.2.2 yamt { 496 1.5.2.2 yamt 497 1.5.2.5 yamt if (curlwp != lockstat_lwp || lockstat_enabled) 498 1.5.2.5 yamt return EBUSY; 499 1.5.2.5 yamt return uiomove(lockstat_baseb, lockstat_sizeb, uio); 500 1.5.2.2 yamt } 501
Indexes created Thu Oct 02 10:09:58 GMT 2025