1 /*- 2 * Copyright (c) 2000 John Baldwin <jhb@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the author nor the names of any co-contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 /* 31 * This module holds the global variables used by KTR and the ktr_tracepoint() 32 * function that does the actual tracing. 33 */ 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include "opt_ddb.h" 39 #include "opt_ktr.h" 40 #include "opt_alq.h" 41 42 #include <sys/param.h> 43 #include <sys/queue.h> 44 #include <sys/alq.h> 45 #include <sys/cons.h> 46 #include <sys/cpuset.h> 47 #include <sys/kernel.h> 48 #include <sys/ktr.h> 49 #include <sys/libkern.h> 50 #include <sys/lock.h> 51 #include <sys/malloc.h> 52 #include <sys/mutex.h> 53 #include <sys/proc.h> 54 #include <sys/smp.h> 55 #include <sys/sysctl.h> 56 #include <sys/systm.h> 57 #include <sys/time.h> 58 59 #include <machine/cpu.h> 60 #ifdef __sparc64__ 61 #include <machine/ktr.h> 62 #endif 63 64 #ifdef DDB 65 #include <ddb/ddb.h> 66 #include <ddb/db_output.h> 67 #endif 68 69 #ifndef KTR_BOOT_ENTRIES 70 #define KTR_BOOT_ENTRIES 1024 71 #endif 72 73 #ifndef KTR_ENTRIES 74 #define KTR_ENTRIES 1024 75 #endif 76 77 /* Limit the allocations to something manageable. */ 78 #define KTR_ENTRIES_MAX (8 * 1024 * 1024) 79 80 #ifndef KTR_MASK 81 #define KTR_MASK (0) 82 #endif 83 84 #ifndef KTR_CPUMASK 85 #define KTR_CPUMASK CPUSET_FSET 86 #endif 87 88 #ifndef KTR_TIME 89 #define KTR_TIME get_cyclecount() 90 #endif 91 92 #ifndef KTR_CPU 93 #define KTR_CPU PCPU_GET(cpuid) 94 #endif 95 96 static MALLOC_DEFINE(M_KTR, "KTR", "KTR"); 97 98 FEATURE(ktr, "Kernel support for KTR kernel tracing facility"); 99 100 volatile int ktr_idx = 0; 101 int ktr_mask = KTR_MASK; 102 int ktr_compile = KTR_COMPILE; 103 int ktr_entries = KTR_BOOT_ENTRIES; 104 int ktr_version = KTR_VERSION; 105 struct ktr_entry ktr_buf_init[KTR_BOOT_ENTRIES]; 106 struct ktr_entry *ktr_buf = ktr_buf_init; 107 cpuset_t ktr_cpumask = CPUSET_T_INITIALIZER(KTR_CPUMASK); 108 static char ktr_cpumask_str[CPUSETBUFSIZ]; 109 110 TUNABLE_INT("debug.ktr.mask", &ktr_mask); 111 112 TUNABLE_STR("debug.ktr.cpumask", ktr_cpumask_str, sizeof(ktr_cpumask_str)); 113 114 static SYSCTL_NODE(_debug, OID_AUTO, ktr, CTLFLAG_RD, 0, "KTR options"); 115 116 SYSCTL_INT(_debug_ktr, OID_AUTO, version, CTLFLAG_RD, 117 &ktr_version, 0, "Version of the KTR interface"); 118 119 SYSCTL_UINT(_debug_ktr, OID_AUTO, compile, CTLFLAG_RD, 120 &ktr_compile, 0, "Bitmask of KTR event classes compiled into the kernel"); 121 122 static void 123 ktr_cpumask_initializer(void *dummy __unused) 124 { 125 126 /* 127 * TUNABLE_STR() runs with SI_ORDER_MIDDLE priority, thus it must be 128 * already set, if necessary. 129 */ 130 if (ktr_cpumask_str[0] != '\0' && 131 cpusetobj_strscan(&ktr_cpumask, ktr_cpumask_str) == -1) 132 CPU_FILL(&ktr_cpumask); 133 } 134 SYSINIT(ktr_cpumask_initializer, SI_SUB_TUNABLES, SI_ORDER_ANY, 135 ktr_cpumask_initializer, NULL); 136 137 static int 138 sysctl_debug_ktr_cpumask(SYSCTL_HANDLER_ARGS) 139 { 140 char lktr_cpumask_str[CPUSETBUFSIZ]; 141 cpuset_t imask; 142 int error; 143 144 cpusetobj_strprint(lktr_cpumask_str, &ktr_cpumask); 145 error = sysctl_handle_string(oidp, lktr_cpumask_str, 146 sizeof(lktr_cpumask_str), req); 147 if (error != 0 || req->newptr == NULL) 148 return (error); 149 if (cpusetobj_strscan(&imask, lktr_cpumask_str) == -1) 150 return (EINVAL); 151 CPU_COPY(&imask, &ktr_cpumask); 152 153 return (error); 154 } 155 SYSCTL_PROC(_debug_ktr, OID_AUTO, cpumask, 156 CTLFLAG_RW | CTLFLAG_MPSAFE | CTLTYPE_STRING, NULL, 0, 157 sysctl_debug_ktr_cpumask, "S", 158 "Bitmask of CPUs on which KTR logging is enabled"); 159 160 static int 161 sysctl_debug_ktr_clear(SYSCTL_HANDLER_ARGS) 162 { 163 int clear, error; 164 165 clear = 0; 166 error = sysctl_handle_int(oidp, &clear, 0, req); 167 if (error || !req->newptr) 168 return (error); 169 170 if (clear) { 171 bzero(ktr_buf, sizeof(*ktr_buf) * ktr_entries); 172 ktr_idx = 0; 173 } 174 175 return (error); 176 } 177 SYSCTL_PROC(_debug_ktr, OID_AUTO, clear, CTLTYPE_INT|CTLFLAG_RW, 0, 0, 178 sysctl_debug_ktr_clear, "I", "Clear KTR Buffer"); 179 180 /* 181 * This is a sysctl proc so that it is serialized as !MPSAFE along with 182 * the other ktr sysctl procs. 183 */ 184 static int 185 sysctl_debug_ktr_mask(SYSCTL_HANDLER_ARGS) 186 { 187 int mask, error; 188 189 mask = ktr_mask; 190 error = sysctl_handle_int(oidp, &mask, 0, req); 191 if (error || !req->newptr) 192 return (error); 193 ktr_mask = mask; 194 return (error); 195 } 196 197 SYSCTL_PROC(_debug_ktr, OID_AUTO, mask, CTLTYPE_UINT|CTLFLAG_RW, 0, 0, 198 sysctl_debug_ktr_mask, "IU", 199 "Bitmask of KTR event classes for which logging is enabled"); 200 201 #if KTR_ENTRIES > KTR_BOOT_ENTRIES 202 /* 203 * A simplified version of sysctl_debug_ktr_entries. 204 * No need to care about SMP, scheduling, etc. 205 */ 206 static void 207 ktr_entries_initializer(void *dummy __unused) 208 { 209 int mask; 210 211 /* Temporarily disable ktr in case malloc() is being traced. */ 212 mask = ktr_mask; 213 ktr_mask = 0; 214 ktr_buf = malloc(sizeof(*ktr_buf) * KTR_ENTRIES, M_KTR, 215 M_WAITOK | M_ZERO); 216 memcpy(ktr_buf, ktr_buf_init + ktr_idx, 217 (KTR_BOOT_ENTRIES - ktr_idx) * sizeof(*ktr_buf)); 218 if (ktr_idx != 0) 219 memcpy(ktr_buf + KTR_BOOT_ENTRIES - ktr_idx, ktr_buf_init, 220 ktr_idx * sizeof(*ktr_buf)); 221 ktr_entries = KTR_ENTRIES; 222 ktr_mask = mask; 223 } 224 SYSINIT(ktr_entries_initializer, SI_SUB_KMEM, SI_ORDER_ANY, 225 ktr_entries_initializer, NULL); 226 #endif 227 228 static int 229 sysctl_debug_ktr_entries(SYSCTL_HANDLER_ARGS) 230 { 231 int entries, error, mask; 232 struct ktr_entry *buf, *oldbuf; 233 234 entries = ktr_entries; 235 error = sysctl_handle_int(oidp, &entries, 0, req); 236 if (error || !req->newptr) 237 return (error); 238 if (entries > KTR_ENTRIES_MAX) 239 return (ERANGE); 240 /* Disable ktr temporarily. */ 241 mask = ktr_mask; 242 atomic_store_rel_int(&ktr_mask, 0); 243 /* Wait for threads to go idle. */ 244 if ((error = quiesce_all_cpus("ktrent", PCATCH)) != 0) { 245 ktr_mask = mask; 246 return (error); 247 } 248 if (ktr_buf != ktr_buf_init) 249 oldbuf = ktr_buf; 250 else 251 oldbuf = NULL; 252 /* Allocate a new buffer. */ 253 buf = malloc(sizeof(*buf) * entries, M_KTR, M_WAITOK | M_ZERO); 254 /* Install the new buffer and restart ktr. */ 255 ktr_buf = buf; 256 ktr_entries = entries; 257 ktr_idx = 0; 258 atomic_store_rel_int(&ktr_mask, mask); 259 if (oldbuf != NULL) 260 free(oldbuf, M_KTR); 261 262 return (error); 263 } 264 265 SYSCTL_PROC(_debug_ktr, OID_AUTO, entries, CTLTYPE_INT|CTLFLAG_RW, 0, 0, 266 sysctl_debug_ktr_entries, "I", "Number of entries in the KTR buffer"); 267 268 #ifdef KTR_VERBOSE 269 int ktr_verbose = KTR_VERBOSE; 270 TUNABLE_INT("debug.ktr.verbose", &ktr_verbose); 271 SYSCTL_INT(_debug_ktr, OID_AUTO, verbose, CTLFLAG_RW, &ktr_verbose, 0, ""); 272 #endif 273 274 #ifdef KTR_ALQ 275 struct alq *ktr_alq; 276 char ktr_alq_file[MAXPATHLEN] = "/tmp/ktr.out"; 277 int ktr_alq_cnt = 0; 278 int ktr_alq_depth = KTR_ENTRIES; 279 int ktr_alq_enabled = 0; 280 int ktr_alq_failed = 0; 281 int ktr_alq_max = 0; 282 283 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_max, CTLFLAG_RW, &ktr_alq_max, 0, 284 "Maximum number of entries to write"); 285 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_cnt, CTLFLAG_RD, &ktr_alq_cnt, 0, 286 "Current number of written entries"); 287 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_failed, CTLFLAG_RD, &ktr_alq_failed, 0, 288 "Number of times we overran the buffer"); 289 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_depth, CTLFLAG_RW, &ktr_alq_depth, 0, 290 "Number of items in the write buffer"); 291 SYSCTL_STRING(_debug_ktr, OID_AUTO, alq_file, CTLFLAG_RW, ktr_alq_file, 292 sizeof(ktr_alq_file), "KTR logging file"); 293 294 static int 295 sysctl_debug_ktr_alq_enable(SYSCTL_HANDLER_ARGS) 296 { 297 int error; 298 int enable; 299 300 enable = ktr_alq_enabled; 301 302 error = sysctl_handle_int(oidp, &enable, 0, req); 303 if (error || !req->newptr) 304 return (error); 305 306 if (enable) { 307 if (ktr_alq_enabled) 308 return (0); 309 error = alq_open(&ktr_alq, (const char *)ktr_alq_file, 310 req->td->td_ucred, ALQ_DEFAULT_CMODE, 311 sizeof(struct ktr_entry), ktr_alq_depth); 312 if (error == 0) { 313 ktr_alq_cnt = 0; 314 ktr_alq_failed = 0; 315 ktr_alq_enabled = 1; 316 } 317 } else { 318 if (ktr_alq_enabled == 0) 319 return (0); 320 ktr_alq_enabled = 0; 321 alq_close(ktr_alq); 322 ktr_alq = NULL; 323 } 324 325 return (error); 326 } 327 SYSCTL_PROC(_debug_ktr, OID_AUTO, alq_enable, 328 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_debug_ktr_alq_enable, 329 "I", "Enable KTR logging"); 330 #endif 331 332 void 333 ktr_tracepoint(u_int mask, const char *file, int line, const char *format, 334 u_long arg1, u_long arg2, u_long arg3, u_long arg4, u_long arg5, 335 u_long arg6) 336 { 337 struct ktr_entry *entry; 338 #ifdef KTR_ALQ 339 struct ale *ale = NULL; 340 #endif 341 int newindex, saveindex; 342 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 343 struct thread *td; 344 #endif 345 int cpu; 346 347 if (panicstr) 348 return; 349 if ((ktr_mask & mask) == 0 || ktr_buf == NULL) 350 return; 351 cpu = KTR_CPU; 352 if (!CPU_ISSET(cpu, &ktr_cpumask)) 353 return; 354 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 355 td = curthread; 356 if (td->td_pflags & TDP_INKTR) 357 return; 358 td->td_pflags |= TDP_INKTR; 359 #endif 360 #ifdef KTR_ALQ 361 if (ktr_alq_enabled) { 362 if (td->td_critnest == 0 && 363 (td->td_flags & TDF_IDLETD) == 0 && 364 td != ald_thread) { 365 if (ktr_alq_max && ktr_alq_cnt > ktr_alq_max) 366 goto done; 367 if ((ale = alq_get(ktr_alq, ALQ_NOWAIT)) == NULL) { 368 ktr_alq_failed++; 369 goto done; 370 } 371 ktr_alq_cnt++; 372 entry = (struct ktr_entry *)ale->ae_data; 373 } else { 374 goto done; 375 } 376 } else 377 #endif 378 { 379 do { 380 saveindex = ktr_idx; 381 newindex = (saveindex + 1) % ktr_entries; 382 } while (atomic_cmpset_rel_int(&ktr_idx, saveindex, newindex) == 0); 383 entry = &ktr_buf[saveindex]; 384 } 385 entry->ktr_timestamp = KTR_TIME; 386 entry->ktr_cpu = cpu; 387 entry->ktr_thread = curthread; 388 if (file != NULL) 389 while (strncmp(file, "../", 3) == 0) 390 file += 3; 391 entry->ktr_file = file; 392 entry->ktr_line = line; 393 #ifdef KTR_VERBOSE 394 if (ktr_verbose) { 395 #ifdef SMP 396 printf("cpu%d ", cpu); 397 #endif 398 if (ktr_verbose > 1) { 399 printf("%s.%d\t", entry->ktr_file, 400 entry->ktr_line); 401 } 402 printf(format, arg1, arg2, arg3, arg4, arg5, arg6); 403 printf("\n"); 404 } 405 #endif 406 entry->ktr_desc = format; 407 entry->ktr_parms[0] = arg1; 408 entry->ktr_parms[1] = arg2; 409 entry->ktr_parms[2] = arg3; 410 entry->ktr_parms[3] = arg4; 411 entry->ktr_parms[4] = arg5; 412 entry->ktr_parms[5] = arg6; 413 #ifdef KTR_ALQ 414 if (ktr_alq_enabled && ale) 415 alq_post(ktr_alq, ale); 416 done: 417 #endif 418 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 419 td->td_pflags &= ~TDP_INKTR; 420 #endif 421 } 422 423 #ifdef DDB 424 425 struct tstate { 426 int cur; 427 int first; 428 }; 429 static struct tstate tstate; 430 static int db_ktr_verbose; 431 static int db_mach_vtrace(void); 432 433 DB_SHOW_COMMAND(ktr, db_ktr_all) 434 { 435 436 tstate.cur = (ktr_idx - 1) % ktr_entries; 437 tstate.first = -1; 438 db_ktr_verbose = 0; 439 db_ktr_verbose |= (strchr(modif, 'v') != NULL) ? 2 : 0; 440 db_ktr_verbose |= (strchr(modif, 'V') != NULL) ? 1 : 0; /* just timestap please */ 441 if (strchr(modif, 'a') != NULL) { 442 db_disable_pager(); 443 while (cncheckc() != -1) 444 if (db_mach_vtrace() == 0) 445 break; 446 } else { 447 while (!db_pager_quit) 448 if (db_mach_vtrace() == 0) 449 break; 450 } 451 } 452 453 static int 454 db_mach_vtrace(void) 455 { 456 struct ktr_entry *kp; 457 458 if (tstate.cur == tstate.first || ktr_buf == NULL) { 459 db_printf("--- End of trace buffer ---\n"); 460 return (0); 461 } 462 kp = &ktr_buf[tstate.cur]; 463 464 /* Skip over unused entries. */ 465 if (kp->ktr_desc == NULL) { 466 db_printf("--- End of trace buffer ---\n"); 467 return (0); 468 } 469 db_printf("%d (%p", tstate.cur, kp->ktr_thread); 470 #ifdef SMP 471 db_printf(":cpu%d", kp->ktr_cpu); 472 #endif 473 db_printf(")"); 474 if (db_ktr_verbose >= 1) { 475 db_printf(" %10.10lld", (long long)kp->ktr_timestamp); 476 } 477 if (db_ktr_verbose >= 2) { 478 db_printf(" %s.%d", kp->ktr_file, kp->ktr_line); 479 } 480 db_printf(": "); 481 db_printf(kp->ktr_desc, kp->ktr_parms[0], kp->ktr_parms[1], 482 kp->ktr_parms[2], kp->ktr_parms[3], kp->ktr_parms[4], 483 kp->ktr_parms[5]); 484 db_printf("\n"); 485 486 if (tstate.first == -1) 487 tstate.first = tstate.cur; 488 489 if (--tstate.cur < 0) 490 tstate.cur = ktr_entries - 1; 491 492 return (1); 493 } 494 495 #endif /* DDB */ 496