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 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 /* 28 * This module holds the global variables used by KTR and the ktr_tracepoint() 29 * function that does the actual tracing. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include "opt_ddb.h" 36 #include "opt_ktr.h" 37 #include "opt_alq.h" 38 39 #include <sys/param.h> 40 #include <sys/queue.h> 41 #include <sys/alq.h> 42 #include <sys/cons.h> 43 #include <sys/cpuset.h> 44 #include <sys/kdb.h> 45 #include <sys/kernel.h> 46 #include <sys/ktr.h> 47 #include <sys/libkern.h> 48 #include <sys/lock.h> 49 #include <sys/malloc.h> 50 #include <sys/mutex.h> 51 #include <sys/proc.h> 52 #include <sys/smp.h> 53 #include <sys/sysctl.h> 54 #include <sys/systm.h> 55 #include <sys/time.h> 56 57 #include <machine/cpu.h> 58 #ifdef __sparc64__ 59 #include <machine/ktr.h> 60 #endif 61 62 #ifdef DDB 63 #include <ddb/ddb.h> 64 #include <ddb/db_output.h> 65 #endif 66 67 #ifndef KTR_BOOT_ENTRIES 68 #define KTR_BOOT_ENTRIES 1024 69 #endif 70 71 #ifndef KTR_ENTRIES 72 #define KTR_ENTRIES 1024 73 #endif 74 75 /* Limit the allocations to something manageable. */ 76 #define KTR_ENTRIES_MAX (8 * 1024 * 1024) 77 78 #ifndef KTR_MASK 79 #define KTR_MASK (0) 80 #endif 81 82 #ifndef KTR_CPUMASK 83 #define KTR_CPUMASK CPUSET_FSET 84 #endif 85 86 #ifndef KTR_TIME 87 #define KTR_TIME get_cyclecount() 88 #endif 89 90 #ifndef KTR_CPU 91 #define KTR_CPU PCPU_GET(cpuid) 92 #endif 93 94 static MALLOC_DEFINE(M_KTR, "KTR", "KTR"); 95 96 FEATURE(ktr, "Kernel support for KTR kernel tracing facility"); 97 98 volatile int ktr_idx = 0; 99 uint64_t ktr_mask = KTR_MASK; 100 uint64_t ktr_compile = KTR_COMPILE; 101 int ktr_entries = KTR_BOOT_ENTRIES; 102 int ktr_version = KTR_VERSION; 103 struct ktr_entry ktr_buf_init[KTR_BOOT_ENTRIES]; 104 struct ktr_entry *ktr_buf = ktr_buf_init; 105 cpuset_t ktr_cpumask = CPUSET_T_INITIALIZER(KTR_CPUMASK); 106 107 static SYSCTL_NODE(_debug, OID_AUTO, ktr, CTLFLAG_RD, 0, "KTR options"); 108 109 SYSCTL_INT(_debug_ktr, OID_AUTO, version, CTLFLAG_RD, 110 &ktr_version, 0, "Version of the KTR interface"); 111 112 SYSCTL_UQUAD(_debug_ktr, OID_AUTO, compile, CTLFLAG_RD, 113 &ktr_compile, 0, "Bitmask of KTR event classes compiled into the kernel"); 114 115 static int 116 sysctl_debug_ktr_cpumask(SYSCTL_HANDLER_ARGS) 117 { 118 char lktr_cpumask_str[CPUSETBUFSIZ]; 119 cpuset_t imask; 120 int error; 121 122 cpusetobj_strprint(lktr_cpumask_str, &ktr_cpumask); 123 error = sysctl_handle_string(oidp, lktr_cpumask_str, 124 sizeof(lktr_cpumask_str), req); 125 if (error != 0 || req->newptr == NULL) 126 return (error); 127 if (cpusetobj_strscan(&imask, lktr_cpumask_str) == -1) 128 return (EINVAL); 129 CPU_COPY(&imask, &ktr_cpumask); 130 131 return (error); 132 } 133 SYSCTL_PROC(_debug_ktr, OID_AUTO, cpumask, 134 CTLFLAG_RWTUN | CTLFLAG_MPSAFE | CTLTYPE_STRING, NULL, 0, 135 sysctl_debug_ktr_cpumask, "S", 136 "Bitmask of CPUs on which KTR logging is enabled"); 137 138 static int 139 sysctl_debug_ktr_clear(SYSCTL_HANDLER_ARGS) 140 { 141 int clear, error; 142 143 clear = 0; 144 error = sysctl_handle_int(oidp, &clear, 0, req); 145 if (error || !req->newptr) 146 return (error); 147 148 if (clear) { 149 bzero(ktr_buf, sizeof(*ktr_buf) * ktr_entries); 150 ktr_idx = 0; 151 } 152 153 return (error); 154 } 155 SYSCTL_PROC(_debug_ktr, OID_AUTO, clear, CTLTYPE_INT|CTLFLAG_RW, 0, 0, 156 sysctl_debug_ktr_clear, "I", "Clear KTR Buffer"); 157 158 /* 159 * This is a sysctl proc so that it is serialized as !MPSAFE along with 160 * the other ktr sysctl procs. 161 */ 162 static int 163 sysctl_debug_ktr_mask(SYSCTL_HANDLER_ARGS) 164 { 165 uint64_t mask; 166 int error; 167 168 mask = ktr_mask; 169 error = sysctl_handle_64(oidp, &mask, 0, req); 170 if (error || !req->newptr) 171 return (error); 172 ktr_mask = mask; 173 return (error); 174 } 175 176 SYSCTL_PROC(_debug_ktr, OID_AUTO, mask, CTLTYPE_U64 | CTLFLAG_RWTUN, 0, 0, 177 sysctl_debug_ktr_mask, "QU", 178 "Bitmask of KTR event classes for which logging is enabled"); 179 180 #if KTR_ENTRIES > KTR_BOOT_ENTRIES 181 /* 182 * A simplified version of sysctl_debug_ktr_entries. 183 * No need to care about SMP, scheduling, etc. 184 */ 185 static void 186 ktr_entries_initializer(void *dummy __unused) 187 { 188 uint64_t mask; 189 190 /* Temporarily disable ktr in case malloc() is being traced. */ 191 mask = ktr_mask; 192 ktr_mask = 0; 193 ktr_buf = malloc(sizeof(*ktr_buf) * KTR_ENTRIES, M_KTR, 194 M_WAITOK | M_ZERO); 195 memcpy(ktr_buf, ktr_buf_init + ktr_idx, 196 (KTR_BOOT_ENTRIES - ktr_idx) * sizeof(*ktr_buf)); 197 if (ktr_idx != 0) { 198 memcpy(ktr_buf + KTR_BOOT_ENTRIES - ktr_idx, ktr_buf_init, 199 ktr_idx * sizeof(*ktr_buf)); 200 ktr_idx = KTR_BOOT_ENTRIES; 201 } 202 ktr_entries = KTR_ENTRIES; 203 ktr_mask = mask; 204 } 205 SYSINIT(ktr_entries_initializer, SI_SUB_KMEM, SI_ORDER_ANY, 206 ktr_entries_initializer, NULL); 207 #endif 208 209 static int 210 sysctl_debug_ktr_entries(SYSCTL_HANDLER_ARGS) 211 { 212 uint64_t mask; 213 int entries, error; 214 struct ktr_entry *buf, *oldbuf; 215 216 entries = ktr_entries; 217 error = sysctl_handle_int(oidp, &entries, 0, req); 218 if (error || !req->newptr) 219 return (error); 220 if (entries > KTR_ENTRIES_MAX) 221 return (ERANGE); 222 /* Disable ktr temporarily. */ 223 mask = ktr_mask; 224 ktr_mask = 0; 225 /* Wait for threads to go idle. */ 226 if ((error = quiesce_all_cpus("ktrent", PCATCH)) != 0) { 227 ktr_mask = mask; 228 return (error); 229 } 230 if (ktr_buf != ktr_buf_init) 231 oldbuf = ktr_buf; 232 else 233 oldbuf = NULL; 234 /* Allocate a new buffer. */ 235 buf = malloc(sizeof(*buf) * entries, M_KTR, M_WAITOK | M_ZERO); 236 /* Install the new buffer and restart ktr. */ 237 ktr_buf = buf; 238 ktr_entries = entries; 239 ktr_idx = 0; 240 ktr_mask = mask; 241 if (oldbuf != NULL) 242 free(oldbuf, M_KTR); 243 244 return (error); 245 } 246 247 SYSCTL_PROC(_debug_ktr, OID_AUTO, entries, CTLTYPE_INT|CTLFLAG_RW, 0, 0, 248 sysctl_debug_ktr_entries, "I", "Number of entries in the KTR buffer"); 249 250 #ifdef KTR_VERBOSE 251 int ktr_verbose = KTR_VERBOSE; 252 TUNABLE_INT("debug.ktr.verbose", &ktr_verbose); 253 SYSCTL_INT(_debug_ktr, OID_AUTO, verbose, CTLFLAG_RW, &ktr_verbose, 0, ""); 254 #endif 255 256 #ifdef KTR_ALQ 257 struct alq *ktr_alq; 258 char ktr_alq_file[MAXPATHLEN] = "/tmp/ktr.out"; 259 int ktr_alq_cnt = 0; 260 int ktr_alq_depth = KTR_ENTRIES; 261 int ktr_alq_enabled = 0; 262 int ktr_alq_failed = 0; 263 int ktr_alq_max = 0; 264 265 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_max, CTLFLAG_RW, &ktr_alq_max, 0, 266 "Maximum number of entries to write"); 267 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_cnt, CTLFLAG_RD, &ktr_alq_cnt, 0, 268 "Current number of written entries"); 269 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_failed, CTLFLAG_RD, &ktr_alq_failed, 0, 270 "Number of times we overran the buffer"); 271 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_depth, CTLFLAG_RW, &ktr_alq_depth, 0, 272 "Number of items in the write buffer"); 273 SYSCTL_STRING(_debug_ktr, OID_AUTO, alq_file, CTLFLAG_RW, ktr_alq_file, 274 sizeof(ktr_alq_file), "KTR logging file"); 275 276 static int 277 sysctl_debug_ktr_alq_enable(SYSCTL_HANDLER_ARGS) 278 { 279 int error; 280 int enable; 281 282 enable = ktr_alq_enabled; 283 284 error = sysctl_handle_int(oidp, &enable, 0, req); 285 if (error || !req->newptr) 286 return (error); 287 288 if (enable) { 289 if (ktr_alq_enabled) 290 return (0); 291 error = alq_open(&ktr_alq, (const char *)ktr_alq_file, 292 req->td->td_ucred, ALQ_DEFAULT_CMODE, 293 sizeof(struct ktr_entry), ktr_alq_depth); 294 if (error == 0) { 295 ktr_alq_cnt = 0; 296 ktr_alq_failed = 0; 297 ktr_alq_enabled = 1; 298 } 299 } else { 300 if (ktr_alq_enabled == 0) 301 return (0); 302 ktr_alq_enabled = 0; 303 alq_close(ktr_alq); 304 ktr_alq = NULL; 305 } 306 307 return (error); 308 } 309 SYSCTL_PROC(_debug_ktr, OID_AUTO, alq_enable, 310 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_debug_ktr_alq_enable, 311 "I", "Enable KTR logging"); 312 #endif 313 314 void 315 ktr_tracepoint(uint64_t mask, const char *file, int line, const char *format, 316 u_long arg1, u_long arg2, u_long arg3, u_long arg4, u_long arg5, 317 u_long arg6) 318 { 319 struct ktr_entry *entry; 320 #ifdef KTR_ALQ 321 struct ale *ale = NULL; 322 #endif 323 int newindex, saveindex; 324 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 325 struct thread *td; 326 #endif 327 int cpu; 328 329 if (panicstr || kdb_active) 330 return; 331 if ((ktr_mask & mask) == 0 || ktr_buf == NULL) 332 return; 333 cpu = KTR_CPU; 334 if (!CPU_ISSET(cpu, &ktr_cpumask)) 335 return; 336 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 337 td = curthread; 338 if (td->td_pflags & TDP_INKTR) 339 return; 340 td->td_pflags |= TDP_INKTR; 341 #endif 342 #ifdef KTR_ALQ 343 if (ktr_alq_enabled) { 344 if (td->td_critnest == 0 && 345 (td->td_flags & TDF_IDLETD) == 0 && 346 td != ald_thread) { 347 if (ktr_alq_max && ktr_alq_cnt > ktr_alq_max) 348 goto done; 349 if ((ale = alq_get(ktr_alq, ALQ_NOWAIT)) == NULL) { 350 ktr_alq_failed++; 351 goto done; 352 } 353 ktr_alq_cnt++; 354 entry = (struct ktr_entry *)ale->ae_data; 355 } else { 356 goto done; 357 } 358 } else 359 #endif 360 { 361 do { 362 saveindex = ktr_idx; 363 newindex = (saveindex + 1) % ktr_entries; 364 } while (atomic_cmpset_rel_int(&ktr_idx, saveindex, newindex) == 0); 365 entry = &ktr_buf[saveindex]; 366 } 367 entry->ktr_timestamp = KTR_TIME; 368 entry->ktr_cpu = cpu; 369 entry->ktr_thread = curthread; 370 if (file != NULL) 371 while (strncmp(file, "../", 3) == 0) 372 file += 3; 373 entry->ktr_file = file; 374 entry->ktr_line = line; 375 #ifdef KTR_VERBOSE 376 if (ktr_verbose) { 377 #ifdef SMP 378 printf("cpu%d ", cpu); 379 #endif 380 if (ktr_verbose > 1) { 381 printf("%s.%d\t", entry->ktr_file, 382 entry->ktr_line); 383 } 384 printf(format, arg1, arg2, arg3, arg4, arg5, arg6); 385 printf("\n"); 386 } 387 #endif 388 entry->ktr_desc = format; 389 entry->ktr_parms[0] = arg1; 390 entry->ktr_parms[1] = arg2; 391 entry->ktr_parms[2] = arg3; 392 entry->ktr_parms[3] = arg4; 393 entry->ktr_parms[4] = arg5; 394 entry->ktr_parms[5] = arg6; 395 #ifdef KTR_ALQ 396 if (ktr_alq_enabled && ale) 397 alq_post(ktr_alq, ale); 398 done: 399 #endif 400 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 401 td->td_pflags &= ~TDP_INKTR; 402 #endif 403 } 404 405 #ifdef DDB 406 407 struct tstate { 408 int cur; 409 int first; 410 }; 411 static struct tstate tstate; 412 static int db_ktr_verbose; 413 static int db_mach_vtrace(void); 414 415 DB_SHOW_COMMAND(ktr, db_ktr_all) 416 { 417 418 tstate.cur = (ktr_idx - 1) % ktr_entries; 419 tstate.first = -1; 420 db_ktr_verbose = 0; 421 db_ktr_verbose |= (strchr(modif, 'v') != NULL) ? 2 : 0; 422 db_ktr_verbose |= (strchr(modif, 'V') != NULL) ? 1 : 0; /* just timestap please */ 423 if (strchr(modif, 'a') != NULL) { 424 db_disable_pager(); 425 while (cncheckc() != -1) 426 if (db_mach_vtrace() == 0) 427 break; 428 } else { 429 while (!db_pager_quit) 430 if (db_mach_vtrace() == 0) 431 break; 432 } 433 } 434 435 static int 436 db_mach_vtrace(void) 437 { 438 struct ktr_entry *kp; 439 440 if (tstate.cur == tstate.first || ktr_buf == NULL) { 441 db_printf("--- End of trace buffer ---\n"); 442 return (0); 443 } 444 kp = &ktr_buf[tstate.cur]; 445 446 /* Skip over unused entries. */ 447 if (kp->ktr_desc == NULL) { 448 db_printf("--- End of trace buffer ---\n"); 449 return (0); 450 } 451 db_printf("%d (%p", tstate.cur, kp->ktr_thread); 452 #ifdef SMP 453 db_printf(":cpu%d", kp->ktr_cpu); 454 #endif 455 db_printf(")"); 456 if (db_ktr_verbose >= 1) { 457 db_printf(" %10.10lld", (long long)kp->ktr_timestamp); 458 } 459 if (db_ktr_verbose >= 2) { 460 db_printf(" %s.%d", kp->ktr_file, kp->ktr_line); 461 } 462 db_printf(": "); 463 db_printf(kp->ktr_desc, kp->ktr_parms[0], kp->ktr_parms[1], 464 kp->ktr_parms[2], kp->ktr_parms[3], kp->ktr_parms[4], 465 kp->ktr_parms[5]); 466 db_printf("\n"); 467 468 if (tstate.first == -1) 469 tstate.first = tstate.cur; 470 471 if (--tstate.cur < 0) 472 tstate.cur = ktr_entries - 1; 473 474 return (1); 475 } 476 477 #endif /* DDB */ 478