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