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/proc.h> 51 #include <sys/sysctl.h> 52 #include <sys/systm.h> 53 #include <sys/time.h> 54 55 #include <machine/cpu.h> 56 #ifdef __sparc64__ 57 #include <machine/ktr.h> 58 #endif 59 60 #ifdef DDB 61 #include <ddb/ddb.h> 62 #include <ddb/db_output.h> 63 #endif 64 65 #ifndef KTR_ENTRIES 66 #define KTR_ENTRIES 1024 67 #endif 68 69 #ifndef KTR_MASK 70 #define KTR_MASK (0) 71 #endif 72 73 #ifndef KTR_CPUMASK 74 #define KTR_CPUMASK CPUSET_FSET 75 #endif 76 77 #ifndef KTR_TIME 78 #define KTR_TIME get_cyclecount() 79 #endif 80 81 #ifndef KTR_CPU 82 #define KTR_CPU PCPU_GET(cpuid) 83 #endif 84 85 FEATURE(ktr, "Kernel support for KTR kernel tracing facility"); 86 87 static SYSCTL_NODE(_debug, OID_AUTO, ktr, CTLFLAG_RD, 0, "KTR options"); 88 89 int ktr_mask = KTR_MASK; 90 TUNABLE_INT("debug.ktr.mask", &ktr_mask); 91 SYSCTL_INT(_debug_ktr, OID_AUTO, mask, CTLFLAG_RW, 92 &ktr_mask, 0, "Bitmask of KTR event classes for which logging is enabled"); 93 94 int ktr_compile = KTR_COMPILE; 95 SYSCTL_INT(_debug_ktr, OID_AUTO, compile, CTLFLAG_RD, 96 &ktr_compile, 0, "Bitmask of KTR event classes compiled into the kernel"); 97 98 int ktr_entries = KTR_ENTRIES; 99 SYSCTL_INT(_debug_ktr, OID_AUTO, entries, CTLFLAG_RD, 100 &ktr_entries, 0, "Number of entries in the KTR buffer"); 101 102 int ktr_version = KTR_VERSION; 103 SYSCTL_INT(_debug_ktr, OID_AUTO, version, CTLFLAG_RD, 104 &ktr_version, 0, "Version of the KTR interface"); 105 106 cpuset_t ktr_cpumask = CPUSET_T_INITIALIZER(KTR_CPUMASK); 107 static char ktr_cpumask_str[CPUSETBUFSIZ]; 108 TUNABLE_STR("debug.ktr.cpumask", ktr_cpumask_str, sizeof(ktr_cpumask_str)); 109 110 static void 111 ktr_cpumask_initializer(void *dummy __unused) 112 { 113 114 /* 115 * TUNABLE_STR() runs with SI_ORDER_MIDDLE priority, thus it must be 116 * already set, if necessary. 117 */ 118 if (ktr_cpumask_str[0] != '\0' && 119 cpusetobj_strscan(&ktr_cpumask, ktr_cpumask_str) == -1) 120 CPU_FILL(&ktr_cpumask); 121 } 122 SYSINIT(ktr_cpumask_initializer, SI_SUB_TUNABLES, SI_ORDER_ANY, 123 ktr_cpumask_initializer, NULL); 124 125 static int 126 sysctl_debug_ktr_cpumask(SYSCTL_HANDLER_ARGS) 127 { 128 char lktr_cpumask_str[CPUSETBUFSIZ]; 129 cpuset_t imask; 130 int error; 131 132 cpusetobj_strprint(lktr_cpumask_str, &ktr_cpumask); 133 error = sysctl_handle_string(oidp, lktr_cpumask_str, 134 sizeof(lktr_cpumask_str), req); 135 if (error != 0 || req->newptr == NULL) 136 return (error); 137 if (cpusetobj_strscan(&imask, lktr_cpumask_str) == -1) 138 return (EINVAL); 139 CPU_COPY(&imask, &ktr_cpumask); 140 141 return (error); 142 } 143 SYSCTL_PROC(_debug_ktr, OID_AUTO, cpumask, 144 CTLFLAG_RW | CTLFLAG_MPSAFE | CTLTYPE_STRING, NULL, 0, 145 sysctl_debug_ktr_cpumask, "S", 146 "Bitmask of CPUs on which KTR logging is enabled"); 147 148 volatile int ktr_idx = 0; 149 struct ktr_entry ktr_buf[KTR_ENTRIES]; 150 151 static int 152 sysctl_debug_ktr_clear(SYSCTL_HANDLER_ARGS) 153 { 154 int clear, error; 155 156 clear = 0; 157 error = sysctl_handle_int(oidp, &clear, 0, req); 158 if (error || !req->newptr) 159 return (error); 160 161 if (clear) { 162 bzero(ktr_buf, sizeof(ktr_buf)); 163 ktr_idx = 0; 164 } 165 166 return (error); 167 } 168 SYSCTL_PROC(_debug_ktr, OID_AUTO, clear, CTLTYPE_INT|CTLFLAG_RW, 0, 0, 169 sysctl_debug_ktr_clear, "I", "Clear KTR Buffer"); 170 171 #ifdef KTR_VERBOSE 172 int ktr_verbose = KTR_VERBOSE; 173 TUNABLE_INT("debug.ktr.verbose", &ktr_verbose); 174 SYSCTL_INT(_debug_ktr, OID_AUTO, verbose, CTLFLAG_RW, &ktr_verbose, 0, ""); 175 #endif 176 177 #ifdef KTR_ALQ 178 struct alq *ktr_alq; 179 char ktr_alq_file[MAXPATHLEN] = "/tmp/ktr.out"; 180 int ktr_alq_cnt = 0; 181 int ktr_alq_depth = KTR_ENTRIES; 182 int ktr_alq_enabled = 0; 183 int ktr_alq_failed = 0; 184 int ktr_alq_max = 0; 185 186 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_max, CTLFLAG_RW, &ktr_alq_max, 0, 187 "Maximum number of entries to write"); 188 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_cnt, CTLFLAG_RD, &ktr_alq_cnt, 0, 189 "Current number of written entries"); 190 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_failed, CTLFLAG_RD, &ktr_alq_failed, 0, 191 "Number of times we overran the buffer"); 192 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_depth, CTLFLAG_RW, &ktr_alq_depth, 0, 193 "Number of items in the write buffer"); 194 SYSCTL_STRING(_debug_ktr, OID_AUTO, alq_file, CTLFLAG_RW, ktr_alq_file, 195 sizeof(ktr_alq_file), "KTR logging file"); 196 197 static int 198 sysctl_debug_ktr_alq_enable(SYSCTL_HANDLER_ARGS) 199 { 200 int error; 201 int enable; 202 203 enable = ktr_alq_enabled; 204 205 error = sysctl_handle_int(oidp, &enable, 0, req); 206 if (error || !req->newptr) 207 return (error); 208 209 if (enable) { 210 if (ktr_alq_enabled) 211 return (0); 212 error = alq_open(&ktr_alq, (const char *)ktr_alq_file, 213 req->td->td_ucred, ALQ_DEFAULT_CMODE, 214 sizeof(struct ktr_entry), ktr_alq_depth); 215 if (error == 0) { 216 ktr_alq_cnt = 0; 217 ktr_alq_failed = 0; 218 ktr_alq_enabled = 1; 219 } 220 } else { 221 if (ktr_alq_enabled == 0) 222 return (0); 223 ktr_alq_enabled = 0; 224 alq_close(ktr_alq); 225 ktr_alq = NULL; 226 } 227 228 return (error); 229 } 230 SYSCTL_PROC(_debug_ktr, OID_AUTO, alq_enable, 231 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_debug_ktr_alq_enable, 232 "I", "Enable KTR logging"); 233 #endif 234 235 void 236 ktr_tracepoint(u_int mask, const char *file, int line, const char *format, 237 u_long arg1, u_long arg2, u_long arg3, u_long arg4, u_long arg5, 238 u_long arg6) 239 { 240 struct ktr_entry *entry; 241 #ifdef KTR_ALQ 242 struct ale *ale = NULL; 243 #endif 244 int newindex, saveindex; 245 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 246 struct thread *td; 247 #endif 248 int cpu; 249 250 if (panicstr) 251 return; 252 if ((ktr_mask & mask) == 0) 253 return; 254 cpu = KTR_CPU; 255 if (!CPU_ISSET(cpu, &ktr_cpumask)) 256 return; 257 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 258 td = curthread; 259 if (td->td_pflags & TDP_INKTR) 260 return; 261 td->td_pflags |= TDP_INKTR; 262 #endif 263 #ifdef KTR_ALQ 264 if (ktr_alq_enabled) { 265 if (td->td_critnest == 0 && 266 (td->td_flags & TDF_IDLETD) == 0 && 267 td != ald_thread) { 268 if (ktr_alq_max && ktr_alq_cnt > ktr_alq_max) 269 goto done; 270 if ((ale = alq_get(ktr_alq, ALQ_NOWAIT)) == NULL) { 271 ktr_alq_failed++; 272 goto done; 273 } 274 ktr_alq_cnt++; 275 entry = (struct ktr_entry *)ale->ae_data; 276 } else { 277 goto done; 278 } 279 } else 280 #endif 281 { 282 do { 283 saveindex = ktr_idx; 284 newindex = (saveindex + 1) % KTR_ENTRIES; 285 } while (atomic_cmpset_rel_int(&ktr_idx, saveindex, newindex) == 0); 286 entry = &ktr_buf[saveindex]; 287 } 288 entry->ktr_timestamp = KTR_TIME; 289 entry->ktr_cpu = cpu; 290 entry->ktr_thread = curthread; 291 if (file != NULL) 292 while (strncmp(file, "../", 3) == 0) 293 file += 3; 294 entry->ktr_file = file; 295 entry->ktr_line = line; 296 #ifdef KTR_VERBOSE 297 if (ktr_verbose) { 298 #ifdef SMP 299 printf("cpu%d ", cpu); 300 #endif 301 if (ktr_verbose > 1) { 302 printf("%s.%d\t", entry->ktr_file, 303 entry->ktr_line); 304 } 305 printf(format, arg1, arg2, arg3, arg4, arg5, arg6); 306 printf("\n"); 307 } 308 #endif 309 entry->ktr_desc = format; 310 entry->ktr_parms[0] = arg1; 311 entry->ktr_parms[1] = arg2; 312 entry->ktr_parms[2] = arg3; 313 entry->ktr_parms[3] = arg4; 314 entry->ktr_parms[4] = arg5; 315 entry->ktr_parms[5] = arg6; 316 #ifdef KTR_ALQ 317 if (ktr_alq_enabled && ale) 318 alq_post(ktr_alq, ale); 319 done: 320 #endif 321 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 322 td->td_pflags &= ~TDP_INKTR; 323 #endif 324 } 325 326 #ifdef DDB 327 328 struct tstate { 329 int cur; 330 int first; 331 }; 332 static struct tstate tstate; 333 static int db_ktr_verbose; 334 static int db_mach_vtrace(void); 335 336 DB_SHOW_COMMAND(ktr, db_ktr_all) 337 { 338 339 tstate.cur = (ktr_idx - 1) % KTR_ENTRIES; 340 tstate.first = -1; 341 db_ktr_verbose = 0; 342 db_ktr_verbose |= (strchr(modif, 'v') != NULL) ? 2 : 0; 343 db_ktr_verbose |= (strchr(modif, 'V') != NULL) ? 1 : 0; /* just timestap please */ 344 if (strchr(modif, 'a') != NULL) { 345 db_disable_pager(); 346 while (cncheckc() != -1) 347 if (db_mach_vtrace() == 0) 348 break; 349 } else { 350 while (!db_pager_quit) 351 if (db_mach_vtrace() == 0) 352 break; 353 } 354 } 355 356 static int 357 db_mach_vtrace(void) 358 { 359 struct ktr_entry *kp; 360 361 if (tstate.cur == tstate.first) { 362 db_printf("--- End of trace buffer ---\n"); 363 return (0); 364 } 365 kp = &ktr_buf[tstate.cur]; 366 367 /* Skip over unused entries. */ 368 if (kp->ktr_desc == NULL) { 369 db_printf("--- End of trace buffer ---\n"); 370 return (0); 371 } 372 db_printf("%d (%p", tstate.cur, kp->ktr_thread); 373 #ifdef SMP 374 db_printf(":cpu%d", kp->ktr_cpu); 375 #endif 376 db_printf(")"); 377 if (db_ktr_verbose >= 1) { 378 db_printf(" %10.10lld", (long long)kp->ktr_timestamp); 379 } 380 if (db_ktr_verbose >= 2) { 381 db_printf(" %s.%d", kp->ktr_file, kp->ktr_line); 382 } 383 db_printf(": "); 384 db_printf(kp->ktr_desc, kp->ktr_parms[0], kp->ktr_parms[1], 385 kp->ktr_parms[2], kp->ktr_parms[3], kp->ktr_parms[4], 386 kp->ktr_parms[5]); 387 db_printf("\n"); 388 389 if (tstate.first == -1) 390 tstate.first = tstate.cur; 391 392 if (--tstate.cur < 0) 393 tstate.cur = KTR_ENTRIES - 1; 394 395 return (1); 396 } 397 398 #endif /* DDB */ 399