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/alq.h> 44 #include <sys/cons.h> 45 #include <sys/kernel.h> 46 #include <sys/ktr.h> 47 #include <sys/libkern.h> 48 #include <sys/proc.h> 49 #include <sys/sysctl.h> 50 #include <sys/systm.h> 51 #include <sys/time.h> 52 53 #include <machine/cpu.h> 54 #ifdef __sparc64__ 55 #include <machine/ktr.h> 56 #endif 57 58 #ifdef DDB 59 #include <ddb/ddb.h> 60 #include <ddb/db_output.h> 61 #endif 62 63 #ifndef KTR_ENTRIES 64 #define KTR_ENTRIES 1024 65 #endif 66 67 #ifndef KTR_MASK 68 #define KTR_MASK (0) 69 #endif 70 71 #ifndef KTR_CPUMASK 72 #define KTR_CPUMASK (~0) 73 #endif 74 75 #ifndef KTR_TIME 76 #define KTR_TIME get_cyclecount() 77 #endif 78 79 #ifndef KTR_CPU 80 #define KTR_CPU PCPU_GET(cpuid) 81 #endif 82 83 FEATURE(ktr, "Kernel support for KTR kernel tracing facility"); 84 85 SYSCTL_NODE(_debug, OID_AUTO, ktr, CTLFLAG_RD, 0, "KTR options"); 86 87 int ktr_cpumask = KTR_CPUMASK; 88 TUNABLE_INT("debug.ktr.cpumask", &ktr_cpumask); 89 SYSCTL_INT(_debug_ktr, OID_AUTO, cpumask, CTLFLAG_RW, 90 &ktr_cpumask, 0, "Bitmask of CPUs on which KTR logging is enabled"); 91 92 int ktr_mask = KTR_MASK; 93 TUNABLE_INT("debug.ktr.mask", &ktr_mask); 94 SYSCTL_INT(_debug_ktr, OID_AUTO, mask, CTLFLAG_RW, 95 &ktr_mask, 0, "Bitmask of KTR event classes for which logging is enabled"); 96 97 int ktr_compile = KTR_COMPILE; 98 SYSCTL_INT(_debug_ktr, OID_AUTO, compile, CTLFLAG_RD, 99 &ktr_compile, 0, "Bitmask of KTR event classes compiled into the kernel"); 100 101 int ktr_entries = KTR_ENTRIES; 102 SYSCTL_INT(_debug_ktr, OID_AUTO, entries, CTLFLAG_RD, 103 &ktr_entries, 0, "Number of entries in the KTR buffer"); 104 105 int ktr_version = KTR_VERSION; 106 SYSCTL_INT(_debug_ktr, OID_AUTO, version, CTLFLAG_RD, 107 &ktr_version, 0, "Version of the KTR interface"); 108 109 volatile int ktr_idx = 0; 110 struct ktr_entry ktr_buf[KTR_ENTRIES]; 111 112 static int 113 sysctl_debug_ktr_clear(SYSCTL_HANDLER_ARGS) 114 { 115 int clear, error; 116 117 clear = 0; 118 error = sysctl_handle_int(oidp, &clear, 0, req); 119 if (error || !req->newptr) 120 return (error); 121 122 if (clear) { 123 bzero(ktr_buf, sizeof(ktr_buf)); 124 ktr_idx = 0; 125 } 126 127 return (error); 128 } 129 SYSCTL_PROC(_debug_ktr, OID_AUTO, clear, CTLTYPE_INT|CTLFLAG_RW, 0, 0, 130 sysctl_debug_ktr_clear, "I", "Clear KTR Buffer"); 131 132 #ifdef KTR_VERBOSE 133 int ktr_verbose = KTR_VERBOSE; 134 TUNABLE_INT("debug.ktr.verbose", &ktr_verbose); 135 SYSCTL_INT(_debug_ktr, OID_AUTO, verbose, CTLFLAG_RW, &ktr_verbose, 0, ""); 136 #endif 137 138 #ifdef KTR_ALQ 139 struct alq *ktr_alq; 140 char ktr_alq_file[MAXPATHLEN] = "/tmp/ktr.out"; 141 int ktr_alq_cnt = 0; 142 int ktr_alq_depth = KTR_ENTRIES; 143 int ktr_alq_enabled = 0; 144 int ktr_alq_failed = 0; 145 int ktr_alq_max = 0; 146 147 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_max, CTLFLAG_RW, &ktr_alq_max, 0, 148 "Maximum number of entries to write"); 149 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_cnt, CTLFLAG_RD, &ktr_alq_cnt, 0, 150 "Current number of written entries"); 151 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_failed, CTLFLAG_RD, &ktr_alq_failed, 0, 152 "Number of times we overran the buffer"); 153 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_depth, CTLFLAG_RW, &ktr_alq_depth, 0, 154 "Number of items in the write buffer"); 155 SYSCTL_STRING(_debug_ktr, OID_AUTO, alq_file, CTLFLAG_RW, ktr_alq_file, 156 sizeof(ktr_alq_file), "KTR logging file"); 157 158 static int 159 sysctl_debug_ktr_alq_enable(SYSCTL_HANDLER_ARGS) 160 { 161 int error; 162 int enable; 163 164 enable = ktr_alq_enabled; 165 166 error = sysctl_handle_int(oidp, &enable, 0, req); 167 if (error || !req->newptr) 168 return (error); 169 170 if (enable) { 171 if (ktr_alq_enabled) 172 return (0); 173 error = alq_open(&ktr_alq, (const char *)ktr_alq_file, 174 req->td->td_ucred, ALQ_DEFAULT_CMODE, 175 sizeof(struct ktr_entry), ktr_alq_depth); 176 if (error == 0) { 177 ktr_alq_cnt = 0; 178 ktr_alq_failed = 0; 179 ktr_alq_enabled = 1; 180 } 181 } else { 182 if (ktr_alq_enabled == 0) 183 return (0); 184 ktr_alq_enabled = 0; 185 alq_close(ktr_alq); 186 ktr_alq = NULL; 187 } 188 189 return (error); 190 } 191 SYSCTL_PROC(_debug_ktr, OID_AUTO, alq_enable, 192 CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_debug_ktr_alq_enable, 193 "I", "Enable KTR logging"); 194 #endif 195 196 void 197 ktr_tracepoint(u_int mask, const char *file, int line, const char *format, 198 u_long arg1, u_long arg2, u_long arg3, u_long arg4, u_long arg5, 199 u_long arg6) 200 { 201 struct ktr_entry *entry; 202 #ifdef KTR_ALQ 203 struct ale *ale = NULL; 204 #endif 205 int newindex, saveindex; 206 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 207 struct thread *td; 208 #endif 209 int cpu; 210 211 if (panicstr) 212 return; 213 if ((ktr_mask & mask) == 0) 214 return; 215 cpu = KTR_CPU; 216 if (((1 << cpu) & ktr_cpumask) == 0) 217 return; 218 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 219 td = curthread; 220 if (td->td_pflags & TDP_INKTR) 221 return; 222 td->td_pflags |= TDP_INKTR; 223 #endif 224 #ifdef KTR_ALQ 225 if (ktr_alq_enabled) { 226 if (td->td_critnest == 0 && 227 (td->td_flags & TDF_IDLETD) == 0 && 228 td != ald_thread) { 229 if (ktr_alq_max && ktr_alq_cnt > ktr_alq_max) 230 goto done; 231 if ((ale = alq_get(ktr_alq, ALQ_NOWAIT)) == NULL) { 232 ktr_alq_failed++; 233 goto done; 234 } 235 ktr_alq_cnt++; 236 entry = (struct ktr_entry *)ale->ae_data; 237 } else { 238 goto done; 239 } 240 } else 241 #endif 242 { 243 do { 244 saveindex = ktr_idx; 245 newindex = (saveindex + 1) & (KTR_ENTRIES - 1); 246 } while (atomic_cmpset_rel_int(&ktr_idx, saveindex, newindex) == 0); 247 entry = &ktr_buf[saveindex]; 248 } 249 entry->ktr_timestamp = KTR_TIME; 250 entry->ktr_cpu = cpu; 251 entry->ktr_thread = curthread; 252 if (file != NULL) 253 while (strncmp(file, "../", 3) == 0) 254 file += 3; 255 entry->ktr_file = file; 256 entry->ktr_line = line; 257 #ifdef KTR_VERBOSE 258 if (ktr_verbose) { 259 #ifdef SMP 260 printf("cpu%d ", cpu); 261 #endif 262 if (ktr_verbose > 1) { 263 printf("%s.%d\t", entry->ktr_file, 264 entry->ktr_line); 265 } 266 printf(format, arg1, arg2, arg3, arg4, arg5, arg6); 267 printf("\n"); 268 } 269 #endif 270 entry->ktr_desc = format; 271 entry->ktr_parms[0] = arg1; 272 entry->ktr_parms[1] = arg2; 273 entry->ktr_parms[2] = arg3; 274 entry->ktr_parms[3] = arg4; 275 entry->ktr_parms[4] = arg5; 276 entry->ktr_parms[5] = arg6; 277 #ifdef KTR_ALQ 278 if (ktr_alq_enabled && ale) 279 alq_post(ktr_alq, ale); 280 done: 281 #endif 282 #if defined(KTR_VERBOSE) || defined(KTR_ALQ) 283 td->td_pflags &= ~TDP_INKTR; 284 #endif 285 } 286 287 #ifdef DDB 288 289 struct tstate { 290 int cur; 291 int first; 292 }; 293 static struct tstate tstate; 294 static int db_ktr_verbose; 295 static int db_mach_vtrace(void); 296 297 DB_SHOW_COMMAND(ktr, db_ktr_all) 298 { 299 300 tstate.cur = (ktr_idx - 1) & (KTR_ENTRIES - 1); 301 tstate.first = -1; 302 db_ktr_verbose = 0; 303 db_ktr_verbose |= (index(modif, 'v') != NULL) ? 2 : 0; 304 db_ktr_verbose |= (index(modif, 'V') != NULL) ? 1 : 0; /* just timestap please */ 305 if (index(modif, 'a') != NULL) { 306 db_disable_pager(); 307 while (cncheckc() != -1) 308 if (db_mach_vtrace() == 0) 309 break; 310 } else { 311 while (!db_pager_quit) 312 if (db_mach_vtrace() == 0) 313 break; 314 } 315 } 316 317 static int 318 db_mach_vtrace(void) 319 { 320 struct ktr_entry *kp; 321 322 if (tstate.cur == tstate.first) { 323 db_printf("--- End of trace buffer ---\n"); 324 return (0); 325 } 326 kp = &ktr_buf[tstate.cur]; 327 328 /* Skip over unused entries. */ 329 if (kp->ktr_desc == NULL) { 330 db_printf("--- End of trace buffer ---\n"); 331 return (0); 332 } 333 db_printf("%d (%p", tstate.cur, kp->ktr_thread); 334 #ifdef SMP 335 db_printf(":cpu%d", kp->ktr_cpu); 336 #endif 337 db_printf(")"); 338 if (db_ktr_verbose >= 1) { 339 db_printf(" %10.10lld", (long long)kp->ktr_timestamp); 340 } 341 if (db_ktr_verbose >= 2) { 342 db_printf(" %s.%d", kp->ktr_file, kp->ktr_line); 343 } 344 db_printf(": "); 345 db_printf(kp->ktr_desc, kp->ktr_parms[0], kp->ktr_parms[1], 346 kp->ktr_parms[2], kp->ktr_parms[3], kp->ktr_parms[4], 347 kp->ktr_parms[5]); 348 db_printf("\n"); 349 350 if (tstate.first == -1) 351 tstate.first = tstate.cur; 352 353 if (--tstate.cur < 0) 354 tstate.cur = KTR_ENTRIES - 1; 355 356 return (1); 357 } 358 359 #endif /* DDB */ 360