1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 * 21 * Portions Copyright 2006-2008 John Birrell jb@freebsd.org 22 * 23 * $FreeBSD$ 24 * 25 */ 26 27 /* 28 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 29 * Use is subject to license terms. 30 */ 31 32 #include <sys/cdefs.h> 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/conf.h> 36 #include <sys/cpuvar.h> 37 #include <sys/fcntl.h> 38 #include <sys/filio.h> 39 #include <sys/kdb.h> 40 #include <sys/kernel.h> 41 #include <sys/kmem.h> 42 #include <sys/kthread.h> 43 #include <sys/limits.h> 44 #include <sys/linker.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/module.h> 48 #include <sys/mutex.h> 49 #include <sys/poll.h> 50 #include <sys/proc.h> 51 #include <sys/selinfo.h> 52 #include <sys/smp.h> 53 #include <sys/uio.h> 54 #include <sys/unistd.h> 55 #include <machine/stdarg.h> 56 57 #include <sys/cyclic.h> 58 #include <sys/dtrace.h> 59 #include <sys/dtrace_bsd.h> 60 61 #define PROF_NAMELEN 15 62 63 #define PROF_PROFILE 0 64 #define PROF_TICK 1 65 #define PROF_PREFIX_PROFILE "profile-" 66 #define PROF_PREFIX_TICK "tick-" 67 68 /* 69 * Regardless of platform, there are five artificial frames in the case of the 70 * profile provider: 71 * 72 * profile_fire 73 * cyclic_expire 74 * cyclic_fire 75 * [ cbe ] 76 * [ locore ] 77 * 78 * On amd64, there are two frames associated with locore: one in locore, and 79 * another in common interrupt dispatch code. (i386 has not been modified to 80 * use this common layer.) Further, on i386, the interrupted instruction 81 * appears as its own stack frame. All of this means that we need to add one 82 * frame for amd64, and then take one away for both amd64 and i386. 83 * 84 * On SPARC, the picture is further complicated because the compiler 85 * optimizes away tail-calls -- so the following frames are optimized away: 86 * 87 * profile_fire 88 * cyclic_expire 89 * 90 * This gives three frames. However, on DEBUG kernels, the cyclic_expire 91 * frame cannot be tail-call eliminated, yielding four frames in this case. 92 * 93 * All of the above constraints lead to the mess below. Yes, the profile 94 * provider should ideally figure this out on-the-fly by hiting one of its own 95 * probes and then walking its own stack trace. This is complicated, however, 96 * and the static definition doesn't seem to be overly brittle. Still, we 97 * allow for a manual override in case we get it completely wrong. 98 */ 99 #ifdef __amd64 100 #define PROF_ARTIFICIAL_FRAMES 7 101 #else 102 #ifdef __i386 103 #define PROF_ARTIFICIAL_FRAMES 6 104 #else 105 #ifdef __sparc 106 #ifdef DEBUG 107 #define PROF_ARTIFICIAL_FRAMES 4 108 #else 109 #define PROF_ARTIFICIAL_FRAMES 3 110 #endif 111 #endif 112 #endif 113 #endif 114 115 #ifdef __mips 116 /* 117 * This value is bogus just to make module compilable on mips 118 */ 119 #define PROF_ARTIFICIAL_FRAMES 3 120 #endif 121 122 #ifdef __powerpc__ 123 /* 124 * This value is bogus just to make module compilable on powerpc 125 */ 126 #define PROF_ARTIFICIAL_FRAMES 3 127 #endif 128 129 typedef struct profile_probe { 130 char prof_name[PROF_NAMELEN]; 131 dtrace_id_t prof_id; 132 int prof_kind; 133 hrtime_t prof_interval; 134 cyclic_id_t prof_cyclic; 135 } profile_probe_t; 136 137 typedef struct profile_probe_percpu { 138 hrtime_t profc_expected; 139 hrtime_t profc_interval; 140 profile_probe_t *profc_probe; 141 } profile_probe_percpu_t; 142 143 static d_open_t profile_open; 144 static int profile_unload(void); 145 static void profile_create(hrtime_t, char *, int); 146 static void profile_destroy(void *, dtrace_id_t, void *); 147 static void profile_enable(void *, dtrace_id_t, void *); 148 static void profile_disable(void *, dtrace_id_t, void *); 149 static void profile_load(void *); 150 static void profile_provide(void *, dtrace_probedesc_t *); 151 152 static int profile_rates[] = { 153 97, 199, 499, 997, 1999, 154 4001, 4999, 0, 0, 0, 155 0, 0, 0, 0, 0, 156 0, 0, 0, 0, 0 157 }; 158 159 static int profile_ticks[] = { 160 1, 10, 100, 500, 1000, 161 5000, 0, 0, 0, 0, 162 0, 0, 0, 0, 0 163 }; 164 165 /* 166 * profile_max defines the upper bound on the number of profile probes that 167 * can exist (this is to prevent malicious or clumsy users from exhausing 168 * system resources by creating a slew of profile probes). At mod load time, 169 * this gets its value from PROFILE_MAX_DEFAULT or profile-max-probes if it's 170 * present in the profile.conf file. 171 */ 172 #define PROFILE_MAX_DEFAULT 1000 /* default max. number of probes */ 173 static uint32_t profile_max = PROFILE_MAX_DEFAULT; 174 /* maximum number of profile probes */ 175 static uint32_t profile_total; /* current number of profile probes */ 176 177 static struct cdevsw profile_cdevsw = { 178 .d_version = D_VERSION, 179 .d_open = profile_open, 180 .d_name = "profile", 181 }; 182 183 static dtrace_pattr_t profile_attr = { 184 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 185 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 186 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 187 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 188 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 189 }; 190 191 static dtrace_pops_t profile_pops = { 192 profile_provide, 193 NULL, 194 profile_enable, 195 profile_disable, 196 NULL, 197 NULL, 198 NULL, 199 NULL, 200 NULL, 201 profile_destroy 202 }; 203 204 static struct cdev *profile_cdev; 205 static dtrace_provider_id_t profile_id; 206 static hrtime_t profile_interval_min = NANOSEC / 5000; /* 5000 hz */ 207 static int profile_aframes = 0; /* override */ 208 209 static void 210 profile_fire(void *arg) 211 { 212 profile_probe_percpu_t *pcpu = arg; 213 profile_probe_t *prof = pcpu->profc_probe; 214 hrtime_t late; 215 solaris_cpu_t *c = &solaris_cpu[curcpu]; 216 217 late = gethrtime() - pcpu->profc_expected; 218 pcpu->profc_expected += pcpu->profc_interval; 219 220 dtrace_probe(prof->prof_id, c->cpu_profile_pc, 221 c->cpu_profile_upc, late, 0, 0); 222 } 223 224 static void 225 profile_tick(void *arg) 226 { 227 profile_probe_t *prof = arg; 228 solaris_cpu_t *c = &solaris_cpu[curcpu]; 229 230 dtrace_probe(prof->prof_id, c->cpu_profile_pc, 231 c->cpu_profile_upc, 0, 0, 0); 232 } 233 234 static void 235 profile_create(hrtime_t interval, char *name, int kind) 236 { 237 profile_probe_t *prof; 238 239 if (interval < profile_interval_min) 240 return; 241 242 if (dtrace_probe_lookup(profile_id, NULL, NULL, name) != 0) 243 return; 244 245 atomic_add_32(&profile_total, 1); 246 if (profile_total > profile_max) { 247 atomic_add_32(&profile_total, -1); 248 return; 249 } 250 251 prof = kmem_zalloc(sizeof (profile_probe_t), KM_SLEEP); 252 (void) strcpy(prof->prof_name, name); 253 prof->prof_interval = interval; 254 prof->prof_cyclic = CYCLIC_NONE; 255 prof->prof_kind = kind; 256 prof->prof_id = dtrace_probe_create(profile_id, 257 NULL, NULL, name, 258 profile_aframes ? profile_aframes : PROF_ARTIFICIAL_FRAMES, prof); 259 } 260 261 /*ARGSUSED*/ 262 static void 263 profile_provide(void *arg, dtrace_probedesc_t *desc) 264 { 265 int i, j, rate, kind; 266 hrtime_t val = 0, mult = 1, len = 0; 267 char *name, *suffix = NULL; 268 269 const struct { 270 char *prefix; 271 int kind; 272 } types[] = { 273 { PROF_PREFIX_PROFILE, PROF_PROFILE }, 274 { PROF_PREFIX_TICK, PROF_TICK }, 275 { 0, 0 } 276 }; 277 278 const struct { 279 char *name; 280 hrtime_t mult; 281 } suffixes[] = { 282 { "ns", NANOSEC / NANOSEC }, 283 { "nsec", NANOSEC / NANOSEC }, 284 { "us", NANOSEC / MICROSEC }, 285 { "usec", NANOSEC / MICROSEC }, 286 { "ms", NANOSEC / MILLISEC }, 287 { "msec", NANOSEC / MILLISEC }, 288 { "s", NANOSEC / SEC }, 289 { "sec", NANOSEC / SEC }, 290 { "m", NANOSEC * (hrtime_t)60 }, 291 { "min", NANOSEC * (hrtime_t)60 }, 292 { "h", NANOSEC * (hrtime_t)(60 * 60) }, 293 { "hour", NANOSEC * (hrtime_t)(60 * 60) }, 294 { "d", NANOSEC * (hrtime_t)(24 * 60 * 60) }, 295 { "day", NANOSEC * (hrtime_t)(24 * 60 * 60) }, 296 { "hz", 0 }, 297 { NULL } 298 }; 299 300 if (desc == NULL) { 301 char n[PROF_NAMELEN]; 302 303 /* 304 * If no description was provided, provide all of our probes. 305 */ 306 for (i = 0; i < sizeof (profile_rates) / sizeof (int); i++) { 307 if ((rate = profile_rates[i]) == 0) 308 continue; 309 310 (void) snprintf(n, PROF_NAMELEN, "%s%d", 311 PROF_PREFIX_PROFILE, rate); 312 profile_create(NANOSEC / rate, n, PROF_PROFILE); 313 } 314 315 for (i = 0; i < sizeof (profile_ticks) / sizeof (int); i++) { 316 if ((rate = profile_ticks[i]) == 0) 317 continue; 318 319 (void) snprintf(n, PROF_NAMELEN, "%s%d", 320 PROF_PREFIX_TICK, rate); 321 profile_create(NANOSEC / rate, n, PROF_TICK); 322 } 323 324 return; 325 } 326 327 name = desc->dtpd_name; 328 329 for (i = 0; types[i].prefix != NULL; i++) { 330 len = strlen(types[i].prefix); 331 332 if (strncmp(name, types[i].prefix, len) != 0) 333 continue; 334 break; 335 } 336 337 if (types[i].prefix == NULL) 338 return; 339 340 kind = types[i].kind; 341 j = strlen(name) - len; 342 343 /* 344 * We need to start before any time suffix. 345 */ 346 for (j = strlen(name); j >= len; j--) { 347 if (name[j] >= '0' && name[j] <= '9') 348 break; 349 suffix = &name[j]; 350 } 351 352 ASSERT(suffix != NULL); 353 354 /* 355 * Now determine the numerical value present in the probe name. 356 */ 357 for (; j >= len; j--) { 358 if (name[j] < '0' || name[j] > '9') 359 return; 360 361 val += (name[j] - '0') * mult; 362 mult *= (hrtime_t)10; 363 } 364 365 if (val == 0) 366 return; 367 368 /* 369 * Look-up the suffix to determine the multiplier. 370 */ 371 for (i = 0, mult = 0; suffixes[i].name != NULL; i++) { 372 if (strcasecmp(suffixes[i].name, suffix) == 0) { 373 mult = suffixes[i].mult; 374 break; 375 } 376 } 377 378 if (suffixes[i].name == NULL && *suffix != '\0') 379 return; 380 381 if (mult == 0) { 382 /* 383 * The default is frequency-per-second. 384 */ 385 val = NANOSEC / val; 386 } else { 387 val *= mult; 388 } 389 390 profile_create(val, name, kind); 391 } 392 393 /* ARGSUSED */ 394 static void 395 profile_destroy(void *arg, dtrace_id_t id, void *parg) 396 { 397 profile_probe_t *prof = parg; 398 399 ASSERT(prof->prof_cyclic == CYCLIC_NONE); 400 kmem_free(prof, sizeof (profile_probe_t)); 401 402 ASSERT(profile_total >= 1); 403 atomic_add_32(&profile_total, -1); 404 } 405 406 /*ARGSUSED*/ 407 static void 408 profile_online(void *arg, cpu_t *cpu, cyc_handler_t *hdlr, cyc_time_t *when) 409 { 410 profile_probe_t *prof = arg; 411 profile_probe_percpu_t *pcpu; 412 413 pcpu = kmem_zalloc(sizeof (profile_probe_percpu_t), KM_SLEEP); 414 pcpu->profc_probe = prof; 415 416 hdlr->cyh_func = profile_fire; 417 hdlr->cyh_arg = pcpu; 418 419 when->cyt_interval = prof->prof_interval; 420 when->cyt_when = gethrtime() + when->cyt_interval; 421 422 pcpu->profc_expected = when->cyt_when; 423 pcpu->profc_interval = when->cyt_interval; 424 } 425 426 /*ARGSUSED*/ 427 static void 428 profile_offline(void *arg, cpu_t *cpu, void *oarg) 429 { 430 profile_probe_percpu_t *pcpu = oarg; 431 432 ASSERT(pcpu->profc_probe == arg); 433 kmem_free(pcpu, sizeof (profile_probe_percpu_t)); 434 } 435 436 /* ARGSUSED */ 437 static void 438 profile_enable(void *arg, dtrace_id_t id, void *parg) 439 { 440 profile_probe_t *prof = parg; 441 cyc_omni_handler_t omni; 442 cyc_handler_t hdlr; 443 cyc_time_t when; 444 445 ASSERT(prof->prof_interval != 0); 446 ASSERT(MUTEX_HELD(&cpu_lock)); 447 448 if (prof->prof_kind == PROF_TICK) { 449 hdlr.cyh_func = profile_tick; 450 hdlr.cyh_arg = prof; 451 452 when.cyt_interval = prof->prof_interval; 453 when.cyt_when = gethrtime() + when.cyt_interval; 454 } else { 455 ASSERT(prof->prof_kind == PROF_PROFILE); 456 omni.cyo_online = profile_online; 457 omni.cyo_offline = profile_offline; 458 omni.cyo_arg = prof; 459 } 460 461 if (prof->prof_kind == PROF_TICK) { 462 prof->prof_cyclic = cyclic_add(&hdlr, &when); 463 } else { 464 prof->prof_cyclic = cyclic_add_omni(&omni); 465 } 466 } 467 468 /* ARGSUSED */ 469 static void 470 profile_disable(void *arg, dtrace_id_t id, void *parg) 471 { 472 profile_probe_t *prof = parg; 473 474 ASSERT(prof->prof_cyclic != CYCLIC_NONE); 475 ASSERT(MUTEX_HELD(&cpu_lock)); 476 477 cyclic_remove(prof->prof_cyclic); 478 prof->prof_cyclic = CYCLIC_NONE; 479 } 480 481 static void 482 profile_load(void *dummy) 483 { 484 /* Create the /dev/dtrace/profile entry. */ 485 profile_cdev = make_dev(&profile_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, 486 "dtrace/profile"); 487 488 if (dtrace_register("profile", &profile_attr, DTRACE_PRIV_USER, 489 NULL, &profile_pops, NULL, &profile_id) != 0) 490 return; 491 } 492 493 494 static int 495 profile_unload() 496 { 497 int error = 0; 498 499 if ((error = dtrace_unregister(profile_id)) != 0) 500 return (error); 501 502 destroy_dev(profile_cdev); 503 504 return (error); 505 } 506 507 /* ARGSUSED */ 508 static int 509 profile_modevent(module_t mod __unused, int type, void *data __unused) 510 { 511 int error = 0; 512 513 switch (type) { 514 case MOD_LOAD: 515 break; 516 517 case MOD_UNLOAD: 518 break; 519 520 case MOD_SHUTDOWN: 521 break; 522 523 default: 524 error = EOPNOTSUPP; 525 break; 526 527 } 528 return (error); 529 } 530 531 /* ARGSUSED */ 532 static int 533 profile_open(struct cdev *dev __unused, int oflags __unused, int devtype __unused, struct thread *td __unused) 534 { 535 return (0); 536 } 537 538 SYSINIT(profile_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, profile_load, NULL); 539 SYSUNINIT(profile_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, profile_unload, NULL); 540 541 DEV_MODULE(profile, profile_modevent, NULL); 542 MODULE_VERSION(profile, 1); 543 MODULE_DEPEND(profile, dtrace, 1, 1, 1); 544 MODULE_DEPEND(profile, cyclic, 1, 1, 1); 545 MODULE_DEPEND(profile, opensolaris, 1, 1, 1); 546