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 typedef struct profile_probe { 116 char prof_name[PROF_NAMELEN]; 117 dtrace_id_t prof_id; 118 int prof_kind; 119 hrtime_t prof_interval; 120 cyclic_id_t prof_cyclic; 121 } profile_probe_t; 122 123 typedef struct profile_probe_percpu { 124 hrtime_t profc_expected; 125 hrtime_t profc_interval; 126 profile_probe_t *profc_probe; 127 } profile_probe_percpu_t; 128 129 static d_open_t profile_open; 130 static int profile_unload(void); 131 static void profile_create(hrtime_t, char *, int); 132 static void profile_destroy(void *, dtrace_id_t, void *); 133 static void profile_enable(void *, dtrace_id_t, void *); 134 static void profile_disable(void *, dtrace_id_t, void *); 135 static void profile_load(void *); 136 static void profile_provide(void *, dtrace_probedesc_t *); 137 138 static int profile_rates[] = { 139 97, 199, 499, 997, 1999, 140 4001, 4999, 0, 0, 0, 141 0, 0, 0, 0, 0, 142 0, 0, 0, 0, 0 143 }; 144 145 static int profile_ticks[] = { 146 1, 10, 100, 500, 1000, 147 5000, 0, 0, 0, 0, 148 0, 0, 0, 0, 0 149 }; 150 151 /* 152 * profile_max defines the upper bound on the number of profile probes that 153 * can exist (this is to prevent malicious or clumsy users from exhausing 154 * system resources by creating a slew of profile probes). At mod load time, 155 * this gets its value from PROFILE_MAX_DEFAULT or profile-max-probes if it's 156 * present in the profile.conf file. 157 */ 158 #define PROFILE_MAX_DEFAULT 1000 /* default max. number of probes */ 159 static uint32_t profile_max = PROFILE_MAX_DEFAULT; 160 /* maximum number of profile probes */ 161 static uint32_t profile_total; /* current number of profile probes */ 162 163 static struct cdevsw profile_cdevsw = { 164 .d_version = D_VERSION, 165 .d_open = profile_open, 166 .d_name = "profile", 167 }; 168 169 static dtrace_pattr_t profile_attr = { 170 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 171 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, 172 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 173 { DTRACE_STABILITY_EVOLVING, DTRACE_STABILITY_EVOLVING, DTRACE_CLASS_COMMON }, 174 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_ISA }, 175 }; 176 177 static dtrace_pops_t profile_pops = { 178 profile_provide, 179 NULL, 180 profile_enable, 181 profile_disable, 182 NULL, 183 NULL, 184 NULL, 185 NULL, 186 NULL, 187 profile_destroy 188 }; 189 190 static struct cdev *profile_cdev; 191 static dtrace_provider_id_t profile_id; 192 static hrtime_t profile_interval_min = NANOSEC / 5000; /* 5000 hz */ 193 static int profile_aframes = 0; /* override */ 194 195 static void 196 profile_fire(void *arg) 197 { 198 profile_probe_percpu_t *pcpu = arg; 199 profile_probe_t *prof = pcpu->profc_probe; 200 hrtime_t late; 201 solaris_cpu_t *c = &solaris_cpu[curcpu]; 202 203 late = gethrtime() - pcpu->profc_expected; 204 pcpu->profc_expected += pcpu->profc_interval; 205 206 dtrace_probe(prof->prof_id, c->cpu_profile_pc, 207 c->cpu_profile_upc, late, 0, 0); 208 } 209 210 static void 211 profile_tick(void *arg) 212 { 213 profile_probe_t *prof = arg; 214 solaris_cpu_t *c = &solaris_cpu[curcpu]; 215 216 dtrace_probe(prof->prof_id, c->cpu_profile_pc, 217 c->cpu_profile_upc, 0, 0, 0); 218 } 219 220 static void 221 profile_create(hrtime_t interval, char *name, int kind) 222 { 223 profile_probe_t *prof; 224 225 if (interval < profile_interval_min) 226 return; 227 228 if (dtrace_probe_lookup(profile_id, NULL, NULL, name) != 0) 229 return; 230 231 atomic_add_32(&profile_total, 1); 232 if (profile_total > profile_max) { 233 atomic_add_32(&profile_total, -1); 234 return; 235 } 236 237 prof = kmem_zalloc(sizeof (profile_probe_t), KM_SLEEP); 238 (void) strcpy(prof->prof_name, name); 239 prof->prof_interval = interval; 240 prof->prof_cyclic = CYCLIC_NONE; 241 prof->prof_kind = kind; 242 prof->prof_id = dtrace_probe_create(profile_id, 243 NULL, NULL, name, 244 profile_aframes ? profile_aframes : PROF_ARTIFICIAL_FRAMES, prof); 245 } 246 247 /*ARGSUSED*/ 248 static void 249 profile_provide(void *arg, dtrace_probedesc_t *desc) 250 { 251 int i, j, rate, kind; 252 hrtime_t val = 0, mult = 1, len = 0; 253 char *name, *suffix = NULL; 254 255 const struct { 256 char *prefix; 257 int kind; 258 } types[] = { 259 { PROF_PREFIX_PROFILE, PROF_PROFILE }, 260 { PROF_PREFIX_TICK, PROF_TICK }, 261 { 0, 0 } 262 }; 263 264 const struct { 265 char *name; 266 hrtime_t mult; 267 } suffixes[] = { 268 { "ns", NANOSEC / NANOSEC }, 269 { "nsec", NANOSEC / NANOSEC }, 270 { "us", NANOSEC / MICROSEC }, 271 { "usec", NANOSEC / MICROSEC }, 272 { "ms", NANOSEC / MILLISEC }, 273 { "msec", NANOSEC / MILLISEC }, 274 { "s", NANOSEC / SEC }, 275 { "sec", NANOSEC / SEC }, 276 { "m", NANOSEC * (hrtime_t)60 }, 277 { "min", NANOSEC * (hrtime_t)60 }, 278 { "h", NANOSEC * (hrtime_t)(60 * 60) }, 279 { "hour", NANOSEC * (hrtime_t)(60 * 60) }, 280 { "d", NANOSEC * (hrtime_t)(24 * 60 * 60) }, 281 { "day", NANOSEC * (hrtime_t)(24 * 60 * 60) }, 282 { "hz", 0 }, 283 { NULL } 284 }; 285 286 if (desc == NULL) { 287 char n[PROF_NAMELEN]; 288 289 /* 290 * If no description was provided, provide all of our probes. 291 */ 292 for (i = 0; i < sizeof (profile_rates) / sizeof (int); i++) { 293 if ((rate = profile_rates[i]) == 0) 294 continue; 295 296 (void) snprintf(n, PROF_NAMELEN, "%s%d", 297 PROF_PREFIX_PROFILE, rate); 298 profile_create(NANOSEC / rate, n, PROF_PROFILE); 299 } 300 301 for (i = 0; i < sizeof (profile_ticks) / sizeof (int); i++) { 302 if ((rate = profile_ticks[i]) == 0) 303 continue; 304 305 (void) snprintf(n, PROF_NAMELEN, "%s%d", 306 PROF_PREFIX_TICK, rate); 307 profile_create(NANOSEC / rate, n, PROF_TICK); 308 } 309 310 return; 311 } 312 313 name = desc->dtpd_name; 314 315 for (i = 0; types[i].prefix != NULL; i++) { 316 len = strlen(types[i].prefix); 317 318 if (strncmp(name, types[i].prefix, len) != 0) 319 continue; 320 break; 321 } 322 323 if (types[i].prefix == NULL) 324 return; 325 326 kind = types[i].kind; 327 j = strlen(name) - len; 328 329 /* 330 * We need to start before any time suffix. 331 */ 332 for (j = strlen(name); j >= len; j--) { 333 if (name[j] >= '0' && name[j] <= '9') 334 break; 335 suffix = &name[j]; 336 } 337 338 ASSERT(suffix != NULL); 339 340 /* 341 * Now determine the numerical value present in the probe name. 342 */ 343 for (; j >= len; j--) { 344 if (name[j] < '0' || name[j] > '9') 345 return; 346 347 val += (name[j] - '0') * mult; 348 mult *= (hrtime_t)10; 349 } 350 351 if (val == 0) 352 return; 353 354 /* 355 * Look-up the suffix to determine the multiplier. 356 */ 357 for (i = 0, mult = 0; suffixes[i].name != NULL; i++) { 358 if (strcasecmp(suffixes[i].name, suffix) == 0) { 359 mult = suffixes[i].mult; 360 break; 361 } 362 } 363 364 if (suffixes[i].name == NULL && *suffix != '\0') 365 return; 366 367 if (mult == 0) { 368 /* 369 * The default is frequency-per-second. 370 */ 371 val = NANOSEC / val; 372 } else { 373 val *= mult; 374 } 375 376 profile_create(val, name, kind); 377 } 378 379 /* ARGSUSED */ 380 static void 381 profile_destroy(void *arg, dtrace_id_t id, void *parg) 382 { 383 profile_probe_t *prof = parg; 384 385 ASSERT(prof->prof_cyclic == CYCLIC_NONE); 386 kmem_free(prof, sizeof (profile_probe_t)); 387 388 ASSERT(profile_total >= 1); 389 atomic_add_32(&profile_total, -1); 390 } 391 392 /*ARGSUSED*/ 393 static void 394 profile_online(void *arg, cpu_t *cpu, cyc_handler_t *hdlr, cyc_time_t *when) 395 { 396 profile_probe_t *prof = arg; 397 profile_probe_percpu_t *pcpu; 398 399 pcpu = kmem_zalloc(sizeof (profile_probe_percpu_t), KM_SLEEP); 400 pcpu->profc_probe = prof; 401 402 hdlr->cyh_func = profile_fire; 403 hdlr->cyh_arg = pcpu; 404 405 when->cyt_interval = prof->prof_interval; 406 when->cyt_when = gethrtime() + when->cyt_interval; 407 408 pcpu->profc_expected = when->cyt_when; 409 pcpu->profc_interval = when->cyt_interval; 410 } 411 412 /*ARGSUSED*/ 413 static void 414 profile_offline(void *arg, cpu_t *cpu, void *oarg) 415 { 416 profile_probe_percpu_t *pcpu = oarg; 417 418 ASSERT(pcpu->profc_probe == arg); 419 kmem_free(pcpu, sizeof (profile_probe_percpu_t)); 420 } 421 422 /* ARGSUSED */ 423 static void 424 profile_enable(void *arg, dtrace_id_t id, void *parg) 425 { 426 profile_probe_t *prof = parg; 427 cyc_omni_handler_t omni; 428 cyc_handler_t hdlr; 429 cyc_time_t when; 430 431 ASSERT(prof->prof_interval != 0); 432 ASSERT(MUTEX_HELD(&cpu_lock)); 433 434 if (prof->prof_kind == PROF_TICK) { 435 hdlr.cyh_func = profile_tick; 436 hdlr.cyh_arg = prof; 437 438 when.cyt_interval = prof->prof_interval; 439 when.cyt_when = gethrtime() + when.cyt_interval; 440 } else { 441 ASSERT(prof->prof_kind == PROF_PROFILE); 442 omni.cyo_online = profile_online; 443 omni.cyo_offline = profile_offline; 444 omni.cyo_arg = prof; 445 } 446 447 if (prof->prof_kind == PROF_TICK) { 448 prof->prof_cyclic = cyclic_add(&hdlr, &when); 449 } else { 450 prof->prof_cyclic = cyclic_add_omni(&omni); 451 } 452 } 453 454 /* ARGSUSED */ 455 static void 456 profile_disable(void *arg, dtrace_id_t id, void *parg) 457 { 458 profile_probe_t *prof = parg; 459 460 ASSERT(prof->prof_cyclic != CYCLIC_NONE); 461 ASSERT(MUTEX_HELD(&cpu_lock)); 462 463 cyclic_remove(prof->prof_cyclic); 464 prof->prof_cyclic = CYCLIC_NONE; 465 } 466 467 static void 468 profile_load(void *dummy) 469 { 470 /* Create the /dev/dtrace/profile entry. */ 471 profile_cdev = make_dev(&profile_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, 472 "dtrace/profile"); 473 474 if (dtrace_register("profile", &profile_attr, DTRACE_PRIV_USER, 475 NULL, &profile_pops, NULL, &profile_id) != 0) 476 return; 477 } 478 479 480 static int 481 profile_unload() 482 { 483 int error = 0; 484 485 if ((error = dtrace_unregister(profile_id)) != 0) 486 return (error); 487 488 destroy_dev(profile_cdev); 489 490 return (error); 491 } 492 493 /* ARGSUSED */ 494 static int 495 profile_modevent(module_t mod __unused, int type, void *data __unused) 496 { 497 int error = 0; 498 499 switch (type) { 500 case MOD_LOAD: 501 break; 502 503 case MOD_UNLOAD: 504 break; 505 506 case MOD_SHUTDOWN: 507 break; 508 509 default: 510 error = EOPNOTSUPP; 511 break; 512 513 } 514 return (error); 515 } 516 517 /* ARGSUSED */ 518 static int 519 profile_open(struct cdev *dev __unused, int oflags __unused, int devtype __unused, struct thread *td __unused) 520 { 521 return (0); 522 } 523 524 SYSINIT(profile_load, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, profile_load, NULL); 525 SYSUNINIT(profile_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, profile_unload, NULL); 526 527 DEV_MODULE(profile, profile_modevent, NULL); 528 MODULE_VERSION(profile, 1); 529 MODULE_DEPEND(profile, dtrace, 1, 1, 1); 530 MODULE_DEPEND(profile, cyclic, 1, 1, 1); 531 MODULE_DEPEND(profile, opensolaris, 1, 1, 1); 532