1 /* 2 * Copyright (c) 2005 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 /* 35 * The following copyright applies to the DDB command code: 36 * 37 * Copyright (c) 2000 John Baldwin <jhb@FreeBSD.org> 38 * All rights reserved. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. Neither the name of the author nor the names of any co-contributors 49 * may be used to endorse or promote products derived from this software 50 * without specific prior written permission. 51 * 52 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 55 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 62 * SUCH DAMAGE. 63 */ 64 65 /* 66 * Kernel tracepoint facility. 67 */ 68 69 #include "opt_ddb.h" 70 #include "opt_ktr.h" 71 72 #include <sys/param.h> 73 #include <sys/cons.h> 74 #include <sys/kernel.h> 75 #include <sys/libkern.h> 76 #include <sys/proc.h> 77 #include <sys/sysctl.h> 78 #include <sys/ktr.h> 79 #include <sys/systm.h> 80 #include <sys/time.h> 81 #include <sys/malloc.h> 82 #include <sys/spinlock.h> 83 #include <sys/thread2.h> 84 #include <sys/spinlock2.h> 85 #include <sys/ctype.h> 86 87 #include <machine/cpu.h> 88 #include <machine/cpufunc.h> 89 #include <machine/specialreg.h> 90 #include <machine/md_var.h> 91 92 #include <ddb/ddb.h> 93 94 #ifndef KTR_ENTRIES 95 #define KTR_ENTRIES 2048 96 #elif (KTR_ENTRIES & KTR_ENTRIES - 1) 97 #error KTR_ENTRIES must be a power of two 98 #endif 99 #define KTR_ENTRIES_MASK (KTR_ENTRIES - 1) 100 101 /* 102 * test logging support. When ktr_testlogcnt is non-zero each synchronization 103 * interrupt will issue six back-to-back ktr logging messages on cpu 0 104 * so the user can determine KTR logging overheads. 105 */ 106 #if !defined(KTR_TESTLOG) 107 #define KTR_TESTLOG KTR_ALL 108 #endif 109 KTR_INFO_MASTER(testlog); 110 #if KTR_TESTLOG 111 KTR_INFO(KTR_TESTLOG, testlog, test1, 0, "test1 %d %d %d %d", int dummy1, int dummy2, int dummy3, int dummy4); 112 KTR_INFO(KTR_TESTLOG, testlog, test2, 1, "test2 %d %d %d %d", int dummy1, int dummy2, int dummy3, int dummy4); 113 KTR_INFO(KTR_TESTLOG, testlog, test3, 2, "test3 %d %d %d %d", int dummy1, int dummy2, int dummy3, int dummy4); 114 KTR_INFO(KTR_TESTLOG, testlog, test4, 3, "test4"); 115 KTR_INFO(KTR_TESTLOG, testlog, test5, 4, "test5"); 116 KTR_INFO(KTR_TESTLOG, testlog, test6, 5, "test6"); 117 KTR_INFO(KTR_TESTLOG, testlog, pingpong, 6, "pingpong"); 118 KTR_INFO(KTR_TESTLOG, testlog, pipeline, 7, "pipeline"); 119 KTR_INFO(KTR_TESTLOG, testlog, crit_beg, 8, "crit_beg"); 120 KTR_INFO(KTR_TESTLOG, testlog, crit_end, 9, "crit_end"); 121 KTR_INFO(KTR_TESTLOG, testlog, spin_beg, 10, "spin_beg"); 122 KTR_INFO(KTR_TESTLOG, testlog, spin_end, 11, "spin_end"); 123 #define logtest(name) KTR_LOG(testlog_ ## name, 0, 0, 0, 0) 124 #define logtest_noargs(name) KTR_LOG(testlog_ ## name) 125 #endif 126 127 MALLOC_DEFINE(M_KTR, "ktr", "ktr buffers"); 128 129 SYSCTL_NODE(_debug, OID_AUTO, ktr, CTLFLAG_RW, 0, "ktr"); 130 131 int ktr_entries = KTR_ENTRIES; 132 SYSCTL_INT(_debug_ktr, OID_AUTO, entries, CTLFLAG_RD, &ktr_entries, 0, 133 "Size of the event buffer"); 134 135 int ktr_version = KTR_VERSION; 136 SYSCTL_INT(_debug_ktr, OID_AUTO, version, CTLFLAG_RD, &ktr_version, 0, ""); 137 138 static int ktr_stacktrace = 1; 139 SYSCTL_INT(_debug_ktr, OID_AUTO, stacktrace, CTLFLAG_RD, &ktr_stacktrace, 0, ""); 140 141 static int ktr_resynchronize = 0; 142 SYSCTL_INT(_debug_ktr, OID_AUTO, resynchronize, CTLFLAG_RW, 143 &ktr_resynchronize, 0, "Resynchronize TSC 10 times a second"); 144 145 #if KTR_TESTLOG 146 static int ktr_testlogcnt = 0; 147 SYSCTL_INT(_debug_ktr, OID_AUTO, testlogcnt, CTLFLAG_RW, &ktr_testlogcnt, 0, ""); 148 static int ktr_testipicnt = 0; 149 static int ktr_testipicnt_remainder; 150 SYSCTL_INT(_debug_ktr, OID_AUTO, testipicnt, CTLFLAG_RW, &ktr_testipicnt, 0, ""); 151 static int ktr_testcritcnt = 0; 152 SYSCTL_INT(_debug_ktr, OID_AUTO, testcritcnt, CTLFLAG_RW, &ktr_testcritcnt, 0, ""); 153 static int ktr_testspincnt = 0; 154 SYSCTL_INT(_debug_ktr, OID_AUTO, testspincnt, CTLFLAG_RW, &ktr_testspincnt, 0, ""); 155 #endif 156 157 /* 158 * Give cpu0 a static buffer so the tracepoint facility can be used during 159 * early boot (note however that we still use a critical section, XXX). 160 */ 161 static struct ktr_entry ktr_buf0[KTR_ENTRIES]; 162 163 struct ktr_cpu ktr_cpu[MAXCPU] = { 164 { .core.ktr_buf = &ktr_buf0[0] } 165 }; 166 167 static int64_t ktr_sync_tsc; 168 struct callout ktr_resync_callout; 169 170 #ifdef KTR_VERBOSE 171 int ktr_verbose = KTR_VERBOSE; 172 TUNABLE_INT("debug.ktr.verbose", &ktr_verbose); 173 SYSCTL_INT(_debug_ktr, OID_AUTO, verbose, CTLFLAG_RW, &ktr_verbose, 0, 174 "Log events to the console as well"); 175 #endif 176 177 static void ktr_resync_callback(void *dummy __unused); 178 179 extern int64_t tsc_offsets[]; 180 181 static void 182 ktr_sysinit(void *dummy) 183 { 184 struct ktr_cpu_core *kcpu; 185 int i; 186 187 for(i = 1; i < ncpus; ++i) { 188 kcpu = &ktr_cpu[i].core; 189 kcpu->ktr_buf = kmalloc(KTR_ENTRIES * sizeof(struct ktr_entry), 190 M_KTR, M_WAITOK | M_ZERO); 191 } 192 callout_init_mp(&ktr_resync_callout); 193 callout_reset(&ktr_resync_callout, hz / 10, ktr_resync_callback, NULL); 194 } 195 SYSINIT(ktr_sysinit, SI_BOOT2_KLD, SI_ORDER_ANY, ktr_sysinit, NULL); 196 197 /* 198 * Try to resynchronize the TSC's for all cpus. This is really, really nasty. 199 * We have to send an IPIQ message to all remote cpus, wait until they 200 * get into their IPIQ processing code loop, then do an even stricter hard 201 * loop to get the cpus as close to synchronized as we can to get the most 202 * accurate reading. 203 * 204 * This callback occurs on cpu0. 205 */ 206 #if KTR_TESTLOG 207 static void ktr_pingpong_remote(void *dummy); 208 static void ktr_pipeline_remote(void *dummy); 209 #endif 210 211 #ifdef _RDTSC_SUPPORTED_ 212 213 static void ktr_resync_remote(void *dummy); 214 215 /* 216 * We use a callout callback instead of a systimer because we cannot afford 217 * to preempt anyone to do this, or we might deadlock a spin-lock or 218 * serializer between two cpus. 219 */ 220 static 221 void 222 ktr_resync_callback(void *dummy __unused) 223 { 224 struct lwkt_cpusync cs; 225 #if KTR_TESTLOG 226 int count; 227 #endif 228 229 KKASSERT(mycpu->gd_cpuid == 0); 230 231 #if KTR_TESTLOG 232 /* 233 * Test logging 234 */ 235 if (ktr_testlogcnt) { 236 --ktr_testlogcnt; 237 cpu_disable_intr(); 238 logtest(test1); 239 logtest(test2); 240 logtest(test3); 241 logtest_noargs(test4); 242 logtest_noargs(test5); 243 logtest_noargs(test6); 244 cpu_enable_intr(); 245 } 246 247 /* 248 * Test IPI messaging 249 */ 250 if (ktr_testipicnt && ktr_testipicnt_remainder == 0 && ncpus > 1) { 251 ktr_testipicnt_remainder = ktr_testipicnt; 252 ktr_testipicnt = 0; 253 lwkt_send_ipiq_bycpu(1, ktr_pingpong_remote, NULL); 254 } 255 256 /* 257 * Test critical sections 258 */ 259 if (ktr_testcritcnt) { 260 crit_enter(); 261 crit_exit(); 262 logtest_noargs(crit_beg); 263 for (count = ktr_testcritcnt; count; --count) { 264 crit_enter(); 265 crit_exit(); 266 } 267 logtest_noargs(crit_end); 268 ktr_testcritcnt = 0; 269 } 270 271 /* 272 * Test spinlock sections 273 */ 274 if (ktr_testspincnt) { 275 struct spinlock spin; 276 277 spin_init(&spin); 278 spin_lock(&spin); 279 spin_unlock(&spin); 280 logtest_noargs(spin_beg); 281 for (count = ktr_testspincnt; count; --count) { 282 spin_lock(&spin); 283 spin_unlock(&spin); 284 } 285 logtest_noargs(spin_end); 286 ktr_testspincnt = 0; 287 } 288 #endif 289 290 /* 291 * Resynchronize the TSC 292 */ 293 if (ktr_resynchronize == 0) 294 goto done; 295 if ((cpu_feature & CPUID_TSC) == 0) 296 return; 297 298 crit_enter(); 299 lwkt_cpusync_init(&cs, smp_active_mask, ktr_resync_remote, 300 (void *)(intptr_t)mycpu->gd_cpuid); 301 lwkt_cpusync_interlock(&cs); 302 ktr_sync_tsc = rdtsc(); 303 lwkt_cpusync_deinterlock(&cs); 304 crit_exit(); 305 done: 306 callout_reset(&ktr_resync_callout, hz / 10, ktr_resync_callback, NULL); 307 } 308 309 /* 310 * The remote-end of the KTR synchronization protocol runs on all cpus. 311 * The one we run on the controlling cpu updates its tsc continuously 312 * until the others have finished syncing (theoretically), but we don't 313 * loop forever. 314 * 315 * This is a bit ad-hoc but we need to avoid livelocking inside an IPI 316 * callback. rdtsc() is a synchronizing instruction (I think). 317 */ 318 static void 319 ktr_resync_remote(void *arg) 320 { 321 globaldata_t gd = mycpu; 322 int64_t delta; 323 int i; 324 325 if (gd->gd_cpuid == (int)(intptr_t)arg) { 326 for (i = 0; i < 2000; ++i) 327 ktr_sync_tsc = rdtsc(); 328 } else { 329 delta = rdtsc() - ktr_sync_tsc; 330 if (tsc_offsets[gd->gd_cpuid] == 0) 331 tsc_offsets[gd->gd_cpuid] = delta; 332 tsc_offsets[gd->gd_cpuid] = 333 (tsc_offsets[gd->gd_cpuid] * 7 + delta) / 8; 334 } 335 } 336 337 #if KTR_TESTLOG 338 339 static 340 void 341 ktr_pingpong_remote(void *dummy __unused) 342 { 343 int other_cpu; 344 345 logtest_noargs(pingpong); 346 other_cpu = 1 - mycpu->gd_cpuid; 347 if (ktr_testipicnt_remainder) { 348 --ktr_testipicnt_remainder; 349 lwkt_send_ipiq_bycpu(other_cpu, ktr_pingpong_remote, NULL); 350 } else { 351 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL); 352 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL); 353 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL); 354 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL); 355 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL); 356 } 357 } 358 359 static 360 void 361 ktr_pipeline_remote(void *dummy __unused) 362 { 363 logtest_noargs(pipeline); 364 } 365 366 #endif 367 368 #else /* !_RDTSC_SUPPORTED_ */ 369 370 /* 371 * The resync callback for UP doesn't do anything other then run the test 372 * log messages. If test logging is not enabled, don't bother resetting 373 * the callout. 374 */ 375 static 376 void 377 ktr_resync_callback(void *dummy __unused) 378 { 379 #if KTR_TESTLOG 380 /* 381 * Test logging 382 */ 383 if (ktr_testlogcnt) { 384 --ktr_testlogcnt; 385 cpu_disable_intr(); 386 logtest(test1); 387 logtest(test2); 388 logtest(test3); 389 logtest_noargs(test4); 390 logtest_noargs(test5); 391 logtest_noargs(test6); 392 cpu_enable_intr(); 393 } 394 callout_reset(&ktr_resync_callout, hz / 10, ktr_resync_callback, NULL); 395 #endif 396 } 397 398 #endif 399 400 /* 401 * Setup the next empty slot and return it to the caller to store the data 402 * directly. 403 */ 404 struct ktr_entry * 405 ktr_begin_write_entry(struct ktr_info *info, const char *file, int line) 406 { 407 struct ktr_cpu_core *kcpu; 408 struct ktr_entry *entry; 409 int cpu; 410 411 cpu = mycpu->gd_cpuid; 412 kcpu = &ktr_cpu[cpu].core; 413 if (panicstr) /* stop logging during panic */ 414 return NULL; 415 if (kcpu->ktr_buf == NULL) /* too early in boot */ 416 return NULL; 417 418 crit_enter(); 419 entry = kcpu->ktr_buf + (kcpu->ktr_idx & KTR_ENTRIES_MASK); 420 ++kcpu->ktr_idx; 421 #ifdef _RDTSC_SUPPORTED_ 422 if (cpu_feature & CPUID_TSC) { 423 entry->ktr_timestamp = rdtsc() - tsc_offsets[cpu]; 424 } else 425 #endif 426 { 427 entry->ktr_timestamp = get_approximate_time_t(); 428 } 429 entry->ktr_info = info; 430 entry->ktr_file = file; 431 entry->ktr_line = line; 432 crit_exit(); 433 return entry; 434 } 435 436 int 437 ktr_finish_write_entry(struct ktr_info *info, struct ktr_entry *entry) 438 { 439 if (ktr_stacktrace) 440 cpu_ktr_caller(entry); 441 #ifdef KTR_VERBOSE 442 if (ktr_verbose && info->kf_format) { 443 kprintf("cpu%d ", mycpu->gd_cpuid); 444 if (ktr_verbose > 1) { 445 kprintf("%s.%d\t", entry->ktr_file, entry->ktr_line); 446 } 447 return !0; 448 } 449 #endif 450 return 0; 451 } 452 453 #ifdef DDB 454 455 #define NUM_LINES_PER_PAGE 19 456 457 struct tstate { 458 int cur; 459 int first; 460 }; 461 462 static int db_ktr_verbose; 463 static int db_mach_vtrace(int cpu, struct ktr_entry *kp, int idx); 464 465 DB_SHOW_COMMAND(ktr, db_ktr_all) 466 { 467 struct ktr_cpu_core *kcpu; 468 int a_flag = 0; 469 int c; 470 int nl = 0; 471 int i; 472 struct tstate tstate[MAXCPU]; 473 int printcpu = -1; 474 475 for(i = 0; i < ncpus; i++) { 476 kcpu = &ktr_cpu[i].core; 477 tstate[i].first = -1; 478 tstate[i].cur = (kcpu->ktr_idx - 1) & KTR_ENTRIES_MASK; 479 } 480 db_ktr_verbose = 0; 481 while ((c = *(modif++)) != '\0') { 482 if (c == 'v') { 483 db_ktr_verbose = 1; 484 } 485 else if (c == 'a') { 486 a_flag = 1; 487 } 488 else if (c == 'c') { 489 printcpu = 0; 490 while ((c = *(modif++)) != '\0') { 491 if (isdigit(c)) { 492 printcpu *= 10; 493 printcpu += c - '0'; 494 } 495 else { 496 modif++; 497 break; 498 } 499 } 500 modif--; 501 } 502 } 503 if (printcpu > ncpus - 1) { 504 db_printf("Invalid cpu number\n"); 505 return; 506 } 507 /* 508 * Lopp throug all the buffers and print the content of them, sorted 509 * by the timestamp. 510 */ 511 while (1) { 512 int counter; 513 u_int64_t highest_ts; 514 int highest_cpu; 515 struct ktr_entry *kp; 516 517 if (a_flag == 1 && cncheckc() != -1) 518 return; 519 highest_ts = 0; 520 highest_cpu = -1; 521 /* 522 * Find the lowest timestamp 523 */ 524 for (i = 0, counter = 0; i < ncpus; i++) { 525 kcpu = &ktr_cpu[i].core; 526 if (kcpu->ktr_buf == NULL) 527 continue; 528 if (printcpu != -1 && printcpu != i) 529 continue; 530 if (tstate[i].cur == -1) { 531 counter++; 532 if (counter == ncpus) { 533 db_printf("--- End of trace buffer ---\n"); 534 return; 535 } 536 continue; 537 } 538 if (kcpu->ktr_buf[tstate[i].cur].ktr_timestamp > highest_ts) { 539 highest_ts = kcpu->ktr_buf[tstate[i].cur].ktr_timestamp; 540 highest_cpu = i; 541 } 542 } 543 if (highest_cpu < 0) { 544 db_printf("no KTR data available\n"); 545 break; 546 } 547 i = highest_cpu; 548 kcpu = &ktr_cpu[i].core; 549 kp = &kcpu->ktr_buf[tstate[i].cur]; 550 if (tstate[i].first == -1) 551 tstate[i].first = tstate[i].cur; 552 if (--tstate[i].cur < 0) 553 tstate[i].cur = KTR_ENTRIES - 1; 554 if (tstate[i].first == tstate[i].cur) { 555 db_mach_vtrace(i, kp, tstate[i].cur + 1); 556 tstate[i].cur = -1; 557 continue; 558 } 559 if (kcpu->ktr_buf[tstate[i].cur].ktr_info == NULL) 560 tstate[i].cur = -1; 561 if (db_more(&nl) == -1) 562 break; 563 if (db_mach_vtrace(i, kp, tstate[i].cur + 1) == 0) 564 tstate[i].cur = -1; 565 } 566 } 567 568 static int 569 db_mach_vtrace(int cpu, struct ktr_entry *kp, int idx) 570 { 571 if (kp->ktr_info == NULL) 572 return(0); 573 db_printf("cpu%d ", cpu); 574 db_printf("%d: ", idx); 575 if (db_ktr_verbose) { 576 db_printf("%10.10lld %s.%d\t", (long long)kp->ktr_timestamp, 577 kp->ktr_file, kp->ktr_line); 578 } 579 db_printf("%s\t", kp->ktr_info->kf_name); 580 db_printf("from(%p,%p) ", kp->ktr_caller1, kp->ktr_caller2); 581 #ifdef __i386__ 582 if (kp->ktr_info->kf_format) 583 db_vprintf(kp->ktr_info->kf_format, (__va_list)kp->ktr_data); 584 #endif 585 db_printf("\n"); 586 587 return(1); 588 } 589 590 #endif /* DDB */ 591