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 extern cpumask_t smp_active_mask; 215 216 /* 217 * We use a callout callback instead of a systimer because we cannot afford 218 * to preempt anyone to do this, or we might deadlock a spin-lock or 219 * serializer between two cpus. 220 */ 221 static 222 void 223 ktr_resync_callback(void *dummy __unused) 224 { 225 struct lwkt_cpusync cs; 226 #if KTR_TESTLOG 227 int count; 228 #endif 229 230 KKASSERT(mycpu->gd_cpuid == 0); 231 232 #if KTR_TESTLOG 233 /* 234 * Test logging 235 */ 236 if (ktr_testlogcnt) { 237 --ktr_testlogcnt; 238 cpu_disable_intr(); 239 logtest(test1); 240 logtest(test2); 241 logtest(test3); 242 logtest_noargs(test4); 243 logtest_noargs(test5); 244 logtest_noargs(test6); 245 cpu_enable_intr(); 246 } 247 248 /* 249 * Test IPI messaging 250 */ 251 if (ktr_testipicnt && ktr_testipicnt_remainder == 0 && ncpus > 1) { 252 ktr_testipicnt_remainder = ktr_testipicnt; 253 ktr_testipicnt = 0; 254 lwkt_send_ipiq_bycpu(1, ktr_pingpong_remote, NULL); 255 } 256 257 /* 258 * Test critical sections 259 */ 260 if (ktr_testcritcnt) { 261 crit_enter(); 262 crit_exit(); 263 logtest_noargs(crit_beg); 264 for (count = ktr_testcritcnt; count; --count) { 265 crit_enter(); 266 crit_exit(); 267 } 268 logtest_noargs(crit_end); 269 ktr_testcritcnt = 0; 270 } 271 272 /* 273 * Test spinlock sections 274 */ 275 if (ktr_testspincnt) { 276 struct spinlock spin; 277 278 spin_init(&spin); 279 spin_lock(&spin); 280 spin_unlock(&spin); 281 logtest_noargs(spin_beg); 282 for (count = ktr_testspincnt; count; --count) { 283 spin_lock(&spin); 284 spin_unlock(&spin); 285 } 286 logtest_noargs(spin_end); 287 ktr_testspincnt = 0; 288 } 289 #endif 290 291 /* 292 * Resynchronize the TSC 293 */ 294 if (ktr_resynchronize == 0) 295 goto done; 296 if ((cpu_feature & CPUID_TSC) == 0) 297 return; 298 299 crit_enter(); 300 lwkt_cpusync_init(&cs, smp_active_mask, ktr_resync_remote, 301 (void *)(intptr_t)mycpu->gd_cpuid); 302 lwkt_cpusync_interlock(&cs); 303 ktr_sync_tsc = rdtsc(); 304 lwkt_cpusync_deinterlock(&cs); 305 crit_exit(); 306 done: 307 callout_reset(&ktr_resync_callout, hz / 10, ktr_resync_callback, NULL); 308 } 309 310 /* 311 * The remote-end of the KTR synchronization protocol runs on all cpus. 312 * The one we run on the controlling cpu updates its tsc continuously 313 * until the others have finished syncing (theoretically), but we don't 314 * loop forever. 315 * 316 * This is a bit ad-hoc but we need to avoid livelocking inside an IPI 317 * callback. rdtsc() is a synchronizing instruction (I think). 318 */ 319 static void 320 ktr_resync_remote(void *arg) 321 { 322 globaldata_t gd = mycpu; 323 int64_t delta; 324 int i; 325 326 if (gd->gd_cpuid == (int)(intptr_t)arg) { 327 for (i = 0; i < 2000; ++i) 328 ktr_sync_tsc = rdtsc(); 329 } else { 330 delta = rdtsc() - ktr_sync_tsc; 331 if (tsc_offsets[gd->gd_cpuid] == 0) 332 tsc_offsets[gd->gd_cpuid] = delta; 333 tsc_offsets[gd->gd_cpuid] = 334 (tsc_offsets[gd->gd_cpuid] * 7 + delta) / 8; 335 } 336 } 337 338 #if KTR_TESTLOG 339 340 static 341 void 342 ktr_pingpong_remote(void *dummy __unused) 343 { 344 int other_cpu; 345 346 logtest_noargs(pingpong); 347 other_cpu = 1 - mycpu->gd_cpuid; 348 if (ktr_testipicnt_remainder) { 349 --ktr_testipicnt_remainder; 350 lwkt_send_ipiq_bycpu(other_cpu, ktr_pingpong_remote, NULL); 351 } else { 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 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL); 357 } 358 } 359 360 static 361 void 362 ktr_pipeline_remote(void *dummy __unused) 363 { 364 logtest_noargs(pipeline); 365 } 366 367 #endif 368 369 #else /* !_RDTSC_SUPPORTED_ */ 370 371 /* 372 * The resync callback for UP doesn't do anything other then run the test 373 * log messages. If test logging is not enabled, don't bother resetting 374 * the callout. 375 */ 376 static 377 void 378 ktr_resync_callback(void *dummy __unused) 379 { 380 #if KTR_TESTLOG 381 /* 382 * Test logging 383 */ 384 if (ktr_testlogcnt) { 385 --ktr_testlogcnt; 386 cpu_disable_intr(); 387 logtest(test1); 388 logtest(test2); 389 logtest(test3); 390 logtest_noargs(test4); 391 logtest_noargs(test5); 392 logtest_noargs(test6); 393 cpu_enable_intr(); 394 } 395 callout_reset(&ktr_resync_callout, hz / 10, ktr_resync_callback, NULL); 396 #endif 397 } 398 399 #endif 400 401 /* 402 * Setup the next empty slot and return it to the caller to store the data 403 * directly. 404 */ 405 struct ktr_entry * 406 ktr_begin_write_entry(struct ktr_info *info, const char *file, int line) 407 { 408 struct ktr_cpu_core *kcpu; 409 struct ktr_entry *entry; 410 int cpu; 411 412 cpu = mycpu->gd_cpuid; 413 kcpu = &ktr_cpu[cpu].core; 414 if (panicstr) /* stop logging during panic */ 415 return NULL; 416 if (kcpu->ktr_buf == NULL) /* too early in boot */ 417 return NULL; 418 419 crit_enter(); 420 entry = kcpu->ktr_buf + (kcpu->ktr_idx & KTR_ENTRIES_MASK); 421 ++kcpu->ktr_idx; 422 #ifdef _RDTSC_SUPPORTED_ 423 if (cpu_feature & CPUID_TSC) { 424 entry->ktr_timestamp = rdtsc() - tsc_offsets[cpu]; 425 } else 426 #endif 427 { 428 entry->ktr_timestamp = get_approximate_time_t(); 429 } 430 entry->ktr_info = info; 431 entry->ktr_file = file; 432 entry->ktr_line = line; 433 crit_exit(); 434 return entry; 435 } 436 437 int 438 ktr_finish_write_entry(struct ktr_info *info, struct ktr_entry *entry) 439 { 440 if (ktr_stacktrace) 441 cpu_ktr_caller(entry); 442 #ifdef KTR_VERBOSE 443 if (ktr_verbose && info->kf_format) { 444 kprintf("cpu%d ", mycpu->gd_cpuid); 445 if (ktr_verbose > 1) { 446 kprintf("%s.%d\t", entry->ktr_file, entry->ktr_line); 447 } 448 return !0; 449 } 450 #endif 451 return 0; 452 } 453 454 #ifdef DDB 455 456 #define NUM_LINES_PER_PAGE 19 457 458 struct tstate { 459 int cur; 460 int first; 461 }; 462 463 static int db_ktr_verbose; 464 static int db_mach_vtrace(int cpu, struct ktr_entry *kp, int idx); 465 466 DB_SHOW_COMMAND(ktr, db_ktr_all) 467 { 468 struct ktr_cpu_core *kcpu; 469 int a_flag = 0; 470 int c; 471 int nl = 0; 472 int i; 473 struct tstate tstate[MAXCPU]; 474 int printcpu = -1; 475 476 for(i = 0; i < ncpus; i++) { 477 kcpu = &ktr_cpu[i].core; 478 tstate[i].first = -1; 479 tstate[i].cur = (kcpu->ktr_idx - 1) & KTR_ENTRIES_MASK; 480 } 481 db_ktr_verbose = 0; 482 while ((c = *(modif++)) != '\0') { 483 if (c == 'v') { 484 db_ktr_verbose = 1; 485 } 486 else if (c == 'a') { 487 a_flag = 1; 488 } 489 else if (c == 'c') { 490 printcpu = 0; 491 while ((c = *(modif++)) != '\0') { 492 if (isdigit(c)) { 493 printcpu *= 10; 494 printcpu += c - '0'; 495 } 496 else { 497 modif++; 498 break; 499 } 500 } 501 modif--; 502 } 503 } 504 if (printcpu > ncpus - 1) { 505 db_printf("Invalid cpu number\n"); 506 return; 507 } 508 /* 509 * Lopp throug all the buffers and print the content of them, sorted 510 * by the timestamp. 511 */ 512 while (1) { 513 int counter; 514 u_int64_t highest_ts; 515 int highest_cpu; 516 struct ktr_entry *kp; 517 518 if (a_flag == 1 && cncheckc() != -1) 519 return; 520 highest_ts = 0; 521 highest_cpu = -1; 522 /* 523 * Find the lowest timestamp 524 */ 525 for (i = 0, counter = 0; i < ncpus; i++) { 526 kcpu = &ktr_cpu[i].core; 527 if (kcpu->ktr_buf == NULL) 528 continue; 529 if (printcpu != -1 && printcpu != i) 530 continue; 531 if (tstate[i].cur == -1) { 532 counter++; 533 if (counter == ncpus) { 534 db_printf("--- End of trace buffer ---\n"); 535 return; 536 } 537 continue; 538 } 539 if (kcpu->ktr_buf[tstate[i].cur].ktr_timestamp > highest_ts) { 540 highest_ts = kcpu->ktr_buf[tstate[i].cur].ktr_timestamp; 541 highest_cpu = i; 542 } 543 } 544 if (highest_cpu < 0) { 545 db_printf("no KTR data available\n"); 546 break; 547 } 548 i = highest_cpu; 549 kcpu = &ktr_cpu[i].core; 550 kp = &kcpu->ktr_buf[tstate[i].cur]; 551 if (tstate[i].first == -1) 552 tstate[i].first = tstate[i].cur; 553 if (--tstate[i].cur < 0) 554 tstate[i].cur = KTR_ENTRIES - 1; 555 if (tstate[i].first == tstate[i].cur) { 556 db_mach_vtrace(i, kp, tstate[i].cur + 1); 557 tstate[i].cur = -1; 558 continue; 559 } 560 if (kcpu->ktr_buf[tstate[i].cur].ktr_info == NULL) 561 tstate[i].cur = -1; 562 if (db_more(&nl) == -1) 563 break; 564 if (db_mach_vtrace(i, kp, tstate[i].cur + 1) == 0) 565 tstate[i].cur = -1; 566 } 567 } 568 569 static int 570 db_mach_vtrace(int cpu, struct ktr_entry *kp, int idx) 571 { 572 if (kp->ktr_info == NULL) 573 return(0); 574 db_printf("cpu%d ", cpu); 575 db_printf("%d: ", idx); 576 if (db_ktr_verbose) { 577 db_printf("%10.10lld %s.%d\t", (long long)kp->ktr_timestamp, 578 kp->ktr_file, kp->ktr_line); 579 } 580 db_printf("%s\t", kp->ktr_info->kf_name); 581 db_printf("from(%p,%p) ", kp->ktr_caller1, kp->ktr_caller2); 582 #ifdef __i386__ 583 if (kp->ktr_info->kf_format) 584 db_vprintf(kp->ktr_info->kf_format, (__va_list)kp->ktr_data); 585 #endif 586 db_printf("\n"); 587 588 return(1); 589 } 590 591 #endif /* DDB */ 592