sys/kern/kern_ktr.c

   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  * $DragonFly: src/sys/kern/kern_ktr.c,v 1.23 2008/02/12 23:33:23 corecode Exp $
  66  */
  67 /*
  68  * Kernel tracepoint facility.
  69  */
  70
  71 #include "opt_ddb.h"
  72 #include "opt_ktr.h"
  73
  74 #include <sys/param.h>
  75 #include <sys/cons.h>
  76 #include <sys/kernel.h>
  77 #include <sys/libkern.h>
  78 #include <sys/proc.h>
  79 #include <sys/sysctl.h>
  80 #include <sys/ktr.h>
  81 #include <sys/systm.h>
  82 #include <sys/time.h>
  83 #include <sys/malloc.h>
  84 #include <sys/spinlock.h>
  85 #include <sys/thread2.h>
  86 #include <sys/spinlock2.h>
  87 #include <sys/ctype.h>
  88
  89 #include <machine/cpu.h>
  90 #include <machine/cpufunc.h>
  91 #include <machine/specialreg.h>
  92 #include <machine/md_var.h>
  93
  94 #include <ddb/ddb.h>
  95
  96 #ifndef KTR_ENTRIES
  97 #define KTR_ENTRIES             2048
  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", sizeof(void *) * 4);
 112 KTR_INFO(KTR_TESTLOG, testlog, test2, 1, "test2", sizeof(void *) * 4);
 113 KTR_INFO(KTR_TESTLOG, testlog, test3, 2, "test3", sizeof(void *) * 4);
 114 KTR_INFO(KTR_TESTLOG, testlog, test4, 3, "test4", 0);
 115 KTR_INFO(KTR_TESTLOG, testlog, test5, 4, "test5", 0);
 116 KTR_INFO(KTR_TESTLOG, testlog, test6, 5, "test6", 0);
 117 #ifdef SMP
 118 KTR_INFO(KTR_TESTLOG, testlog, pingpong, 6, "pingpong", 0);
 119 KTR_INFO(KTR_TESTLOG, testlog, pipeline, 7, "pipeline", 0);
 120 KTR_INFO(KTR_TESTLOG, testlog, crit_beg, 8, "crit_beg", 0);
 121 KTR_INFO(KTR_TESTLOG, testlog, crit_end, 9, "crit_end", 0);
 122 KTR_INFO(KTR_TESTLOG, testlog, spin_beg, 10, "spin_beg", 0);
 123 KTR_INFO(KTR_TESTLOG, testlog, spin_end, 11, "spin_end", 0);
 124 #endif
 125 #define logtest(name)   KTR_LOG(testlog_ ## name, 0, 0, 0, 0)
 126 #define logtest_noargs(name)    KTR_LOG(testlog_ ## name)
 127 #endif
 128
 129 MALLOC_DEFINE(M_KTR, "ktr", "ktr buffers");
 130
 131 SYSCTL_NODE(_debug, OID_AUTO, ktr, CTLFLAG_RW, 0, "ktr");
 132
 133 int             ktr_entries = KTR_ENTRIES;
 134 SYSCTL_INT(_debug_ktr, OID_AUTO, entries, CTLFLAG_RD, &ktr_entries, 0, "");
 135
 136 int             ktr_version = KTR_VERSION;
 137 SYSCTL_INT(_debug_ktr, OID_AUTO, version, CTLFLAG_RD, &ktr_version, 0, "");
 138
 139 static int      ktr_stacktrace = 1;
 140 SYSCTL_INT(_debug_ktr, OID_AUTO, stacktrace, CTLFLAG_RD, &ktr_stacktrace, 0, "");
 141
 142 static int      ktr_resynchronize = 0;
 143 SYSCTL_INT(_debug_ktr, OID_AUTO, resynchronize, CTLFLAG_RW, &ktr_resynchronize, 0, "");
 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 #ifdef SMP
 150 static int      ktr_testipicnt_remainder;
 151 #endif
 152 SYSCTL_INT(_debug_ktr, OID_AUTO, testipicnt, CTLFLAG_RW, &ktr_testipicnt, 0, "");
 153 static int      ktr_testcritcnt = 0;
 154 SYSCTL_INT(_debug_ktr, OID_AUTO, testcritcnt, CTLFLAG_RW, &ktr_testcritcnt, 0, "");
 155 static int      ktr_testspincnt = 0;
 156 SYSCTL_INT(_debug_ktr, OID_AUTO, testspincnt, CTLFLAG_RW, &ktr_testspincnt, 0, "");
 157 #endif
 158
 159 /*
 160  * Give cpu0 a static buffer so the tracepoint facility can be used during
 161  * early boot (note however that we still use a critical section, XXX).
 162  */
 163 static struct   ktr_entry ktr_buf0[KTR_ENTRIES];
 164
 165 __cachealign struct ktr_cpu ktr_cpu[MAXCPU] = {
 166         { .core.ktr_buf = &ktr_buf0[0] }
 167 };
 168
 169 #ifdef SMP
 170 static int64_t  ktr_sync_tsc;
 171 #endif
 172 struct callout  ktr_resync_callout;
 173
 174 #ifdef KTR_VERBOSE
 175 int     ktr_verbose = KTR_VERBOSE;
 176 TUNABLE_INT("debug.ktr.verbose", &ktr_verbose);
 177 SYSCTL_INT(_debug_ktr, OID_AUTO, verbose, CTLFLAG_RW, &ktr_verbose, 0, "");
 178 #endif
 179
 180 static void ktr_resync_callback(void *dummy __unused);
 181
 182 extern int64_t tsc_offsets[];
 183
 184 static void
 185 ktr_sysinit(void *dummy)
 186 {
 187         struct ktr_cpu_core *kcpu;
 188         int i;
 189
 190         for(i = 1; i < ncpus; ++i) {
 191                 kcpu = &ktr_cpu[i].core;
 192                 kcpu->ktr_buf = kmalloc(KTR_ENTRIES * sizeof(struct ktr_entry),
 193                                         M_KTR, M_WAITOK | M_ZERO);
 194         }
 195         callout_init(&ktr_resync_callout);
 196         callout_reset(&ktr_resync_callout, hz / 10, ktr_resync_callback, NULL);
 197 }
 198 SYSINIT(ktr_sysinit, SI_BOOT2_KLD, SI_ORDER_ANY, ktr_sysinit, NULL);
 199
 200 /*
 201  * Try to resynchronize the TSC's for all cpus.  This is really, really nasty.
 202  * We have to send an IPIQ message to all remote cpus, wait until they
 203  * get into their IPIQ processing code loop, then do an even stricter hard
 204  * loop to get the cpus as close to synchronized as we can to get the most
 205  * accurate reading.
 206  *
 207  * This callback occurs on cpu0.
 208  */
 209 #if KTR_TESTLOG
 210 #ifdef SMP
 211 static void ktr_pingpong_remote(void *dummy);
 212 static void ktr_pipeline_remote(void *dummy);
 213 #endif
 214 #endif
 215
 216 #if defined(SMP) && defined(_RDTSC_SUPPORTED_)
 217
 218 static void ktr_resync_remote(void *dummy);
 219 extern cpumask_t smp_active_mask;
 220
 221 /*
 222  * We use a callout callback instead of a systimer because we cannot afford
 223  * to preempt anyone to do this, or we might deadlock a spin-lock or
 224  * serializer between two cpus.
 225  */
 226 static
 227 void
 228 ktr_resync_callback(void *dummy __unused)
 229 {
 230         struct lwkt_cpusync cs;
 231 #if KTR_TESTLOG
 232         int count;
 233 #endif
 234
 235         KKASSERT(mycpu->gd_cpuid == 0);
 236
 237 #if KTR_TESTLOG
 238         /*
 239          * Test logging
 240          */
 241         if (ktr_testlogcnt) {
 242                 --ktr_testlogcnt;
 243                 cpu_disable_intr();
 244                 logtest(test1);
 245                 logtest(test2);
 246                 logtest(test3);
 247                 logtest_noargs(test4);
 248                 logtest_noargs(test5);
 249                 logtest_noargs(test6);
 250                 cpu_enable_intr();
 251         }
 252
 253         /*
 254          * Test IPI messaging
 255          */
 256         if (ktr_testipicnt && ktr_testipicnt_remainder == 0 && ncpus > 1) {
 257                 ktr_testipicnt_remainder = ktr_testipicnt;
 258                 ktr_testipicnt = 0;
 259                 lwkt_send_ipiq_bycpu(1, ktr_pingpong_remote, NULL);
 260         }
 261
 262         /*
 263          * Test critical sections
 264          */
 265         if (ktr_testcritcnt) {
 266                 crit_enter();
 267                 crit_exit();
 268                 logtest_noargs(crit_beg);
 269                 for (count = ktr_testcritcnt; count; --count) {
 270                         crit_enter();
 271                         crit_exit();
 272                 }
 273                 logtest_noargs(crit_end);
 274                 ktr_testcritcnt = 0;
 275         }
 276
 277         /*
 278          * Test spinlock sections
 279          */
 280         if (ktr_testspincnt) {
 281                 struct spinlock spin;
 282
 283                 spin_init(&spin);
 284                 spin_lock(&spin);
 285                 spin_unlock(&spin);
 286                 logtest_noargs(spin_beg);
 287                 for (count = ktr_testspincnt; count; --count) {
 288                         spin_lock(&spin);
 289                         spin_unlock(&spin);
 290                 }
 291                 logtest_noargs(spin_end);
 292                 ktr_testspincnt = 0;
 293         }
 294 #endif
 295
 296         /*
 297          * Resynchronize the TSC
 298          */
 299         if (ktr_resynchronize == 0)
 300                 goto done;
 301         if ((cpu_feature & CPUID_TSC) == 0)
 302                 return;
 303
 304         crit_enter();
 305         lwkt_cpusync_init(&cs, smp_active_mask, ktr_resync_remote,
 306                           (void *)(intptr_t)mycpu->gd_cpuid);
 307         lwkt_cpusync_interlock(&cs);
 308         ktr_sync_tsc = rdtsc();
 309         lwkt_cpusync_deinterlock(&cs);
 310         crit_exit();
 311 done:
 312         callout_reset(&ktr_resync_callout, hz / 10, ktr_resync_callback, NULL);
 313 }
 314
 315 /*
 316  * The remote-end of the KTR synchronization protocol runs on all cpus.
 317  * The one we run on the controlling cpu updates its tsc continuously
 318  * until the others have finished syncing (theoretically), but we don't
 319  * loop forever.
 320  *
 321  * This is a bit ad-hoc but we need to avoid livelocking inside an IPI
 322  * callback.  rdtsc() is a synchronizing instruction (I think).
 323  */
 324 static void
 325 ktr_resync_remote(void *arg)
 326 {
 327         globaldata_t gd = mycpu;
 328         int64_t delta;
 329         int i;
 330
 331         if (gd->gd_cpuid == (int)(intptr_t)arg) {
 332                 for (i = 0; i < 2000; ++i)
 333                         ktr_sync_tsc = rdtsc();
 334         } else {
 335                 delta = rdtsc() - ktr_sync_tsc;
 336                 if (tsc_offsets[gd->gd_cpuid] == 0)
 337                         tsc_offsets[gd->gd_cpuid] = delta;
 338                 tsc_offsets[gd->gd_cpuid] =
 339                         (tsc_offsets[gd->gd_cpuid] * 7 + delta) / 8;
 340         }
 341 }
 342
 343 #if KTR_TESTLOG
 344
 345 static
 346 void
 347 ktr_pingpong_remote(void *dummy __unused)
 348 {
 349         int other_cpu;
 350
 351         logtest_noargs(pingpong);
 352         other_cpu = 1 - mycpu->gd_cpuid;
 353         if (ktr_testipicnt_remainder) {
 354                 --ktr_testipicnt_remainder;
 355                 lwkt_send_ipiq_bycpu(other_cpu, ktr_pingpong_remote, NULL);
 356         } else {
 357                 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL);
 358                 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL);
 359                 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL);
 360                 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL);
 361                 lwkt_send_ipiq_bycpu(other_cpu, ktr_pipeline_remote, NULL);
 362         }
 363 }
 364
 365 static
 366 void
 367 ktr_pipeline_remote(void *dummy __unused)
 368 {
 369         logtest_noargs(pipeline);
 370 }
 371
 372 #endif
 373
 374 #else   /* !SMP */
 375
 376 /*
 377  * The resync callback for UP doesn't do anything other then run the test
 378  * log messages.  If test logging is not enabled, don't bother resetting
 379  * the callout.
 380  */
 381 static
 382 void
 383 ktr_resync_callback(void *dummy __unused)
 384 {
 385 #if KTR_TESTLOG
 386         /*
 387          * Test logging
 388          */
 389         if (ktr_testlogcnt) {
 390                 --ktr_testlogcnt;
 391                 cpu_disable_intr();
 392                 logtest(test1);
 393                 logtest(test2);
 394                 logtest(test3);
 395                 logtest_noargs(test4);
 396                 logtest_noargs(test5);
 397                 logtest_noargs(test6);
 398                 cpu_enable_intr();
 399         }
 400         callout_reset(&ktr_resync_callout, hz / 10, ktr_resync_callback, NULL);
 401 #endif
 402 }
 403
 404 #endif
 405
 406 /*
 407  * KTR_WRITE_ENTRY - Primary entry point for kernel trace logging
 408  */
 409
 410 static __inline
 411 void
 412 ktr_write_entry(struct ktr_info *info, const char *file, int line, __va_list va)
 413 {
 414         struct ktr_cpu_core *kcpu;
 415         struct ktr_entry *entry;
 416         int cpu;
 417
 418         cpu = mycpu->gd_cpuid;
 419         kcpu = &ktr_cpu[cpu].core;
 420         if (kcpu->ktr_buf == NULL)
 421                 return;
 422
 423         crit_enter();
 424         entry = kcpu->ktr_buf + (kcpu->ktr_idx & KTR_ENTRIES_MASK);
 425         ++kcpu->ktr_idx;
 426 #ifdef _RDTSC_SUPPORTED_
 427         if (cpu_feature & CPUID_TSC) {
 428 #ifdef SMP
 429                 entry->ktr_timestamp = rdtsc() - tsc_offsets[cpu];
 430 #else
 431                 entry->ktr_timestamp = rdtsc();
 432 #endif
 433         } else
 434 #endif
 435         {
 436                 entry->ktr_timestamp = get_approximate_time_t();
 437         }
 438         entry->ktr_info = info;
 439         entry->ktr_file = file;
 440         entry->ktr_line = line;
 441         crit_exit();
 442         if (info->kf_data_size > KTR_BUFSIZE)
 443                 bcopy(va, entry->ktr_data, KTR_BUFSIZE);
 444         else if (info->kf_data_size)
 445                 bcopy(va, entry->ktr_data, info->kf_data_size);
 446         if (ktr_stacktrace)
 447                 cpu_ktr_caller(entry);
 448 #ifdef KTR_VERBOSE
 449         if (ktr_verbose && info->kf_format) {
 450 #ifdef SMP
 451                 kprintf("cpu%d ", cpu);
 452 #endif
 453                 if (ktr_verbose > 1) {
 454                         kprintf("%s.%d\t", entry->ktr_file, entry->ktr_line);
 455                 }
 456                 kvprintf(info->kf_format, va);
 457                 kprintf("\n");
 458         }
 459 #endif
 460 }
 461
 462 void
 463 ktr_log(struct ktr_info *info, const char *file, int line, ...)
 464 {
 465         __va_list va;
 466
 467         if (panicstr == NULL) {
 468                 __va_start(va, line);
 469                 ktr_write_entry(info, file, line, va);
 470                 __va_end(va);
 471         }
 472 }
 473
 474 #ifdef DDB
 475
 476 #define NUM_LINES_PER_PAGE      19
 477
 478 struct tstate {
 479         int     cur;
 480         int     first;
 481 };
 482
 483 static  int db_ktr_verbose;
 484 static  int db_mach_vtrace(int cpu, struct ktr_entry *kp, int idx);
 485
 486 DB_SHOW_COMMAND(ktr, db_ktr_all)
 487 {
 488         struct ktr_cpu_core *kcpu;
 489         int a_flag = 0;
 490         int c;
 491         int nl = 0;
 492         int i;
 493         struct tstate tstate[MAXCPU];
 494         int printcpu = -1;
 495
 496         for(i = 0; i < ncpus; i++) {
 497                 kcpu = &ktr_cpu[i].core;
 498                 tstate[i].first = -1;
 499                 tstate[i].cur = (kcpu->ktr_idx - 1) & KTR_ENTRIES_MASK;
 500         }
 501         db_ktr_verbose = 0;
 502         while ((c = *(modif++)) != '\0') {
 503                 if (c == 'v') {
 504                         db_ktr_verbose = 1;
 505                 }
 506                 else if (c == 'a') {
 507                         a_flag = 1;
 508                 }
 509                 else if (c == 'c') {
 510                         printcpu = 0;
 511                         while ((c = *(modif++)) != '\0') {
 512                                 if (isdigit(c)) {
 513                                         printcpu *= 10;
 514                                         printcpu += c - '0';
 515                                 }
 516                                 else {
 517                                         modif++;
 518                                         break;
 519                                 }
 520                         }
 521                         modif--;
 522                 }
 523         }
 524         if (printcpu > ncpus - 1) {
 525                 db_printf("Invalid cpu number\n");
 526                 return;
 527         }
 528         /*
 529          * Lopp throug all the buffers and print the content of them, sorted
 530          * by the timestamp.
 531          */
 532         while (1) {
 533                 int counter;
 534                 u_int64_t highest_ts;
 535                 int highest_cpu;
 536                 struct ktr_entry *kp;
 537
 538                 if (a_flag == 1 && cncheckc() != -1)
 539                         return;
 540                 highest_ts = 0;
 541                 highest_cpu = -1;
 542                 /*
 543                  * Find the lowest timestamp
 544                  */
 545                 for (i = 0, counter = 0; i < ncpus; i++) {
 546                         kcpu = &ktr_cpu[i].core;
 547                         if (kcpu->ktr_buf == NULL)
 548                                 continue;
 549                         if (printcpu != -1 && printcpu != i)
 550                                 continue;
 551                         if (tstate[i].cur == -1) {
 552                                 counter++;
 553                                 if (counter == ncpus) {
 554                                         db_printf("--- End of trace buffer ---\n");
 555                                         return;
 556                                 }
 557                                 continue;
 558                         }
 559                         if (kcpu->ktr_buf[tstate[i].cur].ktr_timestamp > highest_ts) {
 560                                 highest_ts = kcpu->ktr_buf[tstate[i].cur].ktr_timestamp;
 561                                 highest_cpu = i;
 562                         }
 563                 }
 564                 if (highest_cpu < 0) {
 565                         db_printf("no KTR data available\n");
 566                         break;
 567                 }
 568                 i = highest_cpu;
 569                 kcpu = &ktr_cpu[i].core;
 570                 kp = &kcpu->ktr_buf[tstate[i].cur];
 571                 if (tstate[i].first == -1)
 572                         tstate[i].first = tstate[i].cur;
 573                 if (--tstate[i].cur < 0)
 574                         tstate[i].cur = KTR_ENTRIES - 1;
 575                 if (tstate[i].first == tstate[i].cur) {
 576                         db_mach_vtrace(i, kp, tstate[i].cur + 1);
 577                         tstate[i].cur = -1;
 578                         continue;
 579                 }
 580                 if (kcpu->ktr_buf[tstate[i].cur].ktr_info == NULL)
 581                         tstate[i].cur = -1;
 582                 if (db_more(&nl) == -1)
 583                         break;
 584                 if (db_mach_vtrace(i, kp, tstate[i].cur + 1) == 0)
 585                         tstate[i].cur = -1;
 586         }
 587 }
 588
 589 static int
 590 db_mach_vtrace(int cpu, struct ktr_entry *kp, int idx)
 591 {
 592         if (kp->ktr_info == NULL)
 593                 return(0);
 594 #ifdef SMP
 595         db_printf("cpu%d ", cpu);
 596 #endif
 597         db_printf("%d: ", idx);
 598         if (db_ktr_verbose) {
 599                 db_printf("%10.10lld %s.%d\t", (long long)kp->ktr_timestamp,
 600                     kp->ktr_file, kp->ktr_line);
 601         }
 602         db_printf("%s\t", kp->ktr_info->kf_name);
 603         db_printf("from(%p,%p) ", kp->ktr_caller1, kp->ktr_caller2);
 604 #ifdef __i386__
 605         if (kp->ktr_info->kf_format)
 606                 db_vprintf(kp->ktr_info->kf_format, (__va_list)kp->ktr_data);
 607 #endif
 608         db_printf("\n");
 609
 610         return(1);
 611 }
 612
 613 #endif  /* DDB */