sys/kern/kern_ktr.c

   1 /*-
   2  * Copyright (c) 2000 John Baldwin <jhb@FreeBSD.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the author nor the names of any co-contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 /*
  31  * This module holds the global variables used by KTR and the ktr_tracepoint()
  32  * function that does the actual tracing.
  33  */
  34
  35 #include <sys/cdefs.h>
  36 __FBSDID("$FreeBSD$");
  37
  38 #include "opt_ddb.h"
  39 #include "opt_ktr.h"
  40 #include "opt_alq.h"
  41
  42 #include <sys/param.h>
  43 #include <sys/alq.h>
  44 #include <sys/cons.h>
  45 #include <sys/kernel.h>
  46 #include <sys/ktr.h>
  47 #include <sys/libkern.h>
  48 #include <sys/proc.h>
  49 #include <sys/sysctl.h>
  50 #include <sys/systm.h>
  51 #include <sys/time.h>
  52
  53 #include <machine/cpu.h>
  54 #ifdef __sparc64__
  55 #include <machine/ktr.h>
  56 #endif
  57
  58 #ifdef DDB
  59 #include <ddb/ddb.h>
  60 #include <ddb/db_output.h>
  61 #endif
  62
  63 #ifndef KTR_ENTRIES
  64 #define KTR_ENTRIES     1024
  65 #endif
  66
  67 #ifndef KTR_MASK
  68 #define KTR_MASK        (KTR_GEN)
  69 #endif
  70
  71 #ifndef KTR_CPUMASK
  72 #define KTR_CPUMASK     (~0)
  73 #endif
  74
  75 #ifndef KTR_TIME
  76 #define KTR_TIME        get_cyclecount()
  77 #endif
  78
  79 #ifndef KTR_CPU
  80 #define KTR_CPU         PCPU_GET(cpuid)
  81 #endif
  82
  83 SYSCTL_NODE(_debug, OID_AUTO, ktr, CTLFLAG_RD, 0, "KTR options");
  84
  85 int     ktr_cpumask = KTR_CPUMASK;
  86 TUNABLE_INT("debug.ktr.cpumask", &ktr_cpumask);
  87 SYSCTL_INT(_debug_ktr, OID_AUTO, cpumask, CTLFLAG_RW, &ktr_cpumask, 0, "");
  88
  89 int     ktr_mask = KTR_MASK;
  90 TUNABLE_INT("debug.ktr.mask", &ktr_mask);
  91 SYSCTL_INT(_debug_ktr, OID_AUTO, mask, CTLFLAG_RW, &ktr_mask, 0, "");
  92
  93 int     ktr_compile = KTR_COMPILE;
  94 SYSCTL_INT(_debug_ktr, OID_AUTO, compile, CTLFLAG_RD, &ktr_compile, 0, "");
  95
  96 int     ktr_entries = KTR_ENTRIES;
  97 SYSCTL_INT(_debug_ktr, OID_AUTO, entries, CTLFLAG_RD, &ktr_entries, 0, "");
  98
  99 int     ktr_version = KTR_VERSION;
 100 SYSCTL_INT(_debug_ktr, OID_AUTO, version, CTLFLAG_RD, &ktr_version, 0, "");
 101
 102 volatile int    ktr_idx = 0;
 103 struct  ktr_entry ktr_buf[KTR_ENTRIES];
 104
 105 static int
 106 sysctl_debug_ktr_clear(SYSCTL_HANDLER_ARGS)
 107 {
 108         int clear, error;
 109
 110         clear = 0;
 111         error = sysctl_handle_int(oidp, &clear, 0, req);
 112         if (error || !req->newptr)
 113                 return (error);
 114
 115         if (clear) {
 116                 bzero(ktr_buf, sizeof(ktr_buf));
 117                 ktr_idx = 0;
 118         }
 119
 120         return (error);
 121 }
 122 SYSCTL_PROC(_debug_ktr, OID_AUTO, clear, CTLTYPE_INT|CTLFLAG_RW, 0, 0,
 123     sysctl_debug_ktr_clear, "I", "Clear KTR Buffer");
 124
 125 #ifdef KTR_VERBOSE
 126 int     ktr_verbose = KTR_VERBOSE;
 127 TUNABLE_INT("debug.ktr.verbose", &ktr_verbose);
 128 SYSCTL_INT(_debug_ktr, OID_AUTO, verbose, CTLFLAG_RW, &ktr_verbose, 0, "");
 129 #endif
 130
 131 #ifdef KTR_ALQ
 132 struct alq *ktr_alq;
 133 char    ktr_alq_file[MAXPATHLEN] = "/tmp/ktr.out";
 134 int     ktr_alq_cnt = 0;
 135 int     ktr_alq_depth = KTR_ENTRIES;
 136 int     ktr_alq_enabled = 0;
 137 int     ktr_alq_failed = 0;
 138 int     ktr_alq_max = 0;
 139
 140 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_max, CTLFLAG_RW, &ktr_alq_max, 0,
 141     "Maximum number of entries to write");
 142 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_cnt, CTLFLAG_RD, &ktr_alq_cnt, 0,
 143     "Current number of written entries");
 144 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_failed, CTLFLAG_RD, &ktr_alq_failed, 0,
 145     "Number of times we overran the buffer");
 146 SYSCTL_INT(_debug_ktr, OID_AUTO, alq_depth, CTLFLAG_RW, &ktr_alq_depth, 0,
 147     "Number of items in the write buffer");
 148 SYSCTL_STRING(_debug_ktr, OID_AUTO, alq_file, CTLFLAG_RW, ktr_alq_file,
 149     sizeof(ktr_alq_file), "KTR logging file");
 150
 151 static int
 152 sysctl_debug_ktr_alq_enable(SYSCTL_HANDLER_ARGS)
 153 {
 154         int error;
 155         int enable;
 156
 157         enable = ktr_alq_enabled;
 158
 159         error = sysctl_handle_int(oidp, &enable, 0, req);
 160         if (error || !req->newptr)
 161                 return (error);
 162
 163         if (enable) {
 164                 if (ktr_alq_enabled)
 165                         return (0);
 166                 error = alq_open(&ktr_alq, (const char *)ktr_alq_file,
 167                     req->td->td_ucred, ALQ_DEFAULT_CMODE,
 168                     sizeof(struct ktr_entry), ktr_alq_depth);
 169                 if (error == 0) {
 170                         ktr_alq_cnt = 0;
 171                         ktr_alq_failed = 0;
 172                         ktr_alq_enabled = 1;
 173                 }
 174         } else {
 175                 if (ktr_alq_enabled == 0)
 176                         return (0);
 177                 ktr_alq_enabled = 0;
 178                 alq_close(ktr_alq);
 179                 ktr_alq = NULL;
 180         }
 181
 182         return (error);
 183 }
 184 SYSCTL_PROC(_debug_ktr, OID_AUTO, alq_enable,
 185     CTLTYPE_INT|CTLFLAG_RW, 0, 0, sysctl_debug_ktr_alq_enable,
 186     "I", "Enable KTR logging");
 187 #endif
 188
 189 void
 190 ktr_tracepoint(u_int mask, const char *file, int line, const char *format,
 191     u_long arg1, u_long arg2, u_long arg3, u_long arg4, u_long arg5,
 192     u_long arg6)
 193 {
 194         struct ktr_entry *entry;
 195 #ifdef KTR_ALQ
 196         struct ale *ale = NULL;
 197 #else
 198         int newindex, saveindex;
 199 #endif
 200 #if defined(KTR_VERBOSE) || defined(KTR_ALQ)
 201         struct thread *td;
 202 #endif
 203         int cpu;
 204
 205         if (panicstr)
 206                 return;
 207         if ((ktr_mask & mask) == 0)
 208                 return;
 209         cpu = KTR_CPU;
 210         if (((1 << cpu) & ktr_cpumask) == 0)
 211                 return;
 212 #if defined(KTR_VERBOSE) || defined(KTR_ALQ)
 213         td = curthread;
 214         if (td->td_pflags & TDP_INKTR)
 215                 return;
 216         td->td_pflags |= TDP_INKTR;
 217 #endif
 218 #ifdef KTR_ALQ
 219         if (ktr_alq_enabled &&
 220             td->td_critnest == 0 &&
 221             (td->td_flags & TDF_IDLETD) == 0 &&
 222             td != ald_thread) {
 223                 if (ktr_alq_max && ktr_alq_cnt > ktr_alq_max)
 224                         goto done;
 225                 if ((ale = alq_get(ktr_alq, ALQ_NOWAIT)) == NULL) {
 226                         ktr_alq_failed++;
 227                         goto done;
 228                 }
 229                 ktr_alq_cnt++;
 230                 entry = (struct ktr_entry *)ale->ae_data;
 231         } else
 232                 goto done;
 233 #else
 234         do {
 235                 saveindex = ktr_idx;
 236                 newindex = (saveindex + 1) & (KTR_ENTRIES - 1);
 237         } while (atomic_cmpset_rel_int(&ktr_idx, saveindex, newindex) == 0);
 238         entry = &ktr_buf[saveindex];
 239 #endif
 240         entry->ktr_timestamp = KTR_TIME;
 241         entry->ktr_cpu = cpu;
 242         entry->ktr_thread = curthread;
 243         if (file != NULL)
 244                 while (strncmp(file, "../", 3) == 0)
 245                         file += 3;
 246         entry->ktr_file = file;
 247         entry->ktr_line = line;
 248 #ifdef KTR_VERBOSE
 249         if (ktr_verbose) {
 250 #ifdef SMP
 251                 printf("cpu%d ", cpu);
 252 #endif
 253                 if (ktr_verbose > 1) {
 254                         printf("%s.%d\t", entry->ktr_file,
 255                             entry->ktr_line);
 256                 }
 257                 printf(format, arg1, arg2, arg3, arg4, arg5, arg6);
 258                 printf("\n");
 259         }
 260 #endif
 261         entry->ktr_desc = format;
 262         entry->ktr_parms[0] = arg1;
 263         entry->ktr_parms[1] = arg2;
 264         entry->ktr_parms[2] = arg3;
 265         entry->ktr_parms[3] = arg4;
 266         entry->ktr_parms[4] = arg5;
 267         entry->ktr_parms[5] = arg6;
 268 #ifdef KTR_ALQ
 269         if (ale)
 270                 alq_post(ktr_alq, ale);
 271 done:
 272 #endif
 273 #if defined(KTR_VERBOSE) || defined(KTR_ALQ)
 274         td->td_pflags &= ~TDP_INKTR;
 275 #endif
 276 }
 277
 278 #ifdef DDB
 279
 280 struct tstate {
 281         int     cur;
 282         int     first;
 283 };
 284 static  struct tstate tstate;
 285 static  int db_ktr_verbose;
 286 static  int db_mach_vtrace(void);
 287
 288 DB_SHOW_COMMAND(ktr, db_ktr_all)
 289 {
 290
 291         tstate.cur = (ktr_idx - 1) & (KTR_ENTRIES - 1);
 292         tstate.first = -1;
 293         db_ktr_verbose = index(modif, 'v') != NULL;
 294         if (index(modif, 'a') != NULL) {
 295                 db_disable_pager();
 296                 while (cncheckc() != -1)
 297                         if (db_mach_vtrace() == 0)
 298                                 break;
 299         } else {
 300                 while (!db_pager_quit)
 301                         if (db_mach_vtrace() == 0)
 302                                 break;
 303         }
 304 }
 305
 306 static int
 307 db_mach_vtrace(void)
 308 {
 309         struct ktr_entry        *kp;
 310
 311         if (tstate.cur == tstate.first) {
 312                 db_printf("--- End of trace buffer ---\n");
 313                 return (0);
 314         }
 315         kp = &ktr_buf[tstate.cur];
 316
 317         /* Skip over unused entries. */
 318         if (kp->ktr_desc == NULL) {
 319                 db_printf("--- End of trace buffer ---\n");
 320                 return (0);
 321         }
 322         db_printf("%d (%p", tstate.cur, kp->ktr_thread);
 323 #ifdef SMP
 324         db_printf(":cpu%d", kp->ktr_cpu);
 325 #endif
 326         db_printf(")");
 327         if (db_ktr_verbose) {
 328                 db_printf(" %10.10lld %s.%d", (long long)kp->ktr_timestamp,
 329                     kp->ktr_file, kp->ktr_line);
 330         }
 331         db_printf(": ");
 332         db_printf(kp->ktr_desc, kp->ktr_parms[0], kp->ktr_parms[1],
 333             kp->ktr_parms[2], kp->ktr_parms[3], kp->ktr_parms[4],
 334             kp->ktr_parms[5]);
 335         db_printf("\n");
 336
 337         if (tstate.first == -1)
 338                 tstate.first = tstate.cur;
 339
 340         if (--tstate.cur < 0)
 341                 tstate.cur = KTR_ENTRIES - 1;
 342
 343         return (1);
 344 }
 345
 346 #endif  /* DDB */