src/bin/lttng/commands/calibrate.c

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  * Copyright (C) 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License, version 2 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #define _GNU_SOURCE
  20 #include <popt.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <sys/stat.h>
  25 #include <sys/types.h>
  26 #include <unistd.h>
  27 #include <inttypes.h>
  28 #include <ctype.h>
  29 #include <assert.h>
  30
  31 #include <common/mi-lttng.h>
  32
  33 #include "../command.h"
  34
  35 static int opt_event_type;
  36 static int opt_kernel;
  37 static int opt_userspace;
  38 #if 0
  39 /* Not implemented yet */
  40 static char *opt_cmd_name;
  41 static pid_t opt_pid;
  42 #endif
  43
  44 enum {
  45         OPT_HELP = 1,
  46         OPT_TRACEPOINT,
  47         OPT_MARKER,
  48         OPT_PROBE,
  49         OPT_FUNCTION,
  50         OPT_FUNCTION_ENTRY,
  51         OPT_SYSCALL,
  52         OPT_USERSPACE,
  53         OPT_KERNEL,
  54         OPT_LIST_OPTIONS,
  55 };
  56
  57 static struct lttng_handle *handle;
  58 static struct mi_writer *writer;
  59
  60 static struct poptOption long_options[] = {
  61         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  62         {"help",           'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  63 #if 0
  64         /* Not implemented yet */
  65         {"userspace",      'u', POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, &opt_cmd_name, OPT_USERSPACE, 0, 0},
  66         {"pid",            'p', POPT_ARG_INT, &opt_pid, 0, 0, 0},
  67         {"tracepoint",     0,   POPT_ARG_NONE, 0, OPT_TRACEPOINT, 0, 0},
  68         {"marker",         0,   POPT_ARG_NONE, 0, OPT_MARKER, 0, 0},
  69         {"probe",          0,   POPT_ARG_NONE, 0, OPT_PROBE, 0, 0},
  70 #else
  71         {"kernel",         'k', POPT_ARG_NONE, 0, OPT_KERNEL, 0, 0},
  72         {"userspace",      'u', POPT_ARG_NONE, 0, OPT_USERSPACE, 0, 0},
  73         {"function",       0,   POPT_ARG_NONE, 0, OPT_FUNCTION, 0, 0},
  74 #endif
  75 #if 0
  76         /*
  77          * Removed from options to discourage its use. Not in kernel
  78          * tracer anymore.
  79          */
  80         {"function:entry", 0,   POPT_ARG_NONE, 0, OPT_FUNCTION_ENTRY, 0, 0},
  81         {"syscall",        0,   POPT_ARG_NONE, 0, OPT_SYSCALL, 0, 0},
  82 #endif
  83         {"list-options", 0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
  84         {0, 0, 0, 0, 0, 0, 0}
  85 };
  86
  87 /*
  88  * usage
  89  */
  90 static void usage(FILE *ofp)
  91 {
  92         fprintf(ofp, "usage: lttng calibrate [-k|-u] [OPTIONS]\n");
  93         fprintf(ofp, "\n");
  94         fprintf(ofp, "Options:\n");
  95         fprintf(ofp, "  -h, --help               Show this help\n");
  96         fprintf(ofp, "      --list-options       Simple listing of options\n");
  97         fprintf(ofp, "  -k, --kernel             Apply to the kernel tracer\n");
  98         fprintf(ofp, "  -u, --userspace          Apply to the user-space tracer\n");
  99         fprintf(ofp, "\n");
 100         fprintf(ofp, "Calibrate options:\n");
 101         fprintf(ofp, "    --function             Dynamic function entry/return probe (default)\n");
 102 #if 0
 103         fprintf(ofp, "    --tracepoint           Tracepoint event (default)\n");
 104         fprintf(ofp, "    --probe\n");
 105         fprintf(ofp, "                           Dynamic probe.\n");
 106 #if 0
 107         fprintf(ofp, "    --function:entry symbol\n");
 108         fprintf(ofp, "                           Function tracer event\n");
 109 #endif
 110         fprintf(ofp, "    --syscall              System call eventl\n");
 111         fprintf(ofp, "    --marker               User-space marker (deprecated)\n");
 112 #endif
 113         fprintf(ofp, "\n");
 114 }
 115
 116 /*
 117  * Calibrate LTTng.
 118  *
 119  * Returns a CMD_* error.
 120  */
 121 static int calibrate_lttng(void)
 122 {
 123         int ret = CMD_SUCCESS;
 124         struct lttng_domain dom;
 125         struct lttng_calibrate calibrate;
 126
 127         memset(&dom, 0, sizeof(dom));
 128         memset(&calibrate, 0, sizeof(calibrate));
 129
 130         /* Create lttng domain */
 131         if (opt_kernel) {
 132                 dom.type = LTTNG_DOMAIN_KERNEL;
 133         } else if (opt_userspace) {
 134                 dom.type = LTTNG_DOMAIN_UST;
 135         } else {
 136                 /* Checked by the caller. */
 137                 assert(0);
 138         }
 139
 140         handle = lttng_create_handle(NULL, &dom);
 141         if (handle == NULL) {
 142                 ret = CMD_ERROR;
 143                 goto error;
 144         }
 145
 146         switch (opt_event_type) {
 147         case LTTNG_EVENT_TRACEPOINT:
 148                 DBG("Calibrating kernel tracepoints");
 149                 break;
 150         case LTTNG_EVENT_PROBE:
 151                 DBG("Calibrating kernel probes");
 152                 break;
 153         case LTTNG_EVENT_FUNCTION:
 154                 DBG("Calibrating kernel functions");
 155                 calibrate.type = LTTNG_CALIBRATE_FUNCTION;
 156                 ret = lttng_calibrate(handle, &calibrate);
 157                 if (ret < 0) {
 158                         ERR("%s", lttng_strerror(ret));
 159                         goto error;
 160                 }
 161                 MSG("%s calibration done", opt_kernel ? "Kernel" : "UST");
 162                 break;
 163         case LTTNG_EVENT_FUNCTION_ENTRY:
 164                 DBG("Calibrating kernel function entry");
 165                 break;
 166         case LTTNG_EVENT_SYSCALL:
 167                 DBG("Calibrating kernel syscall");
 168                 break;
 169         default:
 170                 ret = CMD_UNDEFINED;
 171                 goto error;
 172         }
 173
 174         if (lttng_opt_mi) {
 175                 assert(writer);
 176                 ret = mi_lttng_calibrate(writer, &calibrate);
 177                 if (ret) {
 178                         ret = CMD_ERROR;
 179                         goto error;
 180                 }
 181         }
 182
 183 error:
 184         lttng_destroy_handle(handle);
 185
 186         return ret;
 187 }
 188
 189 /*
 190  * Calibrate LTTng tracer.
 191  *
 192  * Returns a CMD_* error.
 193  */
 194 int cmd_calibrate(int argc, const char **argv)
 195 {
 196         int opt, ret = CMD_SUCCESS, command_ret = CMD_SUCCESS, success = 1;
 197         static poptContext pc;
 198
 199         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 200         poptReadDefaultConfig(pc, 0);
 201
 202         /* Default event type */
 203         opt_event_type = LTTNG_EVENT_FUNCTION;
 204
 205         while ((opt = poptGetNextOpt(pc)) != -1) {
 206                 switch (opt) {
 207                 case OPT_HELP:
 208                         usage(stdout);
 209                         goto end;
 210                 case OPT_TRACEPOINT:
 211                         ret = CMD_UNDEFINED;
 212                         goto end;
 213                 case OPT_MARKER:
 214                         ret = CMD_UNDEFINED;
 215                         goto end;
 216                 case OPT_PROBE:
 217                         ret = CMD_UNDEFINED;
 218                         break;
 219                 case OPT_FUNCTION:
 220                         opt_event_type = LTTNG_EVENT_FUNCTION;
 221                         break;
 222                 case OPT_FUNCTION_ENTRY:
 223                         ret = CMD_UNDEFINED;
 224                         goto end;
 225                 case OPT_SYSCALL:
 226                         ret = CMD_UNDEFINED;
 227                         goto end;
 228                 case OPT_USERSPACE:
 229                         opt_userspace = 1;
 230                         break;
 231                 case OPT_KERNEL:
 232                         opt_kernel = 1;
 233                         break;
 234                 case OPT_LIST_OPTIONS:
 235                         list_cmd_options(stdout, long_options);
 236                         goto end;
 237                 default:
 238                         usage(stderr);
 239                         ret = CMD_UNDEFINED;
 240                         goto end;
 241                 }
 242         }
 243
 244         ret = print_missing_or_multiple_domains(opt_kernel + opt_userspace);
 245         if (ret) {
 246                 ret = CMD_ERROR;
 247                 goto end;
 248         }
 249
 250         /* Mi check */
 251         if (lttng_opt_mi) {
 252                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 253                 if (!writer) {
 254                         ret = -LTTNG_ERR_NOMEM;
 255                         goto end;
 256                 }
 257
 258                 /* Open command element */
 259                 ret = mi_lttng_writer_command_open(writer,
 260                                 mi_lttng_element_command_calibrate);
 261                 if (ret) {
 262                         ret = CMD_ERROR;
 263                         goto end;
 264                 }
 265
 266                 /* Open output element */
 267                 ret = mi_lttng_writer_open_element(writer,
 268                                 mi_lttng_element_command_output);
 269                 if (ret) {
 270                         ret = CMD_ERROR;
 271                         goto end;
 272                 }
 273         }
 274
 275         command_ret = calibrate_lttng();
 276         if (command_ret) {
 277                 success = 0;
 278         }
 279
 280         /* Mi closing */
 281         if (lttng_opt_mi) {
 282                 /* Close  output element */
 283                 ret = mi_lttng_writer_close_element(writer);
 284                 if (ret) {
 285                         ret = CMD_ERROR;
 286                         goto end;
 287                 }
 288
 289                 /* Success ? */
 290                 ret = mi_lttng_writer_write_element_bool(writer,
 291                                 mi_lttng_element_command_success, success);
 292                 if (ret) {
 293                         ret = CMD_ERROR;
 294                         goto end;
 295                 }
 296
 297                 /* Command element close */
 298                 ret = mi_lttng_writer_command_close(writer);
 299                 if (ret) {
 300                         ret = CMD_ERROR;
 301                         goto end;
 302                 }
 303         }
 304
 305 end:
 306         /* Mi clean-up */
 307         if (writer && mi_lttng_writer_destroy(writer)) {
 308                 /* Preserve original error code */
 309                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 310         }
 311
 312         /* Overwrite ret if an error occurred during calibrate_lttng() */
 313         ret = command_ret ? command_ret : ret;
 314
 315         poptFreeContext(pc);
 316         return ret;
 317 }