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 #define _LGPL_SOURCE
  21 #include <popt.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <sys/stat.h>
  26 #include <sys/types.h>
  27 #include <unistd.h>
  28 #include <inttypes.h>
  29 #include <ctype.h>
  30 #include <assert.h>
  31
  32 #include <common/mi-lttng.h>
  33
  34 #include "../command.h"
  35
  36 static int opt_event_type;
  37 static int opt_kernel;
  38 static int opt_userspace;
  39
  40 enum {
  41         OPT_HELP = 1,
  42         OPT_TRACEPOINT,
  43         OPT_MARKER,
  44         OPT_PROBE,
  45         OPT_FUNCTION,
  46         OPT_FUNCTION_ENTRY,
  47         OPT_SYSCALL,
  48         OPT_USERSPACE,
  49         OPT_KERNEL,
  50         OPT_LIST_OPTIONS,
  51 };
  52
  53 static struct lttng_handle *handle;
  54 static struct mi_writer *writer;
  55
  56 static struct poptOption long_options[] = {
  57         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  58         {"help",           'h', POPT_ARG_NONE, 0, OPT_HELP, 0, 0},
  59         {"kernel",         'k', POPT_ARG_NONE, 0, OPT_KERNEL, 0, 0},
  60         {"userspace",      'u', POPT_ARG_NONE, 0, OPT_USERSPACE, 0, 0},
  61         {"function",       0,   POPT_ARG_NONE, 0, OPT_FUNCTION, 0, 0},
  62         {"list-options", 0, POPT_ARG_NONE, NULL, OPT_LIST_OPTIONS, NULL, NULL},
  63         {0, 0, 0, 0, 0, 0, 0}
  64 };
  65
  66 /*
  67  * usage
  68  */
  69 static void usage(FILE *ofp)
  70 {
  71         fprintf(ofp, "usage: lttng calibrate [-k|-u] [OPTIONS]\n");
  72         fprintf(ofp, "\n");
  73         fprintf(ofp, "Options:\n");
  74         fprintf(ofp, "  -h, --help               Show this help\n");
  75         fprintf(ofp, "      --list-options       Simple listing of options\n");
  76         fprintf(ofp, "  -k, --kernel             Apply to the kernel tracer\n");
  77         fprintf(ofp, "  -u, --userspace          Apply to the user-space tracer\n");
  78         fprintf(ofp, "\n");
  79         fprintf(ofp, "Calibrate options:\n");
  80         fprintf(ofp, "    --function             Dynamic function entry/return probe (default)\n");
  81         fprintf(ofp, "\n");
  82 }
  83
  84 /*
  85  * Calibrate LTTng.
  86  *
  87  * Returns a CMD_* error.
  88  */
  89 static int calibrate_lttng(void)
  90 {
  91         int ret = CMD_SUCCESS;
  92         struct lttng_domain dom;
  93         struct lttng_calibrate calibrate;
  94
  95         memset(&dom, 0, sizeof(dom));
  96         memset(&calibrate, 0, sizeof(calibrate));
  97
  98         /* Create lttng domain */
  99         if (opt_kernel) {
 100                 dom.type = LTTNG_DOMAIN_KERNEL;
 101         } else if (opt_userspace) {
 102                 dom.type = LTTNG_DOMAIN_UST;
 103         } else {
 104                 /* Checked by the caller. */
 105                 assert(0);
 106         }
 107
 108         handle = lttng_create_handle(NULL, &dom);
 109         if (handle == NULL) {
 110                 ret = CMD_ERROR;
 111                 goto error;
 112         }
 113
 114         switch (opt_event_type) {
 115         case LTTNG_EVENT_TRACEPOINT:
 116                 DBG("Calibrating kernel tracepoints");
 117                 break;
 118         case LTTNG_EVENT_PROBE:
 119                 DBG("Calibrating kernel probes");
 120                 break;
 121         case LTTNG_EVENT_FUNCTION:
 122                 DBG("Calibrating kernel functions");
 123                 calibrate.type = LTTNG_CALIBRATE_FUNCTION;
 124                 ret = lttng_calibrate(handle, &calibrate);
 125                 if (ret < 0) {
 126                         ERR("%s", lttng_strerror(ret));
 127                         goto error;
 128                 }
 129                 MSG("%s calibration done", opt_kernel ? "Kernel" : "UST");
 130                 break;
 131         case LTTNG_EVENT_FUNCTION_ENTRY:
 132                 DBG("Calibrating kernel function entry");
 133                 break;
 134         case LTTNG_EVENT_SYSCALL:
 135                 DBG("Calibrating kernel syscall");
 136                 break;
 137         default:
 138                 ret = CMD_UNDEFINED;
 139                 goto error;
 140         }
 141
 142         if (lttng_opt_mi) {
 143                 assert(writer);
 144                 ret = mi_lttng_calibrate(writer, &calibrate);
 145                 if (ret) {
 146                         ret = CMD_ERROR;
 147                         goto error;
 148                 }
 149         }
 150
 151 error:
 152         lttng_destroy_handle(handle);
 153
 154         return ret;
 155 }
 156
 157 /*
 158  * Calibrate LTTng tracer.
 159  *
 160  * Returns a CMD_* error.
 161  */
 162 int cmd_calibrate(int argc, const char **argv)
 163 {
 164         int opt, ret = CMD_SUCCESS, command_ret = CMD_SUCCESS, success = 1;
 165         static poptContext pc;
 166
 167         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 168         poptReadDefaultConfig(pc, 0);
 169
 170         /* Default event type */
 171         opt_event_type = LTTNG_EVENT_FUNCTION;
 172
 173         while ((opt = poptGetNextOpt(pc)) != -1) {
 174                 switch (opt) {
 175                 case OPT_HELP:
 176                         usage(stdout);
 177                         goto end;
 178                 case OPT_TRACEPOINT:
 179                         ret = CMD_UNDEFINED;
 180                         goto end;
 181                 case OPT_MARKER:
 182                         ret = CMD_UNDEFINED;
 183                         goto end;
 184                 case OPT_PROBE:
 185                         ret = CMD_UNDEFINED;
 186                         break;
 187                 case OPT_FUNCTION:
 188                         opt_event_type = LTTNG_EVENT_FUNCTION;
 189                         break;
 190                 case OPT_FUNCTION_ENTRY:
 191                         ret = CMD_UNDEFINED;
 192                         goto end;
 193                 case OPT_SYSCALL:
 194                         ret = CMD_UNDEFINED;
 195                         goto end;
 196                 case OPT_USERSPACE:
 197                         opt_userspace = 1;
 198                         break;
 199                 case OPT_KERNEL:
 200                         opt_kernel = 1;
 201                         break;
 202                 case OPT_LIST_OPTIONS:
 203                         list_cmd_options(stdout, long_options);
 204                         goto end;
 205                 default:
 206                         usage(stderr);
 207                         ret = CMD_UNDEFINED;
 208                         goto end;
 209                 }
 210         }
 211
 212         ret = print_missing_or_multiple_domains(opt_kernel + opt_userspace);
 213         if (ret) {
 214                 ret = CMD_ERROR;
 215                 goto end;
 216         }
 217
 218         /* Mi check */
 219         if (lttng_opt_mi) {
 220                 writer = mi_lttng_writer_create(fileno(stdout), lttng_opt_mi);
 221                 if (!writer) {
 222                         ret = -LTTNG_ERR_NOMEM;
 223                         goto end;
 224                 }
 225
 226                 /* Open command element */
 227                 ret = mi_lttng_writer_command_open(writer,
 228                                 mi_lttng_element_command_calibrate);
 229                 if (ret) {
 230                         ret = CMD_ERROR;
 231                         goto end;
 232                 }
 233
 234                 /* Open output element */
 235                 ret = mi_lttng_writer_open_element(writer,
 236                                 mi_lttng_element_command_output);
 237                 if (ret) {
 238                         ret = CMD_ERROR;
 239                         goto end;
 240                 }
 241         }
 242
 243         command_ret = calibrate_lttng();
 244         if (command_ret) {
 245                 success = 0;
 246         }
 247
 248         /* Mi closing */
 249         if (lttng_opt_mi) {
 250                 /* Close  output element */
 251                 ret = mi_lttng_writer_close_element(writer);
 252                 if (ret) {
 253                         ret = CMD_ERROR;
 254                         goto end;
 255                 }
 256
 257                 /* Success ? */
 258                 ret = mi_lttng_writer_write_element_bool(writer,
 259                                 mi_lttng_element_command_success, success);
 260                 if (ret) {
 261                         ret = CMD_ERROR;
 262                         goto end;
 263                 }
 264
 265                 /* Command element close */
 266                 ret = mi_lttng_writer_command_close(writer);
 267                 if (ret) {
 268                         ret = CMD_ERROR;
 269                         goto end;
 270                 }
 271         }
 272
 273 end:
 274         /* Mi clean-up */
 275         if (writer && mi_lttng_writer_destroy(writer)) {
 276                 /* Preserve original error code */
 277                 ret = ret ? ret : -LTTNG_ERR_MI_IO_FAIL;
 278         }
 279
 280         /* Overwrite ret if an error occurred during calibrate_lttng() */
 281         ret = command_ret ? command_ret : ret;
 282
 283         poptFreeContext(pc);
 284         return ret;
 285 }