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