lttng/commands/enable_events.c

   1 /*
   2  * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; only version 2
   7  * of the License.
   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
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, 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
  29 #include "../cmd.h"
  30 #include "../conf.h"
  31 #include "../utils.h"
  32
  33 static char *opt_event_list;
  34 static int opt_event_type;
  35 static char *opt_kernel;
  36 static char *opt_cmd_name;
  37 static char *opt_session_name;
  38 static int opt_pid_all;
  39 static int opt_userspace;
  40 static int opt_enable_all;
  41 static pid_t opt_pid;
  42 static char *opt_probe;
  43 static char *opt_function_symbol;
  44 static char *opt_channel_name;
  45
  46 enum {
  47         OPT_HELP = 1,
  48         OPT_USERSPACE,
  49         OPT_TRACEPOINT,
  50         OPT_MARKER,
  51         OPT_PROBE,
  52         OPT_FUNCTION,
  53 };
  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         {"session",        's', POPT_ARG_STRING, &opt_session_name, 0, 0, 0},
  59         {"all-events",     'a', POPT_ARG_VAL, &opt_enable_all, 1, 0, 0},
  60         {"channel",        'c', POPT_ARG_STRING, &opt_channel_name, 0, 0, 0},
  61         {"kernel",         'k', POPT_ARG_VAL, &opt_kernel, 1, 0, 0},
  62         {"userspace",      'u', POPT_ARG_STRING | POPT_ARGFLAG_OPTIONAL, 0, OPT_USERSPACE, 0, 0},
  63         {"all",            0,   POPT_ARG_VAL, &opt_pid_all, 1, 0, 0},
  64         {"pid",            'p', POPT_ARG_INT, &opt_pid, 0, 0, 0},
  65         {"tracepoint",     0,   POPT_ARG_NONE, 0, OPT_TRACEPOINT, 0, 0},
  66         {"marker",         0,   POPT_ARG_NONE, 0, OPT_MARKER, 0, 0},
  67         {"probe",         0,   POPT_ARG_STRING, 0, OPT_PROBE, 0, 0},
  68         {"function",       0,   POPT_ARG_STRING, 0, OPT_FUNCTION, 0, 0},
  69         {0, 0, 0, 0, 0, 0, 0}
  70 };
  71
  72 /*
  73  * usage
  74  */
  75 static void usage(FILE *ofp)
  76 {
  77         fprintf(ofp, "usage: lttng enable-event NAME[,NAME2,...] [options] [event_options]\n");
  78         fprintf(ofp, "\n");
  79         fprintf(ofp, "  -h, --help               Show this help\n");
  80         fprintf(ofp, "  -s, --session            Apply on session name\n");
  81         fprintf(ofp, "  -c, --channel            Apply on this channel\n");
  82         fprintf(ofp, "  -a, --all-events         Enable all tracepoints\n");
  83         fprintf(ofp, "  -k, --kernel             Apply for the kernel tracer\n");
  84         fprintf(ofp, "  -u, --userspace [CMD]    Apply for the user-space tracer\n");
  85         fprintf(ofp, "      --all                If -u, apply on all traceable apps\n");
  86         fprintf(ofp, "  -p, --pid PID            If -u, apply on a specific PID\n");
  87         fprintf(ofp, "\n");
  88         fprintf(ofp, "Event options:\n");
  89         fprintf(ofp, "    --tracepoint           Tracepoint event (default)\n");
  90         fprintf(ofp, "    --probe [addr | symbol+offset]\n");
  91         fprintf(ofp, "                           Dynamic probe.\n");
  92         fprintf(ofp, "                           Addr and offset can be octal (0NNN...),\n");
  93         fprintf(ofp, "                           decimal (NNN...) or hexadecimal (0xNNN...)\n");
  94         fprintf(ofp, "    --function SYMBOL      Function tracer event\n");
  95         fprintf(ofp, "    --marker               User-space marker (deprecated)\n");
  96         fprintf(ofp, "\n");
  97 }
  98
  99 /*
 100  *  parse_probe_addr
 101  *
 102  *  Parse probe options.
 103  */
 104 static int parse_probe_opts(struct lttng_event *ev, char *opt)
 105 {
 106         int ret;
 107         char s_hex[19];
 108         char name[LTTNG_SYMBOL_NAME_LEN];
 109
 110         if (opt == NULL) {
 111                 ret = -1;
 112                 goto error;
 113         }
 114
 115         /* Check for symbol+offset */
 116         ret = sscanf(opt, "%[^'+']+%s", name, s_hex);
 117         if (ret == 2) {
 118                 strncpy(ev->attr.probe.symbol_name, name, LTTNG_SYMBOL_NAME_LEN);
 119                 DBG("probe symbol %s", ev->attr.probe.symbol_name);
 120                 if (strlen(s_hex) == 0) {
 121                         ERR("Invalid probe offset %s", s_hex);
 122                         ret = -1;
 123                         goto error;
 124                 }
 125                 ev->attr.probe.offset = strtoul(s_hex, NULL, 0);
 126                 DBG("probe offset %" PRIu64, ev->attr.probe.offset);
 127                 ev->attr.probe.addr = 0;
 128                 goto error;
 129         }
 130
 131         /* Check for address */
 132         ret = sscanf(opt, "%s", s_hex);
 133         if (ret > 0) {
 134                 if (strlen(s_hex) == 0) {
 135                         ERR("Invalid probe address %s", s_hex);
 136                         ret = -1;
 137                         goto error;
 138                 }
 139                 ev->attr.probe.addr = strtoul(s_hex, NULL, 0);
 140                 DBG("probe addr %" PRIu64, ev->attr.probe.addr);
 141                 ev->attr.probe.offset = 0;
 142                 memset(ev->attr.probe.symbol_name, 0, LTTNG_SYMBOL_NAME_LEN);
 143                 goto error;
 144         }
 145
 146         /* No match */
 147         ret = -1;
 148
 149 error:
 150         return ret;
 151 }
 152
 153 /*
 154  *  enable_events
 155  *
 156  *  Enabling event using the lttng API.
 157  */
 158 static int enable_events(void)
 159 {
 160         int err, ret = CMD_SUCCESS;
 161         char *event_name, *channel_name = NULL;
 162         struct lttng_event ev;
 163         struct lttng_domain dom;
 164
 165         if (set_session_name(opt_session_name) < 0) {
 166                 ret = CMD_ERROR;
 167                 goto error;
 168         }
 169
 170         if (opt_channel_name == NULL) {
 171                 err = asprintf(&channel_name, DEFAULT_CHANNEL_NAME);
 172                 if (err < 0) {
 173                         ret = CMD_FATAL;
 174                         goto error;
 175                 }
 176         } else {
 177                 channel_name = opt_channel_name;
 178         }
 179
 180         /* Create lttng domain */
 181         if (opt_kernel) {
 182                 dom.type = LTTNG_DOMAIN_KERNEL;
 183         }
 184
 185         if (opt_enable_all) {
 186                 if (opt_kernel) {
 187                         ret = lttng_enable_event(&dom, NULL, channel_name);
 188                         if (ret == 0) {
 189                                 MSG("All kernel events are enabled in channel %s", channel_name);
 190                         }
 191                         goto error;
 192                 }
 193
 194                 /* TODO: User-space tracer */
 195         }
 196
 197         /* Strip event list */
 198         event_name = strtok(opt_event_list, ",");
 199         while (event_name != NULL) {
 200                 /* Kernel tracer action */
 201                 if (opt_kernel) {
 202                         DBG("Enabling kernel event %s for channel %s",
 203                                         event_name, channel_name);
 204                         /* Copy name and type of the event */
 205                         strncpy(ev.name, event_name, LTTNG_SYMBOL_NAME_LEN);
 206                         ev.type = opt_event_type;
 207
 208                         switch (opt_event_type) {
 209                         case LTTNG_EVENT_TRACEPOINT:
 210                                 break;
 211                         case LTTNG_EVENT_PROBE:
 212                                 ret = parse_probe_opts(&ev, opt_probe);
 213                                 if (ret < 0) {
 214                                         ERR("Unable to parse probe options");
 215                                         ret = 0;
 216                                         goto error;
 217                                 }
 218                                 break;
 219                         case LTTNG_EVENT_FUNCTION:
 220                                 strncpy(ev.attr.ftrace.symbol_name, opt_function_symbol, LTTNG_SYMBOL_NAME_LEN);
 221                                 break;
 222                         default:
 223                                 ret = CMD_NOT_IMPLEMENTED;
 224                                 goto error;
 225                         }
 226
 227                         ret = lttng_enable_event(&dom, &ev, channel_name);
 228                         if (ret == 0) {
 229                                 MSG("Kernel event %s created in channel %s", event_name, channel_name);
 230                         }
 231                 } else if (opt_userspace) {             /* User-space tracer action */
 232                         /*
 233                          * TODO: Waiting on lttng UST 2.0
 234                          */
 235                         if (opt_pid_all) {
 236                         } else if (opt_pid != 0) {
 237                         }
 238                         ret = CMD_NOT_IMPLEMENTED;
 239                         goto error;
 240                 } else {
 241                         ERR("Please specify a tracer (kernel or user-space)");
 242                         goto error;
 243                 }
 244
 245                 /* Next event */
 246                 event_name = strtok(NULL, ",");
 247         }
 248
 249 error:
 250         if (opt_channel_name == NULL) {
 251                 free(channel_name);
 252         }
 253         return ret;
 254 }
 255
 256 /*
 257  *  cmd_enable_events
 258  *
 259  *  Add event to trace session
 260  */
 261 int cmd_enable_events(int argc, const char **argv)
 262 {
 263         int opt, ret;
 264         static poptContext pc;
 265
 266         pc = poptGetContext(NULL, argc, argv, long_options, 0);
 267         poptReadDefaultConfig(pc, 0);
 268
 269         /* Default event type */
 270         opt_event_type = LTTNG_EVENT_TRACEPOINT;
 271
 272         while ((opt = poptGetNextOpt(pc)) != -1) {
 273                 switch (opt) {
 274                 case OPT_HELP:
 275                         usage(stderr);
 276                         ret = CMD_SUCCESS;
 277                         goto end;
 278                 case OPT_USERSPACE:
 279                         opt_userspace = 1;
 280                         opt_cmd_name = poptGetOptArg(pc);
 281                         break;
 282                 case OPT_TRACEPOINT:
 283                         opt_event_type = LTTNG_EVENT_TRACEPOINT;
 284                         break;
 285                 case OPT_MARKER:
 286                         ret = CMD_NOT_IMPLEMENTED;
 287                         goto end;
 288                 case OPT_PROBE:
 289                         opt_event_type = LTTNG_EVENT_PROBE;
 290                         opt_probe = poptGetOptArg(pc);
 291                         break;
 292                 case OPT_FUNCTION:
 293                         opt_event_type = LTTNG_EVENT_FUNCTION;
 294                         opt_function_symbol = poptGetOptArg(pc);
 295                         break;
 296                 default:
 297                         usage(stderr);
 298                         ret = CMD_UNDEFINED;
 299                         goto end;
 300                 }
 301         }
 302
 303         opt_event_list = (char*) poptGetArg(pc);
 304         if (opt_event_list == NULL && opt_enable_all == 0) {
 305                 ERR("Missing event name(s).\n");
 306                 usage(stderr);
 307                 ret = CMD_SUCCESS;
 308                 goto end;
 309         }
 310
 311         ret = enable_events();
 312
 313 end:
 314         return ret;
 315 }