tests/lttng/kernel_event_basic.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 modify
   5  * it under the terms of the GNU General Public License as published by
   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 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 <assert.h>
  21 #include <errno.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <unistd.h>
  26 #include <time.h>
  27
  28 #include <lttng/lttng.h>
  29
  30 #include "../utils.h"
  31
  32 int main(int argc, char **argv)
  33 {
  34     struct lttng_handle *handle = NULL;
  35     struct lttng_domain dom;
  36         struct lttng_channel channel;
  37         struct lttng_event sched_switch;
  38         struct lttng_event sched_process_exit;
  39         struct lttng_event sched_process_free;
  40
  41     int ret = 0;
  42
  43         char *session_name = "kernel_event";
  44
  45     dom.type = LTTNG_DOMAIN_KERNEL;
  46
  47         strcpy(channel.name, "mychan");
  48         channel.attr.overwrite = 0;
  49         channel.attr.subbuf_size = 4096;
  50         channel.attr.num_subbuf = 8;
  51         channel.attr.switch_timer_interval = 0;
  52         channel.attr.read_timer_interval = 200;
  53         channel.attr.output = LTTNG_EVENT_SPLICE;
  54
  55         strcpy(sched_switch.name, "sched_switch");
  56         sched_switch.type = LTTNG_EVENT_TRACEPOINT;
  57
  58         strcpy(sched_process_exit.name, "sched_process_exit");
  59         sched_process_exit.type = LTTNG_EVENT_TRACEPOINT;
  60
  61         strcpy(sched_process_free.name, "sched_process_free");
  62         sched_process_free.type = LTTNG_EVENT_TRACEPOINT;
  63
  64         printf("\nTesting tracing kernel events:\n");
  65         printf("-----------\n");
  66         /* Check if root */
  67         if (getuid() != 0) {
  68                 printf("Root access is needed.\nPlease run 'sudo make check' -- Aborting!\n");
  69                 return 0;
  70         }
  71
  72         if (argc < 2) {
  73                 printf("Missing session trace path\n");
  74                 return 1;
  75         }
  76
  77         printf("Creating tracing session (%s): ", argv[1]);
  78     if ((ret = lttng_create_session(session_name, argv[1])) < 0) {
  79         printf("error creating the session : %s\n", lttng_strerror(ret));
  80                 goto create_fail;
  81     }
  82         PRINT_OK();
  83
  84         printf("Creating session handle: ");
  85         if ((handle = lttng_create_handle(session_name, &dom)) == NULL) {
  86                 printf("error creating handle: %s\n", lttng_strerror(ret));
  87                 goto handle_fail;
  88         }
  89         PRINT_OK();
  90
  91         printf("Enabling %s kernel channel: ", channel.name);
  92         if ((ret = lttng_enable_channel(handle, &channel)) < 0) {
  93                 printf("error enable channel: %s\n", lttng_strerror(ret));
  94                 goto enable_fail;
  95         }
  96
  97         printf("Enabling %s kernel event: ", sched_switch.name);
  98     if ((ret = lttng_enable_event(handle, &sched_switch, channel.name)) < 0) {
  99         printf("error enabling event: %s\n", lttng_strerror(ret));
 100                 goto enable_fail;
 101     }
 102         PRINT_OK();
 103
 104         printf("Enabling %s kernel event: ", sched_process_exit.name);
 105         if ((ret = lttng_enable_event(handle, &sched_process_exit, channel.name)) < 0) {
 106                 printf("error enabling event: %s\n", lttng_strerror(ret));
 107                 goto enable_fail;
 108         }
 109         PRINT_OK();
 110
 111         printf("Enabling %s kernel event: ", sched_process_free.name);
 112         if ((ret = lttng_enable_event(handle, &sched_process_free, channel.name)) < 0) {
 113                 printf("error enabling event: %s\n", lttng_strerror(ret));
 114                 goto enable_fail;
 115         }
 116         PRINT_OK();
 117
 118         printf("Disabling %s kernel event: ", sched_switch.name);
 119         if ((ret = lttng_disable_event(handle, sched_switch.name, channel.name)) < 0) {
 120                 printf("error enabling event: %s\n", lttng_strerror(ret));
 121                 goto enable_fail;
 122         }
 123         PRINT_OK();
 124
 125         printf("Disabling %s kernel event: ", sched_process_free.name);
 126         if ((ret = lttng_disable_event(handle, sched_process_free.name, channel.name)) < 0) {
 127                 printf("error enabling event: %s\n", lttng_strerror(ret));
 128                 goto enable_fail;
 129         }
 130         PRINT_OK();
 131
 132         printf("Renabling %s kernel event: ", sched_switch.name);
 133         if ((ret = lttng_enable_event(handle, &sched_switch, channel.name)) < 0) {
 134                 printf("error enabling event: %s\n", lttng_strerror(ret));
 135                 goto enable_fail;
 136         }
 137         PRINT_OK();
 138
 139         printf("Renabling %s kernel event: ", sched_process_free.name);
 140         if ((ret = lttng_enable_event(handle, &sched_process_free, channel.name)) < 0) {
 141                 printf("error enabling event: %s\n", lttng_strerror(ret));
 142                 goto enable_fail;
 143         }
 144         PRINT_OK();
 145
 146         printf("Start tracing: ");
 147         if ((ret = lttng_start_tracing(handle)) < 0) {
 148                 printf("error starting tracing: %s\n", lttng_strerror(ret));
 149                 goto start_fail;
 150         }
 151         PRINT_OK();
 152
 153         sleep(2);
 154
 155         printf("Stop tracing: ");
 156         if ((ret = lttng_stop_tracing(handle)) < 0) {
 157                 printf("error stopping tracing: %s\n", lttng_strerror(ret));
 158                 goto stop_fail;
 159         }
 160         PRINT_OK();
 161
 162         printf("Destroy tracing session: ");
 163         if ((ret = lttng_destroy_session(session_name)) < 0) {
 164                 printf("error destroying session: %s\n", lttng_strerror(ret));
 165         }
 166         PRINT_OK();
 167
 168         return 0;
 169
 170 create_fail:
 171         assert(ret != 0);
 172 handle_fail:
 173         assert(handle != NULL);
 174
 175 stop_fail:
 176 start_fail:
 177 enable_fail:
 178         lttng_destroy_session(session_name);
 179         lttng_destroy_handle(handle);
 180
 181     return 1;
 182 }