doc/examples/getcpu-override/lttng-ust-getcpu-override-example.c

   1 /*
   2  * lttng-getcpu-override-example.c
   3  *
   4  * Copyright (c) 2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22  * SOFTWARE.
  23  */
  24
  25 #include <stdlib.h>
  26 #include <time.h>
  27 #include <string.h>
  28 #include <stdio.h>
  29 #include <lttng/ust-getcpu.h>
  30
  31 static
  32 int plugin_getcpu(void)
  33 {
  34         /* Dummy: always return CPU 0. */
  35         return 0;
  36 }
  37
  38 void lttng_ust_getcpu_plugin_init(void)
  39 {
  40         int ret;
  41
  42         ret = lttng_ust_getcpu_override(plugin_getcpu);
  43         if (ret) {
  44                 fprintf(stderr, "Error enabling getcpu override: %s\n",
  45                         strerror(-ret));
  46                 goto error;
  47         }
  48         return;
  49
  50 error:
  51         exit(EXIT_FAILURE);
  52 }