tests/clock-plugin/lttng-clock-plugin-test.c

   1 /*
   2  * lttng-clock-plugin-test.c
   3  *
   4  * Copyright (C) 2014, 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; only
   9  * version 2.1 of the License.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/ktime.h>
  23 #include <linux/hrtimer.h>
  24 #include <linux/time.h>
  25
  26 #include <lttng-clock.h>        /* From lttng-modules */
  27
  28 static u64 trace_clock_read64_example(void)
  29 {
  30         /* Freeze time. */
  31         return 0;
  32 }
  33
  34 static u64 trace_clock_freq_example(void)
  35 {
  36         return 1000;    /* 1KHz */
  37 }
  38
  39 static int trace_clock_uuid_example(char *uuid)
  40 {
  41         const char myuuid[] = "83c63deb-7aa4-48fb-abda-946f400d76e6";
  42         memcpy(uuid, myuuid, LTTNG_MODULES_UUID_STR_LEN);
  43         return 0;
  44 }
  45
  46 static const char *trace_clock_name_example(void)
  47 {
  48         return "lttng_test_clock_override";
  49 }
  50
  51 static const char *trace_clock_description_example(void)
  52 {
  53         return "Freeze time with 1KHz for regression test";
  54 }
  55
  56 static
  57 struct lttng_trace_clock ltc = {
  58         .read64 = trace_clock_read64_example,
  59         .freq = trace_clock_freq_example,
  60         .uuid = trace_clock_uuid_example,
  61         .name = trace_clock_name_example,
  62         .description = trace_clock_description_example,
  63 };
  64
  65 static __init
  66 int lttng_clock_plugin_init(void)
  67 {
  68         return lttng_clock_register_plugin(&ltc, THIS_MODULE);
  69 }
  70 fs_initcall(lttng_clock_plugin_init);
  71
  72 static __exit
  73 void lttng_clock_plugin_exit(void)
  74 {
  75         lttng_clock_unregister_plugin(&ltc, THIS_MODULE);
  76 }
  77 module_exit(lttng_clock_plugin_exit);
  78
  79 MODULE_LICENSE("GPL and additional rights");
  80 MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
  81 MODULE_DESCRIPTION("LTTng Clock Plugin Example");