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-tracer.h>
  27 #include <lttng-clock.h>        /* From lttng-modules */
  28
  29 static u64 trace_clock_read64_example(void)
  30 {
  31         /* Freeze time. */
  32         return 0;
  33 }
  34
  35 static u64 trace_clock_freq_example(void)
  36 {
  37         return 1000;    /* 1KHz */
  38 }
  39
  40 static int trace_clock_uuid_example(char *uuid)
  41 {
  42         const char myuuid[] = "83c63deb-7aa4-48fb-abda-946f400d76e6";
  43         memcpy(uuid, myuuid, LTTNG_MODULES_UUID_STR_LEN);
  44         return 0;
  45 }
  46
  47 static const char *trace_clock_name_example(void)
  48 {
  49         return "lttng_test_clock_override";
  50 }
  51
  52 static const char *trace_clock_description_example(void)
  53 {
  54         return "Freeze time with 1KHz for regression test";
  55 }
  56
  57 static
  58 struct lttng_trace_clock ltc = {
  59         .read64 = trace_clock_read64_example,
  60         .freq = trace_clock_freq_example,
  61         .uuid = trace_clock_uuid_example,
  62         .name = trace_clock_name_example,
  63         .description = trace_clock_description_example,
  64 };
  65
  66 static __init
  67 int lttng_clock_plugin_init(void)
  68 {
  69         return lttng_clock_register_plugin(&ltc, THIS_MODULE);
  70 }
  71 fs_initcall(lttng_clock_plugin_init);
  72
  73 static __exit
  74 void lttng_clock_plugin_exit(void)
  75 {
  76         lttng_clock_unregister_plugin(&ltc, THIS_MODULE);
  77 }
  78 module_exit(lttng_clock_plugin_exit);
  79
  80 MODULE_LICENSE("GPL and additional rights");
  81 MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
  82 MODULE_DESCRIPTION("LTTng Clock Plugin Example");
  83 MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
  84         __stringify(LTTNG_MODULES_MINOR_VERSION) "."
  85         __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
  86         LTTNG_MODULES_EXTRAVERSION);