include/lttng/ust-clock.h

   1 /*
   2  * SPDX-License-Identifier: LGPL-2.1-only
   3  *
   4  * Copyright (C) 2014  Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  */
   6
   7 #ifndef LTTNG_UST_CLOCK_H
   8 #define LTTNG_UST_CLOCK_H
   9
  10 #include <stdint.h>
  11 #include <stddef.h>
  12 #include <lttng/ust-config.h>
  13
  14 #ifdef __cplusplus
  15 extern "C" {
  16 #endif
  17
  18 /*
  19  * Set each callback for the trace clock override, and then enable the
  20  * override. Those functions return negative error values on error, 0 on
  21  * success.
  22  */
  23
  24 typedef uint64_t (*lttng_ust_clock_read64_function)(void);
  25 typedef uint64_t (*lttng_ust_clock_freq_function)(void);
  26 typedef int (*lttng_ust_clock_uuid_function)(char *uuid);
  27 typedef const char *(*lttng_ust_clock_name_function)(void);
  28 typedef const char *(*lttng_ust_clock_description_function)(void);
  29
  30 /* Custom upgrade 2.12 to 2.13 */
  31
  32 #ifndef LTTNG_UST_CUSTOM_UPGRADE_CONFLICTING_SYMBOLS
  33 #define lttng_ust_trace_clock_set_read64_cb             lttng_ust_trace_clock_set_read64_cb1
  34 #define lttng_ust_trace_clock_set_freq_cb               lttng_ust_trace_clock_set_freq_cb1
  35 #define lttng_ust_trace_clock_set_uuid_cb               lttng_ust_trace_clock_set_uuid_cb1
  36 #define lttng_ust_trace_clock_set_name_cb               lttng_ust_trace_clock_set_name_cb1
  37 #define lttng_ust_trace_clock_set_description_cb        lttng_ust_trace_clock_set_description_cb1
  38 #define lttng_ust_enable_trace_clock_override           lttng_ust_enable_trace_clock_override1
  39 #endif
  40
  41 /*
  42  * Set/Get clock override read callback. This callback should return the
  43  * current clock time (a 64-bit monotonic counter).
  44  */
  45 int lttng_ust_trace_clock_set_read64_cb(lttng_ust_clock_read64_function read64_cb);
  46 int lttng_ust_trace_clock_get_read64_cb(lttng_ust_clock_read64_function *read64_cb);
  47
  48 /*
  49  * Set/Get clock override frequency callback. This callback should return
  50  * the frequency of the clock in cycles per second.
  51  */
  52 int lttng_ust_trace_clock_set_freq_cb(lttng_ust_clock_freq_function freq_cb);
  53 int lttng_ust_trace_clock_get_freq_cb(lttng_ust_clock_freq_function *freq_cb);
  54
  55 /*
  56  * Set/Get clock override unique identifier.
  57  * LTTNG_UST_UUID_STR_LEN is the maximum length of uuid string. Includes
  58  * final \0.
  59  */
  60 #define LTTNG_UST_UUID_STR_LEN         37
  61
  62 int lttng_ust_trace_clock_set_uuid_cb(lttng_ust_clock_uuid_function uuid_cb);
  63 int lttng_ust_trace_clock_get_uuid_cb(lttng_ust_clock_uuid_function *uuid_cb);
  64
  65 /*
  66  * Set/Get clock override name.
  67  */
  68 int lttng_ust_trace_clock_set_name_cb(lttng_ust_clock_name_function name_cb);
  69 int lttng_ust_trace_clock_get_name_cb(lttng_ust_clock_name_function *name_cb);
  70
  71 /*
  72  * Set/Get clock override description.
  73  */
  74 int lttng_ust_trace_clock_set_description_cb(lttng_ust_clock_description_function description_cb);
  75 int lttng_ust_trace_clock_get_description_cb(lttng_ust_clock_description_function *description_cb);
  76
  77 /*
  78  * Use the clock override rather than the default clock.
  79  */
  80 int lttng_ust_enable_trace_clock_override(void);
  81
  82 #ifdef __cplusplus
  83 }
  84 #endif
  85
  86 #endif /* LTTNG_UST_CLOCK_H */