include/side/trace.h

   1 // SPDX-License-Identifier: MIT
   2 /*
   3  * Copyright 2022 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  */
   5
   6 #ifndef _SIDE_TRACE_H
   7 #define _SIDE_TRACE_H
   8
   9 #include <stdint.h>
  10 #include <inttypes.h>
  11 #include <stdlib.h>
  12 #include <stdio.h>
  13 #include <side/macros.h>
  14
  15 /* SIDE stands for "Static Instrumentation Dynamically Enabled" */
  16
  17 struct side_arg_vec;
  18 struct side_type_description;
  19 struct side_event_field;
  20
  21 enum side_type {
  22         SIDE_TYPE_U8,
  23         SIDE_TYPE_U16,
  24         SIDE_TYPE_U32,
  25         SIDE_TYPE_U64,
  26         SIDE_TYPE_S8,
  27         SIDE_TYPE_S16,
  28         SIDE_TYPE_S32,
  29         SIDE_TYPE_S64,
  30         SIDE_TYPE_STRING,
  31         SIDE_TYPE_DYNAMIC,
  32         SIDE_TYPE_STRUCT,
  33         SIDE_TYPE_ARRAY,
  34         SIDE_TYPE_VLA,
  35         SIDE_TYPE_VLA_VISITOR,
  36         //TODO:
  37         //specialized array and vla for fixed-size integers (optimization)
  38         //variants (discriminated unions)
  39 };
  40
  41 enum side_loglevel {
  42         SIDE_LOGLEVEL_EMERG = 0,
  43         SIDE_LOGLEVEL_ALERT = 1,
  44         SIDE_LOGLEVEL_CRIT = 2,
  45         SIDE_LOGLEVEL_ERR = 3,
  46         SIDE_LOGLEVEL_WARNING = 4,
  47         SIDE_LOGLEVEL_NOTICE = 5,
  48         SIDE_LOGLEVEL_INFO = 6,
  49         SIDE_LOGLEVEL_DEBUG = 7,
  50 };
  51
  52 enum side_visitor_status {
  53         SIDE_VISITOR_STATUS_ERROR = -1,
  54         SIDE_VISITOR_STATUS_OK = 0,
  55         SIDE_VISITOR_STATUS_END = 1,
  56 };
  57
  58 typedef enum side_visitor_status (*side_visitor_begin)(void *ctx);
  59 typedef enum side_visitor_status (*side_visitor_end)(void *ctx);
  60 typedef enum side_visitor_status (*side_visitor_get_next)(void *ctx, struct side_arg_vec *sav_elem);
  61
  62 struct side_type_description {
  63         enum side_type type;
  64         union {
  65                 struct {
  66                         uint32_t nr_fields;
  67                         const struct side_event_field *fields;
  68                 } side_struct;
  69                 struct {
  70                         uint32_t length;
  71                         const struct side_type_description *elem_type;
  72                 } side_array;
  73                 struct {
  74                         const struct side_type_description *elem_type;
  75                 } side_vla;
  76                 struct {
  77                         const struct side_type_description *elem_type;
  78                         side_visitor_begin begin;
  79                         side_visitor_end end;
  80                         side_visitor_get_next get_next;
  81                 } side_vla_visitor;
  82         } u;
  83 };
  84
  85 struct side_event_field {
  86         const char *field_name;
  87         struct side_type_description side_type;
  88 };
  89
  90 struct side_event_description {
  91         uint32_t version;
  92         uint32_t enabled;
  93         uint32_t loglevel;      /* enum side_loglevel */
  94         uint32_t nr_fields;
  95         const char *provider_name;
  96         const char *event_name;
  97         const struct side_event_field *fields;
  98 };
  99
 100 struct side_arg_vec {
 101         uint32_t type;  /* enum side_type */
 102         union {
 103                 uint8_t side_u8;
 104                 uint16_t side_u16;
 105                 uint32_t side_u32;
 106                 uint64_t side_u64;
 107                 int8_t side_s8;
 108                 int16_t side_s16;
 109                 int32_t side_s32;
 110                 int64_t side_s64;
 111                 const char *string;
 112                 const struct side_arg_vec_description *side_struct;
 113                 const struct side_arg_vec_description *side_array;
 114                 const struct side_arg_vec_description *side_vla;
 115                 void *side_vla_visitor_ctx;
 116         } u;
 117 };
 118
 119 struct side_arg_vec_description {
 120         const struct side_arg_vec *sav;
 121         uint32_t len;
 122 };
 123
 124 #define side_type_decl(_type)                   { .type = _type }
 125 #define side_field(_type, _name)                { .field_name = _name, .side_type = side_type_decl(_type) }
 126
 127 #define side_type_struct_decl(_fields) \
 128         { \
 129                 .type = SIDE_TYPE_STRUCT, \
 130                 .u = { \
 131                         .side_struct = { \
 132                                 .nr_fields = SIDE_ARRAY_SIZE(SIDE_PARAM(_fields)), \
 133                                 .fields = _fields, \
 134                         }, \
 135                 }, \
 136         }
 137 #define side_field_struct(_name, _fields) \
 138         { \
 139                 .field_name = _name, \
 140                 .side_type = side_type_struct_decl(SIDE_PARAM(_fields)), \
 141         }
 142
 143 #define side_type_array_decl(_elem_type, _length) \
 144         { \
 145                 .type = SIDE_TYPE_ARRAY, \
 146                 .u = { \
 147                         .side_array = { \
 148                                 .length = _length, \
 149                                 .elem_type = _elem_type, \
 150                         }, \
 151                 }, \
 152         }
 153 #define side_field_array(_name, _elem_type, _length) \
 154         { \
 155                 .field_name = _name, \
 156                 .side_type = side_type_array_decl(_elem_type, _length), \
 157         }
 158
 159 #define side_type_vla_decl(_elem_type) \
 160         { \
 161                 .type = SIDE_TYPE_VLA, \
 162                 .u = { \
 163                         .side_vla = { \
 164                                 .elem_type = _elem_type, \
 165                         }, \
 166                 }, \
 167         }
 168 #define side_field_vla(_name, _elem_type) \
 169         { \
 170                 .field_name = _name, \
 171                 .side_type = side_type_vla_decl(_elem_type), \
 172         }
 173
 174 #define side_type_vla_visitor_decl(_elem_type, _begin, _end, _get_next) \
 175         { \
 176                 .type = SIDE_TYPE_VLA_VISITOR, \
 177                 .u = { \
 178                         .side_vla_visitor = { \
 179                                 .elem_type = _elem_type, \
 180                                 .begin = _begin, \
 181                                 .end = _end, \
 182                                 .get_next = _get_next, \
 183                         }, \
 184                 }, \
 185         }
 186 #define side_field_vla_visitor(_name, _elem_type, _begin, _end, _get_next) \
 187         { \
 188                 .field_name = _name, \
 189                 .side_type = side_type_vla_visitor_decl(_elem_type, _begin, _end, _get_next), \
 190         }
 191
 192 #define side_vla_elem(...) \
 193         SIDE_COMPOUND_LITERAL(const struct side_type_description, side_type_decl(__VA_ARGS__))
 194
 195 #define side_vla_visitor_elem(...) \
 196         SIDE_COMPOUND_LITERAL(const struct side_type_description, side_type_decl(__VA_ARGS__))
 197
 198 #define side_array_elem(...) \
 199         SIDE_COMPOUND_LITERAL(const struct side_type_description, side_type_decl(__VA_ARGS__))
 200
 201 #define side_field_list(...) \
 202         SIDE_COMPOUND_LITERAL(const struct side_event_field, __VA_ARGS__)
 203
 204 #define side_arg_u8(val)        { .type = SIDE_TYPE_U8, .u = { .side_u8 = (val) } }
 205 #define side_arg_u16(val)       { .type = SIDE_TYPE_U16, .u = { .side_u16 = (val) } }
 206 #define side_arg_u32(val)       { .type = SIDE_TYPE_U32, .u = { .side_u32 = (val) } }
 207 #define side_arg_u64(val)       { .type = SIDE_TYPE_U64, .u = { .side_u64 = (val) } }
 208 #define side_arg_s8(val)        { .type = SIDE_TYPE_S8, .u = { .side_s8 = (val) } }
 209 #define side_arg_s16(val)       { .type = SIDE_TYPE_S16, .u = { .side_s16 = (val) } }
 210 #define side_arg_s32(val)       { .type = SIDE_TYPE_S32, .u = { .side_s32 = (val) } }
 211 #define side_arg_s64(val)       { .type = SIDE_TYPE_S64, .u = { .side_s64 = (val) } }
 212 #define side_arg_string(val)    { .type = SIDE_TYPE_STRING, .u = { .string = (val) } }
 213 #define side_arg_struct(_side_type)     { .type = SIDE_TYPE_STRUCT, .u = { .side_struct = (_side_type) } }
 214 #define side_arg_array(_side_type)      { .type = SIDE_TYPE_ARRAY, .u = { .side_array = (_side_type) } }
 215 #define side_arg_vla(_side_type)        { .type = SIDE_TYPE_VLA, .u = { .side_vla = (_side_type) } }
 216 #define side_arg_vla_visitor(_ctx)      { .type = SIDE_TYPE_VLA_VISITOR, .u = { .side_vla_visitor_ctx = (_ctx) } }
 217
 218 #define side_arg_define_vec(_identifier, _sav) \
 219         const struct side_arg_vec _identifier##_vec[] = { _sav }; \
 220         const struct side_arg_vec_description _identifier = { \
 221                 .sav = _identifier##_vec, \
 222                 .len = SIDE_ARRAY_SIZE(_identifier##_vec), \
 223         }
 224
 225 #define side_arg_list(...)      __VA_ARGS__
 226
 227 #define side_event_cond(desc) if (side_unlikely((desc)->enabled))
 228 #define side_event_call(desc, _sav) \
 229         { \
 230                 const struct side_arg_vec side_sav[] = { _sav }; \
 231                 const struct side_arg_vec_description sav_desc = { \
 232                         .sav = side_sav, \
 233                         .len = SIDE_ARRAY_SIZE(side_sav), \
 234                 }; \
 235                 tracer_call(desc, &sav_desc); \
 236         }
 237
 238 #define side_event(desc, sav) \
 239         side_event_cond(desc) \
 240                 side_event_call(desc, SIDE_PARAM(sav)); \
 241
 242 #define side_define_event(_identifier, _provider, _event, _loglevel, _fields) \
 243         struct side_event_description _identifier = { \
 244                 .version = 0, \
 245                 .enabled = 0, \
 246                 .loglevel = _loglevel, \
 247                 .nr_fields = SIDE_ARRAY_SIZE(SIDE_PARAM(_fields)), \
 248                 .provider_name = _provider, \
 249                 .event_name = _event, \
 250                 .fields = _fields, \
 251         }
 252
 253 #define side_declare_event(_identifier) \
 254         struct side_event_description _identifier
 255
 256 #endif /* _SIDE_TRACE_H */