src/vlib/init.h

   1 /*
   2  * Copyright (c) 2015 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15 /*
  16  * init.h: mechanism for functions to be called at init/exit.
  17  *
  18  * Copyright (c) 2008 Eliot Dresselhaus
  19  *
  20  * Permission is hereby granted, free of charge, to any person obtaining
  21  * a copy of this software and associated documentation files (the
  22  * "Software"), to deal in the Software without restriction, including
  23  * without limitation the rights to use, copy, modify, merge, publish,
  24  * distribute, sublicense, and/or sell copies of the Software, and to
  25  * permit persons to whom the Software is furnished to do so, subject to
  26  * the following conditions:
  27  *
  28  * The above copyright notice and this permission notice shall be
  29  * included in all copies or substantial portions of the Software.
  30  *
  31  *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  32  *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  33  *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  34  *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  35  *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  36  *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  37  *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  38  */
  39
  40 #ifndef included_vlib_init_h
  41 #define included_vlib_init_h
  42
  43 #include <vppinfra/error.h>
  44 #include <vppinfra/format.h>
  45 #include <vppinfra/hash.h>
  46
  47 /* Init/exit functions: called at start/end of main routine.  Init
  48    functions are typically used to register and setup packet
  49    processing nodes.  */
  50
  51 typedef clib_error_t *(vlib_init_function_t) (struct vlib_main_t * vm);
  52
  53 typedef struct _vlib_init_function_list_elt
  54 {
  55   struct _vlib_init_function_list_elt *next_init_function;
  56   vlib_init_function_t *f;
  57 } _vlib_init_function_list_elt_t;
  58
  59 /* Configuration functions: called with configuration input just before
  60    main polling loop starts. */
  61 typedef clib_error_t *(vlib_config_function_t) (struct vlib_main_t * vm,
  62                                                 unformat_input_t * input);
  63
  64 typedef struct vlib_config_function_runtime_t
  65 {
  66   /* Function to call.  Set to null once function has already been called. */
  67   vlib_config_function_t *function;
  68
  69   /* Input for function. */
  70   unformat_input_t input;
  71
  72   /* next config function registration */
  73   struct vlib_config_function_runtime_t *next_registration;
  74
  75   /* To be invoked as soon as the clib heap is available */
  76   u8 is_early;
  77
  78   /* Name used to distinguish input on command line. */
  79   char name[32];
  80 } vlib_config_function_runtime_t;
  81
  82 #define VLIB_REMOVE_FROM_LINKED_LIST(first,p,next)              \
  83 {                                                               \
  84   if (first == p)                                               \
  85       first = (p)->next;                                        \
  86   else                                                          \
  87     {                                                           \
  88       __typeof__ (p) current = first;                           \
  89         while (current->next)                                   \
  90           {                                                     \
  91             if (current->next == p)                             \
  92               {                                                 \
  93                 current->next = current->next->next;            \
  94                 break;                                          \
  95               }                                                 \
  96             current = current->next;                            \
  97           }                                                     \
  98     }                                                           \
  99 }
 100
 101 #define _VLIB_INIT_FUNCTION_SYMBOL(x, type)     \
 102   _vlib_##type##_function_##x
 103
 104 #define VLIB_INIT_FUNCTION_SYMBOL(x)            \
 105   _VLIB_INIT_FUNCTION_SYMBOL(x, init)
 106 #define VLIB_MAIN_LOOP_ENTER_FUNCTION_SYMBOL(x)         \
 107   _VLIB_INIT_FUNCTION_SYMBOL(x, main_loop_enter)
 108 #define VLIB_MAIN_LOOP_EXIT_FUNCTION_SYMBOL(x)  \
 109   _VLIB_INIT_FUNCTION_SYMBOL(x, main_loop_exit)
 110 #define VLIB_CONFIG_FUNCTION_SYMBOL(x)          \
 111   _VLIB_INIT_FUNCTION_SYMBOL(x, config)
 112
 113 /* Declaration is global (e.g. not static) so that init functions can
 114    be called from other modules to resolve init function depend. */
 115
 116 #define VLIB_DECLARE_INIT_FUNCTION(x, tag)                      \
 117 vlib_init_function_t * _VLIB_INIT_FUNCTION_SYMBOL (x, tag) = x; \
 118 static void __vlib_add_##tag##_function_##x (void)              \
 119     __attribute__((__constructor__)) ;                          \
 120 static void __vlib_add_##tag##_function_##x (void)              \
 121 {                                                               \
 122  vlib_main_t * vm = vlib_get_main();                            \
 123  static _vlib_init_function_list_elt_t _vlib_init_function;     \
 124  _vlib_init_function.next_init_function                         \
 125     = vm->tag##_function_registrations;                         \
 126   vm->tag##_function_registrations = &_vlib_init_function;      \
 127  _vlib_init_function.f = &x;                                    \
 128 }                                                               \
 129 static void __vlib_rm_##tag##_function_##x (void)               \
 130     __attribute__((__destructor__)) ;                           \
 131 static void __vlib_rm_##tag##_function_##x (void)               \
 132 {                                                               \
 133   vlib_main_t * vm = vlib_get_main();                           \
 134   _vlib_init_function_list_elt_t *next;                         \
 135   if (vm->tag##_function_registrations->f == &x)                \
 136     {                                                           \
 137       vm->tag##_function_registrations =                        \
 138         vm->tag##_function_registrations->next_init_function;   \
 139       return;                                                   \
 140     }                                                           \
 141   next = vm->tag##_function_registrations;                      \
 142   while (next->next_init_function)                              \
 143     {                                                           \
 144       if (next->next_init_function->f == &x)                    \
 145         {                                                       \
 146           next->next_init_function =                            \
 147             next->next_init_function->next_init_function;       \
 148           return;                                               \
 149         }                                                       \
 150       next = next->next_init_function;                          \
 151     }                                                           \
 152 }
 153
 154 #define VLIB_INIT_FUNCTION(x) VLIB_DECLARE_INIT_FUNCTION(x,init)
 155 #define VLIB_WORKER_INIT_FUNCTION(x) VLIB_DECLARE_INIT_FUNCTION(x,worker_init)
 156
 157 #define VLIB_MAIN_LOOP_ENTER_FUNCTION(x) \
 158   VLIB_DECLARE_INIT_FUNCTION(x,main_loop_enter)
 159 #define VLIB_MAIN_LOOP_EXIT_FUNCTION(x) \
 160 VLIB_DECLARE_INIT_FUNCTION(x,main_loop_exit)
 161
 162 #define VLIB_CONFIG_FUNCTION(x,n,...)                           \
 163     __VA_ARGS__ vlib_config_function_runtime_t                  \
 164     VLIB_CONFIG_FUNCTION_SYMBOL(x);                             \
 165 static void __vlib_add_config_function_##x (void)               \
 166     __attribute__((__constructor__)) ;                          \
 167 static void __vlib_add_config_function_##x (void)               \
 168 {                                                               \
 169     vlib_main_t * vm = vlib_get_main();                         \
 170     VLIB_CONFIG_FUNCTION_SYMBOL(x).next_registration            \
 171        = vm->config_function_registrations;                     \
 172     vm->config_function_registrations                           \
 173        = &VLIB_CONFIG_FUNCTION_SYMBOL(x);                       \
 174 }                                                               \
 175 static void __vlib_rm_config_function_##x (void)                \
 176     __attribute__((__destructor__)) ;                           \
 177 static void __vlib_rm_config_function_##x (void)                \
 178 {                                                               \
 179     vlib_main_t * vm = vlib_get_main();                         \
 180     vlib_config_function_runtime_t *p =                         \
 181        & VLIB_CONFIG_FUNCTION_SYMBOL (x);                       \
 182     VLIB_REMOVE_FROM_LINKED_LIST                                \
 183       (vm->config_function_registrations, p, next_registration);\
 184 }                                                               \
 185   vlib_config_function_runtime_t                                \
 186     VLIB_CONFIG_FUNCTION_SYMBOL (x)                             \
 187   = {                                                           \
 188     .name = n,                                                  \
 189     .function = x,                                              \
 190     .is_early = 0,                                              \
 191   }
 192
 193 #define VLIB_EARLY_CONFIG_FUNCTION(x,n,...)                     \
 194     __VA_ARGS__ vlib_config_function_runtime_t                  \
 195     VLIB_CONFIG_FUNCTION_SYMBOL(x);                             \
 196 static void __vlib_add_config_function_##x (void)               \
 197     __attribute__((__constructor__)) ;                          \
 198 static void __vlib_add_config_function_##x (void)               \
 199 {                                                               \
 200     vlib_main_t * vm = vlib_get_main();                         \
 201     VLIB_CONFIG_FUNCTION_SYMBOL(x).next_registration            \
 202        = vm->config_function_registrations;                     \
 203     vm->config_function_registrations                           \
 204        = &VLIB_CONFIG_FUNCTION_SYMBOL(x);                       \
 205 }                                                               \
 206 static void __vlib_rm_config_function_##x (void)                \
 207     __attribute__((__destructor__)) ;                           \
 208 static void __vlib_rm_config_function_##x (void)                \
 209 {                                                               \
 210     vlib_main_t * vm = vlib_get_main();                         \
 211     vlib_config_function_runtime_t *p =                         \
 212        & VLIB_CONFIG_FUNCTION_SYMBOL (x);                       \
 213     VLIB_REMOVE_FROM_LINKED_LIST                                \
 214       (vm->config_function_registrations, p, next_registration);\
 215 }                                                               \
 216   vlib_config_function_runtime_t                                \
 217     VLIB_CONFIG_FUNCTION_SYMBOL (x)                             \
 218   = {                                                           \
 219     .name = n,                                                  \
 220     .function = x,                                              \
 221     .is_early = 1,                                              \
 222   }
 223
 224 /* Call given init function: used for init function dependencies. */
 225 #define vlib_call_init_function(vm, x)                                  \
 226   ({                                                                    \
 227     extern vlib_init_function_t * VLIB_INIT_FUNCTION_SYMBOL (x);        \
 228     vlib_init_function_t * _f = VLIB_INIT_FUNCTION_SYMBOL (x);          \
 229     clib_error_t * _error = 0;                                          \
 230     if (! hash_get (vm->init_functions_called, _f))                     \
 231       {                                                                 \
 232         hash_set1 (vm->init_functions_called, _f);                      \
 233         _error = _f (vm);                                               \
 234       }                                                                 \
 235     _error;                                                             \
 236   })
 237
 238 /* Don't call given init function: used to suppress parts of the netstack */
 239 #define vlib_mark_init_function_complete(vm, x)                         \
 240   ({                                                                    \
 241     extern vlib_init_function_t * VLIB_INIT_FUNCTION_SYMBOL (x);        \
 242     vlib_init_function_t * _f = VLIB_INIT_FUNCTION_SYMBOL (x);          \
 243     hash_set1 (vm->init_functions_called, _f);                          \
 244   })
 245
 246 #define vlib_call_post_graph_init_function(vm, x)                       \
 247   ({                                                                    \
 248     extern vlib_init_function_t * VLIB_POST_GRAPH_INIT_FUNCTION_SYMBOL (x); \
 249     vlib_init_function_t * _f = VLIB_POST_GRAPH_INIT_FUNCTION_SYMBOL (x); \
 250     clib_error_t * _error = 0;                                          \
 251     if (! hash_get (vm->init_functions_called, _f))                     \
 252       {                                                                 \
 253         hash_set1 (vm->init_functions_called, _f);                      \
 254         _error = _f (vm);                                               \
 255       }                                                                 \
 256     _error;                                                             \
 257   })
 258
 259 #define vlib_call_config_function(vm, x)                        \
 260   ({                                                            \
 261     vlib_config_function_runtime_t * _r;                        \
 262     clib_error_t * _error = 0;                                  \
 263     extern vlib_config_function_runtime_t                       \
 264       VLIB_CONFIG_FUNCTION_SYMBOL (x);                          \
 265                                                                 \
 266     _r = &VLIB_CONFIG_FUNCTION_SYMBOL (x);                      \
 267     if (! hash_get (vm->init_functions_called, _r->function))   \
 268       {                                                         \
 269         hash_set1 (vm->init_functions_called, _r->function);    \
 270         _error = _r->function (vm, &_r->input);                 \
 271       }                                                         \
 272     _error;                                                     \
 273   })
 274
 275 /* External functions. */
 276 clib_error_t *vlib_call_all_init_functions (struct vlib_main_t *vm);
 277 clib_error_t *vlib_call_all_config_functions (struct vlib_main_t *vm,
 278                                               unformat_input_t * input,
 279                                               int is_early);
 280 clib_error_t *vlib_call_all_main_loop_enter_functions (struct vlib_main_t
 281                                                        *vm);
 282 clib_error_t *vlib_call_all_main_loop_exit_functions (struct vlib_main_t *vm);
 283 clib_error_t *vlib_call_init_exit_functions (struct vlib_main_t *vm,
 284                                              _vlib_init_function_list_elt_t *
 285                                              head, int call_once);
 286
 287 #define foreach_vlib_module_reference           \
 288   _ (node_cli)                                  \
 289   _ (trace_cli)
 290
 291 /* Dummy function to get node_cli.c linked in. */
 292 #define _(x) void vlib_##x##_reference (void);
 293 foreach_vlib_module_reference
 294 #undef _
 295 #endif /* included_vlib_init_h */
 296 /*
 297  * fd.io coding-style-patch-verification: ON
 298  *
 299  * Local Variables:
 300  * eval: (c-set-style "gnu")
 301  * End:
 302  */