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   ASSERT (first);                                               \
  85   if (first == p)                                               \
  86       first = (p)->next;                                        \
  87   else                                                          \
  88     {                                                           \
  89       __typeof__ (p) current = first;                           \
  90       while (current->next)                                     \
  91         {                                                       \
  92           if (current->next == p)                               \
  93             {                                                   \
  94               current->next = current->next->next;              \
  95               break;                                            \
  96             }                                                   \
  97           current = current->next;                              \
  98         }                                                       \
  99       ASSERT (current);                                         \
 100     }                                                           \
 101 }
 102
 103 #define _VLIB_INIT_FUNCTION_SYMBOL(x, type)     \
 104   _vlib_##type##_function_##x
 105
 106 #define VLIB_INIT_FUNCTION_SYMBOL(x)            \
 107   _VLIB_INIT_FUNCTION_SYMBOL(x, init)
 108 #define VLIB_MAIN_LOOP_ENTER_FUNCTION_SYMBOL(x)         \
 109   _VLIB_INIT_FUNCTION_SYMBOL(x, main_loop_enter)
 110 #define VLIB_MAIN_LOOP_EXIT_FUNCTION_SYMBOL(x)  \
 111   _VLIB_INIT_FUNCTION_SYMBOL(x, main_loop_exit)
 112 #define VLIB_CONFIG_FUNCTION_SYMBOL(x)          \
 113   _VLIB_INIT_FUNCTION_SYMBOL(x, config)
 114
 115 /* Declaration is global (e.g. not static) so that init functions can
 116    be called from other modules to resolve init function depend. */
 117
 118 #define VLIB_DECLARE_INIT_FUNCTION(x, tag)                      \
 119 vlib_init_function_t * _VLIB_INIT_FUNCTION_SYMBOL (x, tag) = x; \
 120 static void __vlib_add_##tag##_function_##x (void)              \
 121     __attribute__((__constructor__)) ;                          \
 122 static void __vlib_add_##tag##_function_##x (void)              \
 123 {                                                               \
 124  vlib_main_t * vm = vlib_get_main();                            \
 125  static _vlib_init_function_list_elt_t _vlib_init_function;     \
 126  _vlib_init_function.next_init_function                         \
 127     = vm->tag##_function_registrations;                         \
 128   vm->tag##_function_registrations = &_vlib_init_function;      \
 129  _vlib_init_function.f = &x;                                    \
 130 }                                                               \
 131 static void __vlib_rm_##tag##_function_##x (void)               \
 132     __attribute__((__destructor__)) ;                           \
 133 static void __vlib_rm_##tag##_function_##x (void)               \
 134 {                                                               \
 135   vlib_main_t * vm = vlib_get_main();                           \
 136   _vlib_init_function_list_elt_t *next;                         \
 137   if (vm->tag##_function_registrations->f == &x)                \
 138     {                                                           \
 139       vm->tag##_function_registrations =                        \
 140         vm->tag##_function_registrations->next_init_function;   \
 141       return;                                                   \
 142     }                                                           \
 143   next = vm->tag##_function_registrations;                      \
 144   while (next->next_init_function)                              \
 145     {                                                           \
 146       if (next->next_init_function->f == &x)                    \
 147         {                                                       \
 148           next->next_init_function =                            \
 149             next->next_init_function->next_init_function;       \
 150           return;                                               \
 151         }                                                       \
 152       next = next->next_init_function;                          \
 153     }                                                           \
 154 }
 155
 156 #define VLIB_INIT_FUNCTION(x) VLIB_DECLARE_INIT_FUNCTION(x,init)
 157 #define VLIB_WORKER_INIT_FUNCTION(x) VLIB_DECLARE_INIT_FUNCTION(x,worker_init)
 158
 159 #define VLIB_MAIN_LOOP_ENTER_FUNCTION(x) \
 160   VLIB_DECLARE_INIT_FUNCTION(x,main_loop_enter)
 161 #define VLIB_MAIN_LOOP_EXIT_FUNCTION(x) \
 162 VLIB_DECLARE_INIT_FUNCTION(x,main_loop_exit)
 163
 164 #define VLIB_CONFIG_FUNCTION(x,n,...)                           \
 165     __VA_ARGS__ vlib_config_function_runtime_t                  \
 166     VLIB_CONFIG_FUNCTION_SYMBOL(x);                             \
 167 static void __vlib_add_config_function_##x (void)               \
 168     __attribute__((__constructor__)) ;                          \
 169 static void __vlib_add_config_function_##x (void)               \
 170 {                                                               \
 171     vlib_main_t * vm = vlib_get_main();                         \
 172     VLIB_CONFIG_FUNCTION_SYMBOL(x).next_registration            \
 173        = vm->config_function_registrations;                     \
 174     vm->config_function_registrations                           \
 175        = &VLIB_CONFIG_FUNCTION_SYMBOL(x);                       \
 176 }                                                               \
 177 static void __vlib_rm_config_function_##x (void)                \
 178     __attribute__((__destructor__)) ;                           \
 179 static void __vlib_rm_config_function_##x (void)                \
 180 {                                                               \
 181     vlib_main_t * vm = vlib_get_main();                         \
 182     vlib_config_function_runtime_t *p =                         \
 183        & VLIB_CONFIG_FUNCTION_SYMBOL (x);                       \
 184     VLIB_REMOVE_FROM_LINKED_LIST                                \
 185       (vm->config_function_registrations, p, next_registration);\
 186 }                                                               \
 187   vlib_config_function_runtime_t                                \
 188     VLIB_CONFIG_FUNCTION_SYMBOL (x)                             \
 189   = {                                                           \
 190     .name = n,                                                  \
 191     .function = x,                                              \
 192     .is_early = 0,                                              \
 193   }
 194
 195 #define VLIB_EARLY_CONFIG_FUNCTION(x,n,...)                     \
 196     __VA_ARGS__ vlib_config_function_runtime_t                  \
 197     VLIB_CONFIG_FUNCTION_SYMBOL(x);                             \
 198 static void __vlib_add_config_function_##x (void)               \
 199     __attribute__((__constructor__)) ;                          \
 200 static void __vlib_add_config_function_##x (void)               \
 201 {                                                               \
 202     vlib_main_t * vm = vlib_get_main();                         \
 203     VLIB_CONFIG_FUNCTION_SYMBOL(x).next_registration            \
 204        = vm->config_function_registrations;                     \
 205     vm->config_function_registrations                           \
 206        = &VLIB_CONFIG_FUNCTION_SYMBOL(x);                       \
 207 }                                                               \
 208 static void __vlib_rm_config_function_##x (void)                \
 209     __attribute__((__destructor__)) ;                           \
 210 static void __vlib_rm_config_function_##x (void)                \
 211 {                                                               \
 212     vlib_main_t * vm = vlib_get_main();                         \
 213     vlib_config_function_runtime_t *p =                         \
 214        & VLIB_CONFIG_FUNCTION_SYMBOL (x);                       \
 215     VLIB_REMOVE_FROM_LINKED_LIST                                \
 216       (vm->config_function_registrations, p, next_registration);\
 217 }                                                               \
 218   vlib_config_function_runtime_t                                \
 219     VLIB_CONFIG_FUNCTION_SYMBOL (x)                             \
 220   = {                                                           \
 221     .name = n,                                                  \
 222     .function = x,                                              \
 223     .is_early = 1,                                              \
 224   }
 225
 226 /* Call given init function: used for init function dependencies. */
 227 #define vlib_call_init_function(vm, x)                                  \
 228   ({                                                                    \
 229     extern vlib_init_function_t * VLIB_INIT_FUNCTION_SYMBOL (x);        \
 230     vlib_init_function_t * _f = VLIB_INIT_FUNCTION_SYMBOL (x);          \
 231     clib_error_t * _error = 0;                                          \
 232     if (! hash_get (vm->init_functions_called, _f))                     \
 233       {                                                                 \
 234         hash_set1 (vm->init_functions_called, _f);                      \
 235         _error = _f (vm);                                               \
 236       }                                                                 \
 237     _error;                                                             \
 238   })
 239
 240 /* Don't call given init function: used to suppress parts of the netstack */
 241 #define vlib_mark_init_function_complete(vm, x)                         \
 242   ({                                                                    \
 243     extern vlib_init_function_t * VLIB_INIT_FUNCTION_SYMBOL (x);        \
 244     vlib_init_function_t * _f = VLIB_INIT_FUNCTION_SYMBOL (x);          \
 245     hash_set1 (vm->init_functions_called, _f);                          \
 246   })
 247
 248 #define vlib_call_post_graph_init_function(vm, x)                       \
 249   ({                                                                    \
 250     extern vlib_init_function_t * VLIB_POST_GRAPH_INIT_FUNCTION_SYMBOL (x); \
 251     vlib_init_function_t * _f = VLIB_POST_GRAPH_INIT_FUNCTION_SYMBOL (x); \
 252     clib_error_t * _error = 0;                                          \
 253     if (! hash_get (vm->init_functions_called, _f))                     \
 254       {                                                                 \
 255         hash_set1 (vm->init_functions_called, _f);                      \
 256         _error = _f (vm);                                               \
 257       }                                                                 \
 258     _error;                                                             \
 259   })
 260
 261 #define vlib_call_config_function(vm, x)                        \
 262   ({                                                            \
 263     vlib_config_function_runtime_t * _r;                        \
 264     clib_error_t * _error = 0;                                  \
 265     extern vlib_config_function_runtime_t                       \
 266       VLIB_CONFIG_FUNCTION_SYMBOL (x);                          \
 267                                                                 \
 268     _r = &VLIB_CONFIG_FUNCTION_SYMBOL (x);                      \
 269     if (! hash_get (vm->init_functions_called, _r->function))   \
 270       {                                                         \
 271         hash_set1 (vm->init_functions_called, _r->function);    \
 272         _error = _r->function (vm, &_r->input);                 \
 273       }                                                         \
 274     _error;                                                     \
 275   })
 276
 277 /* External functions. */
 278 clib_error_t *vlib_call_all_init_functions (struct vlib_main_t *vm);
 279 clib_error_t *vlib_call_all_config_functions (struct vlib_main_t *vm,
 280                                               unformat_input_t * input,
 281                                               int is_early);
 282 clib_error_t *vlib_call_all_main_loop_enter_functions (struct vlib_main_t
 283                                                        *vm);
 284 clib_error_t *vlib_call_all_main_loop_exit_functions (struct vlib_main_t *vm);
 285 clib_error_t *vlib_call_init_exit_functions (struct vlib_main_t *vm,
 286                                              _vlib_init_function_list_elt_t *
 287                                              head, int call_once);
 288
 289 #define foreach_vlib_module_reference           \
 290   _ (node_cli)                                  \
 291   _ (trace_cli)
 292
 293 /* Dummy function to get node_cli.c linked in. */
 294 #define _(x) void vlib_##x##_reference (void);
 295 foreach_vlib_module_reference
 296 #undef _
 297 #endif /* included_vlib_init_h */
 298 /*
 299  * fd.io coding-style-patch-verification: ON
 300  *
 301  * Local Variables:
 302  * eval: (c-set-style "gnu")
 303  * End:
 304  */