src/side.c

   1 // SPDX-License-Identifier: MIT
   2 /*
   3  * Copyright 2022 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  */
   5
   6 #include <side/trace.h>
   7 #include "tracer.h"
   8 #include "rcu.h"
   9 #include "smp.h"
  10
  11 #define SIDE_EVENT_ENABLED_KERNEL_USER_EVENT_MASK       0x80000000
  12
  13 struct side_rcu_gp_state rcu_gp = {
  14         .percpu_state = NULL,
  15         .nr_cpus = 0,
  16         .period = 0,
  17         .gp_lock = PTHREAD_MUTEX_INITIALIZER,
  18 };
  19
  20 /*
  21  * Lazy initialization for early use within library constructors.
  22  */
  23 static bool initialized;
  24
  25 static
  26 void side_init(void)
  27         __attribute__((constructor));
  28
  29 void side_call(const struct side_event_description *desc, const struct side_arg_vec_description *sav_desc)
  30 {
  31         if (side_unlikely(!initialized))
  32                 side_init();
  33         if (side_unlikely(desc->flags & SIDE_EVENT_FLAG_VARIADIC)) {
  34                 printf("ERROR: unexpected variadic event description\n");
  35                 abort();
  36         }
  37         if (side_unlikely(*desc->enabled & SIDE_EVENT_ENABLED_KERNEL_USER_EVENT_MASK)) {
  38                 // TODO: call kernel write.
  39         }
  40         //TODO: replace tracer_call by rcu iteration on list of registered callbacks
  41         tracer_call(desc, sav_desc, NULL);
  42 }
  43
  44 void side_call_variadic(const struct side_event_description *desc,
  45         const struct side_arg_vec_description *sav_desc,
  46         const struct side_arg_dynamic_event_struct *var_struct)
  47 {
  48         if (side_unlikely(!initialized))
  49                 side_init();
  50         if (side_unlikely(*desc->enabled & SIDE_EVENT_ENABLED_KERNEL_USER_EVENT_MASK)) {
  51                 // TODO: call kernel write.
  52         }
  53         //TODO: replace tracer_call by rcu iteration on list of registered callbacks
  54         tracer_call_variadic(desc, sav_desc, var_struct, NULL);
  55 }
  56
  57 void side_init(void)
  58 {
  59         if (initialized)
  60                 return;
  61         rcu_gp.nr_cpus = get_possible_cpus_array_len();
  62         if (!rcu_gp.nr_cpus)
  63                 abort();
  64         initialized = true;
  65 }