ceph/src/spdk/ocf/src/utils/utils_refcnt.c

   1 /*
   2  * Copyright(c) 2019 Intel Corporation
   3  * SPDX-License-Identifier: BSD-3-Clause-Clear
   4  */
   5
   6 #include "../utils/utils_refcnt.h"
   7
   8 void ocf_refcnt_init(struct ocf_refcnt *rc)
   9 {
  10         env_atomic_set(&rc->counter, 0);
  11         env_atomic_set(&rc->freeze, 0);
  12         env_atomic_set(&rc->callback, 0);
  13         rc->cb = NULL;
  14 }
  15
  16 void ocf_refcnt_dec(struct ocf_refcnt *rc)
  17 {
  18         int val = env_atomic_dec_return(&rc->counter);
  19         ENV_BUG_ON(val < 0);
  20
  21         if (!val && env_atomic_cmpxchg(&rc->callback, 1, 0))
  22                 rc->cb(rc->priv);
  23 }
  24
  25 bool ocf_refcnt_inc(struct ocf_refcnt  *rc)
  26 {
  27         if (!env_atomic_read(&rc->freeze)) {
  28                 env_atomic_inc(&rc->counter);
  29                 if (!env_atomic_read(&rc->freeze))
  30                         return  true;
  31                 else
  32                         ocf_refcnt_dec(rc);
  33         }
  34
  35         return false;
  36 }
  37
  38
  39 void ocf_refcnt_freeze(struct ocf_refcnt *rc)
  40 {
  41         env_atomic_inc(&rc->freeze);
  42 }
  43
  44 void ocf_refcnt_register_zero_cb(struct ocf_refcnt *rc, ocf_refcnt_cb_t cb,
  45                 void *priv)
  46 {
  47         ENV_BUG_ON(!env_atomic_read(&rc->freeze));
  48         ENV_BUG_ON(env_atomic_read(&rc->callback));
  49
  50         env_atomic_inc(&rc->counter);
  51         rc->cb = cb;
  52         rc->priv = priv;
  53         env_atomic_set(&rc->callback, 1);
  54         ocf_refcnt_dec(rc);
  55 }
  56
  57 void ocf_refcnt_unfreeze(struct ocf_refcnt *rc)
  58 {
  59         int val = env_atomic_dec_return(&rc->freeze);
  60         ENV_BUG_ON(val < 0);
  61 }