/* * Copyright (c) 2020 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /** @file * @brief Callback multiplex scheme */ #ifndef included_callback_data_h #define included_callback_data_h #include /** @brief Declare and define a callback set type * @param set_t_ The set type to define * @param cb_t_ The callback type to use */ #define clib_callback_data_typedef(set_t_, cb_t_) \ typedef struct set_t_ \ { \ cb_t_* curr; \ cb_t_* volatile next; \ cb_t_* spare; \ clib_spinlock_t* lock; \ } set_t_ /** @brief Initialize a callback set * @param set_ The callback set to initialize * @param lock_ The lock to use, if any */ #define clib_callback_data_init(set_,lock_) \ do { \ (set_)->lock = (lock_); \ (set_)->curr = 0; \ (set_)->next = 0; \ (set_)->spare = 0; \ } while (0) /** @brief Add a callback to the specified callback set * @param set_ The callback set * @param value_ The value_ to assign the callback * * Add a callback from the indicated callback set. If the set is * currently being iterated, then the change will be applied after the * current full iteration, and prior to the next full iteration. */ #define clib_callback_data_add(set_,value_) \ do { \ clib_spinlock_lock_if_init ((set_)->lock); \ typeof ((set_)->next) next_ = (set_)->next; \ if (PREDICT_TRUE (next_ == 0)) \ { \ next_ = (set_)->spare; \ (set_)->spare = 0; \ vec_append (next_, (set_)->curr); \ } \ u32 sz_ = vec_len (next_); \ vec_validate (next_, sz_); \ next_[sz_] = (value_); \ (set_)->next = next_; \ clib_spinlock_unlock_if_init ((set_)->lock); \ } while (0) /** @brief Remove a callback from the specified callback set * @param set_ The callback set * @param fp_ The current callback function * @return 1 if the function was removed, 0 if not * * Remove a callback from the indicated callback set. Idempotent. If * the set is currently being iterated, then the change will be applied * after the current full iteration, and prior to the next full * iteration. */ #define clib_callback_data_remove(set_,fp_) \ ({ \ int found_ = 0; \ clib_spinlock_lock_if_init ((set_)->lock); \ typeof ((set_)->next) next_ = (set_)->next; \ if (PREDICT_TRUE (next_ == 0)) \ { \ next_ = (set_)->spare; \ (set_)->spare = 0; \ vec_append (next_, (set_)->curr); \ } \ u32 sz_ = vec_len (next_); \ u32 i_; \ for (i_ = 0; i_ < sz_; i_++) \ if (next_[i_].fp == (fp_)) \ { \ vec_delete (next_, 1, i_); \ found_ = 1; \ break; \ } \ (set_)->next = next_; \ clib_spinlock_unlock_if_init ((set_)->lock); \ found_; \ }) /** @brief Swap a callback in the specified callback set * @param set_ The callback set * @param fp_ The current callback function * @param value_ The value_ to assign the callback * @return 1 if the function was swapped, 0 if not * * Swap a callback in the indicated callback set. If the callback is * not found, then nothing is done. If the set is currently being * iterated, then the change will be applied after the current full * iteration, and prior to the next full iteration. */ #define clib_callback_data_swap(set_,fp_,value_) \ ({ \ int found_ = 0; \ clib_spinlock_lock_if_init ((set_)->lock); \ typeof ((set_)->next) next_ = (set_)->next; \ if (PREDICT_TRUE (next_ == 0)) \ { \ next_ = (set_)->spare; \ (set_)->spare = 0; \ vec_append (next_, (set_)->curr); \ } \ u32 sz_ = vec_len (next_); \ u32 i_; \ for (i_ = 0; i_ < sz_; i_++) \ if (next_[i_].fp == (fp_)) \ { \ next_[i_] = (value_); \ found_ = 1; \ break; \ } \ (set_)->next = next_; \ clib_spinlock_unlock_if_init ((set_)->lock); \ found_; \ }) /** @brief Ensure a callback is in the specified callback set * @param set_ The callback set * @param value_ The value_ to assign the callback * @return 1 if the function was swapped, 0 if not * * Add or swap a callback in the indicated callback set. If the * callback is already in the set, it is replaced. If the callback is * not found, then it is added. If the set is currently being * iterated, then the change will be applied after the current full * iteration, and prior to the next full iteration. */ #define clib_callback_data_ensure(set_,value_) \ do { \ int found_ = 0; \ clib_spinlock_lock_if_init ((set_)->lock); \ typeof ((set_)->next) next_ = (set_)->next; \ if (PREDICT_TRUE (next_ == 0)) \ { \ next_ = (set_)->spare; \ (set_)->spare = 0; \ vec_append (next_, (set_)->curr); \ } \ u32 sz_ = vec_len (next_); \ u32 i_; \ for (i_ = 0; i_ < sz_; i_++) \ if (next_[i_].fp == (value_).fp) \ { \ found_ = 1; \ break; \ } \ if (!found_) \ vec_validate (next_, i_); \ next_[i_] = (value_); \ (set_)->next = next_; \ clib_spinlock_unlock_if_init ((set_)->lock); \ } while(0) /** @brief Enable/Disable the specified callback * @param set_ The callback set * @param fp_ The callback function * @param ena_ 1 to enable, 0 to disable * * Enable or disable a callback function, with no data. */ #define clib_callback_data_enable_disable(set_,fp_,ena_) \ do { \ if (ena_) \ { \ typeof ((set_)->next[0]) data_ = { .fp = (fp_) }; \ clib_callback_data_add ((set_), data_); \ } \ else \ clib_callback_data_remove ((set_), (fp_)); \ } while (0) /** @brief Get the value of a callback, if set. * @param set_ The callback set * @param fp_ The callback function * @param v_ Set to the callback's current value * @return 1 if the function is in the set, 0 if not */ #define clib_callback_data_get_value(set_,fp_,v_) \ ({ \ int found_ = 0; \ clib_spinlock_lock_if_init ((set_)->lock); \ typeof ((set_)->next) search_ = (set_)->next; \ if (PREDICT_TRUE (search_ == 0)) \ search_ = (set_)->curr; \ u32 sz_ = vec_len (search_); \ u32 i_; \ for (i_ = 0; i_ < sz_; i_++) \ if (search_[i_].fp == (fp_)) \ { \ (v_) = search_[i]; \ found_ = 1; \ break; \ } \ clib_spinlock_unlock_if_init ((set_)->lock); \ found_; \ }) /** @brief Check if callback is set * @param set_ The callback set * @param fp_ The callback function * @return 1 if the function is in the set, 0 if not */ #define clib_callback_data_is_set(set_,fp_) \ ({ \ int found_ = 0; \ clib_spinlock_lock_if_init ((set_)->lock); \ typeof ((set_)->next) search_ = (set_)->next; \ if (PREDICT_TRUE (search_ == 0)) \ search_ = (set_)->curr; \ u32 sz_ = vec_len (search_); \ u32 i_; \ for (i_ = 0; i_ < sz_; i_