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Diffstat (limited to 'src/libnetdata/dictionary/dictionary-internals.h')
| -rw-r--r-- | src/libnetdata/dictionary/dictionary-internals.h | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/src/libnetdata/dictionary/dictionary-internals.h b/src/libnetdata/dictionary/dictionary-internals.h new file mode 100644 index 000000000..54e59564f --- /dev/null +++ b/src/libnetdata/dictionary/dictionary-internals.h @@ -0,0 +1,259 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#ifndef NETDATA_DICTIONARY_INTERNALS_H +#define NETDATA_DICTIONARY_INTERNALS_H + +#define DICTIONARY_INTERNALS +#include "../libnetdata.h" + +// runtime flags of the dictionary - must be checked with atomics +typedef enum __attribute__ ((__packed__)) { + DICT_FLAG_NONE = 0, + DICT_FLAG_DESTROYED = (1 << 0), // this dictionary has been destroyed +} DICT_FLAGS; + +#define dict_flag_check(dict, flag) (__atomic_load_n(&((dict)->flags), __ATOMIC_RELAXED) & (flag)) +#define dict_flag_set(dict, flag) __atomic_or_fetch(&((dict)->flags), flag, __ATOMIC_RELAXED) +#define dict_flag_clear(dict, flag) __atomic_and_fetch(&((dict)->flags), ~(flag), __ATOMIC_RELAXED) + +// flags macros +#define is_dictionary_destroyed(dict) dict_flag_check(dict, DICT_FLAG_DESTROYED) + +// configuration options macros +#define is_dictionary_single_threaded(dict) ((dict)->options & DICT_OPTION_SINGLE_THREADED) +#define is_view_dictionary(dict) ((dict)->master) +#define is_master_dictionary(dict) (!is_view_dictionary(dict)) + +typedef enum __attribute__ ((__packed__)) item_options { + ITEM_OPTION_NONE = 0, + ITEM_OPTION_ALLOCATED_NAME = (1 << 0), // the name pointer is a STRING + + // IMPORTANT: This is 1-bit - to add more change ITEM_OPTIONS_BITS +} ITEM_OPTIONS; + +typedef enum __attribute__ ((__packed__)) item_flags { + ITEM_FLAG_NONE = 0, + ITEM_FLAG_DELETED = (1 << 0), // this item is marked deleted, so it is not available for traversal (deleted from the index too) + ITEM_FLAG_BEING_CREATED = (1 << 1), // this item is currently being created - this flag is removed when construction finishes + + // IMPORTANT: This is 8-bit +} ITEM_FLAGS; + +#define item_flag_check(item, flag) (__atomic_load_n(&((item)->flags), __ATOMIC_RELAXED) & (flag)) +#define item_flag_set(item, flag) __atomic_or_fetch(&((item)->flags), flag, __ATOMIC_RELAXED) +#define item_flag_clear(item, flag) __atomic_and_fetch(&((item)->flags), ~(flag), __ATOMIC_RELAXED) + +#define item_shared_flag_check(item, flag) (__atomic_load_n(&((item)->shared->flags), __ATOMIC_RELAXED) & (flag)) +#define item_shared_flag_set(item, flag) __atomic_or_fetch(&((item)->shared->flags), flag, __ATOMIC_RELAXED) +#define item_shared_flag_clear(item, flag) __atomic_and_fetch(&((item)->shared->flags), ~(flag), __ATOMIC_RELAXED) + +#define REFCOUNT_DELETING (-100) + +#define ITEM_FLAGS_TYPE uint8_t +#define KEY_LEN_TYPE uint32_t +#define VALUE_LEN_TYPE uint32_t + +#define ITEM_OPTIONS_BITS 1 +#define KEY_LEN_BITS ((sizeof(KEY_LEN_TYPE) * 8) - (sizeof(ITEM_FLAGS_TYPE) * 8) - ITEM_OPTIONS_BITS) +#define KEY_LEN_MAX ((1 << KEY_LEN_BITS) - 1) + +#define VALUE_LEN_BITS ((sizeof(VALUE_LEN_TYPE) * 8) - (sizeof(ITEM_FLAGS_TYPE) * 8)) +#define VALUE_LEN_MAX ((1 << VALUE_LEN_BITS) - 1) + + +/* + * Every item in the dictionary has the following structure. + */ + +typedef int32_t REFCOUNT; + +typedef struct dictionary_item_shared { + void *value; // the value of the dictionary item + + // the order of the following items is important! + // The total of their storage should be 64-bits + + REFCOUNT links; // how many links this item has + VALUE_LEN_TYPE value_len:VALUE_LEN_BITS; // the size of the value + ITEM_FLAGS_TYPE flags; // shared flags +} DICTIONARY_ITEM_SHARED; + +struct dictionary_item { +#ifdef NETDATA_INTERNAL_CHECKS + DICTIONARY *dict; + pid_t creator_pid; + pid_t deleter_pid; + pid_t ll_adder_pid; + pid_t ll_remover_pid; +#endif + + DICTIONARY_ITEM_SHARED *shared; + + struct dictionary_item *next; // a double linked list to allow fast insertions and deletions + struct dictionary_item *prev; + + union { + STRING *string_name; // the name of the dictionary item + char *caller_name; // the user supplied string pointer + // void *key_ptr; // binary key pointer + }; + + // the order of the following items is important! + // The total of their storage should be 64-bits + + REFCOUNT refcount; // the private reference counter + + KEY_LEN_TYPE key_len:KEY_LEN_BITS; // the size of key indexed (for strings, including the null terminator) + // this is (2^23 - 1) = 8.388.607 bytes max key length. + + ITEM_OPTIONS options:ITEM_OPTIONS_BITS; // permanent configuration options + // (no atomic operations on this - they never change) + + ITEM_FLAGS_TYPE flags; // runtime changing flags for this item (atomic operations on this) + // cannot be a bit field because of atomics. +}; + +struct dictionary_hooks { + REFCOUNT links; + usec_t last_master_deletion_us; + + dict_cb_insert_t insert_callback; + void *insert_callback_data; + + dict_cb_conflict_t conflict_callback; + void *conflict_callback_data; + + dict_cb_react_t react_callback; + void *react_callback_data; + + dict_cb_delete_t delete_callback; + void *delelte_callback_data; +}; + +struct dictionary { +#ifdef NETDATA_INTERNAL_CHECKS + const char *creation_function; + const char *creation_file; + size_t creation_line; + pid_t creation_tid; +#endif + + usec_t last_gc_run_us; + DICT_OPTIONS options; // the configuration flags of the dictionary (they never change - no atomics) + DICT_FLAGS flags; // run time flags for the dictionary (they change all the time - atomics needed) + + ARAL *value_aral; + + struct { // support for multiple indexing engines + Pvoid_t JudyHSArray; // the hash table + RW_SPINLOCK rw_spinlock; // protect the index + } index; + + struct { + DICTIONARY_ITEM *list; // the double linked list of all items in the dictionary + RW_SPINLOCK rw_spinlock; // protect the linked-list + pid_t writer_pid; // the gettid() of the writer + uint32_t writer_depth; // nesting of write locks + } items; + + struct dictionary_hooks *hooks; // pointer to external function callbacks to be called at certain points + struct dictionary_stats *stats; // statistics data, when DICT_OPTION_STATS is set + + DICTIONARY *master; // the master dictionary + DICTIONARY *next; // linked list for delayed destruction (garbage collection of whole dictionaries) + + uint32_t version; // the current version of the dictionary + // it is incremented when: + // - item added + // - item removed + // - item value reset + // - conflict callback returns true + // - function dictionary_version_increment() is called + + int32_t entries; // how many items are currently in the index (the linked list may have more) + int32_t referenced_items; // how many items of the dictionary are currently being used by 3rd parties + int32_t pending_deletion_items; // how many items of the dictionary have been deleted, but have not been removed yet + +#ifdef NETDATA_DICTIONARY_VALIDATE_POINTERS + netdata_mutex_t global_pointer_registry_mutex; + Pvoid_t global_pointer_registry; +#endif +}; + +// ---------------------------------------------------------------------------- +// forward definitions of functions used in reverse order in the code + +void garbage_collect_pending_deletes(DICTIONARY *dict); +static inline void item_linked_list_remove(DICTIONARY *dict, DICTIONARY_ITEM *item); +static size_t dict_item_free_with_hooks(DICTIONARY *dict, DICTIONARY_ITEM *item); +static inline const char *item_get_name(const DICTIONARY_ITEM *item); +static inline int hashtable_delete_unsafe(DICTIONARY *dict, const char *name, size_t name_len, DICTIONARY_ITEM *item); +static void item_release(DICTIONARY *dict, DICTIONARY_ITEM *item); +static bool dict_item_set_deleted(DICTIONARY *dict, DICTIONARY_ITEM *item); + +#define RC_ITEM_OK ( 0) +#define RC_ITEM_MARKED_FOR_DELETION (-1) // the item is marked for deletion +#define RC_ITEM_IS_CURRENTLY_BEING_DELETED (-2) // the item is currently being deleted +#define RC_ITEM_IS_CURRENTLY_BEING_CREATED (-3) // the item is currently being deleted +#define RC_ITEM_IS_REFERENCED (-4) // the item is currently referenced +#define item_check_and_acquire(dict, item) (item_check_and_acquire_advanced(dict, item, false) == RC_ITEM_OK) +static int item_check_and_acquire_advanced(DICTIONARY *dict, DICTIONARY_ITEM *item, bool having_index_lock); +#define item_is_not_referenced_and_can_be_removed(dict, item) (item_is_not_referenced_and_can_be_removed_advanced(dict, item) == RC_ITEM_OK) +static inline int item_is_not_referenced_and_can_be_removed_advanced(DICTIONARY *dict, DICTIONARY_ITEM *item); + +// ---------------------------------------------------------------------------- +// validate each pointer is indexed once - internal checks only + +#ifdef NETDATA_DICTIONARY_VALIDATE_POINTERS +static inline void pointer_index_init(DICTIONARY *dict __maybe_unused) { + netdata_mutex_init(&dict->global_pointer_registry_mutex); +} + +static inline void pointer_destroy_index(DICTIONARY *dict __maybe_unused) { + netdata_mutex_lock(&dict->global_pointer_registry_mutex); + JudyHSFreeArray(&dict->global_pointer_registry, PJE0); + netdata_mutex_unlock(&dict->global_pointer_registry_mutex); +} +static inline void pointer_add(DICTIONARY *dict __maybe_unused, DICTIONARY_ITEM *item __maybe_unused) { + netdata_mutex_lock(&dict->global_pointer_registry_mutex); + Pvoid_t *PValue = JudyHSIns(&dict->global_pointer_registry, &item, sizeof(void *), PJE0); + if(*PValue != NULL) + fatal("pointer already exists in registry"); + *PValue = item; + netdata_mutex_unlock(&dict->global_pointer_registry_mutex); +} + +static inline void pointer_check(DICTIONARY *dict __maybe_unused, DICTIONARY_ITEM *item __maybe_unused) { + netdata_mutex_lock(&dict->global_pointer_registry_mutex); + Pvoid_t *PValue = JudyHSGet(dict->global_pointer_registry, &item, sizeof(void *)); + if(PValue == NULL) + fatal("pointer is not found in registry"); + netdata_mutex_unlock(&dict->global_pointer_registry_mutex); +} + +static inline void pointer_del(DICTIONARY *dict __maybe_unused, DICTIONARY_ITEM *item __maybe_unused) { + netdata_mutex_lock(&dict->global_pointer_registry_mutex); + int ret = JudyHSDel(&dict->global_pointer_registry, &item, sizeof(void *), PJE0); + if(!ret) + fatal("pointer to be deleted does not exist in registry"); + netdata_mutex_unlock(&dict->global_pointer_registry_mutex); +} +#else // !NETDATA_DICTIONARY_VALIDATE_POINTERS +#define pointer_index_init(dict) debug_dummy() +#define pointer_destroy_index(dict) debug_dummy() +#define pointer_add(dict, item) debug_dummy() +#define pointer_check(dict, item) debug_dummy() +#define pointer_del(dict, item) debug_dummy() +#endif // !NETDATA_DICTIONARY_VALIDATE_POINTERS + +extern ARAL *dict_items_aral; +extern ARAL *dict_shared_items_aral; + +#include "dictionary-statistics.h" +#include "dictionary-locks.h" +#include "dictionary-refcount.h" +#include "dictionary-hashtable.h" +#include "dictionary-callbacks.h" +#include "dictionary-item.h" + +#endif //NETDATA_DICTIONARY_INTERNALS_H |