text: /*
   * Copyright 2018 Lenovo
   *
   * Licensed under the BSD-3 license. see LICENSE.Lenovo.txt for full text
   */
  /*
   * Note:
   *   Codes enclosed in `#ifdef PSLAB' and `#endif' are added by Lenovo for
   *   persistent memory support
   */
  #define HOT_LRU 0
  #define WARM_LRU 64
  #define COLD_LRU 128
  #define TEMP_LRU 192
  
  #define CLEAR_LRU(id) (id & ~(3<<6))
  #define GET_LRU(id) (id & (3<<6))
  
  /* See items.c */
  uint64_t get_cas_id(void);
  
  /*@null@*/
  item *do_item_alloc(char *key, const size_t nkey, const unsigned int flags, const rel_time_t exptime, const int nbytes);
  item_chunk *do_item_alloc_chunk(item_chunk *ch, const size_t bytes_remain);
  item *do_item_alloc_pull(const size_t ntotal, const unsigned int id);
  void item_free(item *it);
  bool item_size_ok(const size_t nkey, const int flags, const int nbytes);
  
  int  do_item_link(item *it, const uint32_t hv);     /** may fail if transgresses limits */
  #ifdef PSLAB
  void do_item_relink(item *it, const uint32_t hv);
  #endif
  void do_item_unlink(item *it, const uint32_t hv);
  void do_item_unlink_nolock(item *it, const uint32_t hv);
  void do_item_remove(item *it);
  void do_item_update(item *it);   /** update LRU time to current and reposition */
  void do_item_update_nolock(item *it);
  int  do_item_replace(item *it, item *new_it, const uint32_t hv);
  
  int item_is_flushed(item *it);
  
  void do_item_linktail_q(item *it);
  void do_item_unlinktail_q(item *it);
  item *do_item_crawl_q(item *it);
  
  void *item_lru_bump_buf_create(void);
  
  #define LRU_PULL_EVICT 1
  #define LRU_PULL_CRAWL_BLOCKS 2
  #define LRU_PULL_RETURN_ITEM 4 /* fill info struct if available */
  
  struct lru_pull_tail_return {
      item *it;
      uint32_t hv;
  };
  
  int lru_pull_tail(const int orig_id, const int cur_lru,
          const uint64_t total_bytes, const uint8_t flags, const rel_time_t max_age,
          struct lru_pull_tail_return *ret_it);
  
  /*@null@*/
  char *item_cachedump(const unsigned int slabs_clsid, const unsigned int limit, unsigned int *bytes);
  void item_stats(ADD_STAT add_stats, void *c);
  void do_item_stats_add_crawl(const int i, const uint64_t reclaimed,
          const uint64_t unfetched, const uint64_t checked);
  void item_stats_totals(ADD_STAT add_stats, void *c);
  /*@null@*/
  void item_stats_sizes(ADD_STAT add_stats, void *c);
  void item_stats_sizes_init(void);
  void item_stats_sizes_enable(ADD_STAT add_stats, void *c);
  void item_stats_sizes_disable(ADD_STAT add_stats, void *c);
  void item_stats_sizes_add(item *it);
  void item_stats_sizes_remove(item *it);
  bool item_stats_sizes_status(void);
  
  /* stats getter for slab automover */
  typedef struct {
      int64_t evicted;
      int64_t outofmemory;
      uint32_t age;
  } item_stats_automove;
  void fill_item_stats_automove(item_stats_automove *am);
  
  item *do_item_get(const char *key, const size_t nkey, const uint32_t hv, conn *c, const bool do_update);
  item *do_item_touch(const char *key, const size_t nkey, uint32_t exptime, const uint32_t hv, conn *c);
  void item_stats_reset(void);
  extern pthread_mutex_t lru_locks[POWER_LARGEST];
  
  int start_lru_maintainer_thread(void *arg);
  int stop_lru_maintainer_thread(void);
  int init_lru_maintainer(void);
  void lru_maintainer_pause(void);
  void lru_maintainer_resume(void);
  
  void *lru_bump_buf_create(void);
  
  #ifdef EXTSTORE
  #define STORAGE_delete(e, it) \
      do { \
          if (it->it_flags & ITEM_HDR) { \
              item_hdr *hdr = (item_hdr *)ITEM_data(it); \
              extstore_delete(e, hdr->page_id, hdr->page_version, \
                      1, ITEM_ntotal(it)); \
          } \
      } while (0)
  #else
  #define STORAGE_delete(...)
  #endif
  