Function Cacheus_evict

libCacheSim/cache/eviction/Cacheus.c:270–315

* @brief evict an object from the cache * it needs to call cache_evict_base before returning * which updates some metadata such as n_obj, occupied size, and hash table * * @param cache * @param req not used */

 * @param req not used
 */
static void Cacheus_evict(cache_t *cache, const request_t *req) {
  Cacheus_params_t *params = (Cacheus_params_t *)(cache->eviction_params);
  cache_t *lru = params->LRU;
  cache_t *lfu = params->LFU;
  cache_t *lru_g = params->LRU_g;
  cache_t *lfu_g = params->LFU_g;

  // If two voters decide the same:
  cache_obj_t *lru_to_evict = lru->to_evict(lru, req);
  cache_obj_t *lfu_to_evict = lfu->to_evict(lfu, req);
  DEBUG_ASSERT(lru_to_evict != NULL);
  DEBUG_ASSERT(lfu_to_evict != NULL);

  cache_obj_t *obj_to_evict = NULL;
  if (cache->to_evict_candidate_gen_vtime == cache->n_req) {
    obj_to_evict = cache->to_evict_candidate;
  } else {
    obj_to_evict = Cacheus_to_evict(cache, req);
  }

  if (lru_to_evict->obj_id == lfu_to_evict->obj_id) {
    lru->evict(lru, req);
    lfu->evict(lfu, req);
  } else if (obj_to_evict == lru_to_evict) {
    copy_cache_obj_to_request(params->req_local, obj_to_evict);
    lru->evict(lru, req);
    bool removed = lfu->remove(lfu, params->req_local->obj_id);
    DEBUG_ASSERT(removed);
    // insert into ghost
    bool ghost_hit = lru_g->get(lru_g, params->req_local);
    DEBUG_ASSERT(!ghost_hit);
  } else {
    // Remove first because LFU needs to offload the freq to obj in LRU
    // history
    copy_cache_obj_to_request(params->req_local, obj_to_evict);
    // LRU remove needs to before LFU evict
    bool removed = lru->remove(lru, params->req_local->obj_id);
    DEBUG_ASSERT(removed);
    lfu->evict(lfu, req);
    // insert into ghost
    bool ghost_hit = lfu_g->get(lfu_g, params->req_local);
    DEBUG_ASSERT(!ghost_hit);
  }

  cache->to_evict_candidate_gen_vtime = -1;
}

static bool Cacheus_remove(cache_t *cache, const obj_id_t obj_id) {
  Cacheus_params_t *params = (Cacheus_params_t *)(cache->eviction_params);