int cache_insert(PageCache *cache, uint64_t addr, const uint8_t *pdata, uint64_t current_age) { CacheItem *it; /* actual update of entry */ it = cache_get_by_addr(cache, addr); if (it->it_data && it->it_addr != addr && it->it_age + CACHED_PAGE_LIFETIME > current_age) { /* the cache page is fresh, don't replace it */ return -1; } /* allocate page */ if (!it->it_data) { it->it_data = g_try_malloc(cache->page_size); if (!it->it_data) { DPRINTF("Error allocating page\n"); return -1; } cache->num_items++; } memcpy(it->it_data, pdata, cache->page_size); it->it_age = current_age; it->it_addr = addr; return 0; }
int64_t cache_resize(PageCache *cache, int64_t new_num_pages) { PageCache *new_cache; int64_t i; CacheItem *old_it, *new_it; g_assert(cache); /* cache was not inited */ if (cache->page_cache == NULL) { return -1; } /* same size */ if (pow2floor(new_num_pages) == cache->max_num_items) { return cache->max_num_items; } new_cache = cache_init(new_num_pages, cache->page_size); if (!(new_cache)) { DPRINTF("Error creating new cache\n"); return -1; } /* move all data from old cache */ for (i = 0; i < cache->max_num_items; i++) { old_it = &cache->page_cache[i]; if (old_it->it_addr != -1) { /* check for collision, if there is, keep MRU page */ new_it = cache_get_by_addr(new_cache, old_it->it_addr); if (new_it->it_data) { /* keep the MRU page */ if (new_it->it_age >= old_it->it_age) { g_free(old_it->it_data); } else { g_free(new_it->it_data); new_it->it_data = old_it->it_data; new_it->it_age = old_it->it_age; new_it->it_addr = old_it->it_addr; } } else { cache_insert(new_cache, old_it->it_addr, old_it->it_data); } } } g_free(cache->page_cache); cache->page_cache = new_cache->page_cache; cache->max_num_items = new_cache->max_num_items; cache->num_items = new_cache->num_items; g_free(new_cache); return cache->max_num_items; }
bool cache_is_cached(const PageCache *cache, uint64_t addr, uint64_t current_age) { CacheItem *it; it = cache_get_by_addr(cache, addr); if (it->it_addr == addr) { /* update the it_age when the cache hit */ it->it_age = current_age; return true; } return false; }
void cache_insert(PageCache *cache, uint64_t addr, uint8_t *pdata) { CacheItem *it = NULL; g_assert(cache); g_assert(cache->page_cache); /* actual update of entry */ it = cache_get_by_addr(cache, addr); /* free old cached data if any */ g_free(it->it_data); if (!it->it_data) { cache->num_items++; } it->it_data = pdata; it->it_age = ++cache->max_item_age; it->it_addr = addr; }
uint8_t *get_cached_data(const PageCache *cache, uint64_t addr) { return cache_get_by_addr(cache, addr)->it_data; }