io_uring/alloc_cache.h

   1 #ifndef IOU_ALLOC_CACHE_H
   2 #define IOU_ALLOC_CACHE_H
   3
   4 /*
   5  * Don't allow the cache to grow beyond this size.
   6  */
   7 #define IO_ALLOC_CACHE_MAX      512
   8
   9 struct io_cache_entry {
  10         struct io_wq_work_node node;
  11 };
  12
  13 static inline bool io_alloc_cache_put(struct io_alloc_cache *cache,
  14                                       struct io_cache_entry *entry)
  15 {
  16         if (cache->nr_cached < cache->max_cached) {
  17                 cache->nr_cached++;
  18                 wq_stack_add_head(&entry->node, &cache->list);
  19                 kasan_mempool_poison_object(entry);
  20                 return true;
  21         }
  22         return false;
  23 }
  24
  25 static inline bool io_alloc_cache_empty(struct io_alloc_cache *cache)
  26 {
  27         return !cache->list.next;
  28 }
  29
  30 static inline struct io_cache_entry *io_alloc_cache_get(struct io_alloc_cache *cache)
  31 {
  32         if (cache->list.next) {
  33                 struct io_cache_entry *entry;
  34
  35                 entry = container_of(cache->list.next, struct io_cache_entry, node);
  36                 kasan_mempool_unpoison_object(entry, cache->elem_size);
  37                 cache->list.next = cache->list.next->next;
  38                 cache->nr_cached--;
  39                 return entry;
  40         }
  41
  42         return NULL;
  43 }
  44
  45 static inline void io_alloc_cache_init(struct io_alloc_cache *cache,
  46                                        unsigned max_nr, size_t size)
  47 {
  48         cache->list.next = NULL;
  49         cache->nr_cached = 0;
  50         cache->max_cached = max_nr;
  51         cache->elem_size = size;
  52 }
  53
  54 static inline void io_alloc_cache_free(struct io_alloc_cache *cache,
  55                                         void (*free)(struct io_cache_entry *))
  56 {
  57         while (1) {
  58                 struct io_cache_entry *entry = io_alloc_cache_get(cache);
  59
  60                 if (!entry)
  61                         break;
  62                 free(entry);
  63         }
  64         cache->nr_cached = 0;
  65 }
  66 #endif