Exemplo n.º 1
0
/**
 * Empty the cache. Useful when there is not enough memory.
 */
void
pb_cache_release_all_buffers(struct pb_cache *mgr)
{
   struct list_head *curr, *next;
   struct pb_cache_entry *buf;

   pipe_mutex_lock(mgr->mutex);
   curr = mgr->cache.next;
   next = curr->next;
   while (curr != &mgr->cache) {
      buf = LIST_ENTRY(struct pb_cache_entry, curr, head);
      destroy_buffer_locked(buf);
      curr = next;
      next = curr->next;
   }
   pipe_mutex_unlock(mgr->mutex);
}
Exemplo n.º 2
0
/**
 * Empty the cache. Useful when there is not enough memory.
 */
void
pb_cache_release_all_buffers(struct pb_cache *mgr)
{
   struct list_head *curr, *next;
   struct pb_cache_entry *buf;
   unsigned i;

   pipe_mutex_lock(mgr->mutex);
   for (i = 0; i < ARRAY_SIZE(mgr->buckets); i++) {
      struct list_head *cache = &mgr->buckets[i];

      curr = cache->next;
      next = curr->next;
      while (curr != cache) {
         buf = LIST_ENTRY(struct pb_cache_entry, curr, head);
         destroy_buffer_locked(buf);
         curr = next;
         next = curr->next;
      }
   }
   pipe_mutex_unlock(mgr->mutex);
}
Exemplo n.º 3
0
/**
 * Free as many cache buffers from the list head as possible.
 */
static void
release_expired_buffers_locked(struct list_head *cache)
{
   struct list_head *curr, *next;
   struct pb_cache_entry *entry;
   int64_t now;

   now = os_time_get();

   curr = cache->next;
   next = curr->next;
   while (curr != cache) {
      entry = LIST_ENTRY(struct pb_cache_entry, curr, head);

      if (!os_time_timeout(entry->start, entry->end, now))
         break;

      destroy_buffer_locked(entry);

      curr = next;
      next = curr->next;
   }
}
Exemplo n.º 4
0
/**
 * Find a compatible buffer in the cache, return it, and remove it
 * from the cache.
 */
struct pb_buffer *
pb_cache_reclaim_buffer(struct pb_cache *mgr, pb_size size,
                        unsigned alignment, unsigned usage,
                        unsigned bucket_index)
{
   struct pb_cache_entry *entry;
   struct pb_cache_entry *cur_entry;
   struct list_head *cur, *next;
   int64_t now;
   int ret = 0;
   struct list_head *cache = &mgr->buckets[bucket_index];

   pipe_mutex_lock(mgr->mutex);

   entry = NULL;
   cur = cache->next;
   next = cur->next;

   /* search in the expired buffers, freeing them in the process */
   now = os_time_get();
   while (cur != cache) {
      cur_entry = LIST_ENTRY(struct pb_cache_entry, cur, head);

      if (!entry && (ret = pb_cache_is_buffer_compat(cur_entry, size,
                                                     alignment, usage) > 0))
         entry = cur_entry;
      else if (os_time_timeout(cur_entry->start, cur_entry->end, now))
         destroy_buffer_locked(cur_entry);
      else
         /* This buffer (and all hereafter) are still hot in cache */
         break;

      /* the buffer is busy (and probably all remaining ones too) */
      if (ret == -1)
         break;

      cur = next;
      next = cur->next;
   }

   /* keep searching in the hot buffers */
   if (!entry && ret != -1) {
      while (cur != cache) {
         cur_entry = LIST_ENTRY(struct pb_cache_entry, cur, head);
         ret = pb_cache_is_buffer_compat(cur_entry, size, alignment, usage);

         if (ret > 0) {
            entry = cur_entry;
            break;
         }
         if (ret == -1)
            break;
         /* no need to check the timeout here */
         cur = next;
         next = cur->next;
      }
   }

   /* found a compatible buffer, return it */
   if (entry) {
      struct pb_buffer *buf = entry->buffer;

      mgr->cache_size -= buf->size;
      LIST_DEL(&entry->head);
      --mgr->num_buffers;
      pipe_mutex_unlock(mgr->mutex);
      /* Increase refcount */
      pipe_reference_init(&buf->reference, 1);
      return buf;
   }

   pipe_mutex_unlock(mgr->mutex);
   return NULL;
}