dep/jemalloc/src/rtree.c

   1 #define RTREE_C_
   2 #include "jemalloc/internal/jemalloc_internal.h"
   3
   4 rtree_t *
   5 rtree_new(unsigned bits)
   6 {
   7         rtree_t *ret;
   8         unsigned bits_per_level, height, i;
   9
  10         bits_per_level = ffs(pow2_ceil((RTREE_NODESIZE / sizeof(void *)))) - 1;
  11         height = bits / bits_per_level;
  12         if (height * bits_per_level != bits)
  13                 height++;
  14         assert(height * bits_per_level >= bits);
  15
  16         ret = (rtree_t*)base_alloc(offsetof(rtree_t, level2bits) +
  17             (sizeof(unsigned) * height));
  18         if (ret == NULL)
  19                 return (NULL);
  20         memset(ret, 0, offsetof(rtree_t, level2bits) + (sizeof(unsigned) *
  21             height));
  22
  23         malloc_mutex_init(&ret->mutex);
  24         ret->height = height;
  25         if (bits_per_level * height > bits)
  26                 ret->level2bits[0] = bits % bits_per_level;
  27         else
  28                 ret->level2bits[0] = bits_per_level;
  29         for (i = 1; i < height; i++)
  30                 ret->level2bits[i] = bits_per_level;
  31
  32         ret->root = (void**)base_alloc(sizeof(void *) << ret->level2bits[0]);
  33         if (ret->root == NULL) {
  34                 /*
  35                  * We leak the rtree here, since there's no generic base
  36                  * deallocation.
  37                  */
  38                 return (NULL);
  39         }
  40         memset(ret->root, 0, sizeof(void *) << ret->level2bits[0]);
  41
  42         return (ret);
  43 }