xref: /freebsd/contrib/jemalloc/src/rtree.c (revision a4bd5210d5e680818a9319a76ebf71caef95bcd3)
1*a4bd5210SJason Evans #define	JEMALLOC_RTREE_C_
2*a4bd5210SJason Evans #include "jemalloc/internal/jemalloc_internal.h"
3*a4bd5210SJason Evans 
4*a4bd5210SJason Evans rtree_t *
5*a4bd5210SJason Evans rtree_new(unsigned bits)
6*a4bd5210SJason Evans {
7*a4bd5210SJason Evans 	rtree_t *ret;
8*a4bd5210SJason Evans 	unsigned bits_per_level, height, i;
9*a4bd5210SJason Evans 
10*a4bd5210SJason Evans 	bits_per_level = ffs(pow2_ceil((RTREE_NODESIZE / sizeof(void *)))) - 1;
11*a4bd5210SJason Evans 	height = bits / bits_per_level;
12*a4bd5210SJason Evans 	if (height * bits_per_level != bits)
13*a4bd5210SJason Evans 		height++;
14*a4bd5210SJason Evans 	assert(height * bits_per_level >= bits);
15*a4bd5210SJason Evans 
16*a4bd5210SJason Evans 	ret = (rtree_t*)base_alloc(offsetof(rtree_t, level2bits) +
17*a4bd5210SJason Evans 	    (sizeof(unsigned) * height));
18*a4bd5210SJason Evans 	if (ret == NULL)
19*a4bd5210SJason Evans 		return (NULL);
20*a4bd5210SJason Evans 	memset(ret, 0, offsetof(rtree_t, level2bits) + (sizeof(unsigned) *
21*a4bd5210SJason Evans 	    height));
22*a4bd5210SJason Evans 
23*a4bd5210SJason Evans 	if (malloc_mutex_init(&ret->mutex)) {
24*a4bd5210SJason Evans 		/* Leak the rtree. */
25*a4bd5210SJason Evans 		return (NULL);
26*a4bd5210SJason Evans 	}
27*a4bd5210SJason Evans 	ret->height = height;
28*a4bd5210SJason Evans 	if (bits_per_level * height > bits)
29*a4bd5210SJason Evans 		ret->level2bits[0] = bits % bits_per_level;
30*a4bd5210SJason Evans 	else
31*a4bd5210SJason Evans 		ret->level2bits[0] = bits_per_level;
32*a4bd5210SJason Evans 	for (i = 1; i < height; i++)
33*a4bd5210SJason Evans 		ret->level2bits[i] = bits_per_level;
34*a4bd5210SJason Evans 
35*a4bd5210SJason Evans 	ret->root = (void**)base_alloc(sizeof(void *) << ret->level2bits[0]);
36*a4bd5210SJason Evans 	if (ret->root == NULL) {
37*a4bd5210SJason Evans 		/*
38*a4bd5210SJason Evans 		 * We leak the rtree here, since there's no generic base
39*a4bd5210SJason Evans 		 * deallocation.
40*a4bd5210SJason Evans 		 */
41*a4bd5210SJason Evans 		return (NULL);
42*a4bd5210SJason Evans 	}
43*a4bd5210SJason Evans 	memset(ret->root, 0, sizeof(void *) << ret->level2bits[0]);
44*a4bd5210SJason Evans 
45*a4bd5210SJason Evans 	return (ret);
46*a4bd5210SJason Evans }
47