xref: /freebsd/contrib/jemalloc/src/rtree.c (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
1 #define	JEMALLOC_RTREE_C_
2 #include "jemalloc/internal/jemalloc_internal.h"
3 
4 rtree_t *
5 rtree_new(unsigned bits, rtree_alloc_t *alloc, rtree_dalloc_t *dalloc)
6 {
7 	rtree_t *ret;
8 	unsigned bits_per_level, bits_in_leaf, height, i;
9 
10 	assert(bits > 0 && bits <= (sizeof(uintptr_t) << 3));
11 
12 	bits_per_level = ffs(pow2_ceil((RTREE_NODESIZE / sizeof(void *)))) - 1;
13 	bits_in_leaf = ffs(pow2_ceil((RTREE_NODESIZE / sizeof(uint8_t)))) - 1;
14 	if (bits > bits_in_leaf) {
15 		height = 1 + (bits - bits_in_leaf) / bits_per_level;
16 		if ((height-1) * bits_per_level + bits_in_leaf != bits)
17 			height++;
18 	} else {
19 		height = 1;
20 	}
21 	assert((height-1) * bits_per_level + bits_in_leaf >= bits);
22 
23 	ret = (rtree_t*)alloc(offsetof(rtree_t, level2bits) +
24 	    (sizeof(unsigned) * height));
25 	if (ret == NULL)
26 		return (NULL);
27 	memset(ret, 0, offsetof(rtree_t, level2bits) + (sizeof(unsigned) *
28 	    height));
29 
30 	ret->alloc = alloc;
31 	ret->dalloc = dalloc;
32 	if (malloc_mutex_init(&ret->mutex)) {
33 		if (dalloc != NULL)
34 			dalloc(ret);
35 		return (NULL);
36 	}
37 	ret->height = height;
38 	if (height > 1) {
39 		if ((height-1) * bits_per_level + bits_in_leaf > bits) {
40 			ret->level2bits[0] = (bits - bits_in_leaf) %
41 			    bits_per_level;
42 		} else
43 			ret->level2bits[0] = bits_per_level;
44 		for (i = 1; i < height-1; i++)
45 			ret->level2bits[i] = bits_per_level;
46 		ret->level2bits[height-1] = bits_in_leaf;
47 	} else
48 		ret->level2bits[0] = bits;
49 
50 	ret->root = (void**)alloc(sizeof(void *) << ret->level2bits[0]);
51 	if (ret->root == NULL) {
52 		if (dalloc != NULL)
53 			dalloc(ret);
54 		return (NULL);
55 	}
56 	memset(ret->root, 0, sizeof(void *) << ret->level2bits[0]);
57 
58 	return (ret);
59 }
60 
61 static void
62 rtree_delete_subtree(rtree_t *rtree, void **node, unsigned level)
63 {
64 
65 	if (level < rtree->height - 1) {
66 		size_t nchildren, i;
67 
68 		nchildren = ZU(1) << rtree->level2bits[level];
69 		for (i = 0; i < nchildren; i++) {
70 			void **child = (void **)node[i];
71 			if (child != NULL)
72 				rtree_delete_subtree(rtree, child, level + 1);
73 		}
74 	}
75 	rtree->dalloc(node);
76 }
77 
78 void
79 rtree_delete(rtree_t *rtree)
80 {
81 
82 	rtree_delete_subtree(rtree, rtree->root, 0);
83 	rtree->dalloc(rtree);
84 }
85 
86 void
87 rtree_prefork(rtree_t *rtree)
88 {
89 
90 	malloc_mutex_prefork(&rtree->mutex);
91 }
92 
93 void
94 rtree_postfork_parent(rtree_t *rtree)
95 {
96 
97 	malloc_mutex_postfork_parent(&rtree->mutex);
98 }
99 
100 void
101 rtree_postfork_child(rtree_t *rtree)
102 {
103 
104 	malloc_mutex_postfork_child(&rtree->mutex);
105 }
106