summaryrefslogtreecommitdiffstats
path: root/src/base.c
blob: 01c62df4f1f2146db2a4cb4b8c7c497410cb336c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
#define	JEMALLOC_BASE_C_
#include "jemalloc/internal/jemalloc_internal.h"

/******************************************************************************/
/* Data. */

static malloc_mutex_t	base_mtx;
static extent_tree_t	base_avail_szad;
static extent_node_t	*base_nodes;
static size_t		base_allocated;

/******************************************************************************/

/* base_mtx must be held. */
static extent_node_t *
base_node_try_alloc(void)
{
	extent_node_t *node;

	if (base_nodes == NULL)
		return (NULL);
	node = base_nodes;
	base_nodes = *(extent_node_t **)node;
	JEMALLOC_VALGRIND_MAKE_MEM_UNDEFINED(node, sizeof(extent_node_t));
	return (node);
}

/* base_mtx must be held. */
static void
base_node_dalloc(extent_node_t *node)
{

	JEMALLOC_VALGRIND_MAKE_MEM_UNDEFINED(node, sizeof(extent_node_t));
	*(extent_node_t **)node = base_nodes;
	base_nodes = node;
}

/* base_mtx must be held. */
static extent_node_t *
base_chunk_alloc(size_t minsize)
{
	extent_node_t *node;
	size_t csize, nsize;
	void *addr;

	assert(minsize != 0);
	node = base_node_try_alloc();
	/* Allocate enough space to also carve a node out if necessary. */
	nsize = (node == NULL) ? CACHELINE_CEILING(sizeof(extent_node_t)) : 0;
	csize = CHUNK_CEILING(minsize + nsize);
	addr = chunk_alloc_base(csize);
	if (addr == NULL) {
		if (node != NULL)
			base_node_dalloc(node);
		return (NULL);
	}
	if (node == NULL) {
		csize -= nsize;
		node = (extent_node_t *)((uintptr_t)addr + csize);
		if (config_stats)
			base_allocated += nsize;
	}
	extent_node_init(node, NULL, addr, csize, true);
	return (node);
}

/*
 * base_alloc() guarantees demand-zeroed memory, in order to make multi-page
 * sparse data structures such as radix tree nodes efficient with respect to
 * physical memory usage.
 */
void *
base_alloc(size_t size)
{
	void *ret;
	size_t csize, usize;
	extent_node_t *node;
	extent_node_t key;

	/*
	 * Round size up to nearest multiple of the cacheline size, so that
	 * there is no chance of false cache line sharing.
	 */
	csize = CACHELINE_CEILING(size);

	usize = s2u(csize);
	extent_node_init(&key, NULL, NULL, usize, false);
	malloc_mutex_lock(&base_mtx);
	node = extent_tree_szad_nsearch(&base_avail_szad, &key);
	if (node != NULL) {
		/* Use existing space. */
		extent_tree_szad_remove(&base_avail_szad, node);
	} else {
		/* Try to allocate more space. */
		node = base_chunk_alloc(csize);
	}
	if (node == NULL) {
		ret = NULL;
		goto label_return;
	}

	ret = extent_node_addr_get(node);
	if (extent_node_size_get(node) > csize) {
		extent_node_addr_set(node, (void *)((uintptr_t)ret + csize));
		extent_node_size_set(node, extent_node_size_get(node) - csize);
		extent_tree_szad_insert(&base_avail_szad, node);
	} else
		base_node_dalloc(node);
	if (config_stats)
		base_allocated += csize;
	JEMALLOC_VALGRIND_MAKE_MEM_UNDEFINED(ret, csize);
label_return:
	malloc_mutex_unlock(&base_mtx);
	return (ret);
}

size_t
base_allocated_get(void)
{
	size_t ret;

	malloc_mutex_lock(&base_mtx);
	ret = base_allocated;
	malloc_mutex_unlock(&base_mtx);
	return (ret);
}

bool
base_boot(void)
{

	if (malloc_mutex_init(&base_mtx))
		return (true);
	extent_tree_szad_new(&base_avail_szad);
	base_nodes = NULL;

	return (false);
}

void
base_prefork(void)
{

	malloc_mutex_prefork(&base_mtx);
}

void
base_postfork_parent(void)
{

	malloc_mutex_postfork_parent(&base_mtx);
}

void
base_postfork_child(void)
{

	malloc_mutex_postfork_child(&base_mtx);
}