Merge branch 'sg/test-bash-version-fix'
[git.git] / alloc.c
blobe7aa81b7aa48c14f2a98894eb6e8c2e28998945e
1 /*
2 * alloc.c - specialized allocator for internal objects
4 * Copyright (C) 2006 Linus Torvalds
6 * The standard malloc/free wastes too much space for objects, partly because
7 * it maintains all the allocation infrastructure, but even more because it ends
8 * up with maximal alignment because it doesn't know what the object alignment
9 * for the new allocation is.
11 #include "cache.h"
12 #include "object.h"
13 #include "blob.h"
14 #include "tree.h"
15 #include "commit.h"
16 #include "tag.h"
17 #include "alloc.h"
19 #define BLOCKING 1024
21 union any_object {
22 struct object object;
23 struct blob blob;
24 struct tree tree;
25 struct commit commit;
26 struct tag tag;
29 struct alloc_state {
30 int count; /* total number of nodes allocated */
31 int nr; /* number of nodes left in current allocation */
32 void *p; /* first free node in current allocation */
34 /* bookkeeping of allocations */
35 void **slabs;
36 int slab_nr, slab_alloc;
39 struct alloc_state *allocate_alloc_state(void)
41 return xcalloc(1, sizeof(struct alloc_state));
44 void clear_alloc_state(struct alloc_state *s)
46 while (s->slab_nr > 0) {
47 s->slab_nr--;
48 free(s->slabs[s->slab_nr]);
51 FREE_AND_NULL(s->slabs);
54 static inline void *alloc_node(struct alloc_state *s, size_t node_size)
56 void *ret;
58 if (!s->nr) {
59 s->nr = BLOCKING;
60 s->p = xmalloc(BLOCKING * node_size);
62 ALLOC_GROW(s->slabs, s->slab_nr + 1, s->slab_alloc);
63 s->slabs[s->slab_nr++] = s->p;
65 s->nr--;
66 s->count++;
67 ret = s->p;
68 s->p = (char *)s->p + node_size;
69 memset(ret, 0, node_size);
71 return ret;
74 void *alloc_blob_node(struct repository *r)
76 struct blob *b = alloc_node(r->parsed_objects->blob_state, sizeof(struct blob));
77 b->object.type = OBJ_BLOB;
78 return b;
81 void *alloc_tree_node(struct repository *r)
83 struct tree *t = alloc_node(r->parsed_objects->tree_state, sizeof(struct tree));
84 t->object.type = OBJ_TREE;
85 return t;
88 void *alloc_tag_node(struct repository *r)
90 struct tag *t = alloc_node(r->parsed_objects->tag_state, sizeof(struct tag));
91 t->object.type = OBJ_TAG;
92 return t;
95 void *alloc_object_node(struct repository *r)
97 struct object *obj = alloc_node(r->parsed_objects->object_state, sizeof(union any_object));
98 obj->type = OBJ_NONE;
99 return obj;
102 unsigned int alloc_commit_index(struct repository *r)
104 return r->parsed_objects->commit_count++;
107 void *alloc_commit_node(struct repository *r)
109 struct commit *c = alloc_node(r->parsed_objects->commit_state, sizeof(struct commit));
110 c->object.type = OBJ_COMMIT;
111 c->index = alloc_commit_index(r);
112 c->graph_pos = COMMIT_NOT_FROM_GRAPH;
113 c->generation = GENERATION_NUMBER_INFINITY;
114 return c;
117 static void report(const char *name, unsigned int count, size_t size)
119 fprintf(stderr, "%10s: %8u (%"PRIuMAX" kB)\n",
120 name, count, (uintmax_t) size);
123 #define REPORT(name, type) \
124 report(#name, r->parsed_objects->name##_state->count, \
125 r->parsed_objects->name##_state->count * sizeof(type) >> 10)
127 void alloc_report(struct repository *r)
129 REPORT(blob, struct blob);
130 REPORT(tree, struct tree);
131 REPORT(commit, struct commit);
132 REPORT(tag, struct tag);
133 REPORT(object, union any_object);