1 /**
2 * @file db_insert.c
3 * Inserting a key-value pair into a DB
4 *
5 * @remark Copyright 2002 OProfile authors
6 * @remark Read the file COPYING
7 *
8 * @author Philippe Elie
9 */
10
11 #define _GNU_SOURCE
12
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 #include <errno.h>
17
18 #include "odb.h"
19
20
add_node(odb_data_t * data,odb_key_t key,odb_value_t value)21 static inline int add_node(odb_data_t * data, odb_key_t key, odb_value_t value)
22 {
23 odb_index_t new_node;
24 odb_node_t * node;
25 odb_index_t index;
26
27 /* no locking is necessary: iteration interface retrieve data through
28 * the node_base array, we doesn't increase current_size now but it's
29 * done by odb_commit_reservation() so the new slot is visible only
30 * after the increment
31 */
32 if (data->descr->current_size >= data->descr->size) {
33 if (odb_grow_hashtable(data))
34 return EINVAL;
35 }
36 new_node = data->descr->current_size;
37
38 node = &data->node_base[new_node];
39 node->value = value;
40 node->key = key;
41
42 index = odb_do_hash(data, key);
43 node->next = data->hash_base[index];
44 data->hash_base[index] = new_node;
45
46 /* FIXME: we need wrmb() here */
47 odb_commit_reservation(data);
48
49 return 0;
50 }
51
odb_update_node(odb_t * odb,odb_key_t key)52 int odb_update_node(odb_t * odb, odb_key_t key)
53 {
54 return odb_update_node_with_offset(odb, key, 1);
55 }
56
odb_update_node_with_offset(odb_t * odb,odb_key_t key,unsigned long int offset)57 int odb_update_node_with_offset(odb_t * odb,
58 odb_key_t key,
59 unsigned long int offset)
60 {
61 odb_index_t index;
62 odb_node_t * node;
63 odb_data_t * data;
64
65 data = odb->data;
66 index = data->hash_base[odb_do_hash(data, key)];
67 while (index) {
68 node = &data->node_base[index];
69 if (node->key == key) {
70 if (node->value + offset != 0) {
71 node->value += offset;
72 } else {
73 /* post profile tools must handle overflow */
74 /* FIXME: the tricky way will be just to add
75 * a goto to jump right before the return
76 * add_node(), in this way we no longer can
77 * overflow. It'll work because new node are
78 * linked at the start of the node list for
79 * this bucket so this loop will see first a
80 * non overflowed node if one exist. When we
81 * grow the hashtable the most recently
82 * allocated node for this key will be setup
83 * last, so again it'll be linked at start of
84 * the list. pp tools looke like ok with this
85 * change.
86 *
87 * This change doesn't involve any file format
88 * change but perhaps it's a bit hacky to do
89 * this w/o bumping the sample file format
90 * version. The drawback of this is the added
91 * node are additive not multiplicative.
92 * (multiplicative as if we add more bits to
93 * store a value)
94 */
95 }
96 return 0;
97 }
98
99 index = node->next;
100 }
101
102 return add_node(data, key, offset);
103 }
104
105
odb_add_node(odb_t * odb,odb_key_t key,odb_value_t value)106 int odb_add_node(odb_t * odb, odb_key_t key, odb_value_t value)
107 {
108 return add_node(odb->data, key, value);
109 }
110