1 /*
2 * Copyright (c) 2007 Intel Corporation. All Rights Reserved.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the
6 * "Software"), to deal in the Software without restriction, including
7 * without limitation the rights to use, copy, modify, merge, publish,
8 * distribute, sub license, and/or sell copies of the Software, and to
9 * permit persons to whom the Software is furnished to do so, subject to
10 * the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the
13 * next paragraph) shall be included in all copies or substantial portions
14 * of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
19 * IN NO EVENT SHALL PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR
20 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
21 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
22 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25 #include "object_heap.h"
26
27 #include "assert.h"
28 #include <stdio.h>
29 #include <string.h>
30 #include <stdlib.h>
31
32 #define ASSERT assert
33
34 #define LAST_FREE -1
35 #define ALLOCATED -2
36
37 /*
38 * Expands the heap
39 * Return 0 on success, -1 on error
40 */
object_heap_expand(object_heap_p heap)41 static int object_heap_expand( object_heap_p heap )
42 {
43 int i;
44 void *new_heap_index;
45 int next_free;
46 int new_heap_size = heap->heap_size + heap->heap_increment;
47 int bucket_index = new_heap_size / heap->heap_increment - 1;
48
49 if (bucket_index >= heap->num_buckets) {
50 int new_num_buckets = heap->num_buckets + 8;
51 void **new_bucket;
52
53 new_bucket = realloc(heap->bucket, new_num_buckets * sizeof(void *));
54 if (NULL == new_bucket) {
55 return -1;
56 }
57
58 heap->num_buckets = new_num_buckets;
59 heap->bucket = new_bucket;
60 }
61
62 new_heap_index = (void *) malloc( heap->heap_increment * heap->object_size );
63 if ( NULL == new_heap_index )
64 {
65 return -1; /* Out of memory */
66 }
67
68 heap->bucket[bucket_index] = new_heap_index;
69 next_free = heap->next_free;
70 for(i = new_heap_size; i-- > heap->heap_size; )
71 {
72 object_base_p obj = (object_base_p) (new_heap_index + (i - heap->heap_size) * heap->object_size);
73 obj->id = i + heap->id_offset;
74 obj->next_free = next_free;
75 next_free = i;
76 }
77 heap->next_free = next_free;
78 heap->heap_size = new_heap_size;
79 return 0; /* Success */
80 }
81
82 /*
83 * Return 0 on success, -1 on error
84 */
object_heap_init(object_heap_p heap,int object_size,int id_offset)85 int object_heap_init( object_heap_p heap, int object_size, int id_offset)
86 {
87 heap->object_size = object_size;
88 heap->id_offset = id_offset & OBJECT_HEAP_OFFSET_MASK;
89 heap->heap_size = 0;
90 heap->heap_increment = 16;
91 heap->next_free = LAST_FREE;
92 heap->num_buckets = 0;
93 heap->bucket = NULL;
94
95 if (object_heap_expand(heap) == 0) {
96 ASSERT(heap->heap_size);
97 _i965InitMutex(&heap->mutex);
98 return 0;
99 } else {
100 ASSERT(!heap->heap_size);
101 ASSERT(!heap->bucket || !heap->bucket[0]);
102
103 free(heap->bucket);
104
105 return -1;
106 }
107 }
108
109 /*
110 * Allocates an object
111 * Returns the object ID on success, returns -1 on error
112 */
object_heap_allocate(object_heap_p heap)113 int object_heap_allocate( object_heap_p heap )
114 {
115 object_base_p obj;
116 int bucket_index, obj_index;
117
118 _i965LockMutex(&heap->mutex);
119 if ( LAST_FREE == heap->next_free )
120 {
121 if( -1 == object_heap_expand( heap ) )
122 {
123 _i965UnlockMutex(&heap->mutex);
124 return -1; /* Out of memory */
125 }
126 }
127 ASSERT( heap->next_free >= 0 );
128
129 bucket_index = heap->next_free / heap->heap_increment;
130 obj_index = heap->next_free % heap->heap_increment;
131
132 obj = (object_base_p) (heap->bucket[bucket_index] + obj_index * heap->object_size);
133 heap->next_free = obj->next_free;
134 _i965UnlockMutex(&heap->mutex);
135
136 obj->next_free = ALLOCATED;
137 return obj->id;
138 }
139
140 /*
141 * Lookup an object by object ID
142 * Returns a pointer to the object on success, returns NULL on error
143 */
object_heap_lookup(object_heap_p heap,int id)144 object_base_p object_heap_lookup( object_heap_p heap, int id )
145 {
146 object_base_p obj;
147 int bucket_index, obj_index;
148
149 _i965LockMutex(&heap->mutex);
150 if ( (id < heap->id_offset) || (id > (heap->heap_size+heap->id_offset)) )
151 {
152 _i965UnlockMutex(&heap->mutex);
153 return NULL;
154 }
155 id &= OBJECT_HEAP_ID_MASK;
156 bucket_index = id / heap->heap_increment;
157 obj_index = id % heap->heap_increment;
158 obj = (object_base_p) (heap->bucket[bucket_index] + obj_index * heap->object_size);
159 _i965UnlockMutex(&heap->mutex);
160
161 /* Check if the object has in fact been allocated */
162 if ( obj->next_free != ALLOCATED )
163 {
164 return NULL;
165 }
166 return obj;
167 }
168
169 /*
170 * Iterate over all objects in the heap.
171 * Returns a pointer to the first object on the heap, returns NULL if heap is empty.
172 */
object_heap_first(object_heap_p heap,object_heap_iterator * iter)173 object_base_p object_heap_first( object_heap_p heap, object_heap_iterator *iter )
174 {
175 *iter = -1;
176 return object_heap_next( heap, iter );
177 }
178
179 /*
180 * Iterate over all objects in the heap.
181 * Returns a pointer to the next object on the heap, returns NULL if heap is empty.
182 */
object_heap_next(object_heap_p heap,object_heap_iterator * iter)183 object_base_p object_heap_next( object_heap_p heap, object_heap_iterator *iter )
184 {
185 object_base_p obj;
186 int i = *iter + 1;
187 int bucket_index, obj_index;
188
189 _i965LockMutex(&heap->mutex);
190 while ( i < heap->heap_size)
191 {
192 bucket_index = i / heap->heap_increment;
193 obj_index = i % heap->heap_increment;
194
195 obj = (object_base_p) (heap->bucket[bucket_index] + obj_index * heap->object_size);
196 if (obj->next_free == ALLOCATED)
197 {
198 _i965UnlockMutex(&heap->mutex);
199 *iter = i;
200 return obj;
201 }
202 i++;
203 }
204 _i965UnlockMutex(&heap->mutex);
205 *iter = i;
206 return NULL;
207 }
208
209
210
211 /*
212 * Frees an object
213 */
object_heap_free(object_heap_p heap,object_base_p obj)214 void object_heap_free( object_heap_p heap, object_base_p obj )
215 {
216 /* Don't complain about NULL pointers */
217 if (NULL != obj)
218 {
219 /* Check if the object has in fact been allocated */
220 ASSERT( obj->next_free == ALLOCATED );
221
222 _i965LockMutex(&heap->mutex);
223 obj->next_free = heap->next_free;
224 heap->next_free = obj->id & OBJECT_HEAP_ID_MASK;
225 _i965UnlockMutex(&heap->mutex);
226 }
227 }
228
229 /*
230 * Destroys a heap, the heap must be empty.
231 */
object_heap_destroy(object_heap_p heap)232 void object_heap_destroy( object_heap_p heap )
233 {
234 object_base_p obj;
235 int i;
236 int bucket_index, obj_index;
237
238 if (heap->heap_size) {
239 _i965DestroyMutex(&heap->mutex);
240
241 /* Check if heap is empty */
242 for (i = 0; i < heap->heap_size; i++)
243 {
244 /* Check if object is not still allocated */
245 bucket_index = i / heap->heap_increment;
246 obj_index = i % heap->heap_increment;
247 obj = (object_base_p) (heap->bucket[bucket_index] + obj_index * heap->object_size);
248 ASSERT( obj->next_free != ALLOCATED );
249 }
250
251 for (i = 0; i < heap->heap_size / heap->heap_increment; i++) {
252 free(heap->bucket[i]);
253 }
254
255 free(heap->bucket);
256 }
257
258 heap->bucket = NULL;
259 heap->heap_size = 0;
260 heap->next_free = LAST_FREE;
261 }
262