1 | /** |
---|
2 | * @file |
---|
3 | * |
---|
4 | * @ingroup RTEMSScoreHeap |
---|
5 | * |
---|
6 | * @brief Heap Handler implementation. |
---|
7 | */ |
---|
8 | |
---|
9 | /* |
---|
10 | * COPYRIGHT (c) 1989-1999. |
---|
11 | * On-Line Applications Research Corporation (OAR). |
---|
12 | * |
---|
13 | * Copyright (c) 2009 embedded brains GmbH. |
---|
14 | * |
---|
15 | * The license and distribution terms for this file may be |
---|
16 | * found in the file LICENSE in this distribution or at |
---|
17 | * http://www.rtems.org/license/LICENSE. |
---|
18 | */ |
---|
19 | |
---|
20 | #if HAVE_CONFIG_H |
---|
21 | #include "config.h" |
---|
22 | #endif |
---|
23 | |
---|
24 | #include <rtems/score/heapimpl.h> |
---|
25 | |
---|
26 | #ifndef HEAP_PROTECTION |
---|
27 | #define _Heap_Protection_free_delayed_blocks( heap, alloc_begin ) false |
---|
28 | #else |
---|
29 | static bool _Heap_Protection_free_delayed_blocks( |
---|
30 | Heap_Control *heap, |
---|
31 | uintptr_t alloc_begin |
---|
32 | ) |
---|
33 | { |
---|
34 | bool search_again = false; |
---|
35 | uintptr_t const blocks_to_free_count = |
---|
36 | (heap->Protection.delayed_free_block_count |
---|
37 | + heap->Protection.delayed_free_fraction - 1) |
---|
38 | / heap->Protection.delayed_free_fraction; |
---|
39 | |
---|
40 | if ( alloc_begin == 0 && blocks_to_free_count > 0 ) { |
---|
41 | Heap_Block *block_to_free = heap->Protection.first_delayed_free_block; |
---|
42 | uintptr_t count = 0; |
---|
43 | |
---|
44 | for ( count = 0; count < blocks_to_free_count; ++count ) { |
---|
45 | Heap_Block *next_block_to_free; |
---|
46 | |
---|
47 | if ( !_Heap_Is_block_in_heap( heap, block_to_free ) ) { |
---|
48 | _Heap_Protection_block_error( |
---|
49 | heap, |
---|
50 | block_to_free, |
---|
51 | HEAP_ERROR_BAD_FREE_BLOCK |
---|
52 | ); |
---|
53 | } |
---|
54 | |
---|
55 | next_block_to_free = |
---|
56 | block_to_free->Protection_begin.next_delayed_free_block; |
---|
57 | block_to_free->Protection_begin.next_delayed_free_block = |
---|
58 | HEAP_PROTECTION_OBOLUS; |
---|
59 | |
---|
60 | _Heap_Free( |
---|
61 | heap, |
---|
62 | (void *) _Heap_Alloc_area_of_block( block_to_free ) |
---|
63 | ); |
---|
64 | |
---|
65 | block_to_free = next_block_to_free; |
---|
66 | } |
---|
67 | |
---|
68 | heap->Protection.delayed_free_block_count -= blocks_to_free_count; |
---|
69 | heap->Protection.first_delayed_free_block = block_to_free; |
---|
70 | |
---|
71 | search_again = true; |
---|
72 | } |
---|
73 | |
---|
74 | return search_again; |
---|
75 | } |
---|
76 | #endif |
---|
77 | |
---|
78 | #ifdef RTEMS_HEAP_DEBUG |
---|
79 | static void _Heap_Check_allocation( |
---|
80 | const Heap_Control *heap, |
---|
81 | const Heap_Block *block, |
---|
82 | uintptr_t alloc_begin, |
---|
83 | uintptr_t alloc_size, |
---|
84 | uintptr_t alignment, |
---|
85 | uintptr_t boundary |
---|
86 | ) |
---|
87 | { |
---|
88 | uintptr_t const min_block_size = heap->min_block_size; |
---|
89 | uintptr_t const page_size = heap->page_size; |
---|
90 | |
---|
91 | uintptr_t const block_begin = (uintptr_t) block; |
---|
92 | uintptr_t const block_size = _Heap_Block_size( block ); |
---|
93 | uintptr_t const block_end = block_begin + block_size; |
---|
94 | |
---|
95 | uintptr_t const alloc_end = alloc_begin + alloc_size; |
---|
96 | |
---|
97 | uintptr_t const alloc_area_begin = _Heap_Alloc_area_of_block( block ); |
---|
98 | uintptr_t const alloc_area_offset = alloc_begin - alloc_area_begin; |
---|
99 | |
---|
100 | _HAssert( block_size >= min_block_size ); |
---|
101 | _HAssert( block_begin < block_end ); |
---|
102 | _HAssert( |
---|
103 | _Heap_Is_aligned( block_begin + HEAP_BLOCK_HEADER_SIZE, page_size ) |
---|
104 | ); |
---|
105 | _HAssert( |
---|
106 | _Heap_Is_aligned( block_size, page_size ) |
---|
107 | ); |
---|
108 | |
---|
109 | _HAssert( alloc_end <= block_end + HEAP_ALLOC_BONUS ); |
---|
110 | _HAssert( alloc_area_begin == block_begin + HEAP_BLOCK_HEADER_SIZE); |
---|
111 | _HAssert( alloc_area_offset < page_size ); |
---|
112 | |
---|
113 | _HAssert( _Heap_Is_aligned( alloc_area_begin, page_size ) ); |
---|
114 | if ( alignment == 0 ) { |
---|
115 | _HAssert( alloc_begin == alloc_area_begin ); |
---|
116 | } else { |
---|
117 | _HAssert( _Heap_Is_aligned( alloc_begin, alignment ) ); |
---|
118 | } |
---|
119 | |
---|
120 | if ( boundary != 0 ) { |
---|
121 | uintptr_t boundary_line = _Heap_Align_down( alloc_end, boundary ); |
---|
122 | |
---|
123 | _HAssert( alloc_size <= boundary ); |
---|
124 | _HAssert( boundary_line <= alloc_begin || alloc_end <= boundary_line ); |
---|
125 | } |
---|
126 | } |
---|
127 | #else |
---|
128 | #define _Heap_Check_allocation( h, b, ab, as, ag, bd ) ((void) 0) |
---|
129 | #endif |
---|
130 | |
---|
131 | static uintptr_t _Heap_Check_block( |
---|
132 | const Heap_Control *heap, |
---|
133 | const Heap_Block *block, |
---|
134 | uintptr_t alloc_size, |
---|
135 | uintptr_t alignment, |
---|
136 | uintptr_t boundary |
---|
137 | ) |
---|
138 | { |
---|
139 | uintptr_t const page_size = heap->page_size; |
---|
140 | uintptr_t const min_block_size = heap->min_block_size; |
---|
141 | |
---|
142 | uintptr_t const block_begin = (uintptr_t) block; |
---|
143 | uintptr_t const block_size = _Heap_Block_size( block ); |
---|
144 | uintptr_t const block_end = block_begin + block_size; |
---|
145 | |
---|
146 | uintptr_t const alloc_begin_floor = _Heap_Alloc_area_of_block( block ); |
---|
147 | uintptr_t const alloc_begin_ceiling = block_end - min_block_size |
---|
148 | + HEAP_BLOCK_HEADER_SIZE + page_size - 1; |
---|
149 | |
---|
150 | uintptr_t alloc_end = block_end + HEAP_ALLOC_BONUS; |
---|
151 | uintptr_t alloc_begin = alloc_end - alloc_size; |
---|
152 | |
---|
153 | alloc_begin = _Heap_Align_down( alloc_begin, alignment ); |
---|
154 | |
---|
155 | /* Ensure that the we have a valid new block at the end */ |
---|
156 | if ( alloc_begin > alloc_begin_ceiling ) { |
---|
157 | alloc_begin = _Heap_Align_down( alloc_begin_ceiling, alignment ); |
---|
158 | } |
---|
159 | |
---|
160 | alloc_end = alloc_begin + alloc_size; |
---|
161 | |
---|
162 | /* Ensure boundary constaint */ |
---|
163 | if ( boundary != 0 ) { |
---|
164 | uintptr_t const boundary_floor = alloc_begin_floor + alloc_size; |
---|
165 | uintptr_t boundary_line = _Heap_Align_down( alloc_end, boundary ); |
---|
166 | |
---|
167 | while ( alloc_begin < boundary_line && boundary_line < alloc_end ) { |
---|
168 | if ( boundary_line < boundary_floor ) { |
---|
169 | return 0; |
---|
170 | } |
---|
171 | alloc_begin = boundary_line - alloc_size; |
---|
172 | alloc_begin = _Heap_Align_down( alloc_begin, alignment ); |
---|
173 | alloc_end = alloc_begin + alloc_size; |
---|
174 | boundary_line = _Heap_Align_down( alloc_end, boundary ); |
---|
175 | } |
---|
176 | } |
---|
177 | |
---|
178 | /* Ensure that the we have a valid new block at the beginning */ |
---|
179 | if ( alloc_begin >= alloc_begin_floor ) { |
---|
180 | uintptr_t const alloc_block_begin = |
---|
181 | (uintptr_t) _Heap_Block_of_alloc_area( alloc_begin, page_size ); |
---|
182 | uintptr_t const free_size = alloc_block_begin - block_begin; |
---|
183 | |
---|
184 | if ( free_size >= min_block_size || free_size == 0 ) { |
---|
185 | return alloc_begin; |
---|
186 | } |
---|
187 | } |
---|
188 | |
---|
189 | return 0; |
---|
190 | } |
---|
191 | |
---|
192 | void *_Heap_Allocate_aligned_with_boundary( |
---|
193 | Heap_Control *heap, |
---|
194 | uintptr_t alloc_size, |
---|
195 | uintptr_t alignment, |
---|
196 | uintptr_t boundary |
---|
197 | ) |
---|
198 | { |
---|
199 | Heap_Statistics *const stats = &heap->stats; |
---|
200 | uintptr_t const block_size_floor = alloc_size + HEAP_BLOCK_HEADER_SIZE |
---|
201 | - HEAP_ALLOC_BONUS; |
---|
202 | uintptr_t const page_size = heap->page_size; |
---|
203 | Heap_Block *block = NULL; |
---|
204 | uintptr_t alloc_begin = 0; |
---|
205 | uint32_t search_count = 0; |
---|
206 | bool search_again = false; |
---|
207 | |
---|
208 | if ( block_size_floor < alloc_size ) { |
---|
209 | /* Integer overflow occured */ |
---|
210 | return NULL; |
---|
211 | } |
---|
212 | |
---|
213 | if ( boundary != 0 ) { |
---|
214 | if ( boundary < alloc_size ) { |
---|
215 | return NULL; |
---|
216 | } |
---|
217 | |
---|
218 | if ( alignment == 0 ) { |
---|
219 | alignment = page_size; |
---|
220 | } |
---|
221 | } |
---|
222 | |
---|
223 | do { |
---|
224 | Heap_Block *const free_list_tail = _Heap_Free_list_tail( heap ); |
---|
225 | |
---|
226 | block = _Heap_Free_list_first( heap ); |
---|
227 | while ( block != free_list_tail ) { |
---|
228 | _HAssert( _Heap_Is_prev_used( block ) ); |
---|
229 | |
---|
230 | _Heap_Protection_block_check( heap, block ); |
---|
231 | |
---|
232 | /* |
---|
233 | * The HEAP_PREV_BLOCK_USED flag is always set in the block size_and_flag |
---|
234 | * field. Thus the value is about one unit larger than the real block |
---|
235 | * size. The greater than operator takes this into account. |
---|
236 | */ |
---|
237 | if ( block->size_and_flag > block_size_floor ) { |
---|
238 | if ( alignment == 0 ) { |
---|
239 | alloc_begin = _Heap_Alloc_area_of_block( block ); |
---|
240 | } else { |
---|
241 | alloc_begin = _Heap_Check_block( |
---|
242 | heap, |
---|
243 | block, |
---|
244 | alloc_size, |
---|
245 | alignment, |
---|
246 | boundary |
---|
247 | ); |
---|
248 | } |
---|
249 | } |
---|
250 | |
---|
251 | /* Statistics */ |
---|
252 | ++search_count; |
---|
253 | |
---|
254 | if ( alloc_begin != 0 ) { |
---|
255 | break; |
---|
256 | } |
---|
257 | |
---|
258 | block = block->next; |
---|
259 | } |
---|
260 | |
---|
261 | search_again = _Heap_Protection_free_delayed_blocks( heap, alloc_begin ); |
---|
262 | } while ( search_again ); |
---|
263 | |
---|
264 | if ( alloc_begin != 0 ) { |
---|
265 | block = _Heap_Block_allocate( heap, block, alloc_begin, alloc_size ); |
---|
266 | |
---|
267 | _Heap_Check_allocation( |
---|
268 | heap, |
---|
269 | block, |
---|
270 | alloc_begin, |
---|
271 | alloc_size, |
---|
272 | alignment, |
---|
273 | boundary |
---|
274 | ); |
---|
275 | |
---|
276 | /* Statistics */ |
---|
277 | ++stats->allocs; |
---|
278 | stats->searches += search_count; |
---|
279 | stats->lifetime_allocated += _Heap_Block_size( block ); |
---|
280 | } else { |
---|
281 | /* Statistics */ |
---|
282 | ++stats->failed_allocs; |
---|
283 | } |
---|
284 | |
---|
285 | /* Statistics */ |
---|
286 | if ( stats->max_search < search_count ) { |
---|
287 | stats->max_search = search_count; |
---|
288 | } |
---|
289 | |
---|
290 | return (void *) alloc_begin; |
---|
291 | } |
---|