2 * Copyright (c) 2015 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 Copyright (c) 2001, 2002, 2003, 2004 Eliot Dresselhaus
18 Permission is hereby granted, free of charge, to any person obtaining
19 a copy of this software and associated documentation files (the
20 "Software"), to deal in the Software without restriction, including
21 without limitation the rights to use, copy, modify, merge, publish,
22 distribute, sublicense, and/or sell copies of the Software, and to
23 permit persons to whom the Software is furnished to do so, subject to
24 the following conditions:
26 The above copyright notice and this permission notice shall be
27 included in all copies or substantial portions of the Software.
29 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
30 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
31 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
32 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
33 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
34 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
35 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
38 * @brief Fixed length block allocator.
39 Pools are built from clib vectors and bitmaps. Use pools when
40 repeatedly allocating and freeing fixed-size data. Pools are
41 fast, and avoid memory fragmentation.
44 #ifndef included_pool_h
45 #define included_pool_h
47 #include <vppinfra/bitmap.h>
48 #include <vppinfra/error.h>
53 /** Bitmap of indices of free objects. */
56 /** Vector of free indices. One element for each set bit in bitmap. */
59 /* The following fields are set for fixed-size, preallocated pools */
61 /** Maximum size of the pool, in elements */
66 /** Align pool header so that pointers are naturally aligned. */
67 #define pool_aligned_header_bytes \
68 round_pow2 (sizeof (pool_header_t), sizeof (void *))
70 /** Get pool header from user pool pointer */
71 always_inline pool_header_t *
74 return vec_header (v);
77 extern void _pool_init_fixed (void **, u32, u32);
78 extern void fpool_free (void *);
80 /** initialize a fixed-size, preallocated pool */
81 #define pool_init_fixed(pool,max_elts) \
83 _pool_init_fixed((void **)&(pool),sizeof(pool[0]),max_elts); \
86 /** Validate a pool */
88 pool_validate (void *v)
90 pool_header_t *p = pool_header (v);
91 uword i, n_free_bitmap;
96 n_free_bitmap = clib_bitmap_count_set_bits (p->free_bitmap);
97 ASSERT (n_free_bitmap == vec_len (p->free_indices));
98 for (i = 0; i < vec_len (p->free_indices); i++)
99 ASSERT (clib_bitmap_get (p->free_bitmap, p->free_indices[i]) == 1);
103 pool_header_validate_index (void *v, uword index)
105 pool_header_t *p = pool_header (v);
108 vec_validate (p->free_bitmap, index / BITS (uword));
111 #define pool_validate_index(v,i) \
113 uword __pool_validate_index = (i); \
114 vec_validate_ha ((v), __pool_validate_index, \
115 pool_aligned_header_bytes, /* align */ 0); \
116 pool_header_validate_index ((v), __pool_validate_index); \
119 /** Number of active elements in a pool.
120 * @return Number of active elements in a pool
125 uword ret = vec_len (v);
127 ret -= vec_len (pool_header (v)->free_indices);
131 /** Number of elements in pool vector.
133 @note You probably want to call pool_elts() instead.
135 #define pool_len(p) vec_len(p)
137 /** Number of elements in pool vector (usable as an lvalue)
139 @note You probably don't want to use this macro.
141 #define _pool_len(p) _vec_len(p)
143 /** Memory usage of pool header. */
145 pool_header_bytes (void *v)
147 pool_header_t *p = pool_header (v);
152 return vec_bytes (p->free_bitmap) + vec_bytes (p->free_indices);
155 /** Memory usage of pool. */
156 #define pool_bytes(P) (vec_bytes (P) + pool_header_bytes (P))
158 /** Local variable naming macro. */
159 #define _pool_var(v) _pool_##v
161 /** Number of elements that can fit into pool with current allocation */
162 #define pool_max_len(P) vec_max_len (P)
164 /** Number of free elements in pool */
165 #define pool_free_elts(P) \
167 pool_header_t *_pool_var (p) = pool_header (P); \
171 n_free += vec_len (_pool_var (p)->free_indices); \
172 /* Fixed-size pools have max_elts set non-zero */ \
173 if (_pool_var (p)->max_elts == 0) \
174 n_free += pool_max_len (P) - vec_len (P); \
179 /** Allocate an object E from a pool P (general version).
181 First search free list. If nothing is free extend vector of objects.
183 #define _pool_get_aligned_internal_numa(P,E,A,Z,N) \
185 pool_header_t * _pool_var (p) = pool_header (P); \
186 uword _pool_var (l); \
188 STATIC_ASSERT(A==0 || ((A % sizeof(P[0]))==0) \
189 || ((sizeof(P[0]) % A) == 0), \
190 "Pool aligned alloc of incorrectly sized object"); \
193 _pool_var (l) = vec_len (_pool_var (p)->free_indices); \
195 if (_pool_var (l) > 0) \
197 /* Return free element from free list. */ \
198 uword _pool_var (i) = \
199 _pool_var (p)->free_indices[_pool_var (l) - 1]; \
200 (E) = (P) + _pool_var (i); \
201 _pool_var (p)->free_bitmap = \
202 clib_bitmap_andnoti_notrim (_pool_var (p)->free_bitmap, \
204 _vec_len (_pool_var (p)->free_indices) = _pool_var (l) - 1; \
205 CLIB_MEM_UNPOISON((E), sizeof((E)[0])); \
209 /* fixed-size, preallocated pools cannot expand */ \
210 if ((P) && _pool_var(p)->max_elts) \
212 clib_warning ("can't expand fixed-size pool"); \
213 os_out_of_memory(); \
215 /* Nothing on free list, make a new element and return it. */ \
216 P = _vec_resize_numa (P, \
217 /* length_increment */ 1, \
218 /* new size */ (vec_len (P) + 1) * sizeof (P[0]), \
219 pool_aligned_header_bytes, \
222 E = vec_end (P) - 1; \
225 memset(E, 0, sizeof(*E)); \
228 #define pool_get_aligned_zero_numa(P,E,A,Z,S) \
229 _pool_get_aligned_internal_numa(P,E,A,Z,S)
231 #define pool_get_aligned_numa(P,E,A,S) \
232 _pool_get_aligned_internal_numa(P,E,A,0/*zero*/,S)
234 #define pool_get_numa(P,E,S) \
235 _pool_get_aligned_internal_numa(P,E,0/*align*/,0/*zero*/,S)
237 #define _pool_get_aligned_internal(P,E,A,Z) \
238 _pool_get_aligned_internal_numa(P,E,A,Z,VEC_NUMA_UNSPECIFIED)
240 /** Allocate an object E from a pool P with alignment A */
241 #define pool_get_aligned(P,E,A) _pool_get_aligned_internal(P,E,A,0)
243 /** Allocate an object E from a pool P with alignment A and zero it */
244 #define pool_get_aligned_zero(P,E,A) _pool_get_aligned_internal(P,E,A,1)
246 /** Allocate an object E from a pool P (unspecified alignment). */
247 #define pool_get(P,E) pool_get_aligned(P,E,0)
249 /** Allocate an object E from a pool P and zero it */
250 #define pool_get_zero(P,E) pool_get_aligned_zero(P,E,0)
253 _pool_get_will_expand (void *p, uword elt_size)
261 ph = pool_header (p);
266 len = vec_len (ph->free_indices);
268 /* Free elements, certainly won't expand */
272 return _vec_resize_will_expand (p, 1, elt_size);
275 #define pool_get_will_expand(P) _pool_get_will_expand (P, sizeof ((P)[0]))
278 _pool_put_will_expand (void *p, uword index, uword elt_size)
280 pool_header_t *ph = pool_header (p);
282 if (clib_bitmap_will_expand (ph->free_bitmap, index))
285 if (vec_resize_will_expand (ph->free_indices, 1))
291 #define pool_put_will_expand(P, E) _pool_put_will_expand (P, (E) - (P), sizeof ((P)[0])
293 /** Use free bitmap to query whether given element is free. */
294 #define pool_is_free(P,E) \
296 pool_header_t * _pool_var (p) = pool_header (P); \
297 uword _pool_var (i) = (E) - (P); \
298 (_pool_var (i) < vec_len (P)) ? clib_bitmap_get (_pool_var (p)->free_bitmap, _pool_i) : 1; \
301 /** Use free bitmap to query whether given index is free */
302 #define pool_is_free_index(P,I) pool_is_free((P),(P)+(I))
304 /** Free an object E in pool P. */
305 #define pool_put(P, E) \
308 typeof (P) _pool_var (p__) = (P); \
309 typeof (E) _pool_var (e__) = (E); \
310 pool_header_t *_pool_var (p) = pool_header (_pool_var (p__)); \
311 uword _pool_var (l) = _pool_var (e__) - _pool_var (p__); \
312 if (_pool_var (p)->max_elts == 0) \
313 ASSERT (vec_is_member (_pool_var (p__), _pool_var (e__))); \
314 ASSERT (!pool_is_free (_pool_var (p__), _pool_var (e__))); \
316 /* Add element to free bitmap and to free list. */ \
317 _pool_var (p)->free_bitmap = \
318 clib_bitmap_ori_notrim (_pool_var (p)->free_bitmap, _pool_var (l)); \
320 /* Preallocated pool? */ \
321 if (_pool_var (p)->max_elts) \
323 ASSERT (_pool_var (l) < _pool_var (p)->max_elts); \
325 ->free_indices[_vec_len (_pool_var (p)->free_indices)] = \
327 _vec_len (_pool_var (p)->free_indices) += 1; \
330 vec_add1 (_pool_var (p)->free_indices, _pool_var (l)); \
332 CLIB_MEM_POISON (_pool_var (e__), sizeof (_pool_var (e__)[0])); \
336 /** Free pool element with given index. */
337 #define pool_put_index(p,i) \
339 typeof (p) _e = (p) + (i); \
343 /** Allocate N more free elements to pool (general version). */
344 #define pool_alloc_aligned(P,N,A) \
346 pool_header_t * _p; \
350 _p = pool_header (P); \
353 clib_warning ("Can't expand fixed-size pool"); \
354 os_out_of_memory(); \
358 (P) = _vec_resize ((P), 0, (vec_len (P) + (N)) * sizeof (P[0]), \
359 pool_aligned_header_bytes, \
361 _p = pool_header (P); \
362 vec_resize (_p->free_indices, (N)); \
363 _vec_len (_p->free_indices) -= (N); \
366 /** Allocate N more free elements to pool (unspecified alignment). */
367 #define pool_alloc(P,N) pool_alloc_aligned(P,N,0)
370 * Return copy of pool with alignment
372 * @param P pool to copy
373 * @param A alignment (may be zero)
374 * @return copy of pool
376 #define pool_dup_aligned(P, A) \
378 typeof (P) _pool_var (new) = 0; \
379 pool_header_t *_pool_var (ph), *_pool_var (new_ph); \
380 u32 _pool_var (n) = pool_len (P); \
383 _pool_var (new) = _vec_resize (_pool_var (new), _pool_var (n), \
384 _pool_var (n) * sizeof ((P)[0]), \
385 pool_aligned_header_bytes, (A)); \
386 CLIB_MEM_OVERFLOW_PUSH ((P), _pool_var (n) * sizeof ((P)[0])); \
387 clib_memcpy_fast (_pool_var (new), (P), \
388 _pool_var (n) * sizeof ((P)[0])); \
389 CLIB_MEM_OVERFLOW_POP (); \
390 _pool_var (ph) = pool_header (P); \
391 _pool_var (new_ph) = pool_header (_pool_var (new)); \
392 _pool_var (new_ph)->free_bitmap = \
393 clib_bitmap_dup (_pool_var (ph)->free_bitmap); \
394 _pool_var (new_ph)->free_indices = \
395 vec_dup (_pool_var (ph)->free_indices); \
396 _pool_var (new_ph)->max_elts = _pool_var (ph)->max_elts; \
402 * Return copy of pool without alignment
404 * @param P pool to copy
405 * @return copy of pool
407 #define pool_dup(P) pool_dup_aligned(P,0)
409 /** Low-level free pool operator (do not call directly). */
413 pool_header_t *p = pool_header (v);
416 clib_bitmap_free (p->free_bitmap);
418 vec_free (p->free_indices);
423 static_always_inline uword
424 pool_get_first_index (void *pool)
426 pool_header_t *h = pool_header (pool);
427 return clib_bitmap_first_clear (h->free_bitmap);
430 static_always_inline uword
431 pool_get_next_index (void *pool, uword last)
433 pool_header_t *h = pool_header (pool);
434 return clib_bitmap_next_clear (h->free_bitmap, last + 1);
438 #define pool_free(p) (p) = _pool_free(p)
440 /** Optimized iteration through pool.
442 @param LO pointer to first element in chunk
443 @param HI pointer to last element in chunk
444 @param POOL pool to iterate across
445 @param BODY operation to perform
447 Optimized version which assumes that BODY is smart enough to
448 process multiple (LOW,HI) chunks. See also pool_foreach().
450 #define pool_foreach_region(LO,HI,POOL,BODY) \
452 uword _pool_var (i), _pool_var (lo), _pool_var (hi), _pool_var (len); \
453 uword _pool_var (bl), * _pool_var (b); \
454 pool_header_t * _pool_var (p); \
456 _pool_var (p) = pool_header (POOL); \
457 _pool_var (b) = (POOL) ? _pool_var (p)->free_bitmap : 0; \
458 _pool_var (bl) = vec_len (_pool_var (b)); \
459 _pool_var (len) = vec_len (POOL); \
460 _pool_var (lo) = 0; \
462 for (_pool_var (i) = 0; \
463 _pool_var (i) <= _pool_var (bl); \
466 uword _pool_var (m), _pool_var (f); \
467 _pool_var (m) = (_pool_var (i) < _pool_var (bl) \
468 ? _pool_var (b) [_pool_var (i)] \
470 while (_pool_var (m) != 0) \
472 _pool_var (f) = first_set (_pool_var (m)); \
473 _pool_var (hi) = (_pool_var (i) * BITS (_pool_var (b)[0]) \
474 + min_log2 (_pool_var (f))); \
475 _pool_var (hi) = (_pool_var (i) < _pool_var (bl) \
476 ? _pool_var (hi) : _pool_var (len)); \
477 _pool_var (m) ^= _pool_var (f); \
478 if (_pool_var (hi) > _pool_var (lo)) \
480 (LO) = _pool_var (lo); \
481 (HI) = _pool_var (hi); \
482 do { BODY; } while (0); \
484 _pool_var (lo) = _pool_var (hi) + 1; \
489 /** Iterate through pool.
491 @param VAR A variable of same type as pool vector to be used as an
493 @param POOL The pool to iterate across.
494 @param BODY The operation to perform, typically a code block. See
497 This macro will call @c BODY with each active pool element.
499 It is a bad idea to allocate or free pool element from within
500 @c pool_foreach. Build a vector of indices and dispose of them later.
506 proc_t *procs; // a pool of processes.
507 proc_t *proc; // pointer to one process; used as the iterator.
509 pool_foreach (proc, procs, ({
510 if (proc->state != PROC_STATE_RUNNING)
513 // check a running proc in some way
518 @warning Because @c pool_foreach is a macro, syntax errors can be
519 difficult to find inside @c BODY, let alone actual code bugs. One
520 can temporarily split a complex @c pool_foreach into a trivial
521 @c pool_foreach which builds a vector of active indices, and a
522 vec_foreach() (or plain for-loop) to walk the active index vector.
525 #define pool_foreach(VAR,POOL) \
527 for (VAR = POOL + pool_get_first_index (POOL); \
528 VAR < vec_end (POOL); \
529 VAR = POOL + pool_get_next_index (POOL, VAR - POOL))
531 /** Returns pointer to element at given index.
533 ASSERTs that the supplied index is valid.
534 Even though one can write correct code of the form
536 p = pool_base + index;
538 use of @c pool_elt_at_index is strongly suggested.
540 #define pool_elt_at_index(p,i) \
542 typeof (p) _e = (p) + (i); \
543 ASSERT (! pool_is_free (p, _e)); \
547 /** Return next occupied pool index after @c i, useful for safe iteration. */
548 #define pool_next_index(P,I) \
550 pool_header_t * _pool_var (p) = pool_header (P); \
551 uword _pool_var (rv) = (I) + 1; \
554 (_pool_var (rv) < vec_len (P) ? \
555 clib_bitmap_next_clear (_pool_var (p)->free_bitmap, _pool_var(rv)) \
558 (_pool_var (rv) < vec_len (P) ? \
559 _pool_var (rv) : ~0); \
563 #define pool_foreach_index(i,v) \
565 for (i = pool_get_first_index (v); \
567 i = pool_get_next_index (v, i)) \
570 * @brief Remove all elements from a pool in a safe way
572 * @param VAR each element in the pool
573 * @param POOL The pool to flush
574 * @param BODY The actions to perform on each element before it is returned to
575 * the pool. i.e. before it is 'freed'
577 #define pool_flush(VAR, POOL, BODY) \
579 uword *_pool_var(ii), *_pool_var(dv) = NULL; \
581 pool_foreach((VAR), (POOL)) \
583 vec_add1(_pool_var(dv), (VAR) - (POOL)); \
585 vec_foreach(_pool_var(ii), _pool_var(dv)) \
587 (VAR) = pool_elt_at_index((POOL), *_pool_var(ii)); \
588 do { BODY; } while (0); \
589 pool_put((POOL), (VAR)); \
591 vec_free(_pool_var(dv)); \
594 #endif /* included_pool_h */
597 * fd.io coding-style-patch-verification: ON
600 * eval: (c-set-style "gnu")