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 */
64 /** mmap segment info: base + length */
70 /** Align pool header so that pointers are naturally aligned. */
71 #define pool_aligned_header_bytes \
72 round_pow2 (sizeof (pool_header_t), sizeof (void *))
74 /** Get pool header from user pool pointer */
75 always_inline pool_header_t *
78 return vec_aligned_header (v, sizeof (pool_header_t), sizeof (void *));
81 extern void _pool_init_fixed (void **, u32, u32);
82 extern void fpool_free (void *);
84 /** initialize a fixed-size, preallocated pool */
85 #define pool_init_fixed(pool,max_elts) \
87 _pool_init_fixed((void **)&(pool),sizeof(pool[0]),max_elts); \
90 /** Validate a pool */
92 pool_validate (void *v)
94 pool_header_t *p = pool_header (v);
95 uword i, n_free_bitmap;
100 n_free_bitmap = clib_bitmap_count_set_bits (p->free_bitmap);
101 ASSERT (n_free_bitmap == vec_len (p->free_indices));
102 for (i = 0; i < vec_len (p->free_indices); i++)
103 ASSERT (clib_bitmap_get (p->free_bitmap, p->free_indices[i]) == 1);
107 pool_header_validate_index (void *v, uword index)
109 pool_header_t *p = pool_header (v);
112 vec_validate (p->free_bitmap, index / BITS (uword));
115 #define pool_validate_index(v,i) \
117 uword __pool_validate_index = (i); \
118 vec_validate_ha ((v), __pool_validate_index, \
119 pool_aligned_header_bytes, /* align */ 0); \
120 pool_header_validate_index ((v), __pool_validate_index); \
123 /** Number of active elements in a pool.
124 * @return Number of active elements in a pool
129 uword ret = vec_len (v);
131 ret -= vec_len (pool_header (v)->free_indices);
135 /** Number of elements in pool vector.
137 @note You probably want to call pool_elts() instead.
139 #define pool_len(p) vec_len(p)
141 /** Number of elements in pool vector (usable as an lvalue)
143 @note You probably don't want to use this macro.
145 #define _pool_len(p) _vec_len(p)
147 /** Memory usage of pool header. */
149 pool_header_bytes (void *v)
151 pool_header_t *p = pool_header (v);
156 return vec_bytes (p->free_bitmap) + vec_bytes (p->free_indices);
159 /** Memory usage of pool. */
160 #define pool_bytes(P) (vec_bytes (P) + pool_header_bytes (P))
162 /** Local variable naming macro. */
163 #define _pool_var(v) _pool_##v
165 /** Number of elements that can fit into pool with current allocation */
166 #define pool_max_len(P) vec_max_elts (P, pool_aligned_header_bytes)
168 /** Number of free elements in pool */
169 #define pool_free_elts(P) \
171 pool_header_t *_pool_var (p) = pool_header (P); \
175 n_free += vec_len (_pool_var (p)->free_indices); \
176 /* Fixed-size pools have max_elts set non-zero */ \
177 if (_pool_var (p)->max_elts == 0) \
178 n_free += pool_max_len (P) - vec_len (P); \
183 /** Allocate an object E from a pool P (general version).
185 First search free list. If nothing is free extend vector of objects.
187 #define _pool_get_aligned_internal_numa(P,E,A,Z,N) \
189 pool_header_t * _pool_var (p) = pool_header (P); \
190 uword _pool_var (l); \
192 STATIC_ASSERT(A==0 || ((A % sizeof(P[0]))==0) \
193 || ((sizeof(P[0]) % A) == 0), \
194 "Pool aligned alloc of incorrectly sized object"); \
197 _pool_var (l) = vec_len (_pool_var (p)->free_indices); \
199 if (_pool_var (l) > 0) \
201 /* Return free element from free list. */ \
202 uword _pool_var (i) = \
203 _pool_var (p)->free_indices[_pool_var (l) - 1]; \
204 (E) = (P) + _pool_var (i); \
205 _pool_var (p)->free_bitmap = \
206 clib_bitmap_andnoti_notrim (_pool_var (p)->free_bitmap, \
208 _vec_len (_pool_var (p)->free_indices) = _pool_var (l) - 1; \
209 CLIB_MEM_UNPOISON((E), sizeof((E)[0])); \
213 /* fixed-size, preallocated pools cannot expand */ \
214 if ((P) && _pool_var(p)->max_elts) \
216 clib_warning ("can't expand fixed-size pool"); \
217 os_out_of_memory(); \
219 /* Nothing on free list, make a new element and return it. */ \
220 P = _vec_resize_numa (P, \
221 /* length_increment */ 1, \
222 /* new size */ (vec_len (P) + 1) * sizeof (P[0]), \
223 pool_aligned_header_bytes, \
226 E = vec_end (P) - 1; \
229 memset(E, 0, sizeof(*E)); \
232 #define pool_get_aligned_zero_numa(P,E,A,Z,S) \
233 _pool_get_aligned_internal_numa(P,E,A,Z,S)
235 #define pool_get_aligned_numa(P,E,A,S) \
236 _pool_get_aligned_internal_numa(P,E,A,0/*zero*/,S)
238 #define pool_get_numa(P,E,S) \
239 _pool_get_aligned_internal_numa(P,E,0/*align*/,0/*zero*/,S)
241 #define _pool_get_aligned_internal(P,E,A,Z) \
242 _pool_get_aligned_internal_numa(P,E,A,Z,VEC_NUMA_UNSPECIFIED)
244 /** Allocate an object E from a pool P with alignment A */
245 #define pool_get_aligned(P,E,A) _pool_get_aligned_internal(P,E,A,0)
247 /** Allocate an object E from a pool P with alignment A and zero it */
248 #define pool_get_aligned_zero(P,E,A) _pool_get_aligned_internal(P,E,A,1)
250 /** Allocate an object E from a pool P (unspecified alignment). */
251 #define pool_get(P,E) pool_get_aligned(P,E,0)
253 /** Allocate an object E from a pool P and zero it */
254 #define pool_get_zero(P,E) pool_get_aligned_zero(P,E,0)
256 /** See if pool_get will expand the pool or not */
257 #define pool_get_aligned_will_expand(P,YESNO,A) \
259 pool_header_t * _pool_var (p) = pool_header (P); \
260 uword _pool_var (l); \
265 if (_pool_var (p)->max_elts) \
266 _pool_var (l) = _pool_var (p)->max_elts; \
268 _pool_var (l) = vec_len (_pool_var (p)->free_indices); \
271 /* Free elements, certainly won't expand */ \
272 if (_pool_var (l) > 0) \
276 /* Nothing on free list, make a new element and return it. */ \
277 YESNO = _vec_resize_will_expand \
279 /* length_increment */ 1, \
280 /* new size */ (vec_len (P) + 1) * sizeof (P[0]), \
281 pool_aligned_header_bytes, \
286 /** See if pool_put will expand free_bitmap or free_indices or not */
287 #define pool_put_will_expand(P, E, YESNO) \
290 pool_header_t *_pool_var (p) = pool_header (P); \
292 uword _pool_var (i) = (E) - (P); \
293 /* free_bitmap or free_indices may expand. */ \
295 clib_bitmap_will_expand (_pool_var (p)->free_bitmap, _pool_var (i)); \
297 YESNO += _vec_resize_will_expand ( \
298 _pool_var (p)->free_indices, 1, \
299 (vec_len (_pool_var (p)->free_indices) + 1) * \
300 sizeof (_pool_var (p)->free_indices[0]), \
305 /** Tell the caller if pool get will expand the pool */
306 #define pool_get_will_expand(P,YESNO) pool_get_aligned_will_expand(P,YESNO,0)
308 /** Use free bitmap to query whether given element is free. */
309 #define pool_is_free(P,E) \
311 pool_header_t * _pool_var (p) = pool_header (P); \
312 uword _pool_var (i) = (E) - (P); \
313 (_pool_var (i) < vec_len (P)) ? clib_bitmap_get (_pool_var (p)->free_bitmap, _pool_i) : 1; \
316 /** Use free bitmap to query whether given index is free */
317 #define pool_is_free_index(P,I) pool_is_free((P),(P)+(I))
319 /** Free an object E in pool P. */
320 #define pool_put(P, E) \
323 typeof (P) _pool_var (p__) = (P); \
324 typeof (E) _pool_var (e__) = (E); \
325 pool_header_t *_pool_var (p) = pool_header (_pool_var (p__)); \
326 uword _pool_var (l) = _pool_var (e__) - _pool_var (p__); \
327 if (_pool_var (p)->max_elts == 0) \
328 ASSERT (vec_is_member (_pool_var (p__), _pool_var (e__))); \
329 ASSERT (!pool_is_free (_pool_var (p__), _pool_var (e__))); \
331 /* Add element to free bitmap and to free list. */ \
332 _pool_var (p)->free_bitmap = \
333 clib_bitmap_ori_notrim (_pool_var (p)->free_bitmap, _pool_var (l)); \
335 /* Preallocated pool? */ \
336 if (_pool_var (p)->max_elts) \
338 ASSERT (_pool_var (l) < _pool_var (p)->max_elts); \
340 ->free_indices[_vec_len (_pool_var (p)->free_indices)] = \
342 _vec_len (_pool_var (p)->free_indices) += 1; \
345 vec_add1 (_pool_var (p)->free_indices, _pool_var (l)); \
347 CLIB_MEM_POISON (_pool_var (e__), sizeof (_pool_var (e__)[0])); \
351 /** Free pool element with given index. */
352 #define pool_put_index(p,i) \
354 typeof (p) _e = (p) + (i); \
358 /** Allocate N more free elements to pool (general version). */
359 #define pool_alloc_aligned(P,N,A) \
361 pool_header_t * _p; \
365 _p = pool_header (P); \
368 clib_warning ("Can't expand fixed-size pool"); \
369 os_out_of_memory(); \
373 (P) = _vec_resize ((P), 0, (vec_len (P) + (N)) * sizeof (P[0]), \
374 pool_aligned_header_bytes, \
376 _p = pool_header (P); \
377 vec_resize (_p->free_indices, (N)); \
378 _vec_len (_p->free_indices) -= (N); \
381 /** Allocate N more free elements to pool (unspecified alignment). */
382 #define pool_alloc(P,N) pool_alloc_aligned(P,N,0)
385 * Return copy of pool with alignment
387 * @param P pool to copy
388 * @param A alignment (may be zero)
389 * @return copy of pool
391 #define pool_dup_aligned(P, A) \
393 typeof (P) _pool_var (new) = 0; \
394 pool_header_t *_pool_var (ph), *_pool_var (new_ph); \
395 u32 _pool_var (n) = pool_len (P); \
398 _pool_var (new) = _vec_resize (_pool_var (new), _pool_var (n), \
399 _pool_var (n) * sizeof ((P)[0]), \
400 pool_aligned_header_bytes, (A)); \
401 CLIB_MEM_OVERFLOW_PUSH ((P), _pool_var (n) * sizeof ((P)[0])); \
402 clib_memcpy_fast (_pool_var (new), (P), \
403 _pool_var (n) * sizeof ((P)[0])); \
404 CLIB_MEM_OVERFLOW_POP (); \
405 _pool_var (ph) = pool_header (P); \
406 _pool_var (new_ph) = pool_header (_pool_var (new)); \
407 _pool_var (new_ph)->free_bitmap = \
408 clib_bitmap_dup (_pool_var (ph)->free_bitmap); \
409 _pool_var (new_ph)->free_indices = \
410 vec_dup (_pool_var (ph)->free_indices); \
411 _pool_var (new_ph)->max_elts = _pool_var (ph)->max_elts; \
417 * Return copy of pool without alignment
419 * @param P pool to copy
420 * @return copy of pool
422 #define pool_dup(P) pool_dup_aligned(P,0)
424 /** Low-level free pool operator (do not call directly). */
428 pool_header_t *p = pool_header (v);
431 clib_bitmap_free (p->free_bitmap);
437 rv = munmap (p->mmap_base, p->mmap_size);
439 clib_unix_warning ("munmap");
443 vec_free (p->free_indices);
444 vec_free_h (v, pool_aligned_header_bytes);
449 static_always_inline uword
450 pool_get_first_index (void *pool)
452 pool_header_t *h = pool_header (pool);
453 return clib_bitmap_first_clear (h->free_bitmap);
456 static_always_inline uword
457 pool_get_next_index (void *pool, uword last)
459 pool_header_t *h = pool_header (pool);
460 return clib_bitmap_next_clear (h->free_bitmap, last + 1);
464 #define pool_free(p) (p) = _pool_free(p)
466 /** Optimized iteration through pool.
468 @param LO pointer to first element in chunk
469 @param HI pointer to last element in chunk
470 @param POOL pool to iterate across
471 @param BODY operation to perform
473 Optimized version which assumes that BODY is smart enough to
474 process multiple (LOW,HI) chunks. See also pool_foreach().
476 #define pool_foreach_region(LO,HI,POOL,BODY) \
478 uword _pool_var (i), _pool_var (lo), _pool_var (hi), _pool_var (len); \
479 uword _pool_var (bl), * _pool_var (b); \
480 pool_header_t * _pool_var (p); \
482 _pool_var (p) = pool_header (POOL); \
483 _pool_var (b) = (POOL) ? _pool_var (p)->free_bitmap : 0; \
484 _pool_var (bl) = vec_len (_pool_var (b)); \
485 _pool_var (len) = vec_len (POOL); \
486 _pool_var (lo) = 0; \
488 for (_pool_var (i) = 0; \
489 _pool_var (i) <= _pool_var (bl); \
492 uword _pool_var (m), _pool_var (f); \
493 _pool_var (m) = (_pool_var (i) < _pool_var (bl) \
494 ? _pool_var (b) [_pool_var (i)] \
496 while (_pool_var (m) != 0) \
498 _pool_var (f) = first_set (_pool_var (m)); \
499 _pool_var (hi) = (_pool_var (i) * BITS (_pool_var (b)[0]) \
500 + min_log2 (_pool_var (f))); \
501 _pool_var (hi) = (_pool_var (i) < _pool_var (bl) \
502 ? _pool_var (hi) : _pool_var (len)); \
503 _pool_var (m) ^= _pool_var (f); \
504 if (_pool_var (hi) > _pool_var (lo)) \
506 (LO) = _pool_var (lo); \
507 (HI) = _pool_var (hi); \
508 do { BODY; } while (0); \
510 _pool_var (lo) = _pool_var (hi) + 1; \
515 /** Iterate through pool.
517 @param VAR A variable of same type as pool vector to be used as an
519 @param POOL The pool to iterate across.
520 @param BODY The operation to perform, typically a code block. See
523 This macro will call @c BODY with each active pool element.
525 It is a bad idea to allocate or free pool element from within
526 @c pool_foreach. Build a vector of indices and dispose of them later.
532 proc_t *procs; // a pool of processes.
533 proc_t *proc; // pointer to one process; used as the iterator.
535 pool_foreach (proc, procs, ({
536 if (proc->state != PROC_STATE_RUNNING)
539 // check a running proc in some way
544 @warning Because @c pool_foreach is a macro, syntax errors can be
545 difficult to find inside @c BODY, let alone actual code bugs. One
546 can temporarily split a complex @c pool_foreach into a trivial
547 @c pool_foreach which builds a vector of active indices, and a
548 vec_foreach() (or plain for-loop) to walk the active index vector.
551 #define pool_foreach(VAR,POOL) \
553 for (VAR = POOL + pool_get_first_index (POOL); \
554 VAR < vec_end (POOL); \
555 VAR = POOL + pool_get_next_index (POOL, VAR - POOL))
557 /** Returns pointer to element at given index.
559 ASSERTs that the supplied index is valid.
560 Even though one can write correct code of the form
562 p = pool_base + index;
564 use of @c pool_elt_at_index is strongly suggested.
566 #define pool_elt_at_index(p,i) \
568 typeof (p) _e = (p) + (i); \
569 ASSERT (! pool_is_free (p, _e)); \
573 /** Return next occupied pool index after @c i, useful for safe iteration. */
574 #define pool_next_index(P,I) \
576 pool_header_t * _pool_var (p) = pool_header (P); \
577 uword _pool_var (rv) = (I) + 1; \
580 (_pool_var (rv) < vec_len (P) ? \
581 clib_bitmap_next_clear (_pool_var (p)->free_bitmap, _pool_var(rv)) \
584 (_pool_var (rv) < vec_len (P) ? \
585 _pool_var (rv) : ~0); \
589 #define pool_foreach_index(i,v) \
591 for (i = pool_get_first_index (v); \
593 i = pool_get_next_index (v, i)) \
596 * @brief Remove all elements from a pool in a safe way
598 * @param VAR each element in the pool
599 * @param POOL The pool to flush
600 * @param BODY The actions to perform on each element before it is returned to
601 * the pool. i.e. before it is 'freed'
603 #define pool_flush(VAR, POOL, BODY) \
605 uword *_pool_var(ii), *_pool_var(dv) = NULL; \
607 pool_foreach((VAR), (POOL)) \
609 vec_add1(_pool_var(dv), (VAR) - (POOL)); \
611 vec_foreach(_pool_var(ii), _pool_var(dv)) \
613 (VAR) = pool_elt_at_index((POOL), *_pool_var(ii)); \
614 do { BODY; } while (0); \
615 pool_put((POOL), (VAR)); \
617 vec_free(_pool_var(dv)); \
620 #endif /* included_pool_h */
623 * fd.io coding-style-patch-verification: ON
626 * eval: (c-set-style "gnu")