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 bytes that can fit into pool with current allocation */
166 #define pool_capacity(P) vec_capacity (P, pool_aligned_header_bytes)
168 /** Number of elements that can fit into pool with current allocation */
169 #define pool_max_len(P) (pool_capacity (P) / sizeof (P[0]))
171 /** Number of free elements in pool */
172 #define pool_free_elts(P) \
174 pool_header_t *_pool_var (p) = pool_header (P); \
178 n_free += vec_len (_pool_var (p)->free_indices); \
179 /* Fixed-size pools have max_elts set non-zero */ \
180 if (_pool_var (p)->max_elts == 0) \
181 n_free += pool_max_len (P) - vec_len (P); \
186 /** Allocate an object E from a pool P (general version).
188 First search free list. If nothing is free extend vector of objects.
190 #define _pool_get_aligned_internal_numa(P,E,A,Z,N) \
192 pool_header_t * _pool_var (p) = pool_header (P); \
193 uword _pool_var (l); \
195 STATIC_ASSERT(A==0 || ((A % sizeof(P[0]))==0) \
196 || ((sizeof(P[0]) % A) == 0), \
197 "Pool aligned alloc of incorrectly sized object"); \
200 _pool_var (l) = vec_len (_pool_var (p)->free_indices); \
202 if (_pool_var (l) > 0) \
204 /* Return free element from free list. */ \
205 uword _pool_var (i) = \
206 _pool_var (p)->free_indices[_pool_var (l) - 1]; \
207 (E) = (P) + _pool_var (i); \
208 _pool_var (p)->free_bitmap = \
209 clib_bitmap_andnoti_notrim (_pool_var (p)->free_bitmap, \
211 _vec_len (_pool_var (p)->free_indices) = _pool_var (l) - 1; \
212 CLIB_MEM_UNPOISON((E), sizeof((E)[0])); \
216 /* fixed-size, preallocated pools cannot expand */ \
217 if ((P) && _pool_var(p)->max_elts) \
219 clib_warning ("can't expand fixed-size pool"); \
220 os_out_of_memory(); \
222 /* Nothing on free list, make a new element and return it. */ \
223 P = _vec_resize_numa (P, \
224 /* length_increment */ 1, \
225 /* new size */ (vec_len (P) + 1) * sizeof (P[0]), \
226 pool_aligned_header_bytes, \
229 E = vec_end (P) - 1; \
232 memset(E, 0, sizeof(*E)); \
235 #define pool_get_aligned_zero_numa(P,E,A,Z,S) \
236 _pool_get_aligned_internal_numa(P,E,A,Z,S)
238 #define pool_get_aligned_numa(P,E,A,S) \
239 _pool_get_aligned_internal_numa(P,E,A,0/*zero*/,S)
241 #define pool_get_numa(P,E,S) \
242 _pool_get_aligned_internal_numa(P,E,0/*align*/,0/*zero*/,S)
244 #define _pool_get_aligned_internal(P,E,A,Z) \
245 _pool_get_aligned_internal_numa(P,E,A,Z,VEC_NUMA_UNSPECIFIED)
247 /** Allocate an object E from a pool P with alignment A */
248 #define pool_get_aligned(P,E,A) _pool_get_aligned_internal(P,E,A,0)
250 /** Allocate an object E from a pool P with alignment A and zero it */
251 #define pool_get_aligned_zero(P,E,A) _pool_get_aligned_internal(P,E,A,1)
253 /** Allocate an object E from a pool P (unspecified alignment). */
254 #define pool_get(P,E) pool_get_aligned(P,E,0)
256 /** Allocate an object E from a pool P and zero it */
257 #define pool_get_zero(P,E) pool_get_aligned_zero(P,E,0)
259 /** See if pool_get will expand the pool or not */
260 #define pool_get_aligned_will_expand(P,YESNO,A) \
262 pool_header_t * _pool_var (p) = pool_header (P); \
263 uword _pool_var (l); \
268 if (_pool_var (p)->max_elts) \
269 _pool_var (l) = _pool_var (p)->max_elts; \
271 _pool_var (l) = vec_len (_pool_var (p)->free_indices); \
274 /* Free elements, certainly won't expand */ \
275 if (_pool_var (l) > 0) \
279 /* Nothing on free list, make a new element and return it. */ \
280 YESNO = _vec_resize_will_expand \
282 /* length_increment */ 1, \
283 /* new size */ (vec_len (P) + 1) * sizeof (P[0]), \
284 pool_aligned_header_bytes, \
289 /** See if pool_put will expand free_bitmap or free_indices or not */
290 #define pool_put_will_expand(P, E, YESNO) \
293 pool_header_t *_pool_var (p) = pool_header (P); \
295 uword _pool_var (i) = (E) - (P); \
296 /* free_bitmap or free_indices may expand. */ \
298 clib_bitmap_will_expand (_pool_var (p)->free_bitmap, _pool_var (i)); \
300 YESNO += _vec_resize_will_expand ( \
301 _pool_var (p)->free_indices, 1, \
302 (vec_len (_pool_var (p)->free_indices) + 1) * \
303 sizeof (_pool_var (p)->free_indices[0]), \
308 /** Tell the caller if pool get will expand the pool */
309 #define pool_get_will_expand(P,YESNO) pool_get_aligned_will_expand(P,YESNO,0)
311 /** Use free bitmap to query whether given element is free. */
312 #define pool_is_free(P,E) \
314 pool_header_t * _pool_var (p) = pool_header (P); \
315 uword _pool_var (i) = (E) - (P); \
316 (_pool_var (i) < vec_len (P)) ? clib_bitmap_get (_pool_var (p)->free_bitmap, _pool_i) : 1; \
319 /** Use free bitmap to query whether given index is free */
320 #define pool_is_free_index(P,I) pool_is_free((P),(P)+(I))
322 /** Free an object E in pool P. */
323 #define pool_put(P, E) \
326 typeof (P) _pool_var (p__) = (P); \
327 typeof (E) _pool_var (e__) = (E); \
328 pool_header_t *_pool_var (p) = pool_header (_pool_var (p__)); \
329 uword _pool_var (l) = _pool_var (e__) - _pool_var (p__); \
330 if (_pool_var (p)->max_elts == 0) \
331 ASSERT (vec_is_member (_pool_var (p__), _pool_var (e__))); \
332 ASSERT (!pool_is_free (_pool_var (p__), _pool_var (e__))); \
334 /* Add element to free bitmap and to free list. */ \
335 _pool_var (p)->free_bitmap = \
336 clib_bitmap_ori_notrim (_pool_var (p)->free_bitmap, _pool_var (l)); \
338 /* Preallocated pool? */ \
339 if (_pool_var (p)->max_elts) \
341 ASSERT (_pool_var (l) < _pool_var (p)->max_elts); \
343 ->free_indices[_vec_len (_pool_var (p)->free_indices)] = \
345 _vec_len (_pool_var (p)->free_indices) += 1; \
348 vec_add1 (_pool_var (p)->free_indices, _pool_var (l)); \
350 CLIB_MEM_POISON (_pool_var (e__), sizeof (_pool_var (e__)[0])); \
354 /** Free pool element with given index. */
355 #define pool_put_index(p,i) \
357 typeof (p) _e = (p) + (i); \
361 /** Allocate N more free elements to pool (general version). */
362 #define pool_alloc_aligned(P,N,A) \
364 pool_header_t * _p; \
368 _p = pool_header (P); \
371 clib_warning ("Can't expand fixed-size pool"); \
372 os_out_of_memory(); \
376 (P) = _vec_resize ((P), 0, (vec_len (P) + (N)) * sizeof (P[0]), \
377 pool_aligned_header_bytes, \
379 _p = pool_header (P); \
380 vec_resize (_p->free_indices, (N)); \
381 _vec_len (_p->free_indices) -= (N); \
384 /** Allocate N more free elements to pool (unspecified alignment). */
385 #define pool_alloc(P,N) pool_alloc_aligned(P,N,0)
388 * Return copy of pool with alignment
390 * @param P pool to copy
391 * @param A alignment (may be zero)
392 * @return copy of pool
394 #define pool_dup_aligned(P, A) \
396 typeof (P) _pool_var (new) = 0; \
397 pool_header_t *_pool_var (ph), *_pool_var (new_ph); \
398 u32 _pool_var (n) = pool_len (P); \
401 _pool_var (new) = _vec_resize (_pool_var (new), _pool_var (n), \
402 _pool_var (n) * sizeof ((P)[0]), \
403 pool_aligned_header_bytes, (A)); \
404 CLIB_MEM_OVERFLOW_PUSH ((P), _pool_var (n) * sizeof ((P)[0])); \
405 clib_memcpy_fast (_pool_var (new), (P), \
406 _pool_var (n) * sizeof ((P)[0])); \
407 CLIB_MEM_OVERFLOW_POP (); \
408 _pool_var (ph) = pool_header (P); \
409 _pool_var (new_ph) = pool_header (_pool_var (new)); \
410 _pool_var (new_ph)->free_bitmap = \
411 clib_bitmap_dup (_pool_var (ph)->free_bitmap); \
412 _pool_var (new_ph)->free_indices = \
413 vec_dup (_pool_var (ph)->free_indices); \
414 _pool_var (new_ph)->max_elts = _pool_var (ph)->max_elts; \
420 * Return copy of pool without alignment
422 * @param P pool to copy
423 * @return copy of pool
425 #define pool_dup(P) pool_dup_aligned(P,0)
427 /** Low-level free pool operator (do not call directly). */
431 pool_header_t *p = pool_header (v);
434 clib_bitmap_free (p->free_bitmap);
440 rv = munmap (p->mmap_base, p->mmap_size);
442 clib_unix_warning ("munmap");
446 vec_free (p->free_indices);
447 vec_free_h (v, pool_aligned_header_bytes);
452 static_always_inline uword
453 pool_get_first_index (void *pool)
455 pool_header_t *h = pool_header (pool);
456 return clib_bitmap_first_clear (h->free_bitmap);
459 static_always_inline uword
460 pool_get_next_index (void *pool, uword last)
462 pool_header_t *h = pool_header (pool);
463 return clib_bitmap_next_clear (h->free_bitmap, last + 1);
467 #define pool_free(p) (p) = _pool_free(p)
469 /** Optimized iteration through pool.
471 @param LO pointer to first element in chunk
472 @param HI pointer to last element in chunk
473 @param POOL pool to iterate across
474 @param BODY operation to perform
476 Optimized version which assumes that BODY is smart enough to
477 process multiple (LOW,HI) chunks. See also pool_foreach().
479 #define pool_foreach_region(LO,HI,POOL,BODY) \
481 uword _pool_var (i), _pool_var (lo), _pool_var (hi), _pool_var (len); \
482 uword _pool_var (bl), * _pool_var (b); \
483 pool_header_t * _pool_var (p); \
485 _pool_var (p) = pool_header (POOL); \
486 _pool_var (b) = (POOL) ? _pool_var (p)->free_bitmap : 0; \
487 _pool_var (bl) = vec_len (_pool_var (b)); \
488 _pool_var (len) = vec_len (POOL); \
489 _pool_var (lo) = 0; \
491 for (_pool_var (i) = 0; \
492 _pool_var (i) <= _pool_var (bl); \
495 uword _pool_var (m), _pool_var (f); \
496 _pool_var (m) = (_pool_var (i) < _pool_var (bl) \
497 ? _pool_var (b) [_pool_var (i)] \
499 while (_pool_var (m) != 0) \
501 _pool_var (f) = first_set (_pool_var (m)); \
502 _pool_var (hi) = (_pool_var (i) * BITS (_pool_var (b)[0]) \
503 + min_log2 (_pool_var (f))); \
504 _pool_var (hi) = (_pool_var (i) < _pool_var (bl) \
505 ? _pool_var (hi) : _pool_var (len)); \
506 _pool_var (m) ^= _pool_var (f); \
507 if (_pool_var (hi) > _pool_var (lo)) \
509 (LO) = _pool_var (lo); \
510 (HI) = _pool_var (hi); \
511 do { BODY; } while (0); \
513 _pool_var (lo) = _pool_var (hi) + 1; \
518 /** Iterate through pool.
520 @param VAR A variable of same type as pool vector to be used as an
522 @param POOL The pool to iterate across.
523 @param BODY The operation to perform, typically a code block. See
526 This macro will call @c BODY with each active pool element.
528 It is a bad idea to allocate or free pool element from within
529 @c pool_foreach. Build a vector of indices and dispose of them later.
535 proc_t *procs; // a pool of processes.
536 proc_t *proc; // pointer to one process; used as the iterator.
538 pool_foreach (proc, procs, ({
539 if (proc->state != PROC_STATE_RUNNING)
542 // check a running proc in some way
547 @warning Because @c pool_foreach is a macro, syntax errors can be
548 difficult to find inside @c BODY, let alone actual code bugs. One
549 can temporarily split a complex @c pool_foreach into a trivial
550 @c pool_foreach which builds a vector of active indices, and a
551 vec_foreach() (or plain for-loop) to walk the active index vector.
554 #define pool_foreach(VAR,POOL) \
556 for (VAR = POOL + pool_get_first_index (POOL); \
557 VAR < vec_end (POOL); \
558 VAR = POOL + pool_get_next_index (POOL, VAR - POOL))
560 /** Returns pointer to element at given index.
562 ASSERTs that the supplied index is valid.
563 Even though one can write correct code of the form
565 p = pool_base + index;
567 use of @c pool_elt_at_index is strongly suggested.
569 #define pool_elt_at_index(p,i) \
571 typeof (p) _e = (p) + (i); \
572 ASSERT (! pool_is_free (p, _e)); \
576 /** Return next occupied pool index after @c i, useful for safe iteration. */
577 #define pool_next_index(P,I) \
579 pool_header_t * _pool_var (p) = pool_header (P); \
580 uword _pool_var (rv) = (I) + 1; \
583 (_pool_var (rv) < vec_len (P) ? \
584 clib_bitmap_next_clear (_pool_var (p)->free_bitmap, _pool_var(rv)) \
587 (_pool_var (rv) < vec_len (P) ? \
588 _pool_var (rv) : ~0); \
592 #define pool_foreach_index(i,v) \
594 for (i = pool_get_first_index (v); \
596 i = pool_get_next_index (v, i)) \
599 * @brief Remove all elements from a pool in a safe way
601 * @param VAR each element in the pool
602 * @param POOL The pool to flush
603 * @param BODY The actions to perform on each element before it is returned to
604 * the pool. i.e. before it is 'freed'
606 #define pool_flush(VAR, POOL, BODY) \
608 uword *_pool_var(ii), *_pool_var(dv) = NULL; \
610 pool_foreach((VAR), (POOL)) \
612 vec_add1(_pool_var(dv), (VAR) - (POOL)); \
614 vec_foreach(_pool_var(ii), _pool_var(dv)) \
616 (VAR) = pool_elt_at_index((POOL), *_pool_var(ii)); \
617 do { BODY; } while (0); \
618 pool_put((POOL), (VAR)); \
620 vec_free(_pool_var(dv)); \
623 #endif /* included_pool_h */
626 * fd.io coding-style-patch-verification: ON
629 * eval: (c-set-style "gnu")