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 vec_aligned_header_bytes (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 /** Queries whether pool has at least N_FREE free elements. */
167 pool_free_elts (void *v)
169 pool_header_t *p = pool_header (v);
174 n_free += vec_len (p->free_indices);
177 * Space left at end of vector?
178 * Fixed-size pools have max_elts set non-zero,
180 if (p->max_elts == 0)
181 n_free += vec_capacity (v, sizeof (p[0])) - vec_len (v);
187 /** Allocate an object E from a pool P (general version).
189 First search free list. If nothing is free extend vector of objects.
191 #define _pool_get_aligned_internal_numa(P,E,A,Z,N) \
193 pool_header_t * _pool_var (p) = pool_header (P); \
194 uword _pool_var (l); \
196 STATIC_ASSERT(A==0 || ((A % sizeof(P[0]))==0) \
197 || ((sizeof(P[0]) % A) == 0), \
198 "Pool aligned alloc of incorrectly sized object"); \
201 _pool_var (l) = vec_len (_pool_var (p)->free_indices); \
203 if (_pool_var (l) > 0) \
205 /* Return free element from free list. */ \
206 uword _pool_var (i) = \
207 _pool_var (p)->free_indices[_pool_var (l) - 1]; \
208 (E) = (P) + _pool_var (i); \
209 _pool_var (p)->free_bitmap = \
210 clib_bitmap_andnoti_notrim (_pool_var (p)->free_bitmap, \
212 _vec_len (_pool_var (p)->free_indices) = _pool_var (l) - 1; \
213 CLIB_MEM_UNPOISON((E), sizeof((E)[0])); \
217 /* fixed-size, preallocated pools cannot expand */ \
218 if ((P) && _pool_var(p)->max_elts) \
220 clib_warning ("can't expand fixed-size pool"); \
221 os_out_of_memory(); \
223 /* Nothing on free list, make a new element and return it. */ \
224 P = _vec_resize_numa (P, \
225 /* length_increment */ 1, \
226 /* new size */ (vec_len (P) + 1) * sizeof (P[0]), \
227 pool_aligned_header_bytes, \
230 E = vec_end (P) - 1; \
233 memset(E, 0, sizeof(*E)); \
236 #define pool_get_aligned_zero_numa(P,E,A,Z,S) \
237 _pool_get_aligned_internal_numa(P,E,A,Z,S)
239 #define pool_get_aligned_numa(P,E,A,S) \
240 _pool_get_aligned_internal_numa(P,E,A,0/*zero*/,S)
242 #define pool_get_numa(P,E,S) \
243 _pool_get_aligned_internal_numa(P,E,0/*align*/,0/*zero*/,S)
245 #define _pool_get_aligned_internal(P,E,A,Z) \
246 _pool_get_aligned_internal_numa(P,E,A,Z,VEC_NUMA_UNSPECIFIED)
248 /** Allocate an object E from a pool P with alignment A */
249 #define pool_get_aligned(P,E,A) _pool_get_aligned_internal(P,E,A,0)
251 /** Allocate an object E from a pool P with alignment A and zero it */
252 #define pool_get_aligned_zero(P,E,A) _pool_get_aligned_internal(P,E,A,1)
254 /** Allocate an object E from a pool P (unspecified alignment). */
255 #define pool_get(P,E) pool_get_aligned(P,E,0)
257 /** Allocate an object E from a pool P and zero it */
258 #define pool_get_zero(P,E) pool_get_aligned_zero(P,E,0)
260 /** See if pool_get will expand the pool or not */
261 #define pool_get_aligned_will_expand(P,YESNO,A) \
263 pool_header_t * _pool_var (p) = pool_header (P); \
264 uword _pool_var (l); \
269 if (_pool_var (p)->max_elts) \
270 _pool_var (l) = _pool_var (p)->max_elts; \
272 _pool_var (l) = vec_len (_pool_var (p)->free_indices); \
275 /* Free elements, certainly won't expand */ \
276 if (_pool_var (l) > 0) \
280 /* Nothing on free list, make a new element and return it. */ \
281 YESNO = _vec_resize_will_expand \
283 /* length_increment */ 1, \
284 /* new size */ (vec_len (P) + 1) * sizeof (P[0]), \
285 pool_aligned_header_bytes, \
290 /** Tell the caller if pool get will expand the pool */
291 #define pool_get_will_expand(P,YESNO) pool_get_aligned_will_expand(P,YESNO,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_memcpy_fast (_pool_var (new), (P), \
387 _pool_var (n) * sizeof ((P)[0])); \
388 _pool_var (ph) = pool_header (P); \
389 _pool_var (new_ph) = pool_header (_pool_var (new)); \
390 _pool_var (new_ph)->free_bitmap = \
391 clib_bitmap_dup (_pool_var (ph)->free_bitmap); \
392 _pool_var (new_ph)->free_indices = \
393 vec_dup (_pool_var (ph)->free_indices); \
394 _pool_var (new_ph)->max_elts = _pool_var (ph)->max_elts; \
400 * Return copy of pool without alignment
402 * @param P pool to copy
403 * @return copy of pool
405 #define pool_dup(P) pool_dup_aligned(P,0)
407 /** Low-level free pool operator (do not call directly). */
411 pool_header_t *p = pool_header (v);
414 clib_bitmap_free (p->free_bitmap);
420 rv = munmap (p->mmap_base, p->mmap_size);
422 clib_unix_warning ("munmap");
426 vec_free (p->free_indices);
427 vec_free_h (v, pool_aligned_header_bytes);
432 static_always_inline uword
433 pool_get_first_index (void *pool)
435 pool_header_t *h = pool_header (pool);
436 return clib_bitmap_first_clear (h->free_bitmap);
439 static_always_inline uword
440 pool_get_next_index (void *pool, uword last)
442 pool_header_t *h = pool_header (pool);
443 return clib_bitmap_next_clear (h->free_bitmap, last + 1);
447 #define pool_free(p) (p) = _pool_free(p)
449 /** Optimized iteration through pool.
451 @param LO pointer to first element in chunk
452 @param HI pointer to last element in chunk
453 @param POOL pool to iterate across
454 @param BODY operation to perform
456 Optimized version which assumes that BODY is smart enough to
457 process multiple (LOW,HI) chunks. See also pool_foreach().
459 #define pool_foreach_region(LO,HI,POOL,BODY) \
461 uword _pool_var (i), _pool_var (lo), _pool_var (hi), _pool_var (len); \
462 uword _pool_var (bl), * _pool_var (b); \
463 pool_header_t * _pool_var (p); \
465 _pool_var (p) = pool_header (POOL); \
466 _pool_var (b) = (POOL) ? _pool_var (p)->free_bitmap : 0; \
467 _pool_var (bl) = vec_len (_pool_var (b)); \
468 _pool_var (len) = vec_len (POOL); \
469 _pool_var (lo) = 0; \
471 for (_pool_var (i) = 0; \
472 _pool_var (i) <= _pool_var (bl); \
475 uword _pool_var (m), _pool_var (f); \
476 _pool_var (m) = (_pool_var (i) < _pool_var (bl) \
477 ? _pool_var (b) [_pool_var (i)] \
479 while (_pool_var (m) != 0) \
481 _pool_var (f) = first_set (_pool_var (m)); \
482 _pool_var (hi) = (_pool_var (i) * BITS (_pool_var (b)[0]) \
483 + min_log2 (_pool_var (f))); \
484 _pool_var (hi) = (_pool_var (i) < _pool_var (bl) \
485 ? _pool_var (hi) : _pool_var (len)); \
486 _pool_var (m) ^= _pool_var (f); \
487 if (_pool_var (hi) > _pool_var (lo)) \
489 (LO) = _pool_var (lo); \
490 (HI) = _pool_var (hi); \
491 do { BODY; } while (0); \
493 _pool_var (lo) = _pool_var (hi) + 1; \
498 /** Iterate through pool.
500 @param VAR A variable of same type as pool vector to be used as an
502 @param POOL The pool to iterate across.
503 @param BODY The operation to perform, typically a code block. See
506 This macro will call @c BODY with each active pool element.
508 It is a bad idea to allocate or free pool element from within
509 @c pool_foreach. Build a vector of indices and dispose of them later.
515 proc_t *procs; // a pool of processes.
516 proc_t *proc; // pointer to one process; used as the iterator.
518 pool_foreach (proc, procs, ({
519 if (proc->state != PROC_STATE_RUNNING)
522 // check a running proc in some way
527 @warning Because @c pool_foreach is a macro, syntax errors can be
528 difficult to find inside @c BODY, let alone actual code bugs. One
529 can temporarily split a complex @c pool_foreach into a trivial
530 @c pool_foreach which builds a vector of active indices, and a
531 vec_foreach() (or plain for-loop) to walk the active index vector.
534 #define pool_foreach(VAR,POOL) \
536 for (VAR = POOL + pool_get_first_index (POOL); \
537 VAR < vec_end (POOL); \
538 VAR = POOL + pool_get_next_index (POOL, VAR - POOL))
540 /** Returns pointer to element at given index.
542 ASSERTs that the supplied index is valid.
543 Even though one can write correct code of the form
545 p = pool_base + index;
547 use of @c pool_elt_at_index is strongly suggested.
549 #define pool_elt_at_index(p,i) \
551 typeof (p) _e = (p) + (i); \
552 ASSERT (! pool_is_free (p, _e)); \
556 /** Return next occupied pool index after @c i, useful for safe iteration. */
557 #define pool_next_index(P,I) \
559 pool_header_t * _pool_var (p) = pool_header (P); \
560 uword _pool_var (rv) = (I) + 1; \
563 (_pool_var (rv) < vec_len (P) ? \
564 clib_bitmap_next_clear (_pool_var (p)->free_bitmap, _pool_var(rv)) \
567 (_pool_var (rv) < vec_len (P) ? \
568 _pool_var (rv) : ~0); \
572 #define pool_foreach_index(i,v) \
574 for (i = pool_get_first_index (v); \
576 i = pool_get_next_index (v, i)) \
579 * @brief Remove all elements from a pool in a safe way
581 * @param VAR each element in the pool
582 * @param POOL The pool to flush
583 * @param BODY The actions to perform on each element before it is returned to
584 * the pool. i.e. before it is 'freed'
586 #define pool_flush(VAR, POOL, BODY) \
588 uword *_pool_var(ii), *_pool_var(dv) = NULL; \
590 pool_foreach((VAR), (POOL)) \
592 vec_add1(_pool_var(dv), (VAR) - (POOL)); \
594 vec_foreach(_pool_var(ii), _pool_var(dv)) \
596 (VAR) = pool_elt_at_index((POOL), *_pool_var(ii)); \
597 do { BODY; } while (0); \
598 pool_put((POOL), (VAR)); \
600 vec_free(_pool_var(dv)); \
603 #endif /* included_pool_h */
606 * fd.io coding-style-patch-verification: ON
609 * eval: (c-set-style "gnu")