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);
176 /* Space left at end of vector? */
177 n_free += vec_capacity (v, sizeof (p[0])) - vec_len (v);
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 /** Tell the caller if pool get will expand the pool */
287 #define pool_get_will_expand(P,YESNO) pool_get_aligned_will_expand(P,YESNO,0)
289 /** Use free bitmap to query whether given element is free. */
290 #define pool_is_free(P,E) \
292 pool_header_t * _pool_var (p) = pool_header (P); \
293 uword _pool_var (i) = (E) - (P); \
294 (_pool_var (i) < vec_len (P)) ? clib_bitmap_get (_pool_var (p)->free_bitmap, _pool_i) : 1; \
297 /** Use free bitmap to query whether given index is free */
298 #define pool_is_free_index(P,I) pool_is_free((P),(P)+(I))
300 /** Free an object E in pool P. */
301 #define pool_put(P,E) \
303 typeof (P) _pool_var(p__) = (P); \
304 typeof (E) _pool_var(e__) = (E); \
305 pool_header_t * _pool_var (p) = pool_header (_pool_var(p__)); \
306 uword _pool_var (l) = _pool_var(e__) - _pool_var(p__); \
307 ASSERT (vec_is_member (_pool_var(p__), _pool_var(e__))); \
308 ASSERT (! pool_is_free (_pool_var(p__), _pool_var(e__))); \
310 /* Add element to free bitmap and to free list. */ \
311 _pool_var (p)->free_bitmap = \
312 clib_bitmap_ori_notrim (_pool_var (p)->free_bitmap, \
315 /* Preallocated pool? */ \
316 if (_pool_var (p)->max_elts) \
318 ASSERT(_pool_var(l) < _pool_var (p)->max_elts); \
319 _pool_var(p)->free_indices[_vec_len(_pool_var(p)->free_indices)] = \
321 _vec_len(_pool_var(p)->free_indices) += 1; \
324 vec_add1 (_pool_var (p)->free_indices, _pool_var (l)); \
326 CLIB_MEM_POISON(_pool_var(e__), sizeof(_pool_var(e__)[0])); \
329 /** Free pool element with given index. */
330 #define pool_put_index(p,i) \
332 typeof (p) _e = (p) + (i); \
336 /** Allocate N more free elements to pool (general version). */
337 #define pool_alloc_aligned(P,N,A) \
339 pool_header_t * _p; \
343 _p = pool_header (P); \
346 clib_warning ("Can't expand fixed-size pool"); \
347 os_out_of_memory(); \
351 (P) = _vec_resize ((P), 0, (vec_len (P) + (N)) * sizeof (P[0]), \
352 pool_aligned_header_bytes, \
354 _p = pool_header (P); \
355 vec_resize (_p->free_indices, (N)); \
356 _vec_len (_p->free_indices) -= (N); \
359 /** Allocate N more free elements to pool (unspecified alignment). */
360 #define pool_alloc(P,N) pool_alloc_aligned(P,N,0)
363 * Return copy of pool with alignment
365 * @param P pool to copy
366 * @param A alignment (may be zero)
367 * @return copy of pool
369 #define pool_dup_aligned(P,A) \
371 typeof (P) _pool_var (new) = 0; \
372 pool_header_t * _pool_var (ph), * _pool_var (new_ph); \
373 u32 _pool_var (n) = pool_len (P); \
376 _pool_var (new) = _vec_resize (_pool_var (new), _pool_var (n), \
377 _pool_var (n) * sizeof ((P)[0]), \
378 pool_aligned_header_bytes, (A)); \
379 clib_memcpy_fast (_pool_var (new), (P), \
380 _pool_var (n) * sizeof ((P)[0])); \
381 _pool_var (ph) = pool_header (P); \
382 _pool_var (new_ph) = pool_header (_pool_var (new)); \
383 _pool_var (new_ph)->free_bitmap = \
384 clib_bitmap_dup (_pool_var (ph)->free_bitmap); \
385 _pool_var (new_ph)->free_indices = \
386 vec_dup (_pool_var (ph)->free_indices); \
387 _pool_var (new_ph)->max_elts = _pool_var (ph)->max_elts; \
393 * Return copy of pool without alignment
395 * @param P pool to copy
396 * @return copy of pool
398 #define pool_dup(P) pool_dup_aligned(P,0)
400 /** Low-level free pool operator (do not call directly). */
404 pool_header_t *p = pool_header (v);
407 clib_bitmap_free (p->free_bitmap);
413 rv = munmap (p->mmap_base, p->mmap_size);
415 clib_unix_warning ("munmap");
419 vec_free (p->free_indices);
420 vec_free_h (v, pool_aligned_header_bytes);
425 static_always_inline uword
426 pool_get_first_index (void *pool)
428 pool_header_t *h = pool_header (pool);
429 return clib_bitmap_first_clear (h->free_bitmap);
432 static_always_inline uword
433 pool_get_next_index (void *pool, uword last)
435 pool_header_t *h = pool_header (pool);
436 return clib_bitmap_next_clear (h->free_bitmap, last + 1);
440 #define pool_free(p) (p) = _pool_free(p)
442 /** Optimized iteration through pool.
444 @param LO pointer to first element in chunk
445 @param HI pointer to last element in chunk
446 @param POOL pool to iterate across
447 @param BODY operation to perform
449 Optimized version which assumes that BODY is smart enough to
450 process multiple (LOW,HI) chunks. See also pool_foreach().
452 #define pool_foreach_region(LO,HI,POOL,BODY) \
454 uword _pool_var (i), _pool_var (lo), _pool_var (hi), _pool_var (len); \
455 uword _pool_var (bl), * _pool_var (b); \
456 pool_header_t * _pool_var (p); \
458 _pool_var (p) = pool_header (POOL); \
459 _pool_var (b) = (POOL) ? _pool_var (p)->free_bitmap : 0; \
460 _pool_var (bl) = vec_len (_pool_var (b)); \
461 _pool_var (len) = vec_len (POOL); \
462 _pool_var (lo) = 0; \
464 for (_pool_var (i) = 0; \
465 _pool_var (i) <= _pool_var (bl); \
468 uword _pool_var (m), _pool_var (f); \
469 _pool_var (m) = (_pool_var (i) < _pool_var (bl) \
470 ? _pool_var (b) [_pool_var (i)] \
472 while (_pool_var (m) != 0) \
474 _pool_var (f) = first_set (_pool_var (m)); \
475 _pool_var (hi) = (_pool_var (i) * BITS (_pool_var (b)[0]) \
476 + min_log2 (_pool_var (f))); \
477 _pool_var (hi) = (_pool_var (i) < _pool_var (bl) \
478 ? _pool_var (hi) : _pool_var (len)); \
479 _pool_var (m) ^= _pool_var (f); \
480 if (_pool_var (hi) > _pool_var (lo)) \
482 (LO) = _pool_var (lo); \
483 (HI) = _pool_var (hi); \
484 do { BODY; } while (0); \
486 _pool_var (lo) = _pool_var (hi) + 1; \
491 /** Iterate through pool.
493 @param VAR A variable of same type as pool vector to be used as an
495 @param POOL The pool to iterate across.
496 @param BODY The operation to perform, typically a code block. See
499 This macro will call @c BODY with each active pool element.
501 It is a bad idea to allocate or free pool element from within
502 @c pool_foreach. Build a vector of indices and dispose of them later.
508 proc_t *procs; // a pool of processes.
509 proc_t *proc; // pointer to one process; used as the iterator.
511 pool_foreach (proc, procs, ({
512 if (proc->state != PROC_STATE_RUNNING)
515 // check a running proc in some way
520 @warning Because @c pool_foreach is a macro, syntax errors can be
521 difficult to find inside @c BODY, let alone actual code bugs. One
522 can temporarily split a complex @c pool_foreach into a trivial
523 @c pool_foreach which builds a vector of active indices, and a
524 vec_foreach() (or plain for-loop) to walk the active index vector.
527 #define pool_foreach2(VAR,POOL) \
529 for (VAR = POOL + pool_get_first_index (POOL); \
530 VAR < vec_end (POOL); \
531 VAR = POOL + pool_get_next_index (POOL, VAR - POOL))
533 #define pool_foreach(VAR,POOL,BODY) \
534 pool_foreach2(VAR,POOL) \
537 /** Returns pointer to element at given index.
539 ASSERTs that the supplied index is valid.
540 Even though one can write correct code of the form
542 p = pool_base + index;
544 use of @c pool_elt_at_index is strongly suggested.
546 #define pool_elt_at_index(p,i) \
548 typeof (p) _e = (p) + (i); \
549 ASSERT (! pool_is_free (p, _e)); \
553 /** Return next occupied pool index after @c i, useful for safe iteration. */
554 #define pool_next_index(P,I) \
556 pool_header_t * _pool_var (p) = pool_header (P); \
557 uword _pool_var (rv) = (I) + 1; \
560 (_pool_var (rv) < vec_len (P) ? \
561 clib_bitmap_next_clear (_pool_var (p)->free_bitmap, _pool_var(rv)) \
564 (_pool_var (rv) < vec_len (P) ? \
565 _pool_var (rv) : ~0); \
569 #define pool_foreach_index2(i,v) \
571 for (i = pool_get_first_index (v); \
573 i = pool_get_next_index (v, i)) \
575 /** Iterate pool by index. */
576 #define pool_foreach_index(i,v,body) \
577 pool_foreach_index2 (i,v) \
581 * @brief Remove all elements from a pool in a safe way
583 * @param VAR each element in the pool
584 * @param POOL The pool to flush
585 * @param BODY The actions to perform on each element before it is returned to
586 * the pool. i.e. before it is 'freed'
588 #define pool_flush(VAR, POOL, BODY) \
590 uword *_pool_var(ii), *_pool_var(dv) = NULL; \
592 pool_foreach((VAR), (POOL), \
594 vec_add1(_pool_var(dv), (VAR) - (POOL)); \
596 vec_foreach(_pool_var(ii), _pool_var(dv)) \
598 (VAR) = pool_elt_at_index((POOL), *_pool_var(ii)); \
599 do { BODY; } while (0); \
600 pool_put((POOL), (VAR)); \
602 vec_free(_pool_var(dv)); \
605 #endif /* included_pool_h */
608 * fd.io coding-style-patch-verification: ON
611 * eval: (c-set-style "gnu")