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>
49 #include <vppinfra/mheap.h>
54 /** Bitmap of indices of free objects. */
57 /** Vector of free indices. One element for each set bit in bitmap. */
60 /* The following fields are set for fixed-size, preallocated pools */
62 /** Maximum size of the pool, in elements */
65 /** mmap segment info: base + length */
71 /** Align pool header so that pointers are naturally aligned. */
72 #define pool_aligned_header_bytes \
73 vec_aligned_header_bytes (sizeof (pool_header_t), sizeof (void *))
75 /** Get pool header from user pool pointer */
76 always_inline pool_header_t *
79 return vec_aligned_header (v, sizeof (pool_header_t), sizeof (void *));
82 extern void _pool_init_fixed (void **, u32, u32);
83 extern void fpool_free (void *);
85 /** initialize a fixed-size, preallocated pool */
86 #define pool_init_fixed(pool,max_elts) \
88 _pool_init_fixed((void **)&(pool),sizeof(pool[0]),max_elts); \
91 /** Validate a pool */
93 pool_validate (void *v)
95 pool_header_t *p = pool_header (v);
96 uword i, n_free_bitmap;
101 n_free_bitmap = clib_bitmap_count_set_bits (p->free_bitmap);
102 ASSERT (n_free_bitmap == vec_len (p->free_indices));
103 for (i = 0; i < vec_len (p->free_indices); i++)
104 ASSERT (clib_bitmap_get (p->free_bitmap, p->free_indices[i]) == 1);
108 pool_header_validate_index (void *v, uword index)
110 pool_header_t *p = pool_header (v);
113 vec_validate (p->free_bitmap, index / BITS (uword));
116 #define pool_validate_index(v,i) \
118 uword __pool_validate_index = (i); \
119 vec_validate_ha ((v), __pool_validate_index, \
120 pool_aligned_header_bytes, /* align */ 0); \
121 pool_header_validate_index ((v), __pool_validate_index); \
124 /** Number of active elements in a pool.
125 * @return Number of active elements in a pool
130 uword ret = vec_len (v);
132 ret -= vec_len (pool_header (v)->free_indices);
136 /** Number of elements in pool vector.
138 @note You probably want to call pool_elts() instead.
140 #define pool_len(p) vec_len(p)
142 /** Number of elements in pool vector (usable as an lvalue)
144 @note You probably don't want to use this macro.
146 #define _pool_len(p) _vec_len(p)
148 /** Memory usage of pool header. */
150 pool_header_bytes (void *v)
152 pool_header_t *p = pool_header (v);
157 return vec_bytes (p->free_bitmap) + vec_bytes (p->free_indices);
160 /** Memory usage of pool. */
161 #define pool_bytes(P) (vec_bytes (P) + pool_header_bytes (P))
163 /** Local variable naming macro. */
164 #define _pool_var(v) _pool_##v
166 /** Queries whether pool has at least N_FREE free elements. */
168 pool_free_elts (void *v)
170 pool_header_t *p = pool_header (v);
175 n_free += vec_len (p->free_indices);
177 /* Space left at end of vector? */
178 n_free += vec_capacity (v, sizeof (p[0])) - vec_len (v);
184 /** Allocate an object E from a pool P (general version).
186 First search free list. If nothing is free extend vector of objects.
188 #define _pool_get_aligned_internal_numa(P,E,A,Z,N) \
190 pool_header_t * _pool_var (p) = pool_header (P); \
191 uword _pool_var (l); \
193 STATIC_ASSERT(A==0 || ((A % sizeof(P[0]))==0) \
194 || ((sizeof(P[0]) % A) == 0), \
195 "Pool aligned alloc of incorrectly sized object"); \
198 _pool_var (l) = vec_len (_pool_var (p)->free_indices); \
200 if (_pool_var (l) > 0) \
202 /* Return free element from free list. */ \
203 uword _pool_var (i) = \
204 _pool_var (p)->free_indices[_pool_var (l) - 1]; \
205 (E) = (P) + _pool_var (i); \
206 _pool_var (p)->free_bitmap = \
207 clib_bitmap_andnoti_notrim (_pool_var (p)->free_bitmap, \
209 _vec_len (_pool_var (p)->free_indices) = _pool_var (l) - 1; \
210 CLIB_MEM_UNPOISON((E), sizeof((E)[0])); \
214 /* fixed-size, preallocated pools cannot expand */ \
215 if ((P) && _pool_var(p)->max_elts) \
217 clib_warning ("can't expand fixed-size pool"); \
218 os_out_of_memory(); \
220 /* Nothing on free list, make a new element and return it. */ \
221 P = _vec_resize_numa (P, \
222 /* length_increment */ 1, \
223 /* new size */ (vec_len (P) + 1) * sizeof (P[0]), \
224 pool_aligned_header_bytes, \
227 E = vec_end (P) - 1; \
230 memset(E, 0, sizeof(*E)); \
233 #define pool_get_aligned_zero_numa(P,E,A,Z,S) \
234 _pool_get_aligned_internal_numa(P,E,A,Z,S)
236 #define pool_get_aligned_numa(P,E,A,S) \
237 _pool_get_aligned_internal_numa(P,E,A,0/*zero*/,S)
239 #define pool_get_numa(P,E,S) \
240 _pool_get_aligned_internal_numa(P,E,0/*align*/,0/*zero*/,S)
242 #define _pool_get_aligned_internal(P,E,A,Z) \
243 _pool_get_aligned_internal_numa(P,E,A,Z,VEC_NUMA_UNSPECIFIED)
245 /** Allocate an object E from a pool P with alignment A */
246 #define pool_get_aligned(P,E,A) _pool_get_aligned_internal(P,E,A,0)
248 /** Allocate an object E from a pool P with alignment A and zero it */
249 #define pool_get_aligned_zero(P,E,A) _pool_get_aligned_internal(P,E,A,1)
251 /** Allocate an object E from a pool P (unspecified alignment). */
252 #define pool_get(P,E) pool_get_aligned(P,E,0)
254 /** Allocate an object E from a pool P and zero it */
255 #define pool_get_zero(P,E) pool_get_aligned_zero(P,E,0)
257 /** See if pool_get will expand the pool or not */
258 #define pool_get_aligned_will_expand(P,YESNO,A) \
260 pool_header_t * _pool_var (p) = pool_header (P); \
261 uword _pool_var (l); \
266 if (_pool_var (p)->max_elts) \
267 _pool_var (l) = _pool_var (p)->max_elts; \
269 _pool_var (l) = vec_len (_pool_var (p)->free_indices); \
272 /* Free elements, certainly won't expand */ \
273 if (_pool_var (l) > 0) \
277 /* Nothing on free list, make a new element and return it. */ \
278 YESNO = _vec_resize_will_expand \
280 /* length_increment */ 1, \
281 /* new size */ (vec_len (P) + 1) * sizeof (P[0]), \
282 pool_aligned_header_bytes, \
287 /** Tell the caller if pool get will expand the pool */
288 #define pool_get_will_expand(P,YESNO) pool_get_aligned_will_expand(P,YESNO,0)
290 /** Use free bitmap to query whether given element is free. */
291 #define pool_is_free(P,E) \
293 pool_header_t * _pool_var (p) = pool_header (P); \
294 uword _pool_var (i) = (E) - (P); \
295 (_pool_var (i) < vec_len (P)) ? clib_bitmap_get (_pool_var (p)->free_bitmap, _pool_i) : 1; \
298 /** Use free bitmap to query whether given index is free */
299 #define pool_is_free_index(P,I) pool_is_free((P),(P)+(I))
301 /** Free an object E in pool P. */
302 #define pool_put(P,E) \
304 typeof (P) _pool_var(p__) = (P); \
305 typeof (E) _pool_var(e__) = (E); \
306 pool_header_t * _pool_var (p) = pool_header (_pool_var(p__)); \
307 uword _pool_var (l) = _pool_var(e__) - _pool_var(p__); \
308 ASSERT (vec_is_member (_pool_var(p__), _pool_var(e__))); \
309 ASSERT (! pool_is_free (_pool_var(p__), _pool_var(e__))); \
311 /* Add element to free bitmap and to free list. */ \
312 _pool_var (p)->free_bitmap = \
313 clib_bitmap_ori_notrim (_pool_var (p)->free_bitmap, \
316 /* Preallocated pool? */ \
317 if (_pool_var (p)->max_elts) \
319 ASSERT(_pool_var(l) < _pool_var (p)->max_elts); \
320 _pool_var(p)->free_indices[_vec_len(_pool_var(p)->free_indices)] = \
322 _vec_len(_pool_var(p)->free_indices) += 1; \
325 vec_add1 (_pool_var (p)->free_indices, _pool_var (l)); \
327 CLIB_MEM_POISON(_pool_var(e__), sizeof(_pool_var(e__)[0])); \
330 /** Free pool element with given index. */
331 #define pool_put_index(p,i) \
333 typeof (p) _e = (p) + (i); \
337 /** Allocate N more free elements to pool (general version). */
338 #define pool_alloc_aligned(P,N,A) \
340 pool_header_t * _p; \
344 _p = pool_header (P); \
347 clib_warning ("Can't expand fixed-size pool"); \
348 os_out_of_memory(); \
352 (P) = _vec_resize ((P), 0, (vec_len (P) + (N)) * sizeof (P[0]), \
353 pool_aligned_header_bytes, \
355 _p = pool_header (P); \
356 vec_resize (_p->free_indices, (N)); \
357 _vec_len (_p->free_indices) -= (N); \
360 /** Allocate N more free elements to pool (unspecified alignment). */
361 #define pool_alloc(P,N) pool_alloc_aligned(P,N,0)
364 * Return copy of pool with alignment
366 * @param P pool to copy
367 * @param A alignment (may be zero)
368 * @return copy of pool
370 #define pool_dup_aligned(P,A) \
372 typeof (P) _pool_var (new) = 0; \
373 pool_header_t * _pool_var (ph), * _pool_var (new_ph); \
374 u32 _pool_var (n) = pool_len (P); \
377 _pool_var (new) = _vec_resize (_pool_var (new), _pool_var (n), \
378 _pool_var (n) * sizeof ((P)[0]), \
379 pool_aligned_header_bytes, (A)); \
380 clib_memcpy_fast (_pool_var (new), (P), \
381 _pool_var (n) * sizeof ((P)[0])); \
382 _pool_var (ph) = pool_header (P); \
383 _pool_var (new_ph) = pool_header (_pool_var (new)); \
384 _pool_var (new_ph)->free_bitmap = \
385 clib_bitmap_dup (_pool_var (ph)->free_bitmap); \
386 _pool_var (new_ph)->free_indices = \
387 vec_dup (_pool_var (ph)->free_indices); \
388 _pool_var (new_ph)->max_elts = _pool_var (ph)->max_elts; \
394 * Return copy of pool without alignment
396 * @param P pool to copy
397 * @return copy of pool
399 #define pool_dup(P) pool_dup_aligned(P,0)
401 /** Low-level free pool operator (do not call directly). */
405 pool_header_t *p = pool_header (v);
408 clib_bitmap_free (p->free_bitmap);
414 rv = munmap (p->mmap_base, p->mmap_size);
416 clib_unix_warning ("munmap");
420 vec_free (p->free_indices);
421 vec_free_h (v, pool_aligned_header_bytes);
427 #define pool_free(p) (p) = _pool_free(p)
429 /** Optimized iteration through pool.
431 @param LO pointer to first element in chunk
432 @param HI pointer to last element in chunk
433 @param POOL pool to iterate across
434 @param BODY operation to perform
436 Optimized version which assumes that BODY is smart enough to
437 process multiple (LOW,HI) chunks. See also pool_foreach().
439 #define pool_foreach_region(LO,HI,POOL,BODY) \
441 uword _pool_var (i), _pool_var (lo), _pool_var (hi), _pool_var (len); \
442 uword _pool_var (bl), * _pool_var (b); \
443 pool_header_t * _pool_var (p); \
445 _pool_var (p) = pool_header (POOL); \
446 _pool_var (b) = (POOL) ? _pool_var (p)->free_bitmap : 0; \
447 _pool_var (bl) = vec_len (_pool_var (b)); \
448 _pool_var (len) = vec_len (POOL); \
449 _pool_var (lo) = 0; \
451 for (_pool_var (i) = 0; \
452 _pool_var (i) <= _pool_var (bl); \
455 uword _pool_var (m), _pool_var (f); \
456 _pool_var (m) = (_pool_var (i) < _pool_var (bl) \
457 ? _pool_var (b) [_pool_var (i)] \
459 while (_pool_var (m) != 0) \
461 _pool_var (f) = first_set (_pool_var (m)); \
462 _pool_var (hi) = (_pool_var (i) * BITS (_pool_var (b)[0]) \
463 + min_log2 (_pool_var (f))); \
464 _pool_var (hi) = (_pool_var (i) < _pool_var (bl) \
465 ? _pool_var (hi) : _pool_var (len)); \
466 _pool_var (m) ^= _pool_var (f); \
467 if (_pool_var (hi) > _pool_var (lo)) \
469 (LO) = _pool_var (lo); \
470 (HI) = _pool_var (hi); \
471 do { BODY; } while (0); \
473 _pool_var (lo) = _pool_var (hi) + 1; \
478 /** Iterate through pool.
480 @param VAR A variable of same type as pool vector to be used as an
482 @param POOL The pool to iterate across.
483 @param BODY The operation to perform, typically a code block. See
486 This macro will call @c BODY with each active pool element.
488 It is a bad idea to allocate or free pool element from within
489 @c pool_foreach. Build a vector of indices and dispose of them later.
495 proc_t *procs; // a pool of processes.
496 proc_t *proc; // pointer to one process; used as the iterator.
498 pool_foreach (proc, procs, ({
499 if (proc->state != PROC_STATE_RUNNING)
502 // check a running proc in some way
507 @warning Because @c pool_foreach is a macro, syntax errors can be
508 difficult to find inside @c BODY, let alone actual code bugs. One
509 can temporarily split a complex @c pool_foreach into a trivial
510 @c pool_foreach which builds a vector of active indices, and a
511 vec_foreach() (or plain for-loop) to walk the active index vector.
513 #define pool_foreach(VAR,POOL,BODY) \
515 uword _pool_foreach_lo, _pool_foreach_hi; \
516 pool_foreach_region (_pool_foreach_lo, _pool_foreach_hi, (POOL), \
518 for ((VAR) = (POOL) + _pool_foreach_lo; \
519 (VAR) < (POOL) + _pool_foreach_hi; \
521 do { BODY; } while (0); \
525 /** Returns pointer to element at given index.
527 ASSERTs that the supplied index is valid.
528 Even though one can write correct code of the form
530 p = pool_base + index;
532 use of @c pool_elt_at_index is strongly suggested.
534 #define pool_elt_at_index(p,i) \
536 typeof (p) _e = (p) + (i); \
537 ASSERT (! pool_is_free (p, _e)); \
541 /** Return next occupied pool index after @c i, useful for safe iteration. */
542 #define pool_next_index(P,I) \
544 pool_header_t * _pool_var (p) = pool_header (P); \
545 uword _pool_var (rv) = (I) + 1; \
548 (_pool_var (rv) < vec_len (P) ? \
549 clib_bitmap_next_clear (_pool_var (p)->free_bitmap, _pool_var(rv)) \
552 (_pool_var (rv) < vec_len (P) ? \
553 _pool_var (rv) : ~0); \
557 /** Iterate pool by index. */
558 #define pool_foreach_index(i,v,body) \
559 for ((i) = 0; (i) < vec_len (v); (i)++) \
561 if (! pool_is_free_index ((v), (i))) \
562 do { body; } while (0); \
566 * @brief Remove all elements from a pool in a safe way
568 * @param VAR each element in the pool
569 * @param POOL The pool to flush
570 * @param BODY The actions to perform on each element before it is returned to
571 * the pool. i.e. before it is 'freed'
573 #define pool_flush(VAR, POOL, BODY) \
575 uword *_pool_var(ii), *_pool_var(dv) = NULL; \
577 pool_foreach((VAR), (POOL), \
579 vec_add1(_pool_var(dv), (VAR) - (POOL)); \
581 vec_foreach(_pool_var(ii), _pool_var(dv)) \
583 (VAR) = pool_elt_at_index((POOL), *_pool_var(ii)); \
584 do { BODY; } while (0); \
585 pool_put((POOL), (VAR)); \
587 vec_free(_pool_var(dv)); \
590 #endif /* included_pool_h */
593 * fd.io coding-style-patch-verification: ON
596 * eval: (c-set-style "gnu")