aboutsummaryrefslogtreecommitdiffstats
path: root/lib/librte_mempool/rte_mempool.h
blob: 9745bf0d70b4a9e238f68652aca01f78c7ba6dad (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
/*-
 *   BSD LICENSE
 *
 *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef _RTE_MEMPOOL_H_
#define _RTE_MEMPOOL_H_

/**
 * @file
 * RTE Mempool.
 *
 * A memory pool is an allocator of fixed-size object. It is
 * identified by its name, and uses a ring to store free objects. It
 * provides some other optional services, like a per-core object
 * cache, and an alignment helper to ensure that objects are padded
 * to spread them equally on all RAM channels, ranks, and so on.
 *
 * Objects owned by a mempool should never be added in another
 * mempool. When an object is freed using rte_mempool_put() or
 * equivalent, the object data is not modified; the user can save some
 * meta-data in the object data and retrieve them when allocating a
 * new object.
 *
 * Note: the mempool implementation is not preemptable. A lcore must
 * not be interrupted by another task that uses the same mempool
 * (because it uses a ring which is not preemptable). Also, mempool
 * functions must not be used outside the DPDK environment: for
 * example, in linuxapp environment, a thread that is not created by
 * the EAL must not use mempools. This is due to the per-lcore cache
 * that won't work as rte_lcore_id() will not return a correct value.
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <errno.h>
#include <inttypes.h>
#include <sys/queue.h>

#include <rte_log.h>
#include <rte_debug.h>
#include <rte_lcore.h>
#include <rte_memory.h>
#include <rte_branch_prediction.h>
#include <rte_ring.h>

#ifdef __cplusplus
extern "C" {
#endif

#define RTE_MEMPOOL_HEADER_COOKIE1  0xbadbadbadadd2e55ULL /**< Header cookie. */
#define RTE_MEMPOOL_HEADER_COOKIE2  0xf2eef2eedadd2e55ULL /**< Header cookie. */
#define RTE_MEMPOOL_TRAILER_COOKIE  0xadd2e55badbadbadULL /**< Trailer cookie.*/

#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
/**
 * A structure that stores the mempool statistics (per-lcore).
 */
struct rte_mempool_debug_stats {
	uint64_t put_bulk;         /**< Number of puts. */
	uint64_t put_objs;         /**< Number of objects successfully put. */
	uint64_t get_success_bulk; /**< Successful allocation number. */
	uint64_t get_success_objs; /**< Objects successfully allocated. */
	uint64_t get_fail_bulk;    /**< Failed allocation number. */
	uint64_t get_fail_objs;    /**< Objects that failed to be allocated. */
} __rte_cache_aligned;
#endif

#if RTE_MEMPOOL_CACHE_MAX_SIZE > 0
/**
 * A structure that stores a per-core object cache.
 */
struct rte_mempool_cache {
	unsigned len; /**< Cache len */
	/*
	 * Cache is allocated to this size to allow it to overflow in certain
	 * cases to avoid needless emptying of cache.
	 */
	void *objs[RTE_MEMPOOL_CACHE_MAX_SIZE * 3]; /**< Cache objects */
} __rte_cache_aligned;
#endif /* RTE_MEMPOOL_CACHE_MAX_SIZE > 0 */

/**
 * A structure that stores the size of mempool elements.
 */
struct rte_mempool_objsz {
	uint32_t elt_size;     /**< Size of an element. */
	uint32_t header_size;  /**< Size of header (before elt). */
	uint32_t trailer_size; /**< Size of trailer (after elt). */
	uint32_t total_size;
	/**< Total size of an object (header + elt + trailer). */
};

#define RTE_MEMPOOL_NAMESIZE 32 /**< Maximum length of a memory pool. */
#define RTE_MEMPOOL_MZ_PREFIX "MP_"

/* "MP_<name>" */
#define	RTE_MEMPOOL_MZ_FORMAT	RTE_MEMPOOL_MZ_PREFIX "%s"

#ifdef RTE_LIBRTE_XEN_DOM0

/* "<name>_MP_elt" */
#define	RTE_MEMPOOL_OBJ_NAME	"%s_" RTE_MEMPOOL_MZ_PREFIX "elt"

#else

#define	RTE_MEMPOOL_OBJ_NAME	RTE_MEMPOOL_MZ_FORMAT

#endif /* RTE_LIBRTE_XEN_DOM0 */

#define	MEMPOOL_PG_SHIFT_MAX	(sizeof(uintptr_t) * CHAR_BIT - 1)

/** Mempool over one chunk of physically continuous memory */
#define	MEMPOOL_PG_NUM_DEFAULT	1

#ifndef RTE_MEMPOOL_ALIGN
#define RTE_MEMPOOL_ALIGN	RTE_CACHE_LINE_SIZE
#endif

#define RTE_MEMPOOL_ALIGN_MASK	(RTE_MEMPOOL_ALIGN - 1)

/**
 * Mempool object header structure
 *
 * Each object stored in mempools are prefixed by this header structure,
 * it allows to retrieve the mempool pointer from the object. When debug
 * is enabled, a cookie is also added in this structure preventing
 * corruptions and double-frees.
 */
struct rte_mempool_objhdr {
	struct rte_mempool *mp;          /**< The mempool owning the object. */
#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
	uint64_t cookie;                 /**< Debug cookie. */
#endif
};

/**
 * Mempool object trailer structure
 *
 * In debug mode, each object stored in mempools are suffixed by this
 * trailer structure containing a cookie preventing memory corruptions.
 */
struct rte_mempool_objtlr {
#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
	uint64_t cookie;                 /**< Debug cookie. */
#endif
};

/**
 * The RTE mempool structure.
 */
struct rte_mempool {
	char name[RTE_MEMPOOL_NAMESIZE]; /**< Name of mempool. */
	struct rte_ring *ring;           /**< Ring to store objects. */
	phys_addr_t phys_addr;           /**< Phys. addr. of mempool struct. */
	int flags;                       /**< Flags of the mempool. */
	uint32_t size;                   /**< Size of the mempool. */
	uint32_t cache_size;             /**< Size of per-lcore local cache. */
	uint32_t cache_flushthresh;
	/**< Threshold before we flush excess elements. */

	uint32_t elt_size;               /**< Size of an element. */
	uint32_t header_size;            /**< Size of header (before elt). */
	uint32_t trailer_size;           /**< Size of trailer (after elt). */

	unsigned private_data_size;      /**< Size of private data. */

#if RTE_MEMPOOL_CACHE_MAX_SIZE > 0
	/** Per-lcore local cache. */
	struct rte_mempool_cache local_cache[RTE_MAX_LCORE];
#endif

#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
	/** Per-lcore statistics. */
	struct rte_mempool_debug_stats stats[RTE_MAX_LCORE];
#endif

	/* Address translation support, starts from next cache line. */

	/** Number of elements in the elt_pa array. */
	uint32_t    pg_num __rte_cache_aligned;
	uint32_t    pg_shift;     /**< LOG2 of the physical pages. */
	uintptr_t   pg_mask;      /**< physical page mask value. */
	uintptr_t   elt_va_start;
	/**< Virtual address of the first mempool object. */
	uintptr_t   elt_va_end;
	/**< Virtual address of the <size + 1> mempool object. */
	phys_addr_t elt_pa[MEMPOOL_PG_NUM_DEFAULT];
	/**< Array of physical page addresses for the mempool objects buffer. */

}  __rte_cache_aligned;

#define MEMPOOL_F_NO_SPREAD      0x0001 /**< Do not spread in memory. */
#define MEMPOOL_F_NO_CACHE_ALIGN 0x0002 /**< Do not align objs on cache lines.*/
#define MEMPOOL_F_SP_PUT         0x0004 /**< Default put is "single-producer".*/
#define MEMPOOL_F_SC_GET         0x0008 /**< Default get is "single-consumer".*/

/**
 * @internal When debug is enabled, store some statistics.
 *
 * @param mp
 *   Pointer to the memory pool.
 * @param name
 *   Name of the statistics field to increment in the memory pool.
 * @param n
 *   Number to add to the object-oriented statistics.
 */
#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
#define __MEMPOOL_STAT_ADD(mp, name, n) do {                    \
		unsigned __lcore_id = rte_lcore_id();           \
		if (__lcore_id < RTE_MAX_LCORE) {               \
			mp->stats[__lcore_id].name##_objs += n;	\
			mp->stats[__lcore_id].name##_bulk += 1;	\
		}                                               \
	} while(0)
#else
#define __MEMPOOL_STAT_ADD(mp, name, n) do {} while(0)
#endif

/**
 * Calculate the size of the mempool header.
 *
 * @param mp
 *   Pointer to the memory pool.
 * @param pgn
 *   Number of pages used to store mempool objects.
 */
#define	MEMPOOL_HEADER_SIZE(mp, pgn)	(sizeof(*(mp)) + \
	RTE_ALIGN_CEIL(((pgn) - RTE_DIM((mp)->elt_pa)) * \
	sizeof ((mp)->elt_pa[0]), RTE_CACHE_LINE_SIZE))

/**
 * Return true if the whole mempool is in contiguous memory.
 */
#define	MEMPOOL_IS_CONTIG(mp)                      \
	((mp)->pg_num == MEMPOOL_PG_NUM_DEFAULT && \
	(mp)->phys_addr == (mp)->elt_pa[0])

/* return the header of a mempool object (internal) */
static inline struct rte_mempool_objhdr *__mempool_get_header(void *obj)
{
	return (struct rte_mempool_objhdr *)RTE_PTR_SUB(obj, sizeof(struct rte_mempool_objhdr));
}

/**
 * Return a pointer to the mempool owning this object.
 *
 * @param obj
 *   An object that is owned by a pool. If this is not the case,
 *   the behavior is undefined.
 * @return
 *   A pointer to the mempool structure.
 */
static inline struct rte_mempool *rte_mempool_from_obj(void *obj)
{
	struct rte_mempool_objhdr *hdr = __mempool_get_header(obj);
	return hdr->mp;
}

/* return the trailer of a mempool object (internal) */
static inline struct rte_mempool_objtlr *__mempool_get_trailer(void *obj)
{
	struct rte_mempool *mp = rte_mempool_from_obj(obj);
	return (struct rte_mempool_objtlr *)RTE_PTR_ADD(obj, mp->elt_size);
}

/**
 * @internal Check and update cookies or panic.
 *
 * @param mp
 *   Pointer to the memory pool.
 * @param obj_table_const
 *   Pointer to a table of void * pointers (objects).
 * @param n
 *   Index of object in object table.
 * @param free
 *   - 0: object is supposed to be allocated, mark it as free
 *   - 1: object is supposed to be free, mark it as allocated
 *   - 2: just check that cookie is valid (free or allocated)
 */
#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
#ifndef __INTEL_COMPILER
#pragma GCC diagnostic ignored "-Wcast-qual"
#endif
static inline void __mempool_check_cookies(const struct rte_mempool *mp,
					   void * const *obj_table_const,
					   unsigned n, int free)
{
	struct rte_mempool_objhdr *hdr;
	struct rte_mempool_objtlr *tlr;
	uint64_t cookie;
	void *tmp;
	void *obj;
	void **obj_table;

	/* Force to drop the "const" attribute. This is done only when
	 * DEBUG is enabled */
	tmp = (void *) obj_table_const;
	obj_table = (void **) tmp;

	while (n--) {
		obj = obj_table[n];

		if (rte_mempool_from_obj(obj) != mp)
			rte_panic("MEMPOOL: object is owned by another "
				  "mempool\n");

		hdr = __mempool_get_header(obj);
		cookie = hdr->cookie;

		if (free == 0) {
			if (cookie != RTE_MEMPOOL_HEADER_COOKIE1) {
				rte_log_set_history(0);
				RTE_LOG(CRIT, MEMPOOL,
					"obj=%p, mempool=%p, cookie=%" PRIx64 "\n",
					obj, (const void *) mp, cookie);
				rte_panic("MEMPOOL: bad header cookie (put)\n");
			}
			hdr->cookie = RTE_MEMPOOL_HEADER_COOKIE2;
		}
		else if (free == 1) {
			if (cookie != RTE_MEMPOOL_HEADER_COOKIE2) {
				rte_log_set_history(0);
				RTE_LOG(CRIT, MEMPOOL,
					"obj=%p, mempool=%p, cookie=%" PRIx64 "\n",
					obj, (const void *) mp, cookie);
				rte_panic("MEMPOOL: bad header cookie (get)\n");
			}
			hdr->cookie = RTE_MEMPOOL_HEADER_COOKIE1;
		}
		else if (free == 2) {
			if (cookie != RTE_MEMPOOL_HEADER_COOKIE1 &&
			    cookie != RTE_MEMPOOL_HEADER_COOKIE2) {
				rte_log_set_history(0);
				RTE_LOG(CRIT, MEMPOOL,
					"obj=%p, mempool=%p, cookie=%" PRIx64 "\n",
					obj, (const void *) mp, cookie);
				rte_panic("MEMPOOL: bad header cookie (audit)\n");
			}
		}
		tlr = __mempool_get_trailer(obj);
		cookie = tlr->cookie;
		if (cookie != RTE_MEMPOOL_TRAILER_COOKIE) {
			rte_log_set_history(0);
			RTE_LOG(CRIT, MEMPOOL,
				"obj=%p, mempool=%p, cookie=%" PRIx64 "\n",
				obj, (const void *) mp, cookie);
			rte_panic("MEMPOOL: bad trailer cookie\n");
		}
	}
}
#ifndef __INTEL_COMPILER
#pragma GCC diagnostic error "-Wcast-qual"
#endif
#else
#define __mempool_check_cookies(mp, obj_table_const, n, free) do {} while(0)
#endif /* RTE_LIBRTE_MEMPOOL_DEBUG */

/**
 * A mempool object iterator callback function.
 */
typedef void (*rte_mempool_obj_iter_t)(void * /*obj_iter_arg*/,
	void * /*obj_start*/,
	void * /*obj_end*/,
	uint32_t /*obj_index */);

/**
 * Call a function for each mempool object in a memory chunk
 *
 * Iterate across objects of the given size and alignment in the
 * provided chunk of memory. The given memory buffer can consist of
 * disjointed physical pages.
 *
 * For each object, call the provided callback (if any). This function
 * is used to populate a mempool, or walk through all the elements of a
 * mempool, or estimate how many elements of the given size could be
 * created in the given memory buffer.
 *
 * @param vaddr
 *   Virtual address of the memory buffer.
 * @param elt_num
 *   Maximum number of objects to iterate through.
 * @param elt_sz
 *   Size of each object.
 * @param align
 *   Alignment of each object.
 * @param paddr
 *   Array of physical addresses of the pages that comprises given memory
 *   buffer.
 * @param pg_num
 *   Number of elements in the paddr array.
 * @param pg_shift
 *   LOG2 of the physical pages size.
 * @param obj_iter
 *   Object iterator callback function (could be NULL).
 * @param obj_iter_arg
 *   User defined parameter for the object iterator callback function.
 *
 * @return
 *   Number of objects iterated through.
 */
uint32_t rte_mempool_obj_iter(void *vaddr,
	uint32_t elt_num, size_t elt_sz, size_t align,
	const phys_addr_t paddr[], uint32_t pg_num, uint32_t pg_shift,
	rte_mempool_obj_iter_t obj_iter, void *obj_iter_arg);

/**
 * An object constructor callback function for mempool.
 *
 * Arguments are the mempool, the opaque pointer given by the user in
 * rte_mempool_create(), the pointer to the element and the index of
 * the element in the pool.
 */
typedef void (rte_mempool_obj_ctor_t)(struct rte_mempool *, void *,
				      void *, unsigned);

/**
 * A mempool constructor callback function.
 *
 * Arguments are the mempool and the opaque pointer given by the user in
 * rte_mempool_create().
 */
typedef void (rte_mempool_ctor_t)(struct rte_mempool *, void *);

/**
 * Create a new mempool named *name* in memory.
 *
 * This function uses ``memzone_reserve()`` to allocate memory. The
 * pool contains n elements of elt_size. Its size is set to n.
 * All elements of the mempool are allocated together with the mempool header,
 * in one physically continuous chunk of memory.
 *
 * @param name
 *   The name of the mempool.
 * @param n
 *   The number of elements in the mempool. The optimum size (in terms of
 *   memory usage) for a mempool is when n is a power of two minus one:
 *   n = (2^q - 1).
 * @param elt_size
 *   The size of each element.
 * @param cache_size
 *   If cache_size is non-zero, the rte_mempool library will try to
 *   limit the accesses to the common lockless pool, by maintaining a
 *   per-lcore object cache. This argument must be lower or equal to
 *   CONFIG_RTE_MEMPOOL_CACHE_MAX_SIZE and n / 1.5. It is advised to choose
 *   cache_size to have "n modulo cache_size == 0": if this is
 *   not the case, some elements will always stay in the pool and will
 *   never be used. The access to the per-lcore table is of course
 *   faster than the multi-producer/consumer pool. The cache can be
 *   disabled if the cache_size argument is set to 0; it can be useful to
 *   avoid losing objects in cache. Note that even if not used, the
 *   memory space for cache is always reserved in a mempool structure,
 *   except if CONFIG_RTE_MEMPOOL_CACHE_MAX_SIZE is set to 0.
 * @param private_data_size
 *   The size of the private data appended after the mempool
 *   structure. This is useful for storing some private data after the
 *   mempool structure, as is done for rte_mbuf_pool for example.
 * @param mp_init
 *   A function pointer that is called for initialization of the pool,
 *   before object initialization. The user can initialize the private
 *   data in this function if needed. This parameter can be NULL if
 *   not needed.
 * @param mp_init_arg
 *   An opaque pointer to data that can be used in the mempool
 *   constructor function.
 * @param obj_init
 *   A function pointer that is called for each object at
 *   initialization of the pool. The user can set some meta data in
 *   objects if needed. This parameter can be NULL if not needed.
 *   The obj_init() function takes the mempool pointer, the init_arg,
 *   the object pointer and the object number as parameters.
 * @param obj_init_arg
 *   An opaque pointer to data that can be used as an argument for
 *   each call to the object constructor function.
 * @param socket_id
 *   The *socket_id* argument is the socket identifier in the case of
 *   NUMA. The value can be *SOCKET_ID_ANY* if there is no NUMA
 *   constraint for the reserved zone.
 * @param flags
 *   The *flags* arguments is an OR of following flags:
 *   - MEMPOOL_F_NO_SPREAD: By default, objects addresses are spread
 *     between channels in RAM: the pool allocator will add padding
 *     between objects depending on the hardware configuration. See
 *     Memory alignment constraints for details. If this flag is set,
 *     the allocator will just align them to a cache line.
 *   - MEMPOOL_F_NO_CACHE_ALIGN: By default, the returned objects are
 *     cache-aligned. This flag removes this constraint, and no
 *     padding will be present between objects. This flag implies
 *     MEMPOOL_F_NO_SPREAD.
 *   - MEMPOOL_F_SP_PUT: If this flag is set, the default behavior
 *     when using rte_mempool_put() or rte_mempool_put_bulk() is
 *     "single-producer". Otherwise, it is "multi-producers".
 *   - MEMPOOL_F_SC_GET: If this flag is set, the default behavior
 *     when using rte_mempool_get() or rte_mempool_get_bulk() is
 *     "single-consumer". Otherwise, it is "multi-consumers".
 * @return
 *   The pointer to the new allocated mempool, on success. NULL on error
 *   with rte_errno set appropriately. Possible rte_errno values include:
 *    - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
 *    - E_RTE_SECONDARY - function was called from a secondary process instance
 *    - EINVAL - cache size provided is too large
 *    - ENOSPC - the maximum number of memzones has already been allocated
 *    - EEXIST - a memzone with the same name already exists
 *    - ENOMEM - no appropriate memory area found in which to create memzone
 */
struct rte_mempool *
rte_mempool_create(const char *name, unsigned n, unsigned elt_size,
		   unsigned cache_size, unsigned private_data_size,
		   rte_mempool_ctor_t *mp_init, void *mp_init_arg,
		   rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg,
		   int socket_id, unsigned flags);

/**
 * Create a new mempool named *name* in memory.
 *
 * This function uses ``memzone_reserve()`` to allocate memory. The
 * pool contains n elements of elt_size. Its size is set to n.
 * Depending on the input parameters, mempool elements can be either allocated
 * together with the mempool header, or an externally provided memory buffer
 * could be used to store mempool objects. In later case, that external
 * memory buffer can consist of set of disjoint physical pages.
 *
 * @param name
 *   The name of the mempool.
 * @param n
 *   The number of elements in the mempool. The optimum size (in terms of
 *   memory usage) for a mempool is when n is a power of two minus one:
 *   n = (2^q - 1).
 * @param elt_size
 *   The size of each element.
 * @param cache_size
 *   If cache_size is non-zero, the rte_mempool library will try to
 *   limit the accesses to the common lockless pool, by maintaining a
 *   per-lcore object cache. This argument must be lower or equal to
 *   CONFIG_RTE_MEMPOOL_CACHE_MAX_SIZE. It is advised to choose
 *   cache_size to have "n modulo cache_size == 0": if this is
 *   not the case, some elements will always stay in the pool and will
 *   never be used. The access to the per-lcore table is of course
 *   faster than the multi-producer/consumer pool. The cache can be
 *   disabled if the cache_size argument is set to 0; it can be useful to
 *   avoid losing objects in cache. Note that even if not used, the
 *   memory space for cache is always reserved in a mempool structure,
 *   except if CONFIG_RTE_MEMPOOL_CACHE_MAX_SIZE is set to 0.
 * @param private_data_size
 *   The size of the private data appended after the mempool
 *   structure. This is useful for storing some private data after the
 *   mempool structure, as is done for rte_mbuf_pool for example.
 * @param mp_init
 *   A function pointer that is called for initialization of the pool,
 *   before object initialization. The user can initialize the private
 *   data in this function if needed. This parameter can be NULL if
 *   not needed.
 * @param mp_init_arg
 *   An opaque pointer to data that can be used in the mempool
 *   constructor function.
 * @param obj_init
 *   A function pointer that is called for each object at
 *   initialization of the pool. The user can set some meta data in
 *   objects if needed. This parameter can be NULL if not needed.
 *   The obj_init() function takes the mempool pointer, the init_arg,
 *   the object pointer and the object number as parameters.
 * @param obj_init_arg
 *   An opaque pointer to data that can be used as an argument for
 *   each call to the object constructor function.
 * @param socket_id
 *   The *socket_id* argument is the socket identifier in the case of
 *   NUMA. The value can be *SOCKET_ID_ANY* if there is no NUMA
 *   constraint for the reserved zone.
 * @param flags
 *   The *flags* arguments is an OR of following flags:
 *   - MEMPOOL_F_NO_SPREAD: By default, objects addresses are spread
 *     between channels in RAM: the pool allocator will add padding
 *     between objects depending on the hardware configuration. See
 *     Memory alignment constraints for details. If this flag is set,
 *     the allocator will just align them to a cache line.
 *   - MEMPOOL_F_NO_CACHE_ALIGN: By default, the returned objects are
 *     cache-aligned. This flag removes this constraint, and no
 *     padding will be present between objects. This flag implies
 *     MEMPOOL_F_NO_SPREAD.
 *   - MEMPOOL_F_SP_PUT: If this flag is set, the default behavior
 *     when using rte_mempool_put() or rte_mempool_put_bulk() is
 *     "single-producer". Otherwise, it is "multi-producers".
 *   - MEMPOOL_F_SC_GET: If this flag is set, the default behavior
 *     when using rte_mempool_get() or rte_mempool_get_bulk() is
 *     "single-consumer". Otherwise, it is "multi-consumers".
 * @param vaddr
 *   Virtual address of the externally allocated memory buffer.
 *   Will be used to store mempool objects.
 * @param paddr
 *   Array of physical addresses of the pages that comprises given memory
 *   buffer.
 * @param pg_num
 *   Number of elements in the paddr array.
 * @param pg_shift
 *   LOG2 of the physical pages size.
 * @return
 *   The pointer to the new allocated mempool, on success. NULL on error
 *   with rte_errno set appropriately. Possible rte_errno values include:
 *    - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
 *    - E_RTE_SECONDARY - function was called from a secondary process instance
 *    - EINVAL - cache size provided is too large
 *    - ENOSPC - the maximum number of memzones has already been allocated
 *    - EEXIST - a memzone with the same name already exists
 *    - ENOMEM - no appropriate memory area found in which to create memzone
 */
struct rte_mempool *
rte_mempool_xmem_create(const char *name, unsigned n, unsigned elt_size,
		unsigned cache_size, unsigned private_data_size,
		rte_mempool_ctor_t *mp_init, void *mp_init_arg,
		rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg,
		int socket_id, unsigned flags, void *vaddr,
		const phys_addr_t paddr[], uint32_t pg_num, uint32_t pg_shift);

/**
 * Create a new mempool named *name* in memory on Xen Dom0.
 *
 * This function uses ``rte_mempool_xmem_create()`` to allocate memory. The
 * pool contains n elements of elt_size. Its size is set to n.
 * All elements of the mempool are allocated together with the mempool header,
 * and memory buffer can consist of set of disjoint physical pages.
 *
 * @param name
 *   The name of the mempool.
 * @param n
 *   The number of elements in the mempool. The optimum size (in terms of
 *   memory usage) for a mempool is when n is a power of two minus one:
 *   n = (2^q - 1).
 * @param elt_size
 *   The size of each element.
 * @param cache_size
 *   If cache_size is non-zero, the rte_mempool library will try to
 *   limit the accesses to the common lockless pool, by maintaining a
 *   per-lcore object cache. This argument must be lower or equal to
 *   CONFIG_RTE_MEMPOOL_CACHE_MAX_SIZE. It is advised to choose
 *   cache_size to have "n modulo cache_size == 0": if this is
 *   not the case, some elements will always stay in the pool and will
 *   never be used. The access to the per-lcore table is of course
 *   faster than the multi-producer/consumer pool. The cache can be
 *   disabled if the cache_size argument is set to 0; it can be useful to
 *   avoid losing objects in cache. Note that even if not used, the
 *   memory space for cache is always reserved in a mempool structure,
 *   except if CONFIG_RTE_MEMPOOL_CACHE_MAX_SIZE is set to 0.
 * @param private_data_size
 *   The size of the private data appended after the mempool
 *   structure. This is useful for storing some private data after the
 *   mempool structure, as is done for rte_mbuf_pool for example.
 * @param mp_init
 *   A function pointer that is called for initialization of the pool,
 *   before object initialization. The user can initialize the private
 *   data in this function if needed. This parameter can be NULL if
 *   not needed.
 * @param mp_init_arg
 *   An opaque pointer to data that can be used in the mempool
 *   constructor function.
 * @param obj_init
 *   A function pointer that is called for each object at
 *   initialization of the pool. The user can set some meta data in
 *   objects if needed. This parameter can be NULL if not needed.
 *   The obj_init() function takes the mempool pointer, the init_arg,
 *   the object pointer and the object number as parameters.
 * @param obj_init_arg
 *   An opaque pointer to data that can be used as an argument for
 *   each call to the object constructor function.
 * @param socket_id
 *   The *socket_id* argument is the socket identifier in the case of
 *   NUMA. The value can be *SOCKET_ID_ANY* if there is no NUMA
 *   constraint for the reserved zone.
 * @param flags
 *   The *flags* arguments is an OR of following flags:
 *   - MEMPOOL_F_NO_SPREAD: By default, objects addresses are spread
 *     between channels in RAM: the pool allocator will add padding
 *     between objects depending on the hardware configuration. See
 *     Memory alignment constraints for details. If this flag is set,
 *     the allocator will just align them to a cache line.
 *   - MEMPOOL_F_NO_CACHE_ALIGN: By default, the returned objects are
 *     cache-aligned. This flag removes this constraint, and no
 *     padding will be present between objects. This flag implies
 *     MEMPOOL_F_NO_SPREAD.
 *   - MEMPOOL_F_SP_PUT: If this flag is set, the default behavior
 *     when using rte_mempool_put() or rte_mempool_put_bulk() is
 *     "single-producer". Otherwise, it is "multi-producers".
 *   - MEMPOOL_F_SC_GET: If this flag is set, the default behavior
 *     when using rte_mempool_get() or rte_mempool_get_bulk() is
 *     "single-consumer". Otherwise, it is "multi-consumers".
 * @return
 *   The pointer to the new allocated mempool, on success. NULL on error
 *   with rte_errno set appropriately. Possible rte_errno values include:
 *    - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
 *    - E_RTE_SECONDARY - function was called from a secondary process instance
 *    - EINVAL - cache size provided is too large
 *    - ENOSPC - the maximum number of memzones has already been allocated
 *    - EEXIST - a memzone with the same name already exists
 *    - ENOMEM - no appropriate memory area found in which to create memzone
 */
struct rte_mempool *
rte_dom0_mempool_create(const char *name, unsigned n, unsigned elt_size,
		unsigned cache_size, unsigned private_data_size,
		rte_mempool_ctor_t *mp_init, void *mp_init_arg,
		rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg,
		int socket_id, unsigned flags);


/**
 * Dump the status of the mempool to the console.
 *
 * @param f
 *   A pointer to a file for output
 * @param mp
 *   A pointer to the mempool structure.
 */
void rte_mempool_dump(FILE *f, const struct rte_mempool *mp);

/**
 * @internal Put several objects back in the mempool; used internally.
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_table
 *   A pointer to a table of void * pointers (objects).
 * @param n
 *   The number of objects to store back in the mempool, must be strictly
 *   positive.
 * @param is_mp
 *   Mono-producer (0) or multi-producers (1).
 */
static inline void __attribute__((always_inline))
__mempool_put_bulk(struct rte_mempool *mp, void * const *obj_table,
		    unsigned n, int is_mp)
{
#if RTE_MEMPOOL_CACHE_MAX_SIZE > 0
	struct rte_mempool_cache *cache;
	uint32_t index;
	void **cache_objs;
	unsigned lcore_id = rte_lcore_id();
	uint32_t cache_size = mp->cache_size;
	uint32_t flushthresh = mp->cache_flushthresh;
#endif /* RTE_MEMPOOL_CACHE_MAX_SIZE > 0 */

	/* increment stat now, adding in mempool always success */
	__MEMPOOL_STAT_ADD(mp, put, n);

#if RTE_MEMPOOL_CACHE_MAX_SIZE > 0
	/* cache is not enabled or single producer or non-EAL thread */
	if (unlikely(cache_size == 0 || is_mp == 0 ||
		     lcore_id >= RTE_MAX_LCORE))
		goto ring_enqueue;

	/* Go straight to ring if put would overflow mem allocated for cache */
	if (unlikely(n > RTE_MEMPOOL_CACHE_MAX_SIZE))
		goto ring_enqueue;

	cache = &mp->local_cache[lcore_id];
	cache_objs = &cache->objs[cache->len];

	/*
	 * The cache follows the following algorithm
	 *   1. Add the objects to the cache
	 *   2. Anything greater than the cache min value (if it crosses the
	 *   cache flush threshold) is flushed to the ring.
	 */

	/* Add elements back into the cache */
	for (index = 0; index < n; ++index, obj_table++)
		cache_objs[index] = *obj_table;

	cache->len += n;

	if (cache->len >= flushthresh) {
		rte_ring_mp_enqueue_bulk(mp->ring, &cache->objs[cache_size],
				cache->len - cache_size);
		cache->len = cache_size;
	}

	return;

ring_enqueue:
#endif /* RTE_MEMPOOL_CACHE_MAX_SIZE > 0 */

	/* push remaining objects in ring */
#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
	if (is_mp) {
		if (rte_ring_mp_enqueue_bulk(mp->ring, obj_table, n) < 0)
			rte_panic("cannot put objects in mempool\n");
	}
	else {
		if (rte_ring_sp_enqueue_bulk(mp->ring, obj_table, n) < 0)
			rte_panic("cannot put objects in mempool\n");
	}
#else
	if (is_mp)
		rte_ring_mp_enqueue_bulk(mp->ring, obj_table, n);
	else
		rte_ring_sp_enqueue_bulk(mp->ring, obj_table, n);
#endif
}


/**
 * Put several objects back in the mempool (multi-producers safe).
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_table
 *   A pointer to a table of void * pointers (objects).
 * @param n
 *   The number of objects to add in the mempool from the obj_table.
 */
static inline void __attribute__((always_inline))
rte_mempool_mp_put_bulk(struct rte_mempool *mp, void * const *obj_table,
			unsigned n)
{
	__mempool_check_cookies(mp, obj_table, n, 0);
	__mempool_put_bulk(mp, obj_table, n, 1);
}

/**
 * Put several objects back in the mempool (NOT multi-producers safe).
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_table
 *   A pointer to a table of void * pointers (objects).
 * @param n
 *   The number of objects to add in the mempool from obj_table.
 */
static inline void
rte_mempool_sp_put_bulk(struct rte_mempool *mp, void * const *obj_table,
			unsigned n)
{
	__mempool_check_cookies(mp, obj_table, n, 0);
	__mempool_put_bulk(mp, obj_table, n, 0);
}

/**
 * Put several objects back in the mempool.
 *
 * This function calls the multi-producer or the single-producer
 * version depending on the default behavior that was specified at
 * mempool creation time (see flags).
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_table
 *   A pointer to a table of void * pointers (objects).
 * @param n
 *   The number of objects to add in the mempool from obj_table.
 */
static inline void __attribute__((always_inline))
rte_mempool_put_bulk(struct rte_mempool *mp, void * const *obj_table,
		     unsigned n)
{
	__mempool_check_cookies(mp, obj_table, n, 0);
	__mempool_put_bulk(mp, obj_table, n, !(mp->flags & MEMPOOL_F_SP_PUT));
}

/**
 * Put one object in the mempool (multi-producers safe).
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj
 *   A pointer to the object to be added.
 */
static inline void __attribute__((always_inline))
rte_mempool_mp_put(struct rte_mempool *mp, void *obj)
{
	rte_mempool_mp_put_bulk(mp, &obj, 1);
}

/**
 * Put one object back in the mempool (NOT multi-producers safe).
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj
 *   A pointer to the object to be added.
 */
static inline void __attribute__((always_inline))
rte_mempool_sp_put(struct rte_mempool *mp, void *obj)
{
	rte_mempool_sp_put_bulk(mp, &obj, 1);
}

/**
 * Put one object back in the mempool.
 *
 * This function calls the multi-producer or the single-producer
 * version depending on the default behavior that was specified at
 * mempool creation time (see flags).
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj
 *   A pointer to the object to be added.
 */
static inline void __attribute__((always_inline))
rte_mempool_put(struct rte_mempool *mp, void *obj)
{
	rte_mempool_put_bulk(mp, &obj, 1);
}

/**
 * @internal Get several objects from the mempool; used internally.
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_table
 *   A pointer to a table of void * pointers (objects).
 * @param n
 *   The number of objects to get, must be strictly positive.
 * @param is_mc
 *   Mono-consumer (0) or multi-consumers (1).
 * @return
 *   - >=0: Success; number of objects supplied.
 *   - <0: Error; code of ring dequeue function.
 */
static inline int __attribute__((always_inline))
__mempool_get_bulk(struct rte_mempool *mp, void **obj_table,
		   unsigned n, int is_mc)
{
	int ret;
#if RTE_MEMPOOL_CACHE_MAX_SIZE > 0
	struct rte_mempool_cache *cache;
	uint32_t index, len;
	void **cache_objs;
	unsigned lcore_id = rte_lcore_id();
	uint32_t cache_size = mp->cache_size;

	/* cache is not enabled or single consumer */
	if (unlikely(cache_size == 0 || is_mc == 0 ||
		     n >= cache_size || lcore_id >= RTE_MAX_LCORE))
		goto ring_dequeue;

	cache = &mp->local_cache[lcore_id];
	cache_objs = cache->objs;

	/* Can this be satisfied from the cache? */
	if (cache->len < n) {
		/* No. Backfill the cache first, and then fill from it */
		uint32_t req = n + (cache_size - cache->len);

		/* How many do we require i.e. number to fill the cache + the request */
		ret = rte_ring_mc_dequeue_bulk(mp->ring, &cache->objs[cache->len], req);
		if (unlikely(ret < 0)) {
			/*
			 * In the offchance that we are buffer constrained,
			 * where we are not able to allocate cache + n, go to
			 * the ring directly. If that fails, we are truly out of
			 * buffers.
			 */
			goto ring_dequeue;
		}

		cache->len += req;
	}

	/* Now fill in the response ... */
	for (index = 0, len = cache->len - 1; index < n; ++index, len--, obj_table++)
		*obj_table = cache_objs[len];

	cache->len -= n;

	__MEMPOOL_STAT_ADD(mp, get_success, n);

	return 0;

ring_dequeue:
#endif /* RTE_MEMPOOL_CACHE_MAX_SIZE > 0 */

	/* get remaining objects from ring */
	if (is_mc)
		ret = rte_ring_mc_dequeue_bulk(mp->ring, obj_table, n);
	else
		ret = rte_ring_sc_dequeue_bulk(mp->ring, obj_table, n);

	if (ret < 0)
		__MEMPOOL_STAT_ADD(mp, get_fail, n);
	else
		__MEMPOOL_STAT_ADD(mp, get_success, n);

	return ret;
}

/**
 * Get several objects from the mempool (multi-consumers safe).
 *
 * If cache is enabled, objects will be retrieved first from cache,
 * subsequently from the common pool. Note that it can return -ENOENT when
 * the local cache and common pool are empty, even if cache from other
 * lcores are full.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_table
 *   A pointer to a table of void * pointers (objects) that will be filled.
 * @param n
 *   The number of objects to get from mempool to obj_table.
 * @return
 *   - 0: Success; objects taken.
 *   - -ENOENT: Not enough entries in the mempool; no object is retrieved.
 */
static inline int __attribute__((always_inline))
rte_mempool_mc_get_bulk(struct rte_mempool *mp, void **obj_table, unsigned n)
{
	int ret;
	ret = __mempool_get_bulk(mp, obj_table, n, 1);
	if (ret == 0)
		__mempool_check_cookies(mp, obj_table, n, 1);
	return ret;
}

/**
 * Get several objects from the mempool (NOT multi-consumers safe).
 *
 * If cache is enabled, objects will be retrieved first from cache,
 * subsequently from the common pool. Note that it can return -ENOENT when
 * the local cache and common pool are empty, even if cache from other
 * lcores are full.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_table
 *   A pointer to a table of void * pointers (objects) that will be filled.
 * @param n
 *   The number of objects to get from the mempool to obj_table.
 * @return
 *   - 0: Success; objects taken.
 *   - -ENOENT: Not enough entries in the mempool; no object is
 *     retrieved.
 */
static inline int __attribute__((always_inline))
rte_mempool_sc_get_bulk(struct rte_mempool *mp, void **obj_table, unsigned n)
{
	int ret;
	ret = __mempool_get_bulk(mp, obj_table, n, 0);
	if (ret == 0)
		__mempool_check_cookies(mp, obj_table, n, 1);
	return ret;
}

/**
 * Get several objects from the mempool.
 *
 * This function calls the multi-consumers or the single-consumer
 * version, depending on the default behaviour that was specified at
 * mempool creation time (see flags).
 *
 * If cache is enabled, objects will be retrieved first from cache,
 * subsequently from the common pool. Note that it can return -ENOENT when
 * the local cache and common pool are empty, even if cache from other
 * lcores are full.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_table
 *   A pointer to a table of void * pointers (objects) that will be filled.
 * @param n
 *   The number of objects to get from the mempool to obj_table.
 * @return
 *   - 0: Success; objects taken
 *   - -ENOENT: Not enough entries in the mempool; no object is retrieved.
 */
static inline int __attribute__((always_inline))
rte_mempool_get_bulk(struct rte_mempool *mp, void **obj_table, unsigned n)
{
	int ret;
	ret = __mempool_get_bulk(mp, obj_table, n,
				 !(mp->flags & MEMPOOL_F_SC_GET));
	if (ret == 0)
		__mempool_check_cookies(mp, obj_table, n, 1);
	return ret;
}

/**
 * Get one object from the mempool (multi-consumers safe).
 *
 * If cache is enabled, objects will be retrieved first from cache,
 * subsequently from the common pool. Note that it can return -ENOENT when
 * the local cache and common pool are empty, even if cache from other
 * lcores are full.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_p
 *   A pointer to a void * pointer (object) that will be filled.
 * @return
 *   - 0: Success; objects taken.
 *   - -ENOENT: Not enough entries in the mempool; no object is retrieved.
 */
static inline int __attribute__((always_inline))
rte_mempool_mc_get(struct rte_mempool *mp, void **obj_p)
{
	return rte_mempool_mc_get_bulk(mp, obj_p, 1);
}

/**
 * Get one object from the mempool (NOT multi-consumers safe).
 *
 * If cache is enabled, objects will be retrieved first from cache,
 * subsequently from the common pool. Note that it can return -ENOENT when
 * the local cache and common pool are empty, even if cache from other
 * lcores are full.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_p
 *   A pointer to a void * pointer (object) that will be filled.
 * @return
 *   - 0: Success; objects taken.
 *   - -ENOENT: Not enough entries in the mempool; no object is retrieved.
 */
static inline int __attribute__((always_inline))
rte_mempool_sc_get(struct rte_mempool *mp, void **obj_p)
{
	return rte_mempool_sc_get_bulk(mp, obj_p, 1);
}

/**
 * Get one object from the mempool.
 *
 * This function calls the multi-consumers or the single-consumer
 * version, depending on the default behavior that was specified at
 * mempool creation (see flags).
 *
 * If cache is enabled, objects will be retrieved first from cache,
 * subsequently from the common pool. Note that it can return -ENOENT when
 * the local cache and common pool are empty, even if cache from other
 * lcores are full.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param obj_p
 *   A pointer to a void * pointer (object) that will be filled.
 * @return
 *   - 0: Success; objects taken.
 *   - -ENOENT: Not enough entries in the mempool; no object is retrieved.
 */
static inline int __attribute__((always_inline))
rte_mempool_get(struct rte_mempool *mp, void **obj_p)
{
	return rte_mempool_get_bulk(mp, obj_p, 1);
}

/**
 * Return the number of entries in the mempool.
 *
 * When cache is enabled, this function has to browse the length of
 * all lcores, so it should not be used in a data path, but only for
 * debug purposes.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @return
 *   The number of entries in the mempool.
 */
unsigned rte_mempool_count(const struct rte_mempool *mp);

/**
 * Return the number of free entries in the mempool ring.
 * i.e. how many entries can be freed back to the mempool.
 *
 * NOTE: This corresponds to the number of elements *allocated* from the
 * memory pool, not the number of elements in the pool itself. To count
 * the number elements currently available in the pool, use "rte_mempool_count"
 *
 * When cache is enabled, this function has to browse the length of
 * all lcores, so it should not be used in a data path, but only for
 * debug purposes.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @return
 *   The number of free entries in the mempool.
 */
static inline unsigned
rte_mempool_free_count(const struct rte_mempool *mp)
{
	return mp->size - rte_mempool_count(mp);
}

/**
 * Test if the mempool is full.
 *
 * When cache is enabled, this function has to browse the length of all
 * lcores, so it should not be used in a data path, but only for debug
 * purposes.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @return
 *   - 1: The mempool is full.
 *   - 0: The mempool is not full.
 */
static inline int
rte_mempool_full(const struct rte_mempool *mp)
{
	return !!(rte_mempool_count(mp) == mp->size);
}

/**
 * Test if the mempool is empty.
 *
 * When cache is enabled, this function has to browse the length of all
 * lcores, so it should not be used in a data path, but only for debug
 * purposes.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @return
 *   - 1: The mempool is empty.
 *   - 0: The mempool is not empty.
 */
static inline int
rte_mempool_empty(const struct rte_mempool *mp)
{
	return !!(rte_mempool_count(mp) == 0);
}

/**
 * Return the physical address of elt, which is an element of the pool mp.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @param elt
 *   A pointer (virtual address) to the element of the pool.
 * @return
 *   The physical address of the elt element.
 */
static inline phys_addr_t
rte_mempool_virt2phy(const struct rte_mempool *mp, const void *elt)
{
	if (rte_eal_has_hugepages()) {
		uintptr_t off;

		off = (const char *)elt - (const char *)mp->elt_va_start;
		return mp->elt_pa[off >> mp->pg_shift] + (off & mp->pg_mask);
	} else {
		/*
		 * If huge pages are disabled, we cannot assume the
		 * memory region to be physically contiguous.
		 * Lookup for each element.
		 */
		return rte_mem_virt2phy(elt);
	}
}

/**
 * Check the consistency of mempool objects.
 *
 * Verify the coherency of fields in the mempool structure. Also check
 * that the cookies of mempool objects (even the ones that are not
 * present in pool) have a correct value. If not, a panic will occur.
 *
 * @param mp
 *   A pointer to the mempool structure.
 */
void rte_mempool_audit(const struct rte_mempool *mp);

/**
 * Return a pointer to the private data in an mempool structure.
 *
 * @param mp
 *   A pointer to the mempool structure.
 * @return
 *   A pointer to the private data.
 */
static inline void *rte_mempool_get_priv(struct rte_mempool *mp)
{
	return (char *)mp + MEMPOOL_HEADER_SIZE(mp, mp->pg_num);
}

/**
 * Dump the status of all mempools on the console
 *
 * @param f
 *   A pointer to a file for output
 */
void rte_mempool_list_dump(FILE *f);

/**
 * Search a mempool from its name
 *
 * @param name
 *   The name of the mempool.
 * @return
 *   The pointer to the mempool matching the name, or NULL if not found.
 *   NULL on error
 *   with rte_errno set appropriately. Possible rte_errno values include:
 *    - ENOENT - required entry not available to return.
 *
 */
struct rte_mempool *rte_mempool_lookup(const char *name);

/**
 * Get the header, trailer and total size of a mempool element.
 *
 * Given a desired size of the mempool element and mempool flags,
 * calculates header, trailer, body and total sizes of the mempool object.
 *
 * @param elt_size
 *   The size of each element.
 * @param flags
 *   The flags used for the mempool creation.
 *   Consult rte_mempool_create() for more information about possible values.
 *   The size of each element.
 * @param sz
 *   The calculated detailed size the mempool object. May be NULL.
 * @return
 *   Total size of the mempool object.
 */
uint32_t rte_mempool_calc_obj_size(uint32_t elt_size, uint32_t flags,
	struct rte_mempool_objsz *sz);

/**
 * Get the size of memory required to store mempool elements.
 *
 * Calculate the maximum amount of memory required to store given number
 * of objects. Assume that the memory buffer will be aligned at page
 * boundary.
 *
 * Note that if object size is bigger then page size, then it assumes
 * that pages are grouped in subsets of physically continuous pages big
 * enough to store at least one object.
 *
 * @param elt_num
 *   Number of elements.
 * @param elt_sz
 *   The size of each element.
 * @param pg_shift
 *   LOG2 of the physical pages size.
 * @return
 *   Required memory size aligned at page boundary.
 */
size_t rte_mempool_xmem_size(uint32_t elt_num, size_t elt_sz,
	uint32_t pg_shift);

/**
 * Get the size of memory required to store mempool elements.
 *
 * Calculate how much memory would be actually required with the given
 * memory footprint to store required number of objects.
 *
 * @param vaddr
 *   Virtual address of the externally allocated memory buffer.
 *   Will be used to store mempool objects.
 * @param elt_num
 *   Number of elements.
 * @param elt_sz
 *   The size of each element.
 * @param paddr
 *   Array of physical addresses of the pages that comprises given memory
 *   buffer.
 * @param pg_num
 *   Number of elements in the paddr array.
 * @param pg_shift
 *   LOG2 of the physical pages size.
 * @return
 *   On success, the number of bytes needed to store given number of
 *   objects, aligned to the given page size. If the provided memory
 *   buffer is too small, return a negative value whose absolute value
 *   is the actual number of elements that can be stored in that buffer.
 */
ssize_t rte_mempool_xmem_usage(void *vaddr, uint32_t elt_num, size_t elt_sz,
	const phys_addr_t paddr[], uint32_t pg_num, uint32_t pg_shift);

/**
 * Walk list of all memory pools
 *
 * @param func
 *   Iterator function
 * @param arg
 *   Argument passed to iterator
 */
void rte_mempool_walk(void (*func)(const struct rte_mempool *, void *arg),
		      void *arg);

#ifdef __cplusplus
}
#endif

#endif /* _RTE_MEMPOOL_H_ */