DPDK  24.07.0
rte_bitmap.h
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1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2014 Intel Corporation
3  */
4 
5 #ifndef __INCLUDE_RTE_BITMAP_H__
6 #define __INCLUDE_RTE_BITMAP_H__
7 
8 #ifdef __cplusplus
9 extern "C" {
10 #endif
11 
37 #include <string.h>
38 
39 #include <rte_common.h>
40 #include <rte_config.h>
41 #include <rte_debug.h>
42 #include <rte_memory.h>
43 #include <rte_branch_prediction.h>
44 #include <rte_prefetch.h>
45 
46 /* Slab */
47 #define RTE_BITMAP_SLAB_BIT_SIZE 64
48 #define RTE_BITMAP_SLAB_BIT_SIZE_LOG2 6
49 #define RTE_BITMAP_SLAB_BIT_MASK (RTE_BITMAP_SLAB_BIT_SIZE - 1)
50 
51 /* Cache line (CL) */
52 #define RTE_BITMAP_CL_BIT_SIZE (RTE_CACHE_LINE_SIZE * 8)
53 #define RTE_BITMAP_CL_BIT_SIZE_LOG2 (RTE_CACHE_LINE_SIZE_LOG2 + 3)
54 #define RTE_BITMAP_CL_BIT_MASK (RTE_BITMAP_CL_BIT_SIZE - 1)
55 
56 #define RTE_BITMAP_CL_SLAB_SIZE (RTE_BITMAP_CL_BIT_SIZE / RTE_BITMAP_SLAB_BIT_SIZE)
57 #define RTE_BITMAP_CL_SLAB_SIZE_LOG2 (RTE_BITMAP_CL_BIT_SIZE_LOG2 - RTE_BITMAP_SLAB_BIT_SIZE_LOG2)
58 #define RTE_BITMAP_CL_SLAB_MASK (RTE_BITMAP_CL_SLAB_SIZE - 1)
59 
61 struct rte_bitmap {
62  /* Context for array1 and array2 */
63  uint64_t *array1;
64  uint64_t *array2;
65  uint32_t array1_size;
66  uint32_t array2_size;
68  /* Context for the "scan next" operation */
69  uint32_t index1;
70  uint32_t offset1;
71  uint32_t index2;
72  uint32_t go2;
74  /* Storage space for array1 and array2 */
75  uint8_t memory[];
76 };
77 
78 static inline void
79 __rte_bitmap_index1_inc(struct rte_bitmap *bmp)
80 {
81  bmp->index1 = (bmp->index1 + 1) & (bmp->array1_size - 1);
82 }
83 
84 static inline uint64_t
85 __rte_bitmap_mask1_get(struct rte_bitmap *bmp)
86 {
87  return (~1llu) << bmp->offset1;
88 }
89 
90 static inline void
91 __rte_bitmap_index2_set(struct rte_bitmap *bmp)
92 {
93  bmp->index2 = (((bmp->index1 << RTE_BITMAP_SLAB_BIT_SIZE_LOG2) + bmp->offset1) << RTE_BITMAP_CL_SLAB_SIZE_LOG2);
94 }
95 
96 static inline uint32_t
97 __rte_bitmap_get_memory_footprint(uint32_t n_bits,
98  uint32_t *array1_byte_offset, uint32_t *array1_slabs,
99  uint32_t *array2_byte_offset, uint32_t *array2_slabs)
100 {
101  uint32_t n_slabs_context, n_slabs_array1, n_cache_lines_context_and_array1;
102  uint32_t n_cache_lines_array2;
103  uint32_t n_bytes_total;
104 
105  n_cache_lines_array2 = (n_bits + RTE_BITMAP_CL_BIT_SIZE - 1) / RTE_BITMAP_CL_BIT_SIZE;
106  n_slabs_array1 = (n_cache_lines_array2 + RTE_BITMAP_SLAB_BIT_SIZE - 1) / RTE_BITMAP_SLAB_BIT_SIZE;
107  n_slabs_array1 = rte_align32pow2(n_slabs_array1);
108  n_slabs_context = (sizeof(struct rte_bitmap) + (RTE_BITMAP_SLAB_BIT_SIZE / 8) - 1) / (RTE_BITMAP_SLAB_BIT_SIZE / 8);
109  n_cache_lines_context_and_array1 = (n_slabs_context + n_slabs_array1 + RTE_BITMAP_CL_SLAB_SIZE - 1) / RTE_BITMAP_CL_SLAB_SIZE;
110  n_bytes_total = (n_cache_lines_context_and_array1 + n_cache_lines_array2) * RTE_CACHE_LINE_SIZE;
111 
112  if (array1_byte_offset) {
113  *array1_byte_offset = n_slabs_context * (RTE_BITMAP_SLAB_BIT_SIZE / 8);
114  }
115  if (array1_slabs) {
116  *array1_slabs = n_slabs_array1;
117  }
118  if (array2_byte_offset) {
119  *array2_byte_offset = n_cache_lines_context_and_array1 * RTE_CACHE_LINE_SIZE;
120  }
121  if (array2_slabs) {
122  *array2_slabs = n_cache_lines_array2 * RTE_BITMAP_CL_SLAB_SIZE;
123  }
124 
125  return n_bytes_total;
126 }
127 
128 static inline void
129 __rte_bitmap_scan_init(struct rte_bitmap *bmp)
130 {
131  bmp->index1 = bmp->array1_size - 1;
132  bmp->offset1 = RTE_BITMAP_SLAB_BIT_SIZE - 1;
133  __rte_bitmap_index2_set(bmp);
134  bmp->index2 += RTE_BITMAP_CL_SLAB_SIZE;
135 
136  bmp->go2 = 0;
137 }
138 
147 static inline uint32_t
149  /* Check input arguments */
150  if (n_bits == 0) {
151  return 0;
152  }
153 
154  return __rte_bitmap_get_memory_footprint(n_bits, NULL, NULL, NULL, NULL);
155 }
156 
169 static inline struct rte_bitmap *
170 rte_bitmap_init(uint32_t n_bits, uint8_t *mem, uint32_t mem_size)
171 {
172  struct rte_bitmap *bmp;
173  uint32_t array1_byte_offset, array1_slabs, array2_byte_offset, array2_slabs;
174  uint32_t size;
175 
176  /* Check input arguments */
177  if (n_bits == 0) {
178  return NULL;
179  }
180 
181  if ((mem == NULL) || (((uintptr_t) mem) & RTE_CACHE_LINE_MASK)) {
182  return NULL;
183  }
184 
185  size = __rte_bitmap_get_memory_footprint(n_bits,
186  &array1_byte_offset, &array1_slabs,
187  &array2_byte_offset, &array2_slabs);
188  if (size > mem_size)
189  return NULL;
190 
191  /* Setup bitmap */
192  memset(mem, 0, size);
193  bmp = (struct rte_bitmap *) mem;
194 
195  bmp->array1 = (uint64_t *) &mem[array1_byte_offset];
196  bmp->array1_size = array1_slabs;
197  bmp->array2 = (uint64_t *) &mem[array2_byte_offset];
198  bmp->array2_size = array2_slabs;
199 
200  __rte_bitmap_scan_init(bmp);
201 
202  return bmp;
203 }
204 
215 static inline void
216 __rte_bitmap_clear_slab_overhead_bits(uint64_t *slabs, uint32_t slab_size,
217  uint32_t pos)
218 {
219  uint32_t i;
220  uint32_t index = pos / RTE_BITMAP_SLAB_BIT_SIZE;
221  uint32_t offset = pos & RTE_BITMAP_SLAB_BIT_MASK;
222 
223  if (offset) {
224  for (i = offset; i < RTE_BITMAP_SLAB_BIT_SIZE; i++)
225  slabs[index] &= ~(1llu << i);
226  index++;
227  }
228  if (index < slab_size)
229  memset(&slabs[index], 0, sizeof(slabs[0]) *
230  (slab_size - index));
231 }
232 
245 static inline struct rte_bitmap *
246 rte_bitmap_init_with_all_set(uint32_t n_bits, uint8_t *mem, uint32_t mem_size)
247 {
248  struct rte_bitmap *bmp;
249  uint32_t array1_byte_offset, array1_slabs;
250  uint32_t array2_byte_offset, array2_slabs;
251  uint32_t size;
252 
253  /* Check input arguments */
254  if (!n_bits || !mem || (((uintptr_t) mem) & RTE_CACHE_LINE_MASK))
255  return NULL;
256 
257  size = __rte_bitmap_get_memory_footprint(n_bits,
258  &array1_byte_offset, &array1_slabs,
259  &array2_byte_offset, &array2_slabs);
260  if (size < mem_size)
261  return NULL;
262 
263  /* Setup bitmap */
264  bmp = (struct rte_bitmap *) mem;
265  bmp->array1 = (uint64_t *) &mem[array1_byte_offset];
266  bmp->array1_size = array1_slabs;
267  bmp->array2 = (uint64_t *) &mem[array2_byte_offset];
268  bmp->array2_size = array2_slabs;
269 
270  __rte_bitmap_scan_init(bmp);
271 
272  memset(bmp->array1, 0xff, bmp->array1_size * sizeof(bmp->array1[0]));
273  memset(bmp->array2, 0xff, bmp->array2_size * sizeof(bmp->array2[0]));
274  /* Clear overhead bits. */
276  bmp->array2_size >> RTE_BITMAP_CL_SLAB_SIZE_LOG2);
278  n_bits);
279  return bmp;
280 }
281 
290 static inline int
292 {
293  /* Check input arguments */
294  if (bmp == NULL) {
295  return -1;
296  }
297 
298  return 0;
299 }
300 
307 static inline void
309 {
310  memset(bmp->array1, 0, bmp->array1_size * sizeof(uint64_t));
311  memset(bmp->array2, 0, bmp->array2_size * sizeof(uint64_t));
312  __rte_bitmap_scan_init(bmp);
313 }
314 
323 static inline void
324 rte_bitmap_prefetch0(struct rte_bitmap *bmp, uint32_t pos)
325 {
326  uint64_t *slab2;
327  uint32_t index2;
328 
329  index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
330  slab2 = bmp->array2 + index2;
331  rte_prefetch0((void *) slab2);
332 }
333 
344 static inline uint64_t
345 rte_bitmap_get(struct rte_bitmap *bmp, uint32_t pos)
346 {
347  uint64_t *slab2;
348  uint32_t index2, offset2;
349 
350  index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
351  offset2 = pos & RTE_BITMAP_SLAB_BIT_MASK;
352  slab2 = bmp->array2 + index2;
353  return (*slab2) & (1llu << offset2);
354 }
355 
364 static inline void
365 rte_bitmap_set(struct rte_bitmap *bmp, uint32_t pos)
366 {
367  uint64_t *slab1, *slab2;
368  uint32_t index1, index2, offset1, offset2;
369 
370  /* Set bit in array2 slab and set bit in array1 slab */
371  index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
372  offset2 = pos & RTE_BITMAP_SLAB_BIT_MASK;
373  index1 = pos >> (RTE_BITMAP_SLAB_BIT_SIZE_LOG2 + RTE_BITMAP_CL_BIT_SIZE_LOG2);
374  offset1 = (pos >> RTE_BITMAP_CL_BIT_SIZE_LOG2) & RTE_BITMAP_SLAB_BIT_MASK;
375  slab2 = bmp->array2 + index2;
376  slab1 = bmp->array1 + index1;
377 
378  *slab2 |= 1llu << offset2;
379  *slab1 |= 1llu << offset1;
380 }
381 
392 static inline void
393 rte_bitmap_set_slab(struct rte_bitmap *bmp, uint32_t pos, uint64_t slab)
394 {
395  uint64_t *slab1, *slab2;
396  uint32_t index1, index2, offset1;
397 
398  /* Set bits in array2 slab and set bit in array1 slab */
399  index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
400  index1 = pos >> (RTE_BITMAP_SLAB_BIT_SIZE_LOG2 + RTE_BITMAP_CL_BIT_SIZE_LOG2);
401  offset1 = (pos >> RTE_BITMAP_CL_BIT_SIZE_LOG2) & RTE_BITMAP_SLAB_BIT_MASK;
402  slab2 = bmp->array2 + index2;
403  slab1 = bmp->array1 + index1;
404 
405  *slab2 |= slab;
406  *slab1 |= 1llu << offset1;
407 }
408 
409 #if RTE_BITMAP_CL_SLAB_SIZE == 8
410 static inline uint64_t
411 __rte_bitmap_line_not_empty(uint64_t *slab2)
412 {
413  uint64_t v1, v2, v3, v4;
414 
415  v1 = slab2[0] | slab2[1];
416  v2 = slab2[2] | slab2[3];
417  v3 = slab2[4] | slab2[5];
418  v4 = slab2[6] | slab2[7];
419  v1 |= v2;
420  v3 |= v4;
421 
422  return v1 | v3;
423 }
424 
425 #elif RTE_BITMAP_CL_SLAB_SIZE == 16
426 static inline uint64_t
427 __rte_bitmap_line_not_empty(uint64_t *slab2)
428 {
429  uint64_t v1, v2, v3, v4, v5, v6, v7, v8;
430 
431  v1 = slab2[0] | slab2[1];
432  v2 = slab2[2] | slab2[3];
433  v3 = slab2[4] | slab2[5];
434  v4 = slab2[6] | slab2[7];
435  v5 = slab2[8] | slab2[9];
436  v6 = slab2[10] | slab2[11];
437  v7 = slab2[12] | slab2[13];
438  v8 = slab2[14] | slab2[15];
439  v1 |= v2;
440  v3 |= v4;
441  v5 |= v6;
442  v7 |= v8;
443 
444  return v1 | v3 | v5 | v7;
445 }
446 
447 #endif /* RTE_BITMAP_CL_SLAB_SIZE */
448 
457 static inline void
458 rte_bitmap_clear(struct rte_bitmap *bmp, uint32_t pos)
459 {
460  uint64_t *slab1, *slab2;
461  uint32_t index1, index2, offset1, offset2;
462 
463  /* Clear bit in array2 slab */
464  index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
465  offset2 = pos & RTE_BITMAP_SLAB_BIT_MASK;
466  slab2 = bmp->array2 + index2;
467 
468  /* Return if array2 slab is not all-zeros */
469  *slab2 &= ~(1llu << offset2);
470  if (*slab2){
471  return;
472  }
473 
474  /* Check the entire cache line of array2 for all-zeros */
475  index2 &= ~ RTE_BITMAP_CL_SLAB_MASK;
476  slab2 = bmp->array2 + index2;
477  if (__rte_bitmap_line_not_empty(slab2)) {
478  return;
479  }
480 
481  /* The array2 cache line is all-zeros, so clear bit in array1 slab */
482  index1 = pos >> (RTE_BITMAP_SLAB_BIT_SIZE_LOG2 + RTE_BITMAP_CL_BIT_SIZE_LOG2);
483  offset1 = (pos >> RTE_BITMAP_CL_BIT_SIZE_LOG2) & RTE_BITMAP_SLAB_BIT_MASK;
484  slab1 = bmp->array1 + index1;
485  *slab1 &= ~(1llu << offset1);
486 
487  return;
488 }
489 
490 static inline int
491 __rte_bitmap_scan_search(struct rte_bitmap *bmp)
492 {
493  uint64_t value1;
494  uint32_t i;
495 
496  /* Check current array1 slab */
497  value1 = bmp->array1[bmp->index1];
498  value1 &= __rte_bitmap_mask1_get(bmp);
499 
500  if (rte_bsf64_safe(value1, &bmp->offset1))
501  return 1;
502 
503  __rte_bitmap_index1_inc(bmp);
504  bmp->offset1 = 0;
505 
506  /* Look for another array1 slab */
507  for (i = 0; i < bmp->array1_size; i ++, __rte_bitmap_index1_inc(bmp)) {
508  value1 = bmp->array1[bmp->index1];
509 
510  if (rte_bsf64_safe(value1, &bmp->offset1))
511  return 1;
512  }
513 
514  return 0;
515 }
516 
517 static inline void
518 __rte_bitmap_scan_read_init(struct rte_bitmap *bmp)
519 {
520  __rte_bitmap_index2_set(bmp);
521  bmp->go2 = 1;
522  rte_prefetch1((void *)(bmp->array2 + bmp->index2 + 8));
523 }
524 
525 static inline int
526 __rte_bitmap_scan_read(struct rte_bitmap *bmp, uint32_t *pos, uint64_t *slab)
527 {
528  uint64_t *slab2;
529 
530  slab2 = bmp->array2 + bmp->index2;
531  for ( ; bmp->go2 ; bmp->index2 ++, slab2 ++, bmp->go2 = bmp->index2 & RTE_BITMAP_CL_SLAB_MASK) {
532  if (*slab2) {
533  *pos = bmp->index2 << RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
534  *slab = *slab2;
535 
536  bmp->index2 ++;
537  slab2 ++;
538  bmp->go2 = bmp->index2 & RTE_BITMAP_CL_SLAB_MASK;
539  return 1;
540  }
541  }
542 
543  return 0;
544 }
545 
566 static inline int
567 rte_bitmap_scan(struct rte_bitmap *bmp, uint32_t *pos, uint64_t *slab)
568 {
569  /* Return data from current array2 line if available */
570  if (__rte_bitmap_scan_read(bmp, pos, slab)) {
571  return 1;
572  }
573 
574  /* Look for non-empty array2 line */
575  if (__rte_bitmap_scan_search(bmp)) {
576  __rte_bitmap_scan_read_init(bmp);
577  __rte_bitmap_scan_read(bmp, pos, slab);
578  return 1;
579  }
580 
581  /* Empty bitmap */
582  return 0;
583 }
584 
585 #ifdef __cplusplus
586 }
587 #endif
588 
589 #endif /* __INCLUDE_RTE_BITMAP_H__ */
static int rte_bitmap_free(struct rte_bitmap *bmp)
Definition: rte_bitmap.h:291
static void rte_bitmap_set_slab(struct rte_bitmap *bmp, uint32_t pos, uint64_t slab)
Definition: rte_bitmap.h:393
static void rte_bitmap_set(struct rte_bitmap *bmp, uint32_t pos)
Definition: rte_bitmap.h:365
static void rte_bitmap_reset(struct rte_bitmap *bmp)
Definition: rte_bitmap.h:308
static struct rte_bitmap * rte_bitmap_init_with_all_set(uint32_t n_bits, uint8_t *mem, uint32_t mem_size)
Definition: rte_bitmap.h:246
static void __rte_bitmap_clear_slab_overhead_bits(uint64_t *slabs, uint32_t slab_size, uint32_t pos)
Definition: rte_bitmap.h:216
static void rte_bitmap_clear(struct rte_bitmap *bmp, uint32_t pos)
Definition: rte_bitmap.h:458
static struct rte_bitmap * rte_bitmap_init(uint32_t n_bits, uint8_t *mem, uint32_t mem_size)
Definition: rte_bitmap.h:170
uint32_t array1_size
Definition: rte_bitmap.h:65
uint64_t * array1
Definition: rte_bitmap.h:63
static uint32_t rte_align32pow2(uint32_t x)
Definition: rte_bitops.h:687
static uint32_t rte_bitmap_get_memory_footprint(uint32_t n_bits)
Definition: rte_bitmap.h:148
uint64_t * array2
Definition: rte_bitmap.h:64
static int rte_bsf64_safe(uint64_t v, uint32_t *pos)
Definition: rte_bitops.h:614
static uint64_t rte_bitmap_get(struct rte_bitmap *bmp, uint32_t pos)
Definition: rte_bitmap.h:345
uint32_t index2
Definition: rte_bitmap.h:71
static void rte_bitmap_prefetch0(struct rte_bitmap *bmp, uint32_t pos)
Definition: rte_bitmap.h:324
uint32_t index1
Definition: rte_bitmap.h:69
static void rte_prefetch1(const volatile void *p)
#define RTE_CACHE_LINE_MASK
Definition: rte_common.h:550
static int rte_bitmap_scan(struct rte_bitmap *bmp, uint32_t *pos, uint64_t *slab)
Definition: rte_bitmap.h:567
uint32_t go2
Definition: rte_bitmap.h:72
uint32_t array2_size
Definition: rte_bitmap.h:66
uint32_t offset1
Definition: rte_bitmap.h:70
static void rte_prefetch0(const volatile void *p)