aboutsummaryrefslogtreecommitdiffstats
path: root/src/svm/svm_fifo_segment.c
blob: 8a8bd4aa7ffcb71990f7d4a67747f540df36cd43 (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
/*
 * Copyright (c) 2016-2019 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <svm/svm_fifo_segment.h>

static void
fifo_init_for_segment (svm_fifo_segment_header_t * fsh, u8 * fifo_space,
		       u32 size, u32 freelist_index)
{
  svm_fifo_t *f;

  f = (svm_fifo_t *) fifo_space;
  f->freelist_index = freelist_index;
  f->default_chunk.start_byte = 0;
  f->default_chunk.length = size;
  f->default_chunk.next = f->start_chunk = f->end_chunk = &f->default_chunk;
  f->head_chunk = f->tail_chunk = f->ooo_enq = f->ooo_deq = f->start_chunk;
  f->next = fsh->free_fifos[freelist_index];
  fsh->free_fifos[freelist_index] = f;
}

static void
allocate_new_fifo_chunk (svm_fifo_segment_header_t * fsh,
			 u32 data_size_in_bytes, int chunk_size)
{
  int freelist_index;
  u32 size;
  u8 *fifo_space;
  u32 rounded_data_size;
  svm_fifo_t *f;
  int i;

  rounded_data_size = (1 << (max_log2 (data_size_in_bytes)));
  freelist_index = max_log2 (rounded_data_size)
    - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);

  /* Calculate space requirement $$$ round-up data_size_in_bytes */
  size = (sizeof (*f) + rounded_data_size) * chunk_size;

  /* Allocate fifo space. May fail. */
  fifo_space = clib_mem_alloc_aligned_at_offset
    (size, CLIB_CACHE_LINE_BYTES, 0 /* align_offset */ ,
     0 /* os_out_of_memory */ );

  /* Out of space.. */
  if (fifo_space == 0)
    return;

  /* Carve fifo space */
  for (i = 0; i < chunk_size; i++)
    {
      fifo_init_for_segment (fsh, fifo_space, rounded_data_size,
			     freelist_index);
      fifo_space += sizeof (*f) + rounded_data_size;
    }
}

/**
 * Pre-allocates fifo pairs in fifo segment
 *
 * The number of fifos pre-allocated is the minimum of the requested number
 * of pairs and the maximum number that fit within the segment. If the maximum
 * is hit, the number of fifo pairs requested is updated by subtracting the
 * number of fifos that have been successfully allocated.
 */
void
svm_fifo_segment_preallocate_fifo_pairs (svm_fifo_segment_private_t * s,
					 u32 rx_fifo_size, u32 tx_fifo_size,
					 u32 * n_fifo_pairs)
{
  u32 rx_rounded_data_size, tx_rounded_data_size, pair_size;
  u32 rx_fifos_size, tx_fifos_size, pairs_to_allocate;
  int rx_freelist_index, tx_freelist_index;
  ssvm_shared_header_t *sh = s->ssvm.sh;
  svm_fifo_segment_header_t *fsh = s->h;
  u8 *rx_fifo_space, *tx_fifo_space;
  uword space_available;
  void *oldheap;
  svm_fifo_t *f;
  int i;

  /* Parameter check */
  if (rx_fifo_size == 0 || tx_fifo_size == 0 || *n_fifo_pairs == 0)
    return;

  if (rx_fifo_size < FIFO_SEGMENT_MIN_FIFO_SIZE ||
      rx_fifo_size > FIFO_SEGMENT_MAX_FIFO_SIZE)
    {
      clib_warning ("rx fifo_size out of range %d", rx_fifo_size);
      return;
    }

  if (tx_fifo_size < FIFO_SEGMENT_MIN_FIFO_SIZE ||
      tx_fifo_size > FIFO_SEGMENT_MAX_FIFO_SIZE)
    {
      clib_warning ("tx fifo_size out of range %d", rx_fifo_size);
      return;
    }

  rx_rounded_data_size = (1 << (max_log2 (rx_fifo_size)));
  rx_freelist_index = max_log2 (rx_fifo_size)
    - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);
  tx_rounded_data_size = (1 << (max_log2 (tx_fifo_size)));
  tx_freelist_index = max_log2 (tx_fifo_size)
    - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);

  /* Calculate space requirements */
  pair_size = 2 * sizeof (*f) + rx_rounded_data_size + tx_rounded_data_size;
#if USE_DLMALLOC == 0
  space_available = s->ssvm.ssvm_size - mheap_bytes (sh->heap);
#else
  space_available = s->ssvm.ssvm_size - mspace_usable_size (sh->heap);
#endif

  pairs_to_allocate = clib_min (space_available / pair_size, *n_fifo_pairs);
  rx_fifos_size = (sizeof (*f) + rx_rounded_data_size) * pairs_to_allocate;
  tx_fifos_size = (sizeof (*f) + tx_rounded_data_size) * pairs_to_allocate;

  vec_validate_init_empty (fsh->free_fifos,
			   clib_max (rx_freelist_index, tx_freelist_index),
			   0);

  oldheap = ssvm_push_heap (sh);
  /* Allocate rx fifo space. May fail. */
  rx_fifo_space = clib_mem_alloc_aligned_at_offset
    (rx_fifos_size, CLIB_CACHE_LINE_BYTES, 0 /* align_offset */ ,
     0 /* os_out_of_memory */ );

  /* Same for TX */
  tx_fifo_space = clib_mem_alloc_aligned_at_offset
    (tx_fifos_size, CLIB_CACHE_LINE_BYTES, 0 /* align_offset */ ,
     0 /* os_out_of_memory */ );

  /* Make sure it worked. Clean up if it didn't... */
  if (rx_fifo_space == 0 || tx_fifo_space == 0)
    {
      if (rx_fifo_space)
	clib_mem_free (rx_fifo_space);
      else
	clib_warning ("rx fifo preallocation failure: size %d npairs %d",
		      rx_fifo_size, *n_fifo_pairs);

      if (tx_fifo_space)
	clib_mem_free (tx_fifo_space);
      else
	clib_warning ("tx fifo preallocation failure: size %d nfifos %d",
		      tx_fifo_size, *n_fifo_pairs);
      ssvm_pop_heap (oldheap);
      return;
    }

  /* Carve rx fifo space */
  for (i = 0; i < pairs_to_allocate; i++)
    {
      fifo_init_for_segment (fsh, rx_fifo_space, rx_rounded_data_size,
			     rx_freelist_index);
      rx_fifo_space += sizeof (*f) + rx_rounded_data_size;
    }
  /* Carve tx fifo space */
  for (i = 0; i < pairs_to_allocate; i++)
    {
      fifo_init_for_segment (fsh, tx_fifo_space, tx_rounded_data_size,
			     tx_freelist_index);
      tx_fifo_space += sizeof (*f) + tx_rounded_data_size;
    }

  /* Account for the pairs allocated */
  *n_fifo_pairs -= pairs_to_allocate;
  ssvm_pop_heap (oldheap);
}

/**
 * Initialize svm fifo segment shared header
 */
int
svm_fifo_segment_init (svm_fifo_segment_private_t * s)
{
  svm_fifo_segment_header_t *fsh;
  ssvm_shared_header_t *sh;
  void *oldheap;

  sh = s->ssvm.sh;
  oldheap = ssvm_push_heap (sh);

  fsh = clib_mem_alloc (sizeof (*fsh));
  clib_memset (fsh, 0, sizeof (*fsh));
  s->h = sh->opaque[0] = fsh;

  ssvm_pop_heap (oldheap);

  sh->ready = 1;
  return (0);
}

/**
 * Create an svm fifo segment and initialize as master
 */
int
svm_fifo_segment_create (svm_fifo_segment_main_t * sm,
			 svm_fifo_segment_create_args_t * a)
{
  svm_fifo_segment_private_t *s;
  int rv;

  /* Allocate a fresh segment */
  pool_get (sm->segments, s);
  clib_memset (s, 0, sizeof (*s));

  s->ssvm.ssvm_size = a->segment_size;
  s->ssvm.i_am_master = 1;
  s->ssvm.my_pid = getpid ();
  s->ssvm.name = format (0, "%s%c", a->segment_name, 0);
  s->ssvm.requested_va = sm->next_baseva;

  if ((rv = ssvm_master_init (&s->ssvm, a->segment_type)))
    {
      pool_put (sm->segments, s);
      return (rv);
    }

  /* Note: requested_va updated due to seg base addr randomization */
  sm->next_baseva = s->ssvm.sh->ssvm_va + a->segment_size;

  svm_fifo_segment_init (s);
  vec_add1 (a->new_segment_indices, s - sm->segments);
  return (0);
}

/**
 * Create an svm fifo segment in process-private memory
 */
int
svm_fifo_segment_create_process_private (svm_fifo_segment_main_t * sm,
					 svm_fifo_segment_create_args_t * a)
{
  svm_fifo_segment_private_t *s;
  ssvm_shared_header_t *sh;
  u32 rnd_size = 0;
  u8 *heap;
  u32 pagesize = clib_mem_get_page_size ();

  pool_get (sm->segments, s);
  clib_memset (s, 0, sizeof (*s));

  rnd_size = (a->segment_size + (pagesize - 1)) & ~pagesize;

#if USE_DLMALLOC == 0
  heap = mheap_alloc (0, rnd_size);
  if (heap == 0)
    {
      clib_unix_warning ("mheap alloc");
      pool_put (sm->segments, s);
      return -1;
    }
  {
    mheap_t *heap_header;
    heap_header = mheap_header (heap);
    heap_header->flags |= MHEAP_FLAG_THREAD_SAFE;
  }
#else
  heap = create_mspace (rnd_size, 1 /* locked */ );
#endif

  s->ssvm.ssvm_size = rnd_size;
  s->ssvm.i_am_master = 1;
  s->ssvm.my_pid = getpid ();
  s->ssvm.name = format (0, "%s%c", a->segment_name, 0);
  s->ssvm.requested_va = ~0;

  /* Allocate a [sic] shared memory header, in process memory... */
  sh = clib_mem_alloc_aligned (sizeof (*sh), CLIB_CACHE_LINE_BYTES);
  s->ssvm.sh = sh;

  clib_memset (sh, 0, sizeof (*sh));
  sh->heap = heap;

  svm_fifo_segment_init (s);
  vec_add1 (a->new_segment_indices, s - sm->segments);

  return (0);
}

/**
 * Attach as slave to an svm fifo segment
 */
int
svm_fifo_segment_attach (svm_fifo_segment_main_t * sm,
			 svm_fifo_segment_create_args_t * a)
{
  svm_fifo_segment_private_t *s;
  int rv;

  /* Allocate a fresh segment */
  pool_get (sm->segments, s);
  clib_memset (s, 0, sizeof (*s));

  s->ssvm.ssvm_size = a->segment_size;
  s->ssvm.my_pid = getpid ();
  s->ssvm.name = format (0, "%s%c", a->segment_name, 0);
  s->ssvm.requested_va = sm->next_baseva;
  if (a->segment_type == SSVM_SEGMENT_MEMFD)
    s->ssvm.fd = a->memfd_fd;
  else
    s->ssvm.attach_timeout = sm->timeout_in_seconds;

  if ((rv = ssvm_slave_init (&s->ssvm, a->segment_type)))
    {
      _vec_len (s) = vec_len (s) - 1;
      return (rv);
    }

  /* Fish the segment header */
  s->h = s->ssvm.sh->opaque[0];

  vec_add1 (a->new_segment_indices, s - sm->segments);
  return (0);
}

void
svm_fifo_segment_delete (svm_fifo_segment_main_t * sm,
			 svm_fifo_segment_private_t * s)
{
  ssvm_delete (&s->ssvm);
  clib_memset (s, 0xfe, sizeof (*s));
  pool_put (sm->segments, s);
}

/**
 * Allocate fifo in svm segment
 */
svm_fifo_t *
svm_fifo_segment_alloc_fifo (svm_fifo_segment_private_t * fs,
			     u32 data_size_in_bytes,
			     svm_fifo_segment_freelist_t list_index)
{
  ssvm_shared_header_t *sh;
  svm_fifo_segment_header_t *fsh;
  svm_fifo_t *f = 0;
  void *oldheap;
  int freelist_index;

  /*
   * 4K minimum. It's not likely that anything good will happen
   * with a smaller FIFO.
   */
  if (data_size_in_bytes < FIFO_SEGMENT_MIN_FIFO_SIZE ||
      data_size_in_bytes > FIFO_SEGMENT_MAX_FIFO_SIZE)
    {
      clib_warning ("fifo size out of range %d", data_size_in_bytes);
      return 0;
    }

  freelist_index = max_log2 (data_size_in_bytes)
    - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);

  sh = fs->ssvm.sh;
  ssvm_lock_non_recursive (sh, 1);
  fsh = (svm_fifo_segment_header_t *) sh->opaque[0];

  switch (list_index)
    {
    case FIFO_SEGMENT_RX_FREELIST:
    case FIFO_SEGMENT_TX_FREELIST:
      vec_validate_init_empty (fsh->free_fifos, freelist_index, 0);
      f = fsh->free_fifos[freelist_index];
      if (PREDICT_FALSE (!f))
	{
	  oldheap = ssvm_push_heap (sh);
	  allocate_new_fifo_chunk (fsh, data_size_in_bytes,
				   FIFO_SEGMENT_ALLOC_CHUNK_SIZE);
	  ssvm_pop_heap (oldheap);
	  f = fsh->free_fifos[freelist_index];
	}
      if (PREDICT_TRUE (f != 0))
	{
	  fsh->free_fifos[freelist_index] = f->next;
	  /* (re)initialize the fifo, as in svm_fifo_create */
	  clib_memset (f, 0, sizeof (*f));
	  svm_fifo_init (f, data_size_in_bytes);
	  goto found;
	}
      break;
    case FIFO_SEGMENT_FREELIST_NONE:
      break;

    default:
      clib_warning ("ignore bogus freelist %d", list_index);
      break;
    }

  /* Catch all that allocates just one fifo. Note: this can fail,
   * in which case: create another segment */
  oldheap = ssvm_push_heap (sh);
  f = svm_fifo_create (data_size_in_bytes);
  ssvm_pop_heap (oldheap);
  if (PREDICT_FALSE (f == 0))
    goto done;
  f->freelist_index = freelist_index;

found:
  /* If rx_freelist add to active fifos list. When cleaning up segment,
   * we need a list of active sessions that should be disconnected. Since
   * both rx and tx fifos keep pointers to the session, it's enough to track
   * only one. */
  if (list_index == FIFO_SEGMENT_RX_FREELIST)
    {
      if (fsh->fifos)
	{
	  fsh->fifos->prev = f;
	  f->next = fsh->fifos;
	}
      fsh->fifos = f;
    }
  fsh->n_active_fifos++;

done:
  ssvm_unlock_non_recursive (sh);
  return (f);
}

void
svm_fifo_segment_free_fifo (svm_fifo_segment_private_t * s, svm_fifo_t * f,
			    svm_fifo_segment_freelist_t list_index)
{
  ssvm_shared_header_t *sh;
  svm_fifo_segment_header_t *fsh;
  int freelist_index;

  ASSERT (f->refcnt > 0);

  if (--f->refcnt > 0)
    return;

  sh = s->ssvm.sh;
  fsh = (svm_fifo_segment_header_t *) sh->opaque[0];

  freelist_index = f->freelist_index;

  ASSERT (freelist_index < vec_len (fsh->free_fifos));

  ssvm_lock_non_recursive (sh, 2);

  switch (list_index)
    {
    case FIFO_SEGMENT_RX_FREELIST:
      /* Remove from active list */
      if (f->prev)
	f->prev->next = f->next;
      else
	fsh->fifos = f->next;
      if (f->next)
	f->next->prev = f->prev;
      /* Fall through: we add only rx fifos to active pool */
    case FIFO_SEGMENT_TX_FREELIST:
      /* Add to free list */
      f->next = fsh->free_fifos[freelist_index];
      f->prev = 0;
      fsh->free_fifos[freelist_index] = f;
      break;
    case FIFO_SEGMENT_FREELIST_NONE:
      break;

    default:
      clib_warning ("ignore bogus freelist %d", list_index);
      break;
    }

  if (CLIB_DEBUG)
    {
      f->master_session_index = ~0;
      f->master_thread_index = ~0;
    }

  fsh->n_active_fifos--;
  ssvm_unlock_non_recursive (sh);
}

void
svm_fifo_segment_main_init (svm_fifo_segment_main_t * sm, u64 baseva,
			    u32 timeout_in_seconds)
{
  sm->next_baseva = baseva;
  sm->timeout_in_seconds = timeout_in_seconds;
}

u32
svm_fifo_segment_index (svm_fifo_segment_main_t * sm,
			svm_fifo_segment_private_t * s)
{
  return s - sm->segments;
}

/**
 * Retrieve svm segments pool. Used only for debug purposes.
 */
svm_fifo_segment_private_t *
svm_fifo_segment_segments_pool (svm_fifo_segment_main_t * sm)
{
  return sm->segments;
}

/**
 * Get number of active fifos
 */
u32
svm_fifo_segment_num_fifos (svm_fifo_segment_private_t * fifo_segment)
{
  return fifo_segment->h->n_active_fifos;
}

u32
svm_fifo_segment_num_free_fifos (svm_fifo_segment_private_t * fifo_segment,
				 u32 fifo_size_in_bytes)
{
  ssvm_shared_header_t *sh;
  svm_fifo_segment_header_t *fsh;
  svm_fifo_t *f;
  int i;
  u32 count = 0, rounded_data_size, freelist_index;

  sh = fifo_segment->ssvm.sh;
  fsh = (svm_fifo_segment_header_t *) sh->opaque[0];

  /* Count all free fifos? */
  if (fifo_size_in_bytes == ~0)
    {
      for (i = 0; i < vec_len (fsh->free_fifos); i++)
	{
	  f = fsh->free_fifos[i];
	  if (f == 0)
	    continue;

	  while (f)
	    {
	      f = f->next;
	      count++;
	    }
	}
      return count;
    }

  rounded_data_size = (1 << (max_log2 (fifo_size_in_bytes)));
  freelist_index = max_log2 (rounded_data_size)
    - max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE);

  if (freelist_index >= vec_len (fsh->free_fifos))
    return 0;

  f = fsh->free_fifos[freelist_index];
  if (f == 0)
    return 0;

  while (f)
    {
      f = f->next;
      count++;
    }
  return count;
}

void
svm_fifo_segment_info (svm_fifo_segment_private_t * seg, char **address,
		       size_t * size)
{
  if (ssvm_type (&seg->ssvm) == SSVM_SEGMENT_PRIVATE)
    {
#if USE_DLMALLOC == 0
      mheap_t *heap_header;

      *address = pointer_to_uword (seg->ssvm.sh->heap);
      heap_header = mheap_header (seg->ssvm.sh->heap);
      *size = heap_header->max_size;
#else
      mspace_get_address_and_size (seg->ssvm.sh->heap, address, size);
#endif
    }
  else
    {
      *address = (char *) seg->ssvm.sh->ssvm_va;
      *size = seg->ssvm.ssvm_size;
    }
}

void *
svm_fifo_segment_heap (svm_fifo_segment_private_t * seg)
{
  return seg->ssvm.sh->heap;
}

u8 *
format_svm_fifo_segment_type (u8 * s, va_list * args)
{
  svm_fifo_segment_private_t *sp;
  sp = va_arg (*args, svm_fifo_segment_private_t *);
  ssvm_segment_type_t st = ssvm_type (&sp->ssvm);

  if (st == SSVM_SEGMENT_PRIVATE)
    s = format (s, "%s", "private-heap");
  else if (st == SSVM_SEGMENT_MEMFD)
    s = format (s, "%s", "memfd");
  else if (st == SSVM_SEGMENT_SHM)
    s = format (s, "%s", "shm");
  else
    s = format (s, "%s", "unknown");
  return s;
}

/**
 * Segment format function
 */
u8 *
format_svm_fifo_segment (u8 * s, va_list * args)
{
  svm_fifo_segment_private_t *sp
    = va_arg (*args, svm_fifo_segment_private_t *);
  int verbose __attribute__ ((unused)) = va_arg (*args, int);
  svm_fifo_segment_header_t *fsh = sp->h;
  u32 count, indent;
  svm_fifo_t *f;
  int i;

  indent = format_get_indent (s) + 2;
#if USE_DLMALLOC == 0
  s = format (s, "%U segment heap: %U\n", format_white_space, indent,
	      format_mheap, svm_fifo_segment_heap (sp), verbose);
  s = format (s, "%U segment has %u active fifos\n",
	      format_white_space, indent, svm_fifo_segment_num_fifos (sp));
#endif

  for (i = 0; i < vec_len (fsh->free_fifos); i++)
    {
      f = fsh->free_fifos[i];
      if (f == 0)
	continue;
      count = 0;
      while (f)
	{
	  f = f->next;
	  count++;
	}

      s = format (s, "%U%-5u Kb: %u free",
		  format_white_space, indent + 2,
		  1 << (i + max_log2 (FIFO_SEGMENT_MIN_FIFO_SIZE) - 10),
		  count);
    }
  return s;
}

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */