aboutsummaryrefslogtreecommitdiffstats
path: root/src/vnet/session/session.h
blob: 0ccd3fb13bdc9f832e0aba870f89b90eebe4bca1 (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
/*
 * Copyright (c) 2017-2019 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.
 */
#ifndef __included_session_h__
#define __included_session_h__

#include <vppinfra/llist.h>
#include <vnet/session/session_types.h>
#include <vnet/session/session_lookup.h>
#include <vnet/session/session_debug.h>
#include <svm/message_queue.h>
#include <svm/fifo_segment.h>
#include <vlib/dma/dma.h>

#define foreach_session_input_error                                    	\
_(NO_SESSION, "No session drops")                                       \
_(NO_LISTENER, "No listener for dst port drops")                        \
_(ENQUEUED, "Packets pushed into rx fifo")                              \
_(NOT_READY, "Session not ready packets")                               \
_(FIFO_FULL, "Packets dropped for lack of rx fifo space")               \
_(EVENT_FIFO_FULL, "Events not sent for lack of event fifo space")      \
_(API_QUEUE_FULL, "Sessions not created for lack of API queue space")   \

typedef enum
{
#define _(sym,str) SESSION_ERROR_##sym,
  foreach_session_input_error
#undef _
    SESSION_N_ERROR,
} session_input_error_t;

typedef struct session_tx_context_
{
  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
  session_t *s;
  transport_proto_vft_t *transport_vft;
  transport_connection_t *tc;
  transport_send_params_t sp;
  u32 max_dequeue;
  u32 left_to_snd;
  u32 max_len_to_snd;
  u16 deq_per_first_buf;
  u16 deq_per_buf;
  u16 n_segs_per_evt;
  u16 n_bufs_needed;
  u8 n_bufs_per_seg;
    CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
  session_dgram_hdr_t hdr;

  /** Vector of tx buffer free lists */
  u32 *tx_buffers;
  vlib_buffer_t **transport_pending_bufs;
} session_tx_context_t;

typedef struct session_evt_elt
{
  clib_llist_anchor_t evt_list;
  session_event_t evt;
} session_evt_elt_t;

typedef struct session_ctrl_evt_data_
{
  u8 data[SESSION_CTRL_MSG_MAX_SIZE];
} session_evt_ctrl_data_t;

typedef enum session_wrk_state_
{
  SESSION_WRK_POLLING,
  SESSION_WRK_INTERRUPT,
  SESSION_WRK_IDLE,
} __clib_packed session_wrk_state_t;

typedef enum session_wrk_flags_
{
  SESSION_WRK_F_ADAPTIVE = 1 << 0,
} __clib_packed session_wrk_flag_t;

#define DMA_TRANS_SIZE 1024
typedef struct
{
  u32 *pending_tx_buffers;
  u16 *pending_tx_nexts;
} session_dma_transfer;

typedef struct session_worker_
{
  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);

  /** Worker session pool */
  session_t *sessions;

  /** vpp event message queue for worker */
  svm_msg_q_t *vpp_event_queue;

  /** vlib_time_now last time around the track */
  clib_time_type_t last_vlib_time;

  /** vlib_time_now rounded to us precision and as u64 */
  clib_us_time_t last_vlib_us_time;

  /** Convenience pointer to this worker's vlib_main */
  vlib_main_t *vm;

  /** Per-proto vector of sessions to enqueue */
  u32 **session_to_enqueue;

  /** Timerfd used to periodically signal wrk session queue node */
  int timerfd;

  /** Worker flags */
  session_wrk_flag_t flags;

  /** Worker state */
  session_wrk_state_t state;

  /** Context for session tx */
  session_tx_context_t ctx;

  /** Pool of session event list elements */
  session_evt_elt_t *event_elts;

  /** Pool of ctrl events data buffers */
  session_evt_ctrl_data_t *ctrl_evts_data;

  /** Head of control events list */
  clib_llist_index_t ctrl_head;

  /** Head of list of elements */
  clib_llist_index_t new_head;

  /** Head of list of pending events */
  clib_llist_index_t old_head;

  /** Vector of buffers to be sent */
  u32 *pending_tx_buffers;

  /** Vector of nexts for the pending tx buffers */
  u16 *pending_tx_nexts;

  /** Clib file for timerfd. Used only if adaptive mode is on */
  uword timerfd_file;

  /** List of pending connects for first worker */
  clib_llist_index_t pending_connects;

  /** Flag that is set if main thread signaled to handle connects */
  u32 n_pending_connects;

  /** Main thread loops in poll mode without a connect */
  u32 no_connect_loops;

  /** List head for first worker evts pending handling on main */
  clib_llist_index_t evts_pending_main;

  int config_index;
  u8 dma_enabled;
  session_dma_transfer *dma_trans;
  u16 trans_head;
  u16 trans_tail;
  u16 trans_size;
  u16 batch_num;
  vlib_dma_batch_t *batch;

#if SESSION_DEBUG
  /** last event poll time by thread */
  clib_time_type_t last_event_poll;
#endif
} session_worker_t;

typedef int (session_fifo_rx_fn) (session_worker_t * wrk,
				  vlib_node_runtime_t * node,
				  session_evt_elt_t * e, int *n_tx_packets);

extern session_fifo_rx_fn session_tx_fifo_peek_and_snd;
extern session_fifo_rx_fn session_tx_fifo_dequeue_and_snd;
extern session_fifo_rx_fn session_tx_fifo_dequeue_internal;

u8 session_node_lookup_fifo_event (svm_fifo_t * f, session_event_t * e);

typedef void (*session_update_time_fn) (f64 time_now, u8 thread_index);

typedef struct session_main_
{
  /** Worker contexts */
  session_worker_t *wrk;

  /** Vector of transport update time functions */
  session_update_time_fn *update_time_fns;

  /** Event queues memfd segment */
  fifo_segment_t wrk_mqs_segment;

  /** Unique segment name counter */
  u32 unique_segment_name_counter;

  /** Per transport rx function that can either dequeue or peek */
  session_fifo_rx_fn **session_tx_fns;

  /** Per session type output nodes. Could optimize to group nodes by
   * fib but lookup would then require session type parsing in session node.
   * Trade memory for speed, for now */
  u32 *session_type_to_next;

  /** Thread for cl and ho that rely on cl allocs */
  u32 transport_cl_thread;

  transport_proto_t last_transport_proto_type;

  /** Number of workers at pool realloc barrier */
  volatile u32 pool_realloc_at_barrier;

  /** Number of workers doing reallocs */
  volatile u32 pool_realloc_doing_work;

  /** Lock to synchronize parallel forced reallocs */
  clib_spinlock_t pool_realloc_lock;

  /*
   * Config parameters
   */

  /** Session manager is enabled */
  u8 is_enabled;

  /** Session manager initialized (not necessarily enabled) */
  u8 is_initialized;

  /** Enable session manager at startup */
  u8 session_enable_asap;

  /** Poll session node in main thread */
  u8 poll_main;

  /** Allocate private rx mqs for external apps */
  u8 use_private_rx_mqs;

  /** Do not enable session queue node adaptive mode */
  u8 no_adaptive;

  /** vpp fifo event queue configured length */
  u32 configured_wrk_mq_length;

  /** Session ssvm segment configs*/
  uword wrk_mqs_segment_size;

  /** Session enable dma*/
  u8 dma_enabled;

  /** Session table size parameters */
  u32 configured_v4_session_table_buckets;
  u32 configured_v4_session_table_memory;
  u32 configured_v4_halfopen_table_buckets;
  u32 configured_v4_halfopen_table_memory;
  u32 configured_v6_session_table_buckets;
  u32 configured_v6_session_table_memory;
  u32 configured_v6_halfopen_table_buckets;
  u32 configured_v6_halfopen_table_memory;

  /** Transport table (preallocation) size parameters */
  u32 local_endpoints_table_memory;
  u32 local_endpoints_table_buckets;

  /** Preallocate session config parameter */
  u32 preallocated_sessions;

  u16 msg_id_base;
} session_main_t;

extern session_main_t session_main;
extern vlib_node_registration_t session_queue_node;
extern vlib_node_registration_t session_queue_process_node;
extern vlib_node_registration_t session_queue_pre_input_node;

typedef enum session_q_process_evt_
{
  SESSION_Q_PROCESS_RUN_ON_MAIN = 1,
  SESSION_Q_PROCESS_STOP
} session_q_process_evt_t;

#define TRANSPORT_PROTO_INVALID (session_main.last_transport_proto_type + 1)
#define TRANSPORT_N_PROTOS (session_main.last_transport_proto_type + 1)

static inline void
session_evt_add_old (session_worker_t * wrk, session_evt_elt_t * elt)
{
  clib_llist_add_tail (wrk->event_elts, evt_list, elt,
		       clib_llist_elt (wrk->event_elts, wrk->old_head));
}

static inline void
session_evt_add_head_old (session_worker_t * wrk, session_evt_elt_t * elt)
{
  clib_llist_add (wrk->event_elts, evt_list, elt,
		  clib_llist_elt (wrk->event_elts, wrk->old_head));
}


static inline u32
session_evt_ctrl_data_alloc (session_worker_t * wrk)
{
  session_evt_ctrl_data_t *data;
  pool_get (wrk->ctrl_evts_data, data);
  return (data - wrk->ctrl_evts_data);
}

static inline session_evt_elt_t *
session_evt_alloc_ctrl (session_worker_t * wrk)
{
  session_evt_elt_t *elt;
  clib_llist_get (wrk->event_elts, elt);
  clib_llist_add_tail (wrk->event_elts, evt_list, elt,
		       clib_llist_elt (wrk->event_elts, wrk->ctrl_head));
  return elt;
}

static inline void *
session_evt_ctrl_data (session_worker_t * wrk, session_evt_elt_t * elt)
{
  return (void *) (pool_elt_at_index (wrk->ctrl_evts_data,
				      elt->evt.ctrl_data_index));
}

static inline void
session_evt_ctrl_data_free (session_worker_t * wrk, session_evt_elt_t * elt)
{
  ASSERT (elt->evt.event_type > SESSION_IO_EVT_BUILTIN_TX);
  pool_put_index (wrk->ctrl_evts_data, elt->evt.ctrl_data_index);
}

static inline session_evt_elt_t *
session_evt_alloc_new (session_worker_t * wrk)
{
  session_evt_elt_t *elt;
  clib_llist_get (wrk->event_elts, elt);
  clib_llist_add_tail (wrk->event_elts, evt_list, elt,
		       clib_llist_elt (wrk->event_elts, wrk->new_head));
  return elt;
}

static inline session_evt_elt_t *
session_evt_alloc_old (session_worker_t * wrk)
{
  session_evt_elt_t *elt;
  clib_llist_get (wrk->event_elts, elt);
  clib_llist_add_tail (wrk->event_elts, evt_list, elt,
		       clib_llist_elt (wrk->event_elts, wrk->old_head));
  return elt;
}

int session_wrk_handle_mq (session_worker_t *wrk, svm_msg_q_t *mq);

session_t *session_alloc (u32 thread_index);
void session_free (session_t * s);
void session_free_w_fifos (session_t * s);
void session_cleanup_half_open (session_handle_t ho_handle);
u8 session_is_valid (u32 si, u8 thread_index);

always_inline session_t *
session_get (u32 si, u32 thread_index)
{
  ASSERT (session_is_valid (si, thread_index));
  return pool_elt_at_index (session_main.wrk[thread_index].sessions, si);
}

always_inline session_t *
session_get_if_valid (u64 si, u32 thread_index)
{
  if (thread_index >= vec_len (session_main.wrk))
    return 0;

  if (pool_is_free_index (session_main.wrk[thread_index].sessions, si))
    return 0;

  ASSERT (session_is_valid (si, thread_index));
  return pool_elt_at_index (session_main.wrk[thread_index].sessions, si);
}

always_inline session_t *
session_get_from_handle (session_handle_t handle)
{
  session_main_t *smm = &session_main;
  u32 session_index, thread_index;
  session_parse_handle (handle, &session_index, &thread_index);
  return pool_elt_at_index (smm->wrk[thread_index].sessions, session_index);
}

always_inline session_t *
session_get_from_handle_if_valid (session_handle_t handle)
{
  u32 session_index, thread_index;
  session_parse_handle (handle, &session_index, &thread_index);
  return session_get_if_valid (session_index, thread_index);
}

u64 session_segment_handle (session_t * s);

/**
 * Get session from handle and avoid pool validation if no same thread
 *
 * Peekers are fine because pool grows with barrier (see @ref session_alloc)
 */
always_inline session_t *
session_get_from_handle_safe (u64 handle)
{
  u32 thread_index = session_thread_from_handle (handle);
  session_worker_t *wrk = &session_main.wrk[thread_index];

  if (thread_index == vlib_get_thread_index ())
    {
      return pool_elt_at_index (wrk->sessions,
				session_index_from_handle (handle));
    }
  else
    {
      /* Don't use pool_elt_at index to avoid pool bitmap reallocs */
      return wrk->sessions + session_index_from_handle (handle);
    }
}

always_inline session_t *
session_clone_safe (u32 session_index, u32 thread_index)
{
  u32 current_thread_index = vlib_get_thread_index (), new_index;
  session_t *old_s, *new_s;

  new_s = session_alloc (current_thread_index);
  new_index = new_s->session_index;
  /* Session pools are reallocated with barrier (see @ref session_alloc) */
  old_s = session_main.wrk[thread_index].sessions + session_index;
  clib_memcpy_fast (new_s, old_s, sizeof (*new_s));
  new_s->thread_index = current_thread_index;
  new_s->session_index = new_index;
  return new_s;
}

int session_open (session_endpoint_cfg_t *sep, session_handle_t *rsh);
int session_listen (session_t * s, session_endpoint_cfg_t * sep);
int session_stop_listen (session_t * s);
void session_half_close (session_t *s);
void session_close (session_t * s);
void session_reset (session_t * s);
void session_transport_half_close (session_t *s);
void session_transport_close (session_t * s);
void session_transport_reset (session_t * s);
void session_transport_cleanup (session_t * s);
int session_send_io_evt_to_thread (svm_fifo_t * f,
				   session_evt_type_t evt_type);
int session_enqueue_notify (session_t * s);
int session_dequeue_notify (session_t * s);
int session_send_io_evt_to_thread_custom (void *data, u32 thread_index,
					  session_evt_type_t evt_type);
void session_send_rpc_evt_to_thread (u32 thread_index, void *fp,
				     void *rpc_args);
void session_send_rpc_evt_to_thread_force (u32 thread_index, void *fp,
					   void *rpc_args);
void session_add_self_custom_tx_evt (transport_connection_t * tc,
				     u8 has_prio);
void sesssion_reschedule_tx (transport_connection_t * tc);
transport_connection_t *session_get_transport (session_t * s);
void session_get_endpoint (session_t * s, transport_endpoint_t * tep,
			   u8 is_lcl);
int session_transport_attribute (session_t *s, u8 is_get,
				 transport_endpt_attr_t *attr);

u8 *format_session (u8 * s, va_list * args);
uword unformat_session (unformat_input_t * input, va_list * args);
uword unformat_transport_connection (unformat_input_t * input,
				     va_list * args);

/*
 * Interface to transport protos
 */

int session_enqueue_stream_connection (transport_connection_t * tc,
				       vlib_buffer_t * b, u32 offset,
				       u8 queue_event, u8 is_in_order);
int session_enqueue_dgram_connection (session_t * s,
				      session_dgram_hdr_t * hdr,
				      vlib_buffer_t * b, u8 proto,
				      u8 queue_event);
int session_stream_connect_notify (transport_connection_t * tc,
				   session_error_t err);
int session_dgram_connect_notify (transport_connection_t * tc,
				  u32 old_thread_index,
				  session_t ** new_session);
int session_stream_accept_notify (transport_connection_t * tc);
void session_transport_closing_notify (transport_connection_t * tc);
void session_transport_delete_notify (transport_connection_t * tc);
void session_half_open_delete_notify (transport_connection_t *tc);
void session_half_open_migrate_notify (transport_connection_t *tc);
int session_half_open_migrated_notify (transport_connection_t *tc);
void session_transport_closed_notify (transport_connection_t * tc);
void session_transport_reset_notify (transport_connection_t * tc);
int session_stream_accept (transport_connection_t * tc, u32 listener_index,
			   u32 thread_index, u8 notify);
int session_dgram_accept (transport_connection_t * tc, u32 listener_index,
			  u32 thread_index);
/**
 * Initialize session layer for given transport proto and ip version
 *
 * Allocates per session type (transport proto + ip version) data structures
 * and adds arc from session queue node to session type output node.
 *
 * @param transport_proto 	transport proto to be registered
 * @param vft			virtual function table for transport
 * @param is_ip4		flag that indicates if transports uses ipv4
 * 				as underlying network layer
 * @param output_node		output node for transport
 */
void session_register_transport (transport_proto_t transport_proto,
				 const transport_proto_vft_t * vft, u8 is_ip4,
				 u32 output_node);
transport_proto_t session_add_transport_proto (void);
void session_register_update_time_fn (session_update_time_fn fn, u8 is_add);
int session_tx_fifo_peek_bytes (transport_connection_t * tc, u8 * buffer,
				u32 offset, u32 max_bytes);
u32 session_tx_fifo_dequeue_drop (transport_connection_t * tc, u32 max_bytes);

always_inline void
session_set_state (session_t *s, session_state_t session_state)
{
  s->session_state = session_state;
  SESSION_EVT (SESSION_EVT_STATE_CHANGE, s);
}

always_inline u32
transport_max_rx_enqueue (transport_connection_t * tc)
{
  session_t *s = session_get (tc->s_index, tc->thread_index);
  return svm_fifo_max_enqueue_prod (s->rx_fifo);
}

always_inline u32
transport_max_tx_dequeue (transport_connection_t * tc)
{
  session_t *s = session_get (tc->s_index, tc->thread_index);
  return svm_fifo_max_dequeue_cons (s->tx_fifo);
}

always_inline u32
transport_max_rx_dequeue (transport_connection_t * tc)
{
  session_t *s = session_get (tc->s_index, tc->thread_index);
  return svm_fifo_max_dequeue (s->rx_fifo);
}

always_inline u32
transport_rx_fifo_size (transport_connection_t * tc)
{
  session_t *s = session_get (tc->s_index, tc->thread_index);
  return svm_fifo_size (s->rx_fifo);
}

always_inline u32
transport_tx_fifo_size (transport_connection_t * tc)
{
  session_t *s = session_get (tc->s_index, tc->thread_index);
  return svm_fifo_size (s->tx_fifo);
}

always_inline u8
transport_rx_fifo_has_ooo_data (transport_connection_t * tc)
{
  session_t *s = session_get (tc->c_index, tc->thread_index);
  return svm_fifo_has_ooo_data (s->rx_fifo);
}

always_inline void
transport_rx_fifo_req_deq_ntf (transport_connection_t *tc)
{
  session_t *s = session_get (tc->s_index, tc->thread_index);
  svm_fifo_add_want_deq_ntf (s->rx_fifo, SVM_FIFO_WANT_DEQ_NOTIF);
}

always_inline clib_time_type_t
transport_time_now (u32 thread_index)
{
  return session_main.wrk[thread_index].last_vlib_time;
}

always_inline clib_us_time_t
transport_us_time_now (u32 thread_index)
{
  return session_main.wrk[thread_index].last_vlib_us_time;
}

always_inline clib_time_type_t
transport_seconds_per_loop (u32 thread_index)
{
  return session_main.wrk[thread_index].vm->seconds_per_loop;
}

always_inline void
transport_add_tx_event (transport_connection_t * tc)
{
  session_t *s = session_get (tc->s_index, tc->thread_index);
  if (svm_fifo_has_event (s->tx_fifo))
    return;
  session_send_io_evt_to_thread (s->tx_fifo, SESSION_IO_EVT_TX);
}

always_inline u32
transport_cl_thread (void)
{
  return session_main.transport_cl_thread;
}

/*
 * Listen sessions
 */

always_inline u64
listen_session_get_handle (session_t * s)
{
  ASSERT (s->session_state == SESSION_STATE_LISTENING ||
	  session_get_transport_proto (s) == TRANSPORT_PROTO_QUIC);
  return session_handle (s);
}

always_inline session_t *
listen_session_get_from_handle (session_handle_t handle)
{
  return session_get_from_handle (handle);
}

always_inline void
listen_session_parse_handle (session_handle_t handle, u32 * index,
			     u32 * thread_index)
{
  session_parse_handle (handle, index, thread_index);
}

always_inline session_t *
listen_session_alloc (u8 thread_index, session_type_t type)
{
  session_t *s;
  s = session_alloc (thread_index);
  s->session_type = type;
  s->session_state = SESSION_STATE_LISTENING;
  return s;
}

always_inline session_t *
listen_session_get (u32 ls_index)
{
  return session_get (ls_index, 0);
}

always_inline void
listen_session_free (session_t * s)
{
  ASSERT (!s->rx_fifo);
  session_free (s);
}

always_inline session_t *
ho_session_alloc (void)
{
  session_t *s;
  ASSERT (vlib_get_thread_index () == 0);
  s = session_alloc (0);
  s->session_state = SESSION_STATE_CONNECTING;
  s->flags |= SESSION_F_HALF_OPEN;
  /* Not ideal. Half-opens are only allocated from main with worker barrier
   * but can be cleaned up, i.e., session_half_open_free, from main without
   * a barrier. In debug images, the free_bitmap can grow while workers peek
   * the sessions pool, e.g., session_half_open_migrate_notify, and as a
   * result crash while validating the session. To avoid this, grow the bitmap
   * now. */
  if (CLIB_DEBUG)
    {
      session_t *sp = session_main.wrk[0].sessions;
      clib_bitmap_validate (pool_header (sp)->free_bitmap,
			    s->session_index + 1);
    }
  return s;
}

always_inline session_t *
ho_session_get (u32 ho_index)
{
  return session_get (ho_index, 0 /* half-open thread */);
}

always_inline void
ho_session_free (session_t *s)
{
  ASSERT (!s->rx_fifo && s->thread_index == 0);
  session_free (s);
}

transport_connection_t *listen_session_get_transport (session_t * s);

/*
 * Session layer functions
 */

always_inline session_main_t *
vnet_get_session_main ()
{
  return &session_main;
}

always_inline session_worker_t *
session_main_get_worker (u32 thread_index)
{
  return &session_main.wrk[thread_index];
}

static inline session_worker_t *
session_main_get_worker_if_valid (u32 thread_index)
{
  if (thread_index > vec_len (session_main.wrk))
    return 0;
  return &session_main.wrk[thread_index];
}

always_inline svm_msg_q_t *
session_main_get_vpp_event_queue (u32 thread_index)
{
  return session_main.wrk[thread_index].vpp_event_queue;
}

always_inline u8
session_main_is_enabled ()
{
  return session_main.is_enabled == 1;
}

#define session_cli_return_if_not_enabled()				\
do {									\
    if (!session_main.is_enabled)					\
      return clib_error_return (0, "session layer is not enabled");	\
} while (0)

int session_main_flush_enqueue_events (u8 proto, u32 thread_index);
int session_main_flush_all_enqueue_events (u8 transport_proto);
void session_queue_run_on_main_thread (vlib_main_t * vm);

/**
 * Add session node pending buffer with custom node
 *
 * @param thread_index 	worker thread expected to send the buffer
 * @param bi		buffer index
 * @param next_node	next node edge index for buffer. Edge to next node
 * 			must exist
 */
always_inline void
session_add_pending_tx_buffer (u32 thread_index, u32 bi, u32 next_node)
{
  session_worker_t *wrk = session_main_get_worker (thread_index);
  vec_add1 (wrk->pending_tx_buffers, bi);
  vec_add1 (wrk->pending_tx_nexts, next_node);
  if (PREDICT_FALSE (wrk->state == SESSION_WRK_INTERRUPT))
    vlib_node_set_interrupt_pending (wrk->vm, session_queue_node.index);
}

always_inline void
session_wrk_update_time (session_worker_t *wrk, f64 now)
{
  wrk->last_vlib_time = now;
  wrk->last_vlib_us_time = wrk->last_vlib_time * CLIB_US_TIME_FREQ;
}

void session_wrk_enable_adaptive_mode (session_worker_t *wrk);
fifo_segment_t *session_main_get_wrk_mqs_segment (void);
void session_node_enable_disable (u8 is_en);
clib_error_t *vnet_session_enable_disable (vlib_main_t * vm, u8 is_en);
void session_wrk_handle_evts_main_rpc (void *);

session_t *session_alloc_for_connection (transport_connection_t * tc);
session_t *session_alloc_for_half_open (transport_connection_t *tc);

typedef void (pool_safe_realloc_rpc_fn) (void *rpc_args);

typedef struct
{
  u8 ph[STRUCT_OFFSET_OF (pool_header_t, max_elts) + 4];
  u32 flag;
} pool_safe_realloc_header_t;

STATIC_ASSERT_SIZEOF (pool_safe_realloc_header_t, sizeof (pool_header_t));

#define POOL_REALLOC_SAFE_ELT_THRESH 32

#define pool_realloc_flag(PH)                                                 \
  ((pool_safe_realloc_header_t *) pool_header (PH))->flag

typedef struct pool_realloc_rpc_args_
{
  void **pool;
  uword elt_size;
  uword align;
} pool_realloc_rpc_args_t;

always_inline void
pool_program_safe_realloc_rpc (void *args)
{
  vlib_main_t *vm = vlib_get_main ();
  u32 free_elts, max_elts, n_alloc;
  pool_realloc_rpc_args_t *pra;

  ASSERT (vlib_get_thread_index () == 0);
  pra = (pool_realloc_rpc_args_t *) args;

  vlib_worker_thread_barrier_sync (vm);

  free_elts = _pool_free_elts (*pra->pool, pra->elt_size);
  if (free_elts < POOL_REALLOC_SAFE_ELT_THRESH)
    {
      max_elts = _vec_max_len (*pra->pool, pra->elt_size);
      n_alloc = clib_max (2 * max_elts, POOL_REALLOC_SAFE_ELT_THRESH);
      _pool_alloc (pra->pool, free_elts + n_alloc, pra->align, 0,
		   pra->elt_size);
    }
  pool_realloc_flag (*pra->pool) = 0;
  clib_mem_free (args);

  vlib_worker_thread_barrier_release (vm);
}

always_inline void
pool_program_safe_realloc (void **p, u32 elt_size, u32 align)
{
  pool_realloc_rpc_args_t *pra;

  /* Reuse pad as a realloc flag */
  if (pool_realloc_flag (*p))
    return;

  pra = clib_mem_alloc (sizeof (*pra));
  pra->pool = p;
  pra->elt_size = elt_size;
  pra->align = align;
  pool_realloc_flag (*p) = 1;

  session_send_rpc_evt_to_thread (0 /* thread index */,
				  pool_program_safe_realloc_rpc, pra);
}

#define pool_needs_realloc(P)                                                 \
  ((!P) ||                                                                    \
   (vec_len (pool_header (P)->free_indices) < POOL_REALLOC_SAFE_ELT_THRESH && \
    pool_free_elts (P) < POOL_REALLOC_SAFE_ELT_THRESH))

#define pool_get_aligned_safe(P, E, align)                                    \
  do                                                                          \
    {                                                                         \
      if (PREDICT_FALSE (pool_needs_realloc (P)))                             \
	{                                                                     \
	  if (PREDICT_FALSE (!(P)))                                           \
	    {                                                                 \
	      pool_alloc_aligned (P, POOL_REALLOC_SAFE_ELT_THRESH, align);    \
	    }                                                                 \
	  else if (PREDICT_FALSE (!pool_free_elts (P)))                       \
	    {                                                                 \
	      vlib_workers_sync ();                                           \
	      pool_alloc_aligned (P, pool_max_len (P), align);                \
	      vlib_workers_continue ();                                       \
	      ALWAYS_ASSERT (pool_free_elts (P) > 0);                         \
	    }                                                                 \
	  else                                                                \
	    {                                                                 \
	      pool_program_safe_realloc ((void **) &(P), sizeof ((P)[0]),     \
					 _vec_align (P, align));              \
	    }                                                                 \
	}                                                                     \
      pool_get_aligned (P, E, align);                                         \
    }                                                                         \
  while (0)

#endif /* __included_session_h__ */

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