src/vnet/session/segment_manager.c

   1 /*
   2  * Copyright (c) 2017-2019 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15
  16 #include <vnet/session/segment_manager.h>
  17 #include <vnet/session/session.h>
  18 #include <vnet/session/application.h>
  19
  20 typedef struct segment_manager_main_
  21 {
  22   segment_manager_t *segment_managers;  /**< Pool of segment managers */
  23   u32 seg_name_counter;                 /**< Counter for segment names */
  24
  25   /*
  26    * Configuration
  27    */
  28   u32 default_fifo_size;        /**< default rx/tx fifo size */
  29   u32 default_segment_size;     /**< default fifo segment size */
  30   u32 default_app_mq_size;      /**< default app msg q size */
  31   u32 default_max_fifo_size;    /**< default max fifo size */
  32   u8 default_high_watermark;    /**< default high watermark % */
  33   u8 default_low_watermark;     /**< default low watermark % */
  34 } segment_manager_main_t;
  35
  36 static segment_manager_main_t sm_main;
  37
  38 #define segment_manager_foreach_segment_w_lock(VAR, SM, BODY)           \
  39 do {                                                                    \
  40     clib_rwlock_reader_lock (&(SM)->segments_rwlock);                   \
  41     pool_foreach((VAR), ((SM)->segments)) (BODY);                       \
  42     clib_rwlock_reader_unlock (&(SM)->segments_rwlock);                 \
  43 } while (0)
  44
  45 static segment_manager_props_t *
  46 segment_manager_properties_get (segment_manager_t * sm)
  47 {
  48   app_worker_t *app_wrk = app_worker_get (sm->app_wrk_index);
  49   return application_get_segment_manager_properties (app_wrk->app_index);
  50 }
  51
  52 segment_manager_props_t *
  53 segment_manager_props_init (segment_manager_props_t * props)
  54 {
  55   props->add_segment_size = sm_main.default_segment_size;
  56   props->rx_fifo_size = sm_main.default_fifo_size;
  57   props->tx_fifo_size = sm_main.default_fifo_size;
  58   props->evt_q_size = sm_main.default_app_mq_size;
  59   props->max_fifo_size = sm_main.default_max_fifo_size;
  60   props->high_watermark = sm_main.default_high_watermark;
  61   props->low_watermark = sm_main.default_low_watermark;
  62   props->n_slices = vlib_num_workers () + 1;
  63   return props;
  64 }
  65
  66 u8
  67 segment_manager_app_detached (segment_manager_t * sm)
  68 {
  69   return (sm->flags & SEG_MANAGER_F_DETACHED);
  70 }
  71
  72 void
  73 segment_manager_app_detach (segment_manager_t * sm)
  74 {
  75   sm->flags |= SEG_MANAGER_F_DETACHED;
  76 }
  77
  78 always_inline u32
  79 segment_manager_segment_index (segment_manager_t * sm, fifo_segment_t * seg)
  80 {
  81   return (seg - sm->segments);
  82 }
  83
  84 /**
  85  * Adds segment to segment manager's pool
  86  *
  87  * If needed a writer's lock is acquired before allocating a new segment
  88  * to avoid affecting any of the segments pool readers.
  89  */
  90 int
  91 segment_manager_add_segment (segment_manager_t *sm, uword segment_size,
  92                              u8 notify_app)
  93 {
  94   segment_manager_main_t *smm = &sm_main;
  95   segment_manager_props_t *props;
  96   fifo_segment_t *fs;
  97   u32 fs_index = ~0;
  98   u8 *seg_name;
  99   int rv;
 100
 101   props = segment_manager_properties_get (sm);
 102
 103   /* Not configured for addition of new segments and not first */
 104   if (!props->add_segment && !segment_size)
 105     {
 106       clib_warning ("cannot allocate new segment");
 107       return VNET_API_ERROR_INVALID_VALUE;
 108     }
 109
 110   /*
 111    * Allocate fifo segment and grab lock if needed
 112    */
 113   if (vlib_num_workers ())
 114     clib_rwlock_writer_lock (&sm->segments_rwlock);
 115
 116   pool_get_zero (sm->segments, fs);
 117
 118   /*
 119    * Allocate ssvm segment
 120    */
 121   segment_size = segment_size ? segment_size : props->add_segment_size;
 122   segment_size = round_pow2 (segment_size, clib_mem_get_page_size ());
 123
 124   if (props->segment_type != SSVM_SEGMENT_PRIVATE)
 125     {
 126       seg_name = format (0, "%d-%d%c", getpid (), smm->seg_name_counter++, 0);
 127     }
 128   else
 129     {
 130       app_worker_t *app_wrk = app_worker_get (sm->app_wrk_index);
 131       application_t *app = application_get (app_wrk->app_index);
 132       seg_name = format (0, "%v segment%c", app->name, 0);
 133     }
 134
 135   fs->ssvm.ssvm_size = segment_size;
 136   fs->ssvm.name = seg_name;
 137   fs->ssvm.requested_va = 0;
 138
 139   if ((rv = ssvm_server_init (&fs->ssvm, props->segment_type)))
 140     {
 141       clib_warning ("svm_master_init ('%v', %u) failed", seg_name,
 142                     segment_size);
 143       pool_put (sm->segments, fs);
 144       goto done;
 145     }
 146
 147   /*
 148    * Initialize fifo segment
 149    */
 150   fs->n_slices = props->n_slices;
 151   fifo_segment_init (fs);
 152
 153   /*
 154    * Save segment index before dropping lock, if any held
 155    */
 156   fs_index = fs - sm->segments;
 157
 158   /*
 159    * Set watermarks in segment
 160    */
 161   fs->h->high_watermark = sm->high_watermark;
 162   fs->h->low_watermark = sm->low_watermark;
 163   fs->h->pct_first_alloc = props->pct_first_alloc;
 164   fs->h->flags &= ~FIFO_SEGMENT_F_MEM_LIMIT;
 165
 166   if (notify_app)
 167     {
 168       app_worker_t *app_wrk;
 169       u64 fs_handle;
 170       fs_handle = segment_manager_segment_handle (sm, fs);
 171       app_wrk = app_worker_get (sm->app_wrk_index);
 172       rv = app_worker_add_segment_notify (app_wrk, fs_handle);
 173       if (rv)
 174         return rv;
 175     }
 176 done:
 177
 178   if (vlib_num_workers ())
 179     clib_rwlock_writer_unlock (&sm->segments_rwlock);
 180
 181   return fs_index;
 182 }
 183
 184 /**
 185  * Remove segment without lock
 186  */
 187 void
 188 segment_manager_del_segment (segment_manager_t * sm, fifo_segment_t * fs)
 189 {
 190   if (ssvm_type (&fs->ssvm) != SSVM_SEGMENT_PRIVATE)
 191     {
 192       if (!segment_manager_app_detached (sm))
 193         {
 194           app_worker_t *app_wrk;
 195           u64 segment_handle;
 196           app_wrk = app_worker_get (sm->app_wrk_index);
 197           segment_handle = segment_manager_segment_handle (sm, fs);
 198           app_worker_del_segment_notify (app_wrk, segment_handle);
 199         }
 200     }
 201
 202   fifo_segment_cleanup (fs);
 203   ssvm_delete (&fs->ssvm);
 204
 205   if (CLIB_DEBUG)
 206     clib_memset (fs, 0xfb, sizeof (*fs));
 207   pool_put (sm->segments, fs);
 208 }
 209
 210 static fifo_segment_t *
 211 segment_manager_get_segment_if_valid (segment_manager_t * sm,
 212                                       u32 segment_index)
 213 {
 214   if (pool_is_free_index (sm->segments, segment_index))
 215     return 0;
 216   return pool_elt_at_index (sm->segments, segment_index);
 217 }
 218
 219 /**
 220  * Removes segment after acquiring writer lock
 221  */
 222 static inline void
 223 sm_lock_and_del_segment_inline (segment_manager_t * sm, u32 fs_index)
 224 {
 225   fifo_segment_t *fs;
 226   u8 is_prealloc;
 227
 228   clib_rwlock_writer_lock (&sm->segments_rwlock);
 229
 230   fs = segment_manager_get_segment_if_valid (sm, fs_index);
 231   if (!fs)
 232     goto done;
 233
 234   is_prealloc = fifo_segment_flags (fs) & FIFO_SEGMENT_F_IS_PREALLOCATED;
 235   if (is_prealloc && !segment_manager_app_detached (sm))
 236     goto done;
 237
 238   segment_manager_del_segment (sm, fs);
 239
 240 done:
 241   clib_rwlock_writer_unlock (&sm->segments_rwlock);
 242 }
 243
 244 void
 245 segment_manager_lock_and_del_segment (segment_manager_t * sm, u32 fs_index)
 246 {
 247   sm_lock_and_del_segment_inline (sm, fs_index);
 248 }
 249
 250 /**
 251  * Reads a segment from the segment manager's pool without lock
 252  */
 253 fifo_segment_t *
 254 segment_manager_get_segment (segment_manager_t * sm, u32 segment_index)
 255 {
 256   return pool_elt_at_index (sm->segments, segment_index);
 257 }
 258
 259 u64
 260 segment_manager_segment_handle (segment_manager_t * sm,
 261                                 fifo_segment_t * segment)
 262 {
 263   u32 segment_index = segment_manager_segment_index (sm, segment);
 264   return (((u64) segment_manager_index (sm) << 32) | segment_index);
 265 }
 266
 267 u64
 268 segment_manager_make_segment_handle (u32 segment_manager_index,
 269                                      u32 segment_index)
 270 {
 271   return (((u64) segment_manager_index << 32) | segment_index);
 272 }
 273
 274 fifo_segment_t *
 275 segment_manager_get_segment_w_handle (u64 segment_handle)
 276 {
 277   u32 sm_index, segment_index;
 278   segment_manager_t *sm;
 279
 280   segment_manager_parse_segment_handle (segment_handle, &sm_index,
 281                                         &segment_index);
 282   sm = segment_manager_get (sm_index);
 283   if (!sm || pool_is_free_index (sm->segments, segment_index))
 284     return 0;
 285   return pool_elt_at_index (sm->segments, segment_index);
 286 }
 287
 288 /**
 289  * Reads a segment from the segment manager's pool and acquires reader lock
 290  *
 291  * Caller must drop the reader's lock by calling
 292  * @ref segment_manager_segment_reader_unlock once it finishes working with
 293  * the segment.
 294  */
 295 fifo_segment_t *
 296 segment_manager_get_segment_w_lock (segment_manager_t * sm, u32 segment_index)
 297 {
 298   clib_rwlock_reader_lock (&sm->segments_rwlock);
 299   return pool_elt_at_index (sm->segments, segment_index);
 300 }
 301
 302 void
 303 segment_manager_segment_reader_lock (segment_manager_t * sm)
 304 {
 305   clib_rwlock_reader_lock (&sm->segments_rwlock);
 306 }
 307
 308 void
 309 segment_manager_segment_reader_unlock (segment_manager_t * sm)
 310 {
 311   clib_rwlock_reader_unlock (&sm->segments_rwlock);
 312 }
 313
 314 void
 315 segment_manager_segment_writer_unlock (segment_manager_t * sm)
 316 {
 317   clib_rwlock_writer_unlock (&sm->segments_rwlock);
 318 }
 319
 320 segment_manager_t *
 321 segment_manager_alloc (void)
 322 {
 323   segment_manager_main_t *smm = &sm_main;
 324   segment_manager_t *sm;
 325
 326   pool_get_zero (smm->segment_managers, sm);
 327   clib_rwlock_init (&sm->segments_rwlock);
 328   return sm;
 329 }
 330
 331 int
 332 segment_manager_init (segment_manager_t * sm)
 333 {
 334   segment_manager_props_t *props;
 335
 336   props = segment_manager_properties_get (sm);
 337
 338   sm->max_fifo_size = props->max_fifo_size ?
 339     props->max_fifo_size : sm_main.default_max_fifo_size;
 340   sm->max_fifo_size = clib_max (sm->max_fifo_size, 4096);
 341
 342   segment_manager_set_watermarks (sm,
 343                                   props->high_watermark,
 344                                   props->low_watermark);
 345   return 0;
 346 }
 347
 348 /**
 349  * Initializes segment manager based on options provided.
 350  * Returns error if ssvm segment(s) allocation fails.
 351  */
 352 int
 353 segment_manager_init_first (segment_manager_t * sm)
 354 {
 355   segment_manager_props_t *props;
 356   uword first_seg_size;
 357   fifo_segment_t *fs;
 358   int fs_index, i;
 359
 360   segment_manager_init (sm);
 361   props = segment_manager_properties_get (sm);
 362   first_seg_size = clib_max (props->segment_size,
 363                              sm_main.default_segment_size);
 364
 365   if (props->prealloc_fifos)
 366     {
 367       u64 approx_total_size, max_seg_size = ((u64) 1 << 32) - (128 << 10);
 368       u32 rx_rounded_data_size, tx_rounded_data_size;
 369       u32 prealloc_fifo_pairs = props->prealloc_fifos;
 370       u32 rx_fifo_size, tx_fifo_size, pair_size;
 371       u32 approx_segment_count;
 372
 373       /* Figure out how many segments should be preallocated */
 374       rx_rounded_data_size = (1 << (max_log2 (props->rx_fifo_size)));
 375       tx_rounded_data_size = (1 << (max_log2 (props->tx_fifo_size)));
 376
 377       rx_fifo_size = sizeof (svm_fifo_t) + rx_rounded_data_size;
 378       tx_fifo_size = sizeof (svm_fifo_t) + tx_rounded_data_size;
 379       pair_size = rx_fifo_size + tx_fifo_size;
 380
 381       approx_total_size = (u64) prealloc_fifo_pairs *pair_size;
 382       if (first_seg_size > approx_total_size)
 383         max_seg_size = first_seg_size;
 384       approx_segment_count = (approx_total_size + (max_seg_size - 1))
 385         / max_seg_size;
 386
 387       /* Allocate the segments */
 388       for (i = 0; i < approx_segment_count + 1; i++)
 389         {
 390           fs_index = segment_manager_add_segment (sm, max_seg_size, 0);
 391           if (fs_index < 0)
 392             {
 393               clib_warning ("Failed to preallocate segment %d", i);
 394               return fs_index;
 395             }
 396
 397           fs = segment_manager_get_segment (sm, fs_index);
 398           if (i == 0)
 399             sm->event_queue = segment_manager_alloc_queue (fs, props);
 400
 401           fifo_segment_preallocate_fifo_pairs (fs,
 402                                                props->rx_fifo_size,
 403                                                props->tx_fifo_size,
 404                                                &prealloc_fifo_pairs);
 405           fifo_segment_flags (fs) = FIFO_SEGMENT_F_IS_PREALLOCATED;
 406           if (prealloc_fifo_pairs == 0)
 407             break;
 408         }
 409       return 0;
 410     }
 411
 412   fs_index = segment_manager_add_segment (sm, first_seg_size, 0);
 413   if (fs_index < 0)
 414     {
 415       clib_warning ("Failed to allocate segment");
 416       return fs_index;
 417     }
 418
 419   fs = segment_manager_get_segment (sm, fs_index);
 420   sm->event_queue = segment_manager_alloc_queue (fs, props);
 421
 422   if (props->prealloc_fifo_hdrs)
 423     {
 424       u32 hdrs_per_slice;
 425
 426       /* Do not preallocate on slice associated to main thread */
 427       i = (vlib_num_workers ()? 1 : 0);
 428       hdrs_per_slice = props->prealloc_fifo_hdrs / (fs->n_slices - i);
 429
 430       for (; i < fs->n_slices; i++)
 431         {
 432           if (fifo_segment_prealloc_fifo_hdrs (fs, i, hdrs_per_slice))
 433             return VNET_API_ERROR_SVM_SEGMENT_CREATE_FAIL;
 434         }
 435     }
 436
 437   return 0;
 438 }
 439
 440 void
 441 segment_manager_cleanup_detached_listener (segment_manager_t * sm)
 442 {
 443   app_worker_t *app_wrk;
 444
 445   app_wrk = app_worker_get_if_valid (sm->app_wrk_index);
 446   if (!app_wrk)
 447     return;
 448
 449   app_worker_del_detached_sm (app_wrk, segment_manager_index (sm));
 450 }
 451
 452 /**
 453  * Cleanup segment manager.
 454  */
 455 void
 456 segment_manager_free (segment_manager_t * sm)
 457 {
 458   segment_manager_main_t *smm = &sm_main;
 459   fifo_segment_t *fifo_segment;
 460
 461   ASSERT (vlib_get_thread_index () == 0
 462           && !segment_manager_has_fifos (sm)
 463           && segment_manager_app_detached (sm));
 464
 465   if (sm->flags & SEG_MANAGER_F_DETACHED_LISTENER)
 466     segment_manager_cleanup_detached_listener (sm);
 467
 468   /* If we have empty preallocated segments that haven't been removed, remove
 469    * them now. Apart from that, the first segment in the first segment manager
 470    * is not removed when all fifos are removed. It can only be removed when
 471    * the manager is explicitly deleted/detached by the app. */
 472   clib_rwlock_writer_lock (&sm->segments_rwlock);
 473
 474   /* *INDENT-OFF* */
 475   pool_foreach (fifo_segment, sm->segments)  {
 476     segment_manager_del_segment (sm, fifo_segment);
 477   }
 478   /* *INDENT-ON* */
 479
 480   pool_free (sm->segments);
 481   clib_rwlock_writer_unlock (&sm->segments_rwlock);
 482
 483   clib_rwlock_free (&sm->segments_rwlock);
 484   if (CLIB_DEBUG)
 485     clib_memset (sm, 0xfe, sizeof (*sm));
 486   pool_put (smm->segment_managers, sm);
 487 }
 488
 489 static void
 490 sm_free_w_index_helper (void *arg)
 491 {
 492   u32 sm_index = *(u32 *) arg;
 493   segment_manager_t *sm;
 494
 495   ASSERT (vlib_get_thread_index () == 0);
 496
 497   if ((sm = segment_manager_get_if_valid (sm_index)))
 498     segment_manager_free (sm);
 499 }
 500
 501 static void
 502 segment_manager_free_safe (segment_manager_t * sm)
 503 {
 504   if (!vlib_thread_is_main_w_barrier ())
 505     {
 506       u32 sm_index = segment_manager_index (sm);
 507       vlib_rpc_call_main_thread (sm_free_w_index_helper, (u8 *) & sm_index,
 508                                  sizeof (sm_index));
 509     }
 510   else
 511     {
 512       segment_manager_free (sm);
 513     }
 514 }
 515
 516 void
 517 segment_manager_init_free (segment_manager_t * sm)
 518 {
 519   ASSERT (vlib_get_thread_index () == 0);
 520
 521   segment_manager_app_detach (sm);
 522   if (segment_manager_has_fifos (sm))
 523     segment_manager_del_sessions (sm);
 524   else
 525     {
 526       ASSERT (!sm->first_is_protected || segment_manager_app_detached (sm));
 527       segment_manager_free (sm);
 528     }
 529 }
 530
 531 segment_manager_t *
 532 segment_manager_get (u32 index)
 533 {
 534   return pool_elt_at_index (sm_main.segment_managers, index);
 535 }
 536
 537 segment_manager_t *
 538 segment_manager_get_if_valid (u32 index)
 539 {
 540   if (pool_is_free_index (sm_main.segment_managers, index))
 541     return 0;
 542   return pool_elt_at_index (sm_main.segment_managers, index);
 543 }
 544
 545 u32
 546 segment_manager_index (segment_manager_t * sm)
 547 {
 548   return sm - sm_main.segment_managers;
 549 }
 550
 551 u8
 552 segment_manager_has_fifos (segment_manager_t * sm)
 553 {
 554   fifo_segment_t *seg;
 555   u8 first = 1;
 556
 557   /* *INDENT-OFF* */
 558   segment_manager_foreach_segment_w_lock (seg, sm, ({
 559     if (CLIB_DEBUG && !first && !fifo_segment_has_fifos (seg)
 560         && !(fifo_segment_flags (seg) & FIFO_SEGMENT_F_IS_PREALLOCATED))
 561       {
 562         clib_warning ("segment %d has no fifos!",
 563                       segment_manager_segment_index (sm, seg));
 564         first = 0;
 565       }
 566     if (fifo_segment_has_fifos (seg))
 567       {
 568         segment_manager_segment_reader_unlock (sm);
 569         return 1;
 570       }
 571   }));
 572   /* *INDENT-ON* */
 573
 574   return 0;
 575 }
 576
 577 /**
 578  * Initiate disconnects for all sessions 'owned' by a segment manager
 579  */
 580 void
 581 segment_manager_del_sessions (segment_manager_t * sm)
 582 {
 583   session_handle_t *handles = 0, *handle;
 584   fifo_segment_t *fs;
 585   session_t *session;
 586   int slice_index;
 587   svm_fifo_t *f;
 588
 589   ASSERT (pool_elts (sm->segments) != 0);
 590
 591   /* Across all fifo segments used by the server */
 592   /* *INDENT-OFF* */
 593   segment_manager_foreach_segment_w_lock (fs, sm, ({
 594     for (slice_index = 0; slice_index < fs->n_slices; slice_index++)
 595       {
 596         f = fifo_segment_get_slice_fifo_list (fs, slice_index);
 597
 598         /*
 599          * Remove any residual sessions from the session lookup table
 600          * Don't bother deleting the individual fifos, we're going to
 601          * throw away the fifo segment in a minute.
 602          */
 603         while (f)
 604           {
 605             session = session_get_if_valid (f->shr->master_session_index,
 606                                             f->master_thread_index);
 607             if (session)
 608               vec_add1 (handles, session_handle (session));
 609             f = f->next;
 610           }
 611       }
 612
 613     /* Instead of removing the segment, test when cleaning up disconnected
 614      * sessions if the segment can be removed.
 615      */
 616   }));
 617   /* *INDENT-ON* */
 618
 619   vec_foreach (handle, handles)
 620   {
 621     session = session_get_from_handle (*handle);
 622     session_close (session);
 623     /* Avoid propagating notifications back to the app */
 624     session->app_wrk_index = APP_INVALID_INDEX;
 625   }
 626   vec_free (handles);
 627 }
 628
 629 int
 630 segment_manager_try_alloc_fifos (fifo_segment_t * fifo_segment,
 631                                  u32 thread_index,
 632                                  u32 rx_fifo_size, u32 tx_fifo_size,
 633                                  svm_fifo_t ** rx_fifo, svm_fifo_t ** tx_fifo)
 634 {
 635   rx_fifo_size = clib_max (rx_fifo_size, sm_main.default_fifo_size);
 636   *rx_fifo = fifo_segment_alloc_fifo_w_slice (fifo_segment, thread_index,
 637                                               rx_fifo_size,
 638                                               FIFO_SEGMENT_RX_FIFO);
 639
 640   tx_fifo_size = clib_max (tx_fifo_size, sm_main.default_fifo_size);
 641   *tx_fifo = fifo_segment_alloc_fifo_w_slice (fifo_segment, thread_index,
 642                                               tx_fifo_size,
 643                                               FIFO_SEGMENT_TX_FIFO);
 644
 645   if (*rx_fifo == 0)
 646     {
 647       /* This would be very odd, but handle it... */
 648       if (*tx_fifo != 0)
 649         {
 650           fifo_segment_free_fifo (fifo_segment, *tx_fifo);
 651           *tx_fifo = 0;
 652         }
 653       return -1;
 654     }
 655   if (*tx_fifo == 0)
 656     {
 657       if (*rx_fifo != 0)
 658         {
 659           fifo_segment_free_fifo (fifo_segment, *rx_fifo);
 660           *rx_fifo = 0;
 661         }
 662       return -1;
 663     }
 664
 665   return 0;
 666 }
 667
 668 int
 669 segment_manager_alloc_session_fifos (segment_manager_t * sm,
 670                                      u32 thread_index,
 671                                      svm_fifo_t ** rx_fifo,
 672                                      svm_fifo_t ** tx_fifo)
 673 {
 674   int alloc_fail = 1, rv = 0, new_fs_index;
 675   uword free_bytes, max_free_bytes = 0;
 676   segment_manager_props_t *props;
 677   fifo_segment_t *fs = 0, *cur;
 678   u32 sm_index, fs_index;
 679
 680   props = segment_manager_properties_get (sm);
 681
 682   /*
 683    * Find the first free segment to allocate the fifos in
 684    */
 685
 686   segment_manager_segment_reader_lock (sm);
 687
 688   /* *INDENT-OFF* */
 689   pool_foreach (cur, sm->segments)  {
 690     free_bytes = fifo_segment_available_bytes (cur);
 691     if (free_bytes > max_free_bytes)
 692       {
 693         max_free_bytes = free_bytes;
 694         fs = cur;
 695       }
 696   }
 697   /* *INDENT-ON* */
 698
 699   if (fs)
 700     {
 701       alloc_fail = segment_manager_try_alloc_fifos (fs, thread_index,
 702                                                     props->rx_fifo_size,
 703                                                     props->tx_fifo_size,
 704                                                     rx_fifo, tx_fifo);
 705       /* On success, keep lock until fifos are initialized */
 706       if (!alloc_fail)
 707         goto alloc_success;
 708     }
 709
 710   segment_manager_segment_reader_unlock (sm);
 711
 712   /*
 713    * Allocation failed, see if we can add a new segment
 714    */
 715   if (props->add_segment)
 716     {
 717       if ((new_fs_index = segment_manager_add_segment (sm, 0, 1)) < 0)
 718         {
 719           clib_warning ("Failed to add new segment");
 720           return SESSION_E_SEG_CREATE;
 721         }
 722       fs = segment_manager_get_segment_w_lock (sm, new_fs_index);
 723       alloc_fail = segment_manager_try_alloc_fifos (fs, thread_index,
 724                                                     props->rx_fifo_size,
 725                                                     props->tx_fifo_size,
 726                                                     rx_fifo, tx_fifo);
 727       if (alloc_fail)
 728         {
 729           clib_warning ("Added a segment, still can't allocate a fifo");
 730           segment_manager_segment_reader_unlock (sm);
 731           return SESSION_E_SEG_NO_SPACE2;
 732         }
 733     }
 734   else
 735     {
 736       SESSION_DBG ("Can't add new seg and no space to allocate fifos!");
 737       return SESSION_E_SEG_NO_SPACE;
 738     }
 739
 740 alloc_success:
 741   ASSERT (rx_fifo && tx_fifo);
 742
 743   sm_index = segment_manager_index (sm);
 744   fs_index = segment_manager_segment_index (sm, fs);
 745   (*tx_fifo)->segment_manager = sm_index;
 746   (*rx_fifo)->segment_manager = sm_index;
 747   (*tx_fifo)->segment_index = fs_index;
 748   (*rx_fifo)->segment_index = fs_index;
 749
 750   /* Drop the lock after app is notified */
 751   segment_manager_segment_reader_unlock (sm);
 752
 753   return rv;
 754 }
 755
 756 void
 757 segment_manager_dealloc_fifos (svm_fifo_t * rx_fifo, svm_fifo_t * tx_fifo)
 758 {
 759   segment_manager_t *sm;
 760   fifo_segment_t *fs;
 761   u32 segment_index;
 762
 763   if (!rx_fifo || !tx_fifo)
 764     return;
 765
 766   /* It's possible to have no segment manager if the session was removed
 767    * as result of a detach. */
 768   if (!(sm = segment_manager_get_if_valid (rx_fifo->segment_manager)))
 769     return;
 770
 771   segment_index = rx_fifo->segment_index;
 772   fs = segment_manager_get_segment_w_lock (sm, segment_index);
 773   fifo_segment_free_fifo (fs, rx_fifo);
 774   fifo_segment_free_fifo (fs, tx_fifo);
 775
 776   /*
 777    * Try to remove svm segment if it has no fifos. This can be done only if
 778    * the segment is not the first in the segment manager or if it is first
 779    * and it is not protected. Moreover, if the segment is first and the app
 780    * has detached from the segment manager, remove the segment manager.
 781    */
 782   if (!fifo_segment_has_fifos (fs))
 783     {
 784       segment_manager_segment_reader_unlock (sm);
 785
 786       /* Remove segment if it holds no fifos or first but not protected */
 787       if (segment_index != 0 || !sm->first_is_protected)
 788         sm_lock_and_del_segment_inline (sm, segment_index);
 789
 790       /* Remove segment manager if no sessions and detached from app */
 791       if (segment_manager_app_detached (sm)
 792           && !segment_manager_has_fifos (sm))
 793         segment_manager_free_safe (sm);
 794     }
 795   else
 796     segment_manager_segment_reader_unlock (sm);
 797 }
 798
 799 void
 800 segment_manager_detach_fifo (segment_manager_t *sm, svm_fifo_t **f)
 801 {
 802   fifo_segment_t *fs;
 803
 804   fs = segment_manager_get_segment_w_lock (sm, (*f)->segment_index);
 805   fifo_segment_detach_fifo (fs, f);
 806   segment_manager_segment_reader_unlock (sm);
 807 }
 808
 809 void
 810 segment_manager_attach_fifo (segment_manager_t *sm, svm_fifo_t **f,
 811                              session_t *s)
 812 {
 813   fifo_segment_t *fs;
 814
 815   fs = segment_manager_get_segment_w_lock (sm, (*f)->segment_index);
 816   fifo_segment_attach_fifo (fs, f, s->thread_index);
 817   segment_manager_segment_reader_unlock (sm);
 818
 819   (*f)->shr->master_session_index = s->session_index;
 820   (*f)->master_thread_index = s->thread_index;
 821 }
 822
 823 u32
 824 segment_manager_evt_q_expected_size (u32 q_len)
 825 {
 826   u32 fifo_evt_size, notif_q_size, q_hdrs;
 827   u32 msg_q_sz, fifo_evt_ring_sz, session_ntf_ring_sz;
 828
 829   fifo_evt_size = 1 << max_log2 (sizeof (session_event_t));
 830   notif_q_size = clib_max (16, q_len >> 4);
 831
 832   msg_q_sz = q_len * sizeof (svm_msg_q_msg_t);
 833   fifo_evt_ring_sz = q_len * fifo_evt_size;
 834   session_ntf_ring_sz = notif_q_size * 256;
 835   q_hdrs = sizeof (svm_queue_t) + sizeof (svm_msg_q_t);
 836
 837   return (msg_q_sz + fifo_evt_ring_sz + session_ntf_ring_sz + q_hdrs);
 838 }
 839
 840 /**
 841  * Allocates shm queue in the first segment
 842  *
 843  * Must be called with lock held
 844  */
 845 svm_msg_q_t *
 846 segment_manager_alloc_queue (fifo_segment_t * segment,
 847                              segment_manager_props_t * props)
 848 {
 849   u32 fifo_evt_size, session_evt_size = 256, notif_q_size;
 850   svm_msg_q_cfg_t _cfg, *cfg = &_cfg;
 851   svm_msg_q_t *q;
 852
 853   fifo_evt_size = sizeof (session_event_t);
 854   notif_q_size = clib_max (16, props->evt_q_size >> 4);
 855   /* *INDENT-OFF* */
 856   svm_msg_q_ring_cfg_t rc[SESSION_MQ_N_RINGS] = {
 857     {props->evt_q_size, fifo_evt_size, 0},
 858     {notif_q_size, session_evt_size, 0}
 859   };
 860   /* *INDENT-ON* */
 861   cfg->consumer_pid = 0;
 862   cfg->n_rings = 2;
 863   cfg->q_nitems = props->evt_q_size;
 864   cfg->ring_cfgs = rc;
 865
 866   q = fifo_segment_msg_q_alloc (segment, 0, cfg);
 867
 868   if (props->use_mq_eventfd)
 869     {
 870       if (svm_msg_q_alloc_eventfd (q))
 871         clib_warning ("failed to alloc eventfd");
 872     }
 873   return q;
 874 }
 875
 876 svm_msg_q_t *
 877 segment_manager_event_queue (segment_manager_t * sm)
 878 {
 879   return sm->event_queue;
 880 }
 881
 882 /**
 883  * Frees shm queue allocated in the first segment
 884  */
 885 void
 886 segment_manager_dealloc_queue (segment_manager_t * sm, svm_queue_t * q)
 887 {
 888   fifo_segment_t *segment;
 889   ssvm_shared_header_t *sh;
 890   void *oldheap;
 891
 892   ASSERT (!pool_is_free_index (sm->segments, 0));
 893
 894   segment = segment_manager_get_segment_w_lock (sm, 0);
 895   sh = segment->ssvm.sh;
 896
 897   oldheap = ssvm_push_heap (sh);
 898   svm_queue_free (q);
 899   ssvm_pop_heap (oldheap);
 900   segment_manager_segment_reader_unlock (sm);
 901 }
 902
 903 /*
 904  * Init segment vm address allocator
 905  */
 906 void
 907 segment_manager_main_init (void)
 908 {
 909   segment_manager_main_t *sm = &sm_main;
 910
 911   sm->default_fifo_size = 1 << 12;
 912   sm->default_segment_size = 1 << 20;
 913   sm->default_app_mq_size = 128;
 914   sm->default_max_fifo_size = 4 << 20;
 915   sm->default_high_watermark = 80;
 916   sm->default_low_watermark = 50;
 917 }
 918
 919 static clib_error_t *
 920 segment_manager_show_fn (vlib_main_t * vm, unformat_input_t * input,
 921                          vlib_cli_command_t * cmd)
 922 {
 923   segment_manager_main_t *smm = &sm_main;
 924   u8 show_segments = 0, verbose = 0;
 925   uword max_fifo_size;
 926   segment_manager_t *sm;
 927   fifo_segment_t *seg;
 928   app_worker_t *app_wrk;
 929   application_t *app;
 930   u8 custom_logic;
 931
 932   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
 933     {
 934       if (unformat (input, "segments"))
 935         show_segments = 1;
 936       else if (unformat (input, "verbose"))
 937         verbose = 1;
 938       else
 939         return clib_error_return (0, "unknown input `%U'",
 940                                   format_unformat_error, input);
 941     }
 942   vlib_cli_output (vm, "%d segment managers allocated",
 943                    pool_elts (smm->segment_managers));
 944   if (verbose && pool_elts (smm->segment_managers))
 945     {
 946       vlib_cli_output (vm, "%-6s%=10s%=10s%=13s%=11s%=11s%=12s",
 947                        "Index", "AppIndex", "Segments", "MaxFifoSize",
 948                        "HighWater", "LowWater", "FifoTuning");
 949
 950       /* *INDENT-OFF* */
 951       pool_foreach (sm, smm->segment_managers)  {
 952         app_wrk = app_worker_get_if_valid (sm->app_wrk_index);
 953         app = app_wrk ? application_get (app_wrk->app_index) : 0;
 954         custom_logic = (app && (app->cb_fns.fifo_tuning_callback)) ? 1 : 0;
 955         max_fifo_size = sm->max_fifo_size;
 956
 957         vlib_cli_output (vm, "%-6d%=10d%=10d%=13U%=11d%=11d%=12s",
 958                          segment_manager_index (sm),
 959                          sm->app_wrk_index, pool_elts (sm->segments),
 960                          format_memory_size, max_fifo_size,
 961                          sm->high_watermark, sm->low_watermark,
 962                          custom_logic ? "custom" : "none");
 963       }
 964       /* *INDENT-ON* */
 965
 966       vlib_cli_output (vm, "\n");
 967     }
 968   if (show_segments)
 969     {
 970       vlib_cli_output (vm, "%U", format_fifo_segment, 0, verbose);
 971
 972       /* *INDENT-OFF* */
 973       pool_foreach (sm, smm->segment_managers)  {
 974           segment_manager_foreach_segment_w_lock (seg, sm, ({
 975             vlib_cli_output (vm, "%U", format_fifo_segment, seg, verbose);
 976           }));
 977       }
 978       /* *INDENT-ON* */
 979
 980     }
 981   return 0;
 982 }
 983
 984 /* *INDENT-OFF* */
 985 VLIB_CLI_COMMAND (segment_manager_show_command, static) =
 986 {
 987   .path = "show segment-manager",
 988   .short_help = "show segment-manager [segments][verbose]",
 989   .function = segment_manager_show_fn,
 990 };
 991 /* *INDENT-ON* */
 992
 993 void
 994 segment_manager_format_sessions (segment_manager_t * sm, int verbose)
 995 {
 996   vlib_main_t *vm = vlib_get_main ();
 997   app_worker_t *app_wrk;
 998   fifo_segment_t *fs;
 999   const u8 *app_name;
1000   int slice_index;
1001   u8 *s = 0, *str;
1002   svm_fifo_t *f;
1003
1004   if (!sm)
1005     {
1006       if (verbose)
1007         vlib_cli_output (vm, "%-40s%-20s%-15s%-10s", "Connection", "App",
1008                          "API Client", "SegManager");
1009       else
1010         vlib_cli_output (vm, "%-40s%-20s", "Connection", "App");
1011       return;
1012     }
1013
1014   app_wrk = app_worker_get (sm->app_wrk_index);
1015   app_name = application_name_from_index (app_wrk->app_index);
1016
1017   clib_rwlock_reader_lock (&sm->segments_rwlock);
1018
1019   /* *INDENT-OFF* */
1020   pool_foreach (fs, sm->segments)  {
1021     for (slice_index = 0; slice_index < fs->n_slices; slice_index++)
1022       {
1023         f = fifo_segment_get_slice_fifo_list (fs, slice_index);
1024         while (f)
1025           {
1026             u32 session_index, thread_index;
1027             session_t *session;
1028
1029             session_index = f->shr->master_session_index;
1030             thread_index = f->master_thread_index;
1031
1032             session = session_get (session_index, thread_index);
1033             str = format (0, "%U", format_session, session, verbose);
1034
1035             if (verbose)
1036               s = format (s, "%-40v%-20v%-15u%-10u", str, app_name,
1037                           app_wrk->api_client_index,
1038                           app_wrk->connects_seg_manager);
1039             else
1040               s = format (s, "%-40v%-20v", str, app_name);
1041
1042             vlib_cli_output (vm, "%v", s);
1043             vec_reset_length (s);
1044             vec_free (str);
1045
1046             f = f->next;
1047           }
1048         vec_free (s);
1049       }
1050   }
1051   /* *INDENT-ON* */
1052
1053   clib_rwlock_reader_unlock (&sm->segments_rwlock);
1054 }
1055
1056 void
1057 segment_manager_set_watermarks (segment_manager_t * sm,
1058                                 u8 high_watermark, u8 low_watermark)
1059 {
1060   ASSERT (high_watermark <= 100 && low_watermark <= 100 &&
1061           low_watermark <= high_watermark);
1062
1063   sm->high_watermark = high_watermark;
1064   sm->low_watermark = low_watermark;
1065 }
1066
1067 /*
1068  * fd.io coding-style-patch-verification: ON
1069  *
1070  * Local Variables:
1071  * eval: (c-set-style "gnu")
1072  * End:
1073  */