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 {
  93   segment_manager_main_t *smm = &sm_main;
  94   segment_manager_props_t *props;
  95   fifo_segment_t *fs;
  96   u32 fs_index = ~0;
  97   u8 *seg_name;
  98   int rv;
  99
 100   props = segment_manager_properties_get (sm);
 101
 102   /* Not configured for addition of new segments and not first */
 103   if (!props->add_segment && !segment_size)
 104     {
 105       clib_warning ("cannot allocate new segment");
 106       return VNET_API_ERROR_INVALID_VALUE;
 107     }
 108
 109   /*
 110    * Allocate fifo segment and grab lock if needed
 111    */
 112   if (vlib_num_workers ())
 113     clib_rwlock_writer_lock (&sm->segments_rwlock);
 114
 115   pool_get_zero (sm->segments, fs);
 116
 117   /*
 118    * Allocate ssvm segment
 119    */
 120   segment_size = segment_size ? segment_size : props->add_segment_size;
 121   segment_size = round_pow2 (segment_size, clib_mem_get_page_size ());
 122
 123   if (props->segment_type != SSVM_SEGMENT_PRIVATE)
 124     {
 125       seg_name = format (0, "%d-%d%c", getpid (), smm->seg_name_counter++, 0);
 126     }
 127   else
 128     {
 129       app_worker_t *app_wrk = app_worker_get (sm->app_wrk_index);
 130       application_t *app = application_get (app_wrk->app_index);
 131       seg_name = format (0, "%v segment%c", app->name, 0);
 132     }
 133
 134   fs->ssvm.ssvm_size = segment_size;
 135   fs->ssvm.name = seg_name;
 136   fs->ssvm.requested_va = 0;
 137
 138   if ((rv = ssvm_server_init (&fs->ssvm, props->segment_type)))
 139     {
 140       clib_warning ("svm_master_init ('%v', %u) failed", seg_name,
 141                     segment_size);
 142       pool_put (sm->segments, fs);
 143       goto done;
 144     }
 145
 146   /*
 147    * Initialize fifo segment
 148    */
 149   fs->n_slices = props->n_slices;
 150   fifo_segment_init (fs);
 151
 152   /*
 153    * Save segment index before dropping lock, if any held
 154    */
 155   fs_index = fs - sm->segments;
 156
 157   /*
 158    * Set watermarks in segment
 159    */
 160   fs->h->high_watermark = sm->high_watermark;
 161   fs->h->low_watermark = sm->low_watermark;
 162   fs->h->pct_first_alloc = props->pct_first_alloc;
 163   fs->h->flags &= ~FIFO_SEGMENT_F_MEM_LIMIT;
 164
 165 done:
 166
 167   if (vlib_num_workers ())
 168     clib_rwlock_writer_unlock (&sm->segments_rwlock);
 169
 170   return fs_index;
 171 }
 172
 173 /**
 174  * Remove segment without lock
 175  */
 176 void
 177 segment_manager_del_segment (segment_manager_t * sm, fifo_segment_t * fs)
 178 {
 179   if (ssvm_type (&fs->ssvm) != SSVM_SEGMENT_PRIVATE)
 180     {
 181       if (!segment_manager_app_detached (sm))
 182         {
 183           app_worker_t *app_wrk;
 184           u64 segment_handle;
 185           app_wrk = app_worker_get (sm->app_wrk_index);
 186           segment_handle = segment_manager_segment_handle (sm, fs);
 187           app_worker_del_segment_notify (app_wrk, segment_handle);
 188         }
 189     }
 190
 191   fifo_segment_cleanup (fs);
 192   ssvm_delete (&fs->ssvm);
 193
 194   if (CLIB_DEBUG)
 195     clib_memset (fs, 0xfb, sizeof (*fs));
 196   pool_put (sm->segments, fs);
 197 }
 198
 199 static fifo_segment_t *
 200 segment_manager_get_segment_if_valid (segment_manager_t * sm,
 201                                       u32 segment_index)
 202 {
 203   if (pool_is_free_index (sm->segments, segment_index))
 204     return 0;
 205   return pool_elt_at_index (sm->segments, segment_index);
 206 }
 207
 208 /**
 209  * Removes segment after acquiring writer lock
 210  */
 211 static inline void
 212 sm_lock_and_del_segment_inline (segment_manager_t * sm, u32 fs_index)
 213 {
 214   fifo_segment_t *fs;
 215   u8 is_prealloc;
 216
 217   clib_rwlock_writer_lock (&sm->segments_rwlock);
 218
 219   fs = segment_manager_get_segment_if_valid (sm, fs_index);
 220   if (!fs)
 221     goto done;
 222
 223   is_prealloc = fifo_segment_flags (fs) & FIFO_SEGMENT_F_IS_PREALLOCATED;
 224   if (is_prealloc && !segment_manager_app_detached (sm))
 225     goto done;
 226
 227   segment_manager_del_segment (sm, fs);
 228
 229 done:
 230   clib_rwlock_writer_unlock (&sm->segments_rwlock);
 231 }
 232
 233 void
 234 segment_manager_lock_and_del_segment (segment_manager_t * sm, u32 fs_index)
 235 {
 236   sm_lock_and_del_segment_inline (sm, fs_index);
 237 }
 238
 239 /**
 240  * Reads a segment from the segment manager's pool without lock
 241  */
 242 fifo_segment_t *
 243 segment_manager_get_segment (segment_manager_t * sm, u32 segment_index)
 244 {
 245   return pool_elt_at_index (sm->segments, segment_index);
 246 }
 247
 248 u64
 249 segment_manager_segment_handle (segment_manager_t * sm,
 250                                 fifo_segment_t * segment)
 251 {
 252   u32 segment_index = segment_manager_segment_index (sm, segment);
 253   return (((u64) segment_manager_index (sm) << 32) | segment_index);
 254 }
 255
 256 u64
 257 segment_manager_make_segment_handle (u32 segment_manager_index,
 258                                      u32 segment_index)
 259 {
 260   return (((u64) segment_manager_index << 32) | segment_index);
 261 }
 262
 263 fifo_segment_t *
 264 segment_manager_get_segment_w_handle (u64 segment_handle)
 265 {
 266   u32 sm_index, segment_index;
 267   segment_manager_t *sm;
 268
 269   segment_manager_parse_segment_handle (segment_handle, &sm_index,
 270                                         &segment_index);
 271   sm = segment_manager_get (sm_index);
 272   if (!sm || pool_is_free_index (sm->segments, segment_index))
 273     return 0;
 274   return pool_elt_at_index (sm->segments, segment_index);
 275 }
 276
 277 /**
 278  * Reads a segment from the segment manager's pool and acquires reader lock
 279  *
 280  * Caller must drop the reader's lock by calling
 281  * @ref segment_manager_segment_reader_unlock once it finishes working with
 282  * the segment.
 283  */
 284 fifo_segment_t *
 285 segment_manager_get_segment_w_lock (segment_manager_t * sm, u32 segment_index)
 286 {
 287   clib_rwlock_reader_lock (&sm->segments_rwlock);
 288   return pool_elt_at_index (sm->segments, segment_index);
 289 }
 290
 291 void
 292 segment_manager_segment_reader_lock (segment_manager_t * sm)
 293 {
 294   clib_rwlock_reader_lock (&sm->segments_rwlock);
 295 }
 296
 297 void
 298 segment_manager_segment_reader_unlock (segment_manager_t * sm)
 299 {
 300   clib_rwlock_reader_unlock (&sm->segments_rwlock);
 301 }
 302
 303 void
 304 segment_manager_segment_writer_unlock (segment_manager_t * sm)
 305 {
 306   clib_rwlock_writer_unlock (&sm->segments_rwlock);
 307 }
 308
 309 segment_manager_t *
 310 segment_manager_alloc (void)
 311 {
 312   segment_manager_main_t *smm = &sm_main;
 313   segment_manager_t *sm;
 314
 315   pool_get_zero (smm->segment_managers, sm);
 316   clib_rwlock_init (&sm->segments_rwlock);
 317   return sm;
 318 }
 319
 320 int
 321 segment_manager_init (segment_manager_t * sm)
 322 {
 323   segment_manager_props_t *props;
 324
 325   props = segment_manager_properties_get (sm);
 326
 327   sm->max_fifo_size = props->max_fifo_size ?
 328     props->max_fifo_size : sm_main.default_max_fifo_size;
 329   sm->max_fifo_size = clib_max (sm->max_fifo_size, 4096);
 330
 331   segment_manager_set_watermarks (sm,
 332                                   props->high_watermark,
 333                                   props->low_watermark);
 334   return 0;
 335 }
 336
 337 /**
 338  * Initializes segment manager based on options provided.
 339  * Returns error if ssvm segment(s) allocation fails.
 340  */
 341 int
 342 segment_manager_init_first (segment_manager_t * sm)
 343 {
 344   segment_manager_props_t *props;
 345   uword first_seg_size;
 346   fifo_segment_t *fs;
 347   int fs_index, i;
 348
 349   segment_manager_init (sm);
 350   props = segment_manager_properties_get (sm);
 351   first_seg_size = clib_max (props->segment_size,
 352                              sm_main.default_segment_size);
 353
 354   if (props->prealloc_fifos)
 355     {
 356       u64 approx_total_size, max_seg_size = ((u64) 1 << 32) - (128 << 10);
 357       u32 rx_rounded_data_size, tx_rounded_data_size;
 358       u32 prealloc_fifo_pairs = props->prealloc_fifos;
 359       u32 rx_fifo_size, tx_fifo_size, pair_size;
 360       u32 approx_segment_count;
 361
 362       /* Figure out how many segments should be preallocated */
 363       rx_rounded_data_size = (1 << (max_log2 (props->rx_fifo_size)));
 364       tx_rounded_data_size = (1 << (max_log2 (props->tx_fifo_size)));
 365
 366       rx_fifo_size = sizeof (svm_fifo_t) + rx_rounded_data_size;
 367       tx_fifo_size = sizeof (svm_fifo_t) + tx_rounded_data_size;
 368       pair_size = rx_fifo_size + tx_fifo_size;
 369
 370       approx_total_size = (u64) prealloc_fifo_pairs *pair_size;
 371       if (first_seg_size > approx_total_size)
 372         max_seg_size = first_seg_size;
 373       approx_segment_count = (approx_total_size + (max_seg_size - 1))
 374         / max_seg_size;
 375
 376       /* Allocate the segments */
 377       for (i = 0; i < approx_segment_count + 1; i++)
 378         {
 379           fs_index = segment_manager_add_segment (sm, max_seg_size);
 380           if (fs_index < 0)
 381             {
 382               clib_warning ("Failed to preallocate segment %d", i);
 383               return fs_index;
 384             }
 385
 386           fs = segment_manager_get_segment (sm, fs_index);
 387           if (i == 0)
 388             sm->event_queue = segment_manager_alloc_queue (fs, props);
 389
 390           fifo_segment_preallocate_fifo_pairs (fs,
 391                                                props->rx_fifo_size,
 392                                                props->tx_fifo_size,
 393                                                &prealloc_fifo_pairs);
 394           fifo_segment_flags (fs) = FIFO_SEGMENT_F_IS_PREALLOCATED;
 395           if (prealloc_fifo_pairs == 0)
 396             break;
 397         }
 398       return 0;
 399     }
 400
 401   fs_index = segment_manager_add_segment (sm, first_seg_size);
 402   if (fs_index < 0)
 403     {
 404       clib_warning ("Failed to allocate segment");
 405       return fs_index;
 406     }
 407
 408   fs = segment_manager_get_segment (sm, fs_index);
 409   sm->event_queue = segment_manager_alloc_queue (fs, props);
 410
 411   if (props->prealloc_fifo_hdrs)
 412     {
 413       u32 hdrs_per_slice;
 414
 415       /* Do not preallocate on slice associated to main thread */
 416       i = (vlib_num_workers ()? 1 : 0);
 417       hdrs_per_slice = props->prealloc_fifo_hdrs / (fs->n_slices - i);
 418
 419       for (; i < fs->n_slices; i++)
 420         {
 421           if (fifo_segment_prealloc_fifo_hdrs (fs, i, hdrs_per_slice))
 422             return VNET_API_ERROR_SVM_SEGMENT_CREATE_FAIL;
 423         }
 424     }
 425
 426   return 0;
 427 }
 428
 429 void
 430 segment_manager_cleanup_detached_listener (segment_manager_t * sm)
 431 {
 432   app_worker_t *app_wrk;
 433
 434   app_wrk = app_worker_get_if_valid (sm->app_wrk_index);
 435   if (!app_wrk)
 436     return;
 437
 438   app_worker_del_detached_sm (app_wrk, segment_manager_index (sm));
 439 }
 440
 441 /**
 442  * Cleanup segment manager.
 443  */
 444 void
 445 segment_manager_free (segment_manager_t * sm)
 446 {
 447   segment_manager_main_t *smm = &sm_main;
 448   fifo_segment_t *fifo_segment;
 449
 450   ASSERT (vlib_get_thread_index () == 0
 451           && !segment_manager_has_fifos (sm)
 452           && segment_manager_app_detached (sm));
 453
 454   if (sm->flags & SEG_MANAGER_F_DETACHED_LISTENER)
 455     segment_manager_cleanup_detached_listener (sm);
 456
 457   /* If we have empty preallocated segments that haven't been removed, remove
 458    * them now. Apart from that, the first segment in the first segment manager
 459    * is not removed when all fifos are removed. It can only be removed when
 460    * the manager is explicitly deleted/detached by the app. */
 461   clib_rwlock_writer_lock (&sm->segments_rwlock);
 462
 463   /* *INDENT-OFF* */
 464   pool_foreach (fifo_segment, sm->segments)  {
 465     segment_manager_del_segment (sm, fifo_segment);
 466   }
 467   /* *INDENT-ON* */
 468
 469   pool_free (sm->segments);
 470   clib_rwlock_writer_unlock (&sm->segments_rwlock);
 471
 472   clib_rwlock_free (&sm->segments_rwlock);
 473   if (CLIB_DEBUG)
 474     clib_memset (sm, 0xfe, sizeof (*sm));
 475   pool_put (smm->segment_managers, sm);
 476 }
 477
 478 static void
 479 sm_free_w_index_helper (void *arg)
 480 {
 481   u32 sm_index = *(u32 *) arg;
 482   segment_manager_t *sm;
 483
 484   ASSERT (vlib_get_thread_index () == 0);
 485
 486   if ((sm = segment_manager_get_if_valid (sm_index)))
 487     segment_manager_free (sm);
 488 }
 489
 490 static void
 491 segment_manager_free_safe (segment_manager_t * sm)
 492 {
 493   if (!vlib_thread_is_main_w_barrier ())
 494     {
 495       u32 sm_index = segment_manager_index (sm);
 496       vlib_rpc_call_main_thread (sm_free_w_index_helper, (u8 *) & sm_index,
 497                                  sizeof (sm_index));
 498     }
 499   else
 500     {
 501       segment_manager_free (sm);
 502     }
 503 }
 504
 505 void
 506 segment_manager_init_free (segment_manager_t * sm)
 507 {
 508   ASSERT (vlib_get_thread_index () == 0);
 509
 510   segment_manager_app_detach (sm);
 511   if (segment_manager_has_fifos (sm))
 512     segment_manager_del_sessions (sm);
 513   else
 514     {
 515       ASSERT (!sm->first_is_protected || segment_manager_app_detached (sm));
 516       segment_manager_free (sm);
 517     }
 518 }
 519
 520 segment_manager_t *
 521 segment_manager_get (u32 index)
 522 {
 523   return pool_elt_at_index (sm_main.segment_managers, index);
 524 }
 525
 526 segment_manager_t *
 527 segment_manager_get_if_valid (u32 index)
 528 {
 529   if (pool_is_free_index (sm_main.segment_managers, index))
 530     return 0;
 531   return pool_elt_at_index (sm_main.segment_managers, index);
 532 }
 533
 534 u32
 535 segment_manager_index (segment_manager_t * sm)
 536 {
 537   return sm - sm_main.segment_managers;
 538 }
 539
 540 u8
 541 segment_manager_has_fifos (segment_manager_t * sm)
 542 {
 543   fifo_segment_t *seg;
 544   u8 first = 1;
 545
 546   /* *INDENT-OFF* */
 547   segment_manager_foreach_segment_w_lock (seg, sm, ({
 548     if (CLIB_DEBUG && !first && !fifo_segment_has_fifos (seg)
 549         && !(fifo_segment_flags (seg) & FIFO_SEGMENT_F_IS_PREALLOCATED))
 550       {
 551         clib_warning ("segment %d has no fifos!",
 552                       segment_manager_segment_index (sm, seg));
 553         first = 0;
 554       }
 555     if (fifo_segment_has_fifos (seg))
 556       {
 557         segment_manager_segment_reader_unlock (sm);
 558         return 1;
 559       }
 560   }));
 561   /* *INDENT-ON* */
 562
 563   return 0;
 564 }
 565
 566 /**
 567  * Initiate disconnects for all sessions 'owned' by a segment manager
 568  */
 569 void
 570 segment_manager_del_sessions (segment_manager_t * sm)
 571 {
 572   session_handle_t *handles = 0, *handle;
 573   fifo_segment_t *fs;
 574   session_t *session;
 575   int slice_index;
 576   svm_fifo_t *f;
 577
 578   ASSERT (pool_elts (sm->segments) != 0);
 579
 580   /* Across all fifo segments used by the server */
 581   /* *INDENT-OFF* */
 582   segment_manager_foreach_segment_w_lock (fs, sm, ({
 583     for (slice_index = 0; slice_index < fs->n_slices; slice_index++)
 584       {
 585         f = fifo_segment_get_slice_fifo_list (fs, slice_index);
 586
 587         /*
 588          * Remove any residual sessions from the session lookup table
 589          * Don't bother deleting the individual fifos, we're going to
 590          * throw away the fifo segment in a minute.
 591          */
 592         while (f)
 593           {
 594             session = session_get_if_valid (f->shr->master_session_index,
 595                                             f->master_thread_index);
 596             if (session)
 597               vec_add1 (handles, session_handle (session));
 598             f = f->next;
 599           }
 600       }
 601
 602     /* Instead of removing the segment, test when cleaning up disconnected
 603      * sessions if the segment can be removed.
 604      */
 605   }));
 606   /* *INDENT-ON* */
 607
 608   vec_foreach (handle, handles)
 609   {
 610     session = session_get_from_handle (*handle);
 611     session_close (session);
 612     /* Avoid propagating notifications back to the app */
 613     session->app_wrk_index = APP_INVALID_INDEX;
 614   }
 615   vec_free (handles);
 616 }
 617
 618 int
 619 segment_manager_try_alloc_fifos (fifo_segment_t * fifo_segment,
 620                                  u32 thread_index,
 621                                  u32 rx_fifo_size, u32 tx_fifo_size,
 622                                  svm_fifo_t ** rx_fifo, svm_fifo_t ** tx_fifo)
 623 {
 624   rx_fifo_size = clib_max (rx_fifo_size, sm_main.default_fifo_size);
 625   *rx_fifo = fifo_segment_alloc_fifo_w_slice (fifo_segment, thread_index,
 626                                               rx_fifo_size,
 627                                               FIFO_SEGMENT_RX_FIFO);
 628
 629   tx_fifo_size = clib_max (tx_fifo_size, sm_main.default_fifo_size);
 630   *tx_fifo = fifo_segment_alloc_fifo_w_slice (fifo_segment, thread_index,
 631                                               tx_fifo_size,
 632                                               FIFO_SEGMENT_TX_FIFO);
 633
 634   if (*rx_fifo == 0)
 635     {
 636       /* This would be very odd, but handle it... */
 637       if (*tx_fifo != 0)
 638         {
 639           fifo_segment_free_fifo (fifo_segment, *tx_fifo);
 640           *tx_fifo = 0;
 641         }
 642       return -1;
 643     }
 644   if (*tx_fifo == 0)
 645     {
 646       if (*rx_fifo != 0)
 647         {
 648           fifo_segment_free_fifo (fifo_segment, *rx_fifo);
 649           *rx_fifo = 0;
 650         }
 651       return -1;
 652     }
 653
 654   return 0;
 655 }
 656
 657 int
 658 segment_manager_alloc_session_fifos (segment_manager_t * sm,
 659                                      u32 thread_index,
 660                                      svm_fifo_t ** rx_fifo,
 661                                      svm_fifo_t ** tx_fifo)
 662 {
 663   int alloc_fail = 1, rv = 0, new_fs_index;
 664   uword free_bytes, max_free_bytes = 0;
 665   segment_manager_props_t *props;
 666   fifo_segment_t *fs = 0, *cur;
 667   u32 sm_index, fs_index;
 668   u8 added_a_segment = 0;
 669   u64 fs_handle;
 670
 671   props = segment_manager_properties_get (sm);
 672
 673   /*
 674    * Find the first free segment to allocate the fifos in
 675    */
 676
 677   segment_manager_segment_reader_lock (sm);
 678
 679   /* *INDENT-OFF* */
 680   pool_foreach (cur, sm->segments)  {
 681     free_bytes = fifo_segment_available_bytes (cur);
 682     if (free_bytes > max_free_bytes)
 683       {
 684         max_free_bytes = free_bytes;
 685         fs = cur;
 686       }
 687   }
 688   /* *INDENT-ON* */
 689
 690   if (fs)
 691     {
 692       alloc_fail = segment_manager_try_alloc_fifos (fs, thread_index,
 693                                                     props->rx_fifo_size,
 694                                                     props->tx_fifo_size,
 695                                                     rx_fifo, tx_fifo);
 696       /* On success, keep lock until fifos are initialized */
 697       if (!alloc_fail)
 698         goto alloc_success;
 699     }
 700
 701   segment_manager_segment_reader_unlock (sm);
 702
 703 alloc_check:
 704
 705   if (!alloc_fail)
 706     {
 707
 708     alloc_success:
 709
 710       ASSERT (rx_fifo && tx_fifo);
 711       sm_index = segment_manager_index (sm);
 712       fs_index = segment_manager_segment_index (sm, fs);
 713       (*tx_fifo)->segment_manager = sm_index;
 714       (*rx_fifo)->segment_manager = sm_index;
 715       (*tx_fifo)->segment_index = fs_index;
 716       (*rx_fifo)->segment_index = fs_index;
 717
 718       if (added_a_segment)
 719         {
 720           app_worker_t *app_wrk;
 721           fs_handle = segment_manager_segment_handle (sm, fs);
 722           app_wrk = app_worker_get (sm->app_wrk_index);
 723           rv = app_worker_add_segment_notify (app_wrk, fs_handle);
 724         }
 725       /* Drop the lock after app is notified */
 726       segment_manager_segment_reader_unlock (sm);
 727       return rv;
 728     }
 729
 730   /*
 731    * Allocation failed, see if we can add a new segment
 732    */
 733   if (props->add_segment)
 734     {
 735       if (added_a_segment)
 736         {
 737           clib_warning ("Added a segment, still can't allocate a fifo");
 738           segment_manager_segment_reader_unlock (sm);
 739           return SESSION_E_SEG_NO_SPACE2;
 740         }
 741       if ((new_fs_index = segment_manager_add_segment (sm, 0)) < 0)
 742         {
 743           clib_warning ("Failed to add new segment");
 744           return SESSION_E_SEG_CREATE;
 745         }
 746       fs = segment_manager_get_segment_w_lock (sm, new_fs_index);
 747       alloc_fail = segment_manager_try_alloc_fifos (fs, thread_index,
 748                                                     props->rx_fifo_size,
 749                                                     props->tx_fifo_size,
 750                                                     rx_fifo, tx_fifo);
 751       added_a_segment = 1;
 752       goto alloc_check;
 753     }
 754   else
 755     {
 756       SESSION_DBG ("Can't add new seg and no space to allocate fifos!");
 757       return SESSION_E_SEG_NO_SPACE;
 758     }
 759 }
 760
 761 void
 762 segment_manager_dealloc_fifos (svm_fifo_t * rx_fifo, svm_fifo_t * tx_fifo)
 763 {
 764   segment_manager_t *sm;
 765   fifo_segment_t *fs;
 766   u32 segment_index;
 767
 768   if (!rx_fifo || !tx_fifo)
 769     return;
 770
 771   /* It's possible to have no segment manager if the session was removed
 772    * as result of a detach. */
 773   if (!(sm = segment_manager_get_if_valid (rx_fifo->segment_manager)))
 774     return;
 775
 776   segment_index = rx_fifo->segment_index;
 777   fs = segment_manager_get_segment_w_lock (sm, segment_index);
 778   fifo_segment_free_fifo (fs, rx_fifo);
 779   fifo_segment_free_fifo (fs, tx_fifo);
 780
 781   /*
 782    * Try to remove svm segment if it has no fifos. This can be done only if
 783    * the segment is not the first in the segment manager or if it is first
 784    * and it is not protected. Moreover, if the segment is first and the app
 785    * has detached from the segment manager, remove the segment manager.
 786    */
 787   if (!fifo_segment_has_fifos (fs))
 788     {
 789       segment_manager_segment_reader_unlock (sm);
 790
 791       /* Remove segment if it holds no fifos or first but not protected */
 792       if (segment_index != 0 || !sm->first_is_protected)
 793         sm_lock_and_del_segment_inline (sm, segment_index);
 794
 795       /* Remove segment manager if no sessions and detached from app */
 796       if (segment_manager_app_detached (sm)
 797           && !segment_manager_has_fifos (sm))
 798         segment_manager_free_safe (sm);
 799     }
 800   else
 801     segment_manager_segment_reader_unlock (sm);
 802 }
 803
 804 void
 805 segment_manager_detach_fifo (segment_manager_t *sm, svm_fifo_t **f)
 806 {
 807   fifo_segment_t *fs;
 808
 809   fs = segment_manager_get_segment_w_lock (sm, (*f)->segment_index);
 810   fifo_segment_detach_fifo (fs, f);
 811   segment_manager_segment_reader_unlock (sm);
 812 }
 813
 814 void
 815 segment_manager_attach_fifo (segment_manager_t *sm, svm_fifo_t **f,
 816                              session_t *s)
 817 {
 818   fifo_segment_t *fs;
 819
 820   fs = segment_manager_get_segment_w_lock (sm, (*f)->segment_index);
 821   fifo_segment_attach_fifo (fs, f, s->thread_index);
 822   segment_manager_segment_reader_unlock (sm);
 823
 824   (*f)->shr->master_session_index = s->session_index;
 825   (*f)->master_thread_index = s->thread_index;
 826 }
 827
 828 u32
 829 segment_manager_evt_q_expected_size (u32 q_len)
 830 {
 831   u32 fifo_evt_size, notif_q_size, q_hdrs;
 832   u32 msg_q_sz, fifo_evt_ring_sz, session_ntf_ring_sz;
 833
 834   fifo_evt_size = 1 << max_log2 (sizeof (session_event_t));
 835   notif_q_size = clib_max (16, q_len >> 4);
 836
 837   msg_q_sz = q_len * sizeof (svm_msg_q_msg_t);
 838   fifo_evt_ring_sz = q_len * fifo_evt_size;
 839   session_ntf_ring_sz = notif_q_size * 256;
 840   q_hdrs = sizeof (svm_queue_t) + sizeof (svm_msg_q_t);
 841
 842   return (msg_q_sz + fifo_evt_ring_sz + session_ntf_ring_sz + q_hdrs);
 843 }
 844
 845 /**
 846  * Allocates shm queue in the first segment
 847  *
 848  * Must be called with lock held
 849  */
 850 svm_msg_q_t *
 851 segment_manager_alloc_queue (fifo_segment_t * segment,
 852                              segment_manager_props_t * props)
 853 {
 854   u32 fifo_evt_size, session_evt_size = 256, notif_q_size;
 855   svm_msg_q_cfg_t _cfg, *cfg = &_cfg;
 856   svm_msg_q_t *q;
 857
 858   fifo_evt_size = sizeof (session_event_t);
 859   notif_q_size = clib_max (16, props->evt_q_size >> 4);
 860   /* *INDENT-OFF* */
 861   svm_msg_q_ring_cfg_t rc[SESSION_MQ_N_RINGS] = {
 862     {props->evt_q_size, fifo_evt_size, 0},
 863     {notif_q_size, session_evt_size, 0}
 864   };
 865   /* *INDENT-ON* */
 866   cfg->consumer_pid = 0;
 867   cfg->n_rings = 2;
 868   cfg->q_nitems = props->evt_q_size;
 869   cfg->ring_cfgs = rc;
 870
 871   q = fifo_segment_msg_q_alloc (segment, 0, cfg);
 872
 873   if (props->use_mq_eventfd)
 874     {
 875       if (svm_msg_q_alloc_eventfd (q))
 876         clib_warning ("failed to alloc eventfd");
 877     }
 878   return q;
 879 }
 880
 881 svm_msg_q_t *
 882 segment_manager_event_queue (segment_manager_t * sm)
 883 {
 884   return sm->event_queue;
 885 }
 886
 887 /**
 888  * Frees shm queue allocated in the first segment
 889  */
 890 void
 891 segment_manager_dealloc_queue (segment_manager_t * sm, svm_queue_t * q)
 892 {
 893   fifo_segment_t *segment;
 894   ssvm_shared_header_t *sh;
 895   void *oldheap;
 896
 897   ASSERT (!pool_is_free_index (sm->segments, 0));
 898
 899   segment = segment_manager_get_segment_w_lock (sm, 0);
 900   sh = segment->ssvm.sh;
 901
 902   oldheap = ssvm_push_heap (sh);
 903   svm_queue_free (q);
 904   ssvm_pop_heap (oldheap);
 905   segment_manager_segment_reader_unlock (sm);
 906 }
 907
 908 /*
 909  * Init segment vm address allocator
 910  */
 911 void
 912 segment_manager_main_init (void)
 913 {
 914   segment_manager_main_t *sm = &sm_main;
 915
 916   sm->default_fifo_size = 1 << 12;
 917   sm->default_segment_size = 1 << 20;
 918   sm->default_app_mq_size = 128;
 919   sm->default_max_fifo_size = 4 << 20;
 920   sm->default_high_watermark = 80;
 921   sm->default_low_watermark = 50;
 922 }
 923
 924 static clib_error_t *
 925 segment_manager_show_fn (vlib_main_t * vm, unformat_input_t * input,
 926                          vlib_cli_command_t * cmd)
 927 {
 928   segment_manager_main_t *smm = &sm_main;
 929   u8 show_segments = 0, verbose = 0;
 930   uword max_fifo_size;
 931   segment_manager_t *sm;
 932   fifo_segment_t *seg;
 933   app_worker_t *app_wrk;
 934   application_t *app;
 935   u8 custom_logic;
 936
 937   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
 938     {
 939       if (unformat (input, "segments"))
 940         show_segments = 1;
 941       else if (unformat (input, "verbose"))
 942         verbose = 1;
 943       else
 944         return clib_error_return (0, "unknown input `%U'",
 945                                   format_unformat_error, input);
 946     }
 947   vlib_cli_output (vm, "%d segment managers allocated",
 948                    pool_elts (smm->segment_managers));
 949   if (verbose && pool_elts (smm->segment_managers))
 950     {
 951       vlib_cli_output (vm, "%-6s%=10s%=10s%=13s%=11s%=11s%=12s",
 952                        "Index", "AppIndex", "Segments", "MaxFifoSize",
 953                        "HighWater", "LowWater", "FifoTuning");
 954
 955       /* *INDENT-OFF* */
 956       pool_foreach (sm, smm->segment_managers)  {
 957         app_wrk = app_worker_get_if_valid (sm->app_wrk_index);
 958         app = app_wrk ? application_get (app_wrk->app_index) : 0;
 959         custom_logic = (app && (app->cb_fns.fifo_tuning_callback)) ? 1 : 0;
 960         max_fifo_size = sm->max_fifo_size;
 961
 962         vlib_cli_output (vm, "%-6d%=10d%=10d%=13U%=11d%=11d%=12s",
 963                          segment_manager_index (sm),
 964                          sm->app_wrk_index, pool_elts (sm->segments),
 965                          format_memory_size, max_fifo_size,
 966                          sm->high_watermark, sm->low_watermark,
 967                          custom_logic ? "custom" : "none");
 968       }
 969       /* *INDENT-ON* */
 970
 971       vlib_cli_output (vm, "\n");
 972     }
 973   if (show_segments)
 974     {
 975       vlib_cli_output (vm, "%U", format_fifo_segment, 0, verbose);
 976
 977       /* *INDENT-OFF* */
 978       pool_foreach (sm, smm->segment_managers)  {
 979           segment_manager_foreach_segment_w_lock (seg, sm, ({
 980             vlib_cli_output (vm, "%U", format_fifo_segment, seg, verbose);
 981           }));
 982       }
 983       /* *INDENT-ON* */
 984
 985     }
 986   return 0;
 987 }
 988
 989 /* *INDENT-OFF* */
 990 VLIB_CLI_COMMAND (segment_manager_show_command, static) =
 991 {
 992   .path = "show segment-manager",
 993   .short_help = "show segment-manager [segments][verbose]",
 994   .function = segment_manager_show_fn,
 995 };
 996 /* *INDENT-ON* */
 997
 998 void
 999 segment_manager_format_sessions (segment_manager_t * sm, int verbose)
1000 {
1001   vlib_main_t *vm = vlib_get_main ();
1002   app_worker_t *app_wrk;
1003   fifo_segment_t *fs;
1004   const u8 *app_name;
1005   int slice_index;
1006   u8 *s = 0, *str;
1007   svm_fifo_t *f;
1008
1009   if (!sm)
1010     {
1011       if (verbose)
1012         vlib_cli_output (vm, "%-40s%-20s%-15s%-10s", "Connection", "App",
1013                          "API Client", "SegManager");
1014       else
1015         vlib_cli_output (vm, "%-40s%-20s", "Connection", "App");
1016       return;
1017     }
1018
1019   app_wrk = app_worker_get (sm->app_wrk_index);
1020   app_name = application_name_from_index (app_wrk->app_index);
1021
1022   clib_rwlock_reader_lock (&sm->segments_rwlock);
1023
1024   /* *INDENT-OFF* */
1025   pool_foreach (fs, sm->segments)  {
1026     for (slice_index = 0; slice_index < fs->n_slices; slice_index++)
1027       {
1028         f = fifo_segment_get_slice_fifo_list (fs, slice_index);
1029         while (f)
1030           {
1031             u32 session_index, thread_index;
1032             session_t *session;
1033
1034             session_index = f->shr->master_session_index;
1035             thread_index = f->master_thread_index;
1036
1037             session = session_get (session_index, thread_index);
1038             str = format (0, "%U", format_session, session, verbose);
1039
1040             if (verbose)
1041               s = format (s, "%-40v%-20v%-15u%-10u", str, app_name,
1042                           app_wrk->api_client_index,
1043                           app_wrk->connects_seg_manager);
1044             else
1045               s = format (s, "%-40v%-20v", str, app_name);
1046
1047             vlib_cli_output (vm, "%v", s);
1048             vec_reset_length (s);
1049             vec_free (str);
1050
1051             f = f->next;
1052           }
1053         vec_free (s);
1054       }
1055   }
1056   /* *INDENT-ON* */
1057
1058   clib_rwlock_reader_unlock (&sm->segments_rwlock);
1059 }
1060
1061 void
1062 segment_manager_set_watermarks (segment_manager_t * sm,
1063                                 u8 high_watermark, u8 low_watermark)
1064 {
1065   ASSERT (high_watermark <= 100 && low_watermark <= 100 &&
1066           low_watermark <= high_watermark);
1067
1068   sm->high_watermark = high_watermark;
1069   sm->low_watermark = low_watermark;
1070 }
1071
1072 /*
1073  * fd.io coding-style-patch-verification: ON
1074  *
1075  * Local Variables:
1076  * eval: (c-set-style "gnu")
1077  * End:
1078  */