src/vnet/session/segment_manager.h

   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 #ifndef SRC_VNET_SESSION_SEGMENT_MANAGER_H_
  16 #define SRC_VNET_SESSION_SEGMENT_MANAGER_H_
  17
  18 #include <svm/message_queue.h>
  19 #include <vppinfra/lock.h>
  20 #include <vppinfra/valloc.h>
  21 #include <svm/fifo_segment.h>
  22
  23 typedef struct _segment_manager_props
  24 {
  25   u32 rx_fifo_size;                     /**< receive fifo size */
  26   u32 tx_fifo_size;                     /**< transmit fifo size */
  27   u32 evt_q_size;                       /**< event queue length */
  28   u32 prealloc_fifos;                   /**< preallocated fifo pairs */
  29   uword segment_size;                   /**< first segment size */
  30   uword add_segment_size;               /**< additional segment size */
  31   u8 add_segment:1;                     /**< can add new segments flag */
  32   u8 use_mq_eventfd:1;                  /**< use eventfds for mqs flag */
  33   u8 reserved:6;                        /**< reserved flags */
  34   u8 n_slices;                          /**< number of fs slices/threads */
  35   ssvm_segment_type_t segment_type;     /**< seg type: if set to SSVM_N_TYPES,
  36                                              private segments are used */
  37 } segment_manager_props_t;
  38
  39 typedef struct _segment_manager
  40 {
  41   /** Pool of segments allocated by this manager */
  42   fifo_segment_t *segments;
  43
  44   /** rwlock that protects the segments pool */
  45   clib_rwlock_t segments_rwlock;
  46
  47   /** Owner app worker index */
  48   u32 app_wrk_index;
  49
  50   /**
  51    * First segment should not be deleted unless segment manger is deleted.
  52    * This also indicates that the segment manager is the first to have been
  53    * allocated for the app.
  54    */
  55   u8 first_is_protected;
  56
  57   /**
  58    * App event queue allocated in first segment
  59    */
  60   svm_msg_q_t *event_queue;
  61 } segment_manager_t;
  62
  63 typedef struct segment_manager_main_init_args_
  64 {
  65   u64 baseva;
  66   u64 size;
  67 } segment_manager_main_init_args_t;
  68
  69 #define SEGMENT_MANAGER_INVALID_APP_INDEX ((u32) ~0)
  70
  71 segment_manager_t *segment_manager_alloc (void);
  72 int segment_manager_init (segment_manager_t * sm, uword first_seg_size,
  73                           u32 prealloc_fifo_pairs);
  74
  75 /**
  76  * Cleanup segment manager
  77  *
  78  * @param sm    segment manager to be freed
  79  */
  80 void segment_manager_free (segment_manager_t * sm);
  81
  82 /**
  83  * Initiate segment manager cleanup
  84  *
  85  * @param sm    segment manager to be freed
  86  */
  87 void segment_manager_init_free (segment_manager_t * sm);
  88 segment_manager_t *segment_manager_get (u32 index);
  89 segment_manager_t *segment_manager_get_if_valid (u32 index);
  90 u32 segment_manager_index (segment_manager_t * sm);
  91
  92 int segment_manager_add_segment (segment_manager_t * sm, uword segment_size);
  93 void segment_manager_del_segment (segment_manager_t * sm,
  94                                   fifo_segment_t * fs);
  95 fifo_segment_t *segment_manager_get_segment (segment_manager_t * sm,
  96                                              u32 segment_index);
  97 fifo_segment_t *segment_manager_get_segment_w_handle (u64 sh);
  98 fifo_segment_t *segment_manager_get_segment_w_lock (segment_manager_t * sm,
  99                                                     u32 segment_index);
 100 int segment_manager_add_first_segment (segment_manager_t * sm,
 101                                        u32 segment_size);
 102 u64 segment_manager_make_segment_handle (u32 segment_manager_index,
 103                                          u32 segment_index);
 104 u64 segment_manager_segment_handle (segment_manager_t * sm,
 105                                     fifo_segment_t * segment);
 106 void segment_manager_segment_reader_unlock (segment_manager_t * sm);
 107 void segment_manager_segment_writer_unlock (segment_manager_t * sm);
 108
 109 int segment_manager_alloc_session_fifos (segment_manager_t * sm,
 110                                          u32 thread_index,
 111                                          svm_fifo_t ** rx_fifo,
 112                                          svm_fifo_t ** tx_fifo);
 113 int segment_manager_try_alloc_fifos (fifo_segment_t * fs,
 114                                      u32 thread_index,
 115                                      u32 rx_fifo_size, u32 tx_fifo_size,
 116                                      svm_fifo_t ** rx_fifo,
 117                                      svm_fifo_t ** tx_fifo);
 118 void segment_manager_dealloc_fifos (svm_fifo_t * rx_fifo,
 119                                     svm_fifo_t * tx_fifo);
 120
 121 /**
 122  * Grows fifo owned by segment manager
 123  *
 124  * @param sm    segment manager that owns the fifo
 125  * @param f     fifo to be grown
 126  * @param size  amount of bytes to add to fifo
 127  * @return      0 on success, negative number otherwise
 128  */
 129 int segment_manager_grow_fifo (segment_manager_t * sm, svm_fifo_t * f,
 130                                u32 size);
 131
 132 /**
 133  * Request to shrink fifo owned by segment manager
 134  *
 135  * If this is not called by the producer, no attempt is made to reduce the
 136  * size until the producer tries to enqueue more data. To collect the chunks
 137  * that are to be removed call @ref segment_manager_collect_fifo_chunks
 138  *
 139  * Size reduction does not affect fifo chunk boundaries. Therefore chunks are
 140  * not split and the amount of bytes to be removed can be equal to or less
 141  * than what was requested.
 142  *
 143  * @param sm            segment manager that owns the fifo
 144  * @param f             fifo to be shrunk
 145  * @param size          amount of bytes to remove from fifo
 146  * @param is_producer   flag that indicates is caller is the producer for the
 147  *                      fifo.
 148  * @return              actual number of bytes to be removed
 149  */
 150 int segment_manager_shrink_fifo (segment_manager_t * sm, svm_fifo_t * f,
 151                                  u32 size, u8 is_producer);
 152
 153 /**
 154  * Collect fifo chunks that are no longer used
 155  *
 156  * This should not be called unless SVM_FIFO_F_COLLECT_CHUNKS is set for
 157  * the fifo. The chunks are returned to the fifo segment freelist.
 158  *
 159  * @param sm            segment manager that owns the fifo
 160  * @param f             fifo whose chunks are to be collected
 161  * @return              0 on success, error otherwise
 162  */
 163 int segment_manager_collect_fifo_chunks (segment_manager_t * sm,
 164                                          svm_fifo_t * f);
 165 u8 segment_manager_has_fifos (segment_manager_t * sm);
 166
 167 svm_msg_q_t *segment_manager_alloc_queue (fifo_segment_t * fs,
 168                                           segment_manager_props_t * props);
 169 void segment_manager_dealloc_queue (segment_manager_t * sm, svm_queue_t * q);
 170 svm_msg_q_t *segment_manager_event_queue (segment_manager_t * sm);
 171 u32 segment_manager_evt_q_expected_size (u32 q_size);
 172
 173 void segment_manager_app_detach (segment_manager_t * sm);
 174
 175 /**
 176  * Cleanup segment manager sessions
 177  *
 178  * Initiates disconnects for all sessions 'owned' by a segment manager by
 179  * leveraging the backpointers that fifos keep.
 180  *
 181  * @param sm    segment manager whose sessions are to be disconnected
 182  */
 183 void segment_manager_del_sessions (segment_manager_t * sm);
 184 void segment_manager_format_sessions (segment_manager_t * sm, int verbose);
 185
 186 void segment_manager_main_init (segment_manager_main_init_args_t * a);
 187
 188 segment_manager_props_t *segment_manager_props_init (segment_manager_props_t *
 189                                                      sm);
 190
 191 #endif /* SRC_VNET_SESSION_SEGMENT_MANAGER_H_ */
 192 /*
 193  * fd.io coding-style-patch-verification: ON
 194  *
 195  * Local Variables:
 196  * eval: (c-set-style "gnu")
 197  * End:
 198  */