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