Changeset 4d74cbd in rtems-docs


Ignore:
Timestamp:
Mar 9, 2020, 7:50:59 AM (4 months ago)
Author:
Sebastian Huber <sebastian.huber@…>
Branches:
5, master
Children:
c0a70db
Parents:
bdd17e5
git-author:
Sebastian Huber <sebastian.huber@…> (03/09/20 07:50:59)
git-committer:
Sebastian Huber <sebastian.huber@…> (03/12/20 09:18:14)
Message:

c-user: Move "Message Queue Buffer Configuration"

Update #3836.

Location:
c-user/config
Files:
1 added
1 edited

Legend:

Unmodified
Added
Removed
  • c-user/config/index.rst

    rbdd17e5 r4d74cbd  
    1919    posix-init-thread
    2020    task-stack-alloc
    21 
    22 Message Queue Buffer Configuration
    23 ==================================
    24 
    25 This section describes the configuration parameters related to specifying the
    26 amount of memory reserved for message queue message buffers.  See
    27 :ref:`CONFIGURE_MAXIMUM_MESSAGE_QUEUES` and
    28 :ref:`CONFIGURE_MAXIMUM_POSIX_MESSAGE_QUEUES`.
    29 
    30 .. index:: CONFIGURE_MESSAGE_BUFFER_MEMORY
    31 .. index:: configure message queue buffer memory
    32 
    33 .. _CONFIGURE_MESSAGE_BUFFER_MEMORY:
    34 
    35 CONFIGURE_MESSAGE_BUFFER_MEMORY
    36 -------------------------------
    37 
    38 CONSTANT:
    39     ``CONFIGURE_MESSAGE_BUFFER_MEMORY``
    40 
    41 DATA TYPE:
    42     integer summation macro
    43 
    44 RANGE:
    45     undefined (zero) or calculation resulting in a positive integer
    46 
    47 DEFAULT VALUE:
    48     This is not defined by default, and zero (0) memory is reserved.
    49 
    50 DESCRIPTION:
    51     This macro is set to the number of bytes the application requires to be
    52     reserved for pending Classic API Message Queue buffers.
    53 
    54 NOTES:
    55     The following illustrates how the help macro
    56     :ref:`CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE` can be used to assist in
    57     calculating the message buffer memory required.  In this example, there are
    58     two message queues used in this application.  The first message queue has
    59     maximum of 24 pending messages with the message structure defined by the
    60     type ``one_message_type``.  The other message queue has maximum of 500
    61     pending messages with the message structure defined by the type
    62     ``other_message_type``.
    63 
    64     .. code-block:: c
    65 
    66         #define CONFIGURE_MESSAGE_BUFFER_MEMORY \
    67                     (CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE( \
    68                          24, sizeof(one_message_type) \
    69                      ) + \
    70                      CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE( \
    71                          500, sizeof(other_message_type) \
    72                      )
    73 
    74 .. index:: CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE
    75 .. index:: memory for a single message queue's buffers
    76 
    77 .. _CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE:
    78 
    79 CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE
    80 -----------------------------------
    81 
    82 CONSTANT:
    83     ``CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE(max_messages, size_per)``
    84 
    85 DATA TYPE:
    86     Unsigned integer (``size_t``).
    87 
    88 RANGE:
    89     Positive.
    90 
    91 DEFAULT VALUE:
    92     The default value is None.
    93 
    94 DESCRIPTION:
    95     This is a helper macro which is used to assist in computing the total
    96     amount of memory required for message buffers.  Each message queue will
    97     have its own configuration with maximum message size and maximum number of
    98     pending messages.
    99 
    100     The interface for this macro is as follows:
    101 
    102     .. code-block:: c
    103 
    104         CONFIGURE_MESSAGE_BUFFERS_FOR_QUEUE(max_messages, size_per)
    105 
    106     Where ``max_messages`` is the maximum number of pending messages and
    107     ``size_per`` is the size in bytes of the user message.
    108 
    109 NOTES:
    110     This macro is only used in support of :ref:`CONFIGURE_MESSAGE_BUFFER_MEMORY`.
     21    msg-queue-buffer
    11122
    11223Filesystem Configuration
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