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All of the redrawings were made by me except images/c_user/states which was made by LukaMag. This patch serves to update all the images. This work was part of GCI 2018.
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1.5 KiB
ReStructuredText
36 lines
1.5 KiB
ReStructuredText
.. comment SPDX-License-Identifier: CC-BY-SA-4.0
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.. COMMENT: Written by Eric Norum
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.. COMMENT: COPYRIGHT (c) 1988-2002.
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.. COMMENT: On-Line Applications Research Corporation (OAR).
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.. COMMENT: All rights reserved.
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Network Task Structure and Data Flow
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####################################
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A schematic diagram of the tasks and message *mbuf* queues in a simple RTEMS
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networking application is shown in the following figure:
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.. figure:: ../images/networking/networkflow.png
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:align: center
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:alt: Network Flow
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The transmit task for each network interface is normally blocked waiting for a
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packet to arrive in the transmit queue. Once a packet arrives, the transmit
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task may block waiting for an event from the transmit interrupt handler. The
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transmit interrupt handler sends an RTEMS event to the transmit task to
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indicate that transmit hardware resources have become available.
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The receive task for each network interface is normally blocked waiting for an
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event from the receive interrupt handler. When this event is received the
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receive task reads the packet and forwards it to the network stack for
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subsequent processing by the network task.
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The network task processes incoming packets and takes care of timed operations
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such as handling TCP timeouts and aging and removing routing table entries.
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The 'Network code' contains routines which may run in the context of the user
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application tasks, the interface receive task or the network task. A network
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semaphore ensures that the data structures manipulated by the network code
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remain consistent.
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