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Nodes, menus, etc are automatically generated now

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This commit is contained in:
Joel Sherrill
1998-03-27 18:53:17 +00:00
parent 1f020c6577
commit 20515fc1f8
24 changed files with 130 additions and 1837 deletions
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169
doc/user/task.t
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@@ -6,24 +6,8 @@
@c $Id$
@c
@ifinfo
@node Task Manager, Task Manager Introduction, SHUTDOWN_EXECUTIVE - Shutdown RTEMS, Top
@end ifinfo
@chapter Task Manager
@ifinfo
@menu
* Task Manager Introduction::
* Task Manager Background::
* Task Manager Operations::
* Task Manager Directives::
@end menu
@end ifinfo
@ifinfo
@node Task Manager Introduction, Task Manager Background, Task Manager, Task Manager
@end ifinfo
@section Introduction
The task manager provides a comprehensive set of directives to
@@ -46,31 +30,8 @@ by the task manager are:
@item @code{@value{DIRPREFIX}task_wake_when} - Wake up when specified
@end itemize
@ifinfo
@node Task Manager Background, Task Definition, Task Manager Introduction, Task Manager
@end ifinfo
@section Background
@ifinfo
@menu
* Task Definition::
* Task Control Block::
* Task States::
* Task Priority::
* Task Mode::
* Accessing Task Arguments::
* Floating Point Considerations::
* Building a Task's Attribute Set::
* Building a Mode and Mask::
@end menu
@end ifinfo
@ifinfo
@node Task Definition, Task Control Block, Task Manager Background, Task Manager Background
@end ifinfo
@subsection Task Definition
Many definitions of a task have been proposed in computer literature.
@@ -99,9 +60,6 @@ execution which can compete on its own for system resources. A
task is manifested by the existence of a task control block
(TCB).
@ifinfo
@node Task Control Block, Task States, Task Definition, Task Manager Background
@end ifinfo
@subsection Task Control Block
The Task Control Block (TCB) is an RTEMS defined data structure
@@ -126,9 +84,6 @@ restored from the TCB. When a task is restarted, the initial
state of the task is restored from the starting context area in
the task's TCB.
@ifinfo
@node Task States, Task Priority, Task Control Block, Task Manager Background
@end ifinfo
@subsection Task States
A task may exist in one of the following five states:
@@ -151,9 +106,6 @@ to the CPU for periods of time determined by the RTEMS
scheduling algorithm. The scheduling of a task is based on its
current state and priority.
@ifinfo
@node Task Priority, Task Mode, Task States, Task Manager Background
@end ifinfo
@subsection Task Priority
A task's priority determines its importance in relation to the
@@ -175,9 +127,6 @@ task will be allowed to execute. In general, the higher the
logical priority of a task, the more likely it is to receive
processor execution time.
@ifinfo
@node Task Mode, Accessing Task Arguments, Task Priority, Task Manager Background
@end ifinfo
@subsection Task Mode
A task's mode is a combination of the following four components:
@@ -237,9 +186,6 @@ specifies that the task will execute at interrupt level n.
@item @code{@value{RPREFIX}INTERRUPT_LEVEL(n)} - execute at interrupt level n
@end itemize
@ifinfo
@node Accessing Task Arguments, Floating Point Considerations, Task Mode, Task Manager Background
@end ifinfo
@subsection Accessing Task Arguments
All RTEMS tasks are invoked with a single argument which is
@@ -267,9 +213,6 @@ procedure User_Task (
Application tasks requiring more information may view this
single argument as an index into an array of parameter blocks.
@ifinfo
@node Floating Point Considerations, Building a Task's Attribute Set, Accessing Task Arguments, Task Manager Background
@end ifinfo
@subsection Floating Point Considerations
Creating a task with the @code{@value{RPREFIX}FLOATING_POINT} flag results
@@ -321,9 +264,6 @@ attribute. The consequence of a @code{@value{RPREFIX}NO_FLOATING_POINT}
task attempting to access the floating point unit is CPU dependent but will
generally result in an exception condition.
@ifinfo
@node Building a Task's Attribute Set, Building a Mode and Mask, Floating Point Considerations, Task Manager Background
@end ifinfo
@subsection Building a Task's Attribute Set
In general, an attribute set is built by a bitwise OR of the
@@ -355,9 +295,6 @@ tasks. If the task were global and used the numeric
coprocessor, then the attribute_set parameter would be
@code{@value{RPREFIX}GLOBAL @value{OR} @value{RPREFIX}FLOATING_POINT}.
@ifinfo
@node Building a Mode and Mask, Task Manager Operations, Building a Task's Attribute Set, Task Manager Background
@end ifinfo
@subsection Building a Mode and Mask
In general, a mode and its corresponding mask is built by a
@@ -482,29 +419,8 @@ interrupt level, while the mask parameter should be set to
@value{RPREFIX}NO_PREEMPT_MASK} to indicate that the calling task's
interrupt level and preemption mode are being altered.
@ifinfo
@node Task Manager Operations, Creating Tasks, Building a Mode and Mask, Task Manager
@end ifinfo
@section Operations
@ifinfo
@menu
* Creating Tasks::
* Obtaining Task IDs::
* Starting and Restarting Tasks::
* Suspending and Resuming Tasks::
* Delaying the Currently Executing Task::
* Changing Task Priority::
* Changing Task Mode::
* Notepad Locations::
* Task Deletion::
@end menu
@end ifinfo
@ifinfo
@node Creating Tasks, Obtaining Task IDs, Task Manager Operations, Task Manager Operations
@end ifinfo
@subsection Creating Tasks
The @code{@value{DIRPREFIX}task_create}
@@ -516,9 +432,6 @@ initial mode, and assigning it a task ID. Newly created tasks
are initially placed in the dormant state. All RTEMS tasks
execute in the most privileged mode of the processor.
@ifinfo
@node Obtaining Task IDs, Starting and Restarting Tasks, Creating Tasks, Task Manager Operations
@end ifinfo
@subsection Obtaining Task IDs
When a task is created, RTEMS generates a unique task ID and
@@ -531,9 +444,6 @@ obtained later using the @code{@value{DIRPREFIX}task_ident}
directive. The task ID is
used by other directives to manipulate this task.
@ifinfo
@node Starting and Restarting Tasks, Suspending and Resuming Tasks, Obtaining Task IDs, Task Manager Operations
@end ifinfo
@subsection Starting and Restarting Tasks
The @code{@value{DIRPREFIX}task_start}
@@ -566,9 +476,6 @@ returned to RTEMS. A task cannot be restarted unless it has
previously been started (i.e. dormant tasks cannot be
restarted). All restarted tasks are placed in the ready state.
@ifinfo
@node Suspending and Resuming Tasks, Delaying the Currently Executing Task, Starting and Restarting Tasks, Task Manager Operations
@end ifinfo
@subsection Suspending and Resuming Tasks
The @code{@value{DIRPREFIX}task_suspend}
@@ -590,9 +497,6 @@ suspension and leaves the task in the blocked state.
Suspending a task which is already suspended or resuming a
task which is not suspended is considered an error.
@ifinfo
@node Delaying the Currently Executing Task, Changing Task Priority, Suspending and Resuming Tasks, Task Manager Operations
@end ifinfo
@subsection Delaying the Currently Executing Task
The @code{@value{DIRPREFIX}task_wake_after} directive creates a sleep timer
@@ -610,9 +514,6 @@ a task to go to sleep until a specified date and time. The
calling task is blocked until the specified date and time has
occurred, at which time the task is unblocked.
@ifinfo
@node Changing Task Priority, Changing Task Mode, Delaying the Currently Executing Task, Task Manager Operations
@end ifinfo
@subsection Changing Task Priority
The @code{@value{DIRPREFIX}task_set_priority}
@@ -629,9 +530,6 @@ The @code{@value{DIRPREFIX}task_restart}
directive resets the priority of a task to its
original value.
@ifinfo
@node Changing Task Mode, Notepad Locations, Changing Task Priority, Task Manager Operations
@end ifinfo
@subsection Changing Task Mode
The @code{@value{DIRPREFIX}task_mode}
@@ -644,9 +542,6 @@ The @code{@value{DIRPREFIX}task_restart}
directive resets the mode of a task to its
original value.
@ifinfo
@node Notepad Locations, Task Deletion, Changing Task Mode, Task Manager Operations
@end ifinfo
@subsection Notepad Locations
RTEMS provides sixteen notepad locations for each task. Each
@@ -662,9 +557,6 @@ to set a task's notepad entry to a specified note. The
directive allows the user to obtain the note
contained in any one of the sixteen notepads of a specified task.
@ifinfo
@node Task Deletion, Task Manager Directives, Notepad Locations, Task Manager Operations
@end ifinfo
@subsection Task Deletion
RTEMS provides the @code{@value{DIRPREFIX}task_delete}
@@ -692,30 +584,8 @@ task to delete itself by sending a "delete self" message, event,
or signal, or by restarting the task with special arguments
which instruct the task to delete itself.
@ifinfo
@node Task Manager Directives, TASK_CREATE - Create a task, Task Deletion, Task Manager
@end ifinfo
@section Directives
@ifinfo
@menu
* TASK_CREATE - Create a task::
* TASK_IDENT - Get ID of a task::
* TASK_START - Start a task::
* TASK_RESTART - Restart a task::
* TASK_DELETE - Delete a task::
* TASK_SUSPEND - Suspend a task::
* TASK_RESUME - Resume a task::
* TASK_SET_PRIORITY - Set task priority::
* TASK_MODE - Change current task's mode::
* TASK_GET_NOTE - Get task notepad entry::
* TASK_SET_NOTE - Set task notepad entry::
* TASK_WAKE_AFTER - Wake up after interval::
* TASK_WAKE_WHEN - Wake up when specified::
@end menu
@end ifinfo
This section details the task manager's directives. A
subsection is dedicated to each of this manager's directives and
describes the calling sequence, related constants, usage, and
@@ -723,9 +593,6 @@ status codes.
@page
@ifinfo
@node TASK_CREATE - Create a task, TASK_IDENT - Get ID of a task, Task Manager Directives, Task Manager Directives
@end ifinfo
@subsection TASK_CREATE - Create a task
@subheading CALLING SEQUENCE:
@@ -835,9 +702,6 @@ by the maximum_global_objects field in the Configuration Table.
@page
@ifinfo
@node TASK_IDENT - Get ID of a task, TASK_START - Start a task, TASK_CREATE - Create a task, Task Manager Directives
@end ifinfo
@subsection TASK_IDENT - Get ID of a task
@subheading CALLING SEQUENCE:
@@ -893,9 +757,6 @@ accesses only the local copy of the global object table.
@page
@ifinfo
@node TASK_START - Start a task, TASK_RESTART - Restart a task, TASK_IDENT - Get ID of a task, Task Manager Directives
@end ifinfo
@subsection TASK_START - Start a task
@subheading CALLING SEQUENCE:
@@ -945,9 +806,6 @@ the @code{@value{DIRPREFIX}task_start} directive.
@page
@ifinfo
@node TASK_RESTART - Restart a task, TASK_DELETE - Delete a task, TASK_START - Start a task, Task Manager Directives
@end ifinfo
@subsection TASK_RESTART - Restart a task
@subheading CALLING SEQUENCE:
@@ -1009,9 +867,6 @@ created with the @code{@value{RPREFIX}GLOBAL} option.
@page
@ifinfo
@node TASK_DELETE - Delete a task, TASK_SUSPEND - Suspend a task, TASK_RESTART - Restart a task, Task Manager Directives
@end ifinfo
@subsection TASK_DELETE - Delete a task
@subheading CALLING SEQUENCE:
@@ -1068,9 +923,6 @@ created with the @code{@value{RPREFIX}GLOBAL} option.
@page
@ifinfo
@node TASK_SUSPEND - Suspend a task, TASK_RESUME - Resume a task, TASK_DELETE - Delete a task, Task Manager Directives
@end ifinfo
@subsection TASK_SUSPEND - Suspend a task
@subheading CALLING SEQUENCE:
@@ -1119,9 +971,6 @@ If the task specified by id is already suspended, then the
@page
@ifinfo
@node TASK_RESUME - Resume a task, TASK_SET_PRIORITY - Set task priority, TASK_SUSPEND - Suspend a task, Task Manager Directives
@end ifinfo
@subsection TASK_RESUME - Resume a task
@subheading CALLING SEQUENCE:
@@ -1167,9 +1016,6 @@ If the task specified by id is not suspended, then the
@page
@ifinfo
@node TASK_SET_PRIORITY - Set task priority, TASK_MODE - Change current task's mode, TASK_RESUME - Resume a task, Task Manager Directives
@end ifinfo
@subsection TASK_SET_PRIORITY - Set task priority
@subheading CALLING SEQUENCE:
@@ -1231,9 +1077,6 @@ binary semaphores.
@page
@ifinfo
@node TASK_MODE - Change current task's mode, TASK_GET_NOTE - Get task notepad entry, TASK_SET_PRIORITY - Set task priority, Task Manager Directives
@end ifinfo
@subsection TASK_MODE - Change current task's mode
@subheading CALLING SEQUENCE:
@@ -1388,9 +1231,6 @@ mask constant is provided in the following table:
@page
@ifinfo
@node TASK_GET_NOTE - Get task notepad entry, TASK_SET_NOTE - Set task notepad entry, TASK_MODE - Change current task's mode, Task Manager Directives
@end ifinfo
@subsection TASK_GET_NOTE - Get task notepad entry
@subheading CALLING SEQUENCE:
@@ -1443,9 +1283,6 @@ the notepad entry of the specified task.
@page
@ifinfo
@node TASK_SET_NOTE - Set task notepad entry, TASK_WAKE_AFTER - Wake up after interval, TASK_GET_NOTE - Get task notepad entry, Task Manager Directives
@end ifinfo
@subsection TASK_SET_NOTE - Set task notepad entry
@subheading CALLING SEQUENCE:
@@ -1498,9 +1335,6 @@ node to set the specified notepad entry.
@page
@ifinfo
@node TASK_WAKE_AFTER - Wake up after interval, TASK_WAKE_WHEN - Wake up when specified, TASK_SET_NOTE - Set task notepad entry, Task Manager Directives
@end ifinfo
@subsection TASK_WAKE_AFTER - Wake up after interval
@subheading CALLING SEQUENCE:
@@ -1545,9 +1379,6 @@ A clock tick is required to support the functionality of this directive.
@page
@ifinfo
@node TASK_WAKE_WHEN - Wake up when specified, Interrupt Manager, TASK_WAKE_AFTER - Wake up after interval, Task Manager Directives
@end ifinfo
@subsection TASK_WAKE_WHEN - Wake up when specified
@subheading CALLING SEQUENCE: