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doc: Minor edits needed on microkernel_fibers.rst

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General grammar edits: removed an "is is", added clarification, and
removed Latin abbreviation as per style guide reqs.

Change-Id: Ie9365dea2cdf27c107675487d4bf392711f4acb2
Signed-off-by: L.S. Cook <leonax.cook@intel.com>
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L.S. Cook 2016-02-24 07:10:33 -08:00 • committed by Gerrit Code Review
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doc/kernel/microkernel/microkernel_fibers.rst
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@ -6,16 +6,16 @@ Fiber Services
Concepts Concepts
******** ********
A fiber is a lightweight, non-preemptible thread of execution that implements A :dfn:`fiber` is a lightweight, non-preemptible thread of execution that
a portion of an application's processing. It is is normally used when writing implements a portion of an application's processing. Fiber-based services are
device drivers and other performance critical work. often used in device drivers and for performance-critical work.
A microkernel application can use all of the fiber capabilities that are A microkernel application can use all of the fiber capabilities that are
available to a nanokernel application; for more information see available to a nanokernel application; for more information see
:ref:`Nanokernel Fiber Services <nanokernel_fibers>`. :ref:`nanokernel_fibers`.
While a fiber often uses one or more nanokernel object types to carry While a fiber often uses one or more nanokernel object types to carry
out its work, it can also interact with microkernel events and semaphores out its work, it also can interact with microkernel events and semaphores
to a limited degree. For example, a fiber can signal a task by giving a to a limited degree. For example, a fiber can signal a task by giving a
microkernel semaphore, but it cannot take a microkernel semaphore. For more microkernel semaphore, but it cannot take a microkernel semaphore. For more
information see :ref:`microkernel_events` and :ref:`microkernel_semaphores`. information see :ref:`microkernel_events` and :ref:`microkernel_semaphores`.
@ -28,12 +28,20 @@ Microkernel Server Fiber
The microkernel automatically spawns a system thread, known as the The microkernel automatically spawns a system thread, known as the
*microkernel server* fiber, which performs most operations involving *microkernel server* fiber, which performs most operations involving
microkernel objects; see :ref:`Microkernel Server <microkernel_server>`. microkernel objects. The nanokernel scheduler decides which fibers
get scheduled and when; it will schedule the microkernel server fiber
when there are no fibers of a higher priority.
Both the fiber's stack size and scheduling priority can be configured, By default, the microkernel server fiber has priority 0 (that is,
using the :option:`MICROKERNEL_SERVER_STACK_SIZE` and the highest priority). However, this can be changed. If you drop its
:option:`MICROKERNEL_SERVER_PRIORITY` configuration options, respectively. priority, the nanokernel scheduler will give precedence to other,
higher-priority fibers, such as time-sensitive device driver or
application fibers.
By default, the microkernel server has priority 0 (i.e. highest priority). Both the fiber's stack size and scheduling priority can be configured
However, this can be changed so that the nanokernel scheduler gives precedence with the :option:`MICROKERNEL_SERVER_STACK_SIZE` and
to other fibers, such as time-sensitive device driver or application fibers. :option:`MICROKERNEL_SERVER_PRIORITY` configuration options,
respectively.
See also :ref:`microkernel_server`.