zephyr/doc/api/kernel_api.rst

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.. _kernel_apis:
Kernel APIs
###########
This section contains APIs for the kernel's core services,
as described in the :ref:`kernel`.
.. important::
Unless otherwise noted these APIs can be used by threads, but not by ISRs.
.. contents::
:depth: 1
:local:
:backlinks: top
Threads
*******
A thread is an independently scheduled series of instructions that implements
a portion of an application's processing. Threads are used to perform processing
that is too lengthy or too complex to be performed by an ISR.
(See :ref:`threads_v2`.)
.. doxygengroup:: thread_apis
:project: Zephyr
:content-only:
Workqueues
**********
A workqueue processes a series of work items by executing the associated
functions in a dedicated thread. Workqueues are typically used by an ISR
or high-priority thread to offload non-urgent processing.
(See :ref:`workqueues_v2`.)
.. doxygengroup:: workqueue_apis
:project: Zephyr
:content-only:
Clocks
******
Kernel clocks enable threads and ISRs to measure the passage of time
with either normal and high precision.
(See :ref:`clocks_v2`.)
.. doxygengroup:: clock_apis
:project: Zephyr
:content-only:
Timers
******
Timers enable threads to measure the passage of time, and to optionally execute
an action when the timer expires.
(See :ref:`timers_v2`.)
.. doxygengroup:: timer_apis
:project: Zephyr
:content-only:
Memory Slabs
************
Memory slabs enable the dynamic allocation and release of fixed-size
memory blocks.
(See :ref:`memory_slabs_v2`.)
.. doxygengroup:: mem_slab_apis
:project: Zephyr
:content-only:
Memory Pools
************
Memory pools enable the dynamic allocation and release of variable-size
memory blocks.
(See :ref:`memory_pools_v2`.)
.. doxygengroup:: mem_pool_apis
:project: Zephyr
:content-only:
Heap Memory Pool
****************
The heap memory pools enable the dynamic allocation and release of memory
in a :cpp:func:`malloc()`-like manner.
(See :ref:`heap_v2`.)
.. doxygengroup:: heap_apis
:project: Zephyr
:content-only:
Semaphores
**********
Semaphores provide traditional counting semaphore capabilities.
(See :ref:`semaphores_v2`.)
.. doxygengroup:: semaphore_apis
:project: Zephyr
:content-only:
Mutexes
*******
Mutexes provide traditional reentrant mutex capabilities
with basic priority inheritance.
(See :ref:`mutexes_v2`.)
.. doxygengroup:: mutex_apis
:project: Zephyr
:content-only:
Alerts
******
Alerts enable an application to perform asynchronous signaling,
somewhat akin to Unix-style signals.
(See :ref:`alerts_v2`.)
.. doxygengroup:: alert_apis
:project: Zephyr
:content-only:
Fifos
*****
Fifos provide traditional first in, first out (FIFO) queuing of data items
of any size.
(See :ref:`fifos_v2`.)
.. doxygengroup:: fifo_apis
:project: Zephyr
:content-only:
Lifos
*****
Lifos provide traditional last in, first out (LIFO) queuing of data items
of any size.
(See :ref:`lifos_v2`.)
.. doxygengroup:: lifo_apis
:project: Zephyr
:content-only:
Stacks
******
Stacks provide traditional last in, first out (LIFO) queuing of 32-bit
data items.
(See :ref:`stacks_v2`.)
.. doxygengroup:: stack_apis
:project: Zephyr
:content-only:
Message Queues
**************
Message queues provide a simple message queuing mechanism
for fixed-size data items.
(See :ref:`message_queues_v2`.)
.. doxygengroup:: msgq_apis
:project: Zephyr
:content-only:
Mailboxes
*********
Mailboxes provide an enhanced message queuing mechanism
for variable-size messages.
(See :ref:`mailboxes_v2`.)
.. doxygengroup:: mailbox_apis
:project: Zephyr
:content-only:
Pipes
*****
Pipes provide a traditional anonymous pipe mechanism for sending
variable-size chunks of data, in whole or in part.
(See :ref:`pipes_v2`.)
.. doxygengroup:: pipe_apis
:project: Zephyr
:content-only:
Interrupt Service Routines (ISRs)
*********************************
An interrupt service routine is a series of instructions that is
executed asynchronously in response to a hardware or software interrupt.
(See :ref:`interrupts_v2`.)
.. doxygengroup:: isr_apis
:project: Zephyr
:content-only:
Atomic Services
***************
The atomic services enable multiple threads and ISRs to read and modify
32-bit variables in an uninterruptible manner.
(See :ref:`atomic_v2`.)
.. important::
All atomic services APIs can be used by both threads and ISRs.
.. doxygengroup:: atomic_apis
:project: Zephyr
:content-only:
Floating Point Services
***********************
The floating point services enable threads to use a board's floating point
registers.
(See :ref:`float_v2`.)
.. doxygengroup:: float_apis
:project: Zephyr
:content-only:
Ring Buffers
************
Ring buffers enable simple first in, first out (FIFO) queuing
of variable-size data items.
(See :ref:`ring_buffers_v2`.)
.. doxygengroup:: ring_buffer_apis
:project: Zephyr
:content-only: