Crate ax_task 

ArceOS task management module.

This module provides primitives for task management, including task creation, scheduling, sleeping, termination, etc. The scheduler algorithm is configurable by cargo features.

Cargo Features

Multi-task scheduling and interrupt handling are mandatory runtime capabilities. Timer-based APIs such as sleep, sleep_until, and WaitQueue::wait_timeout are always available.

• preempt: Enable preemptive scheduling.
• FIFO cooperative scheduler is the default when no scheduler feature is selected.
• sched-rr: Use the Round-robin preemptive scheduler. It also enables the preempt feature.
• sched-cfs: Use the Completely Fair Scheduler. It also enables the preempt feature.
• host-test: Use host-safe fallbacks for unit tests.

Modules

future

Future support.

sync

Native ArceOS synchronization primitives. Native ArceOS synchronization implementation.

Structs

CurrentTask

A wrapper of AxTaskRef as the current task.

HardKernelTimerCallback

Explicit capability for a bounded callback that may execute in hard IRQ.

InterruptSnapshot

A task interruption observation captured before an owner-side safe-point scan.

IrqNotify

IRQ-safe deferred notification primitive.

KernelTimerHandle

Stable identity of one host kernel-timer registration.

MonotonicDeadline

Finite absolute deadline in the host monotonic clock domain.

MonotonicInstant

Sample from the same monotonic clock domain as MonotonicDeadline.

TaskId

A unique identifier for a thread.

TaskInner

The inner task structure.

TimerCpuId

Dense logical CPU identity owning one kernel timer registration.

WaitQueue

A queue to store sleeping tasks.

Enums

HardKernelTimerAction

Result returned by an explicitly hard-expiry callback.

KernelTimerAction

Result returned by a restartable kernel-timer callback.

KernelTimerCancelOutcome

Outcome of a non-blocking kernel-timer cancellation attempt.

KernelTimerError

Errors from the shared host kernel-timer service.

TaskState

The possible states of a task.

Traits

ClockEventControl

Publishes an earlier local deadline to the physical clockevent owner.

Functions

arm_hard_kernel_timer

Rearms an inactive hard timer on its registration CPU.

cancel_kernel_timer

Cancels a kernel-timer registration without waiting for an executing callback.

cpu_busy_ticks

Scheduler ticks CPU cpu has spent running a non-idle task since boot.

current

Gets the current task.

current_may_uninit

Gets the current task, or returns None if the current task is not initialized.

default_task_stack_size

Returns the default stack size used by task creation helpers.

disarm_hard_kernel_timer

Disarms a stable hard timer without destroying its callback payload.

exit

Exits the current task.

in_atomic_context

Returns whether the current context is atomic, meaning sleeping or rescheduling is not allowed.

init_scheduler

Initializes the task scheduler (for the primary CPU).

init_scheduler_secondary

Initializes the task scheduler for secondary CPUs.

init_timer_service

Starts the owner CPU’s shared soft-timer service.

might_sleep

Marks an operation as one that may sleep or reschedule.

on_timer_irq

Handles a hardware timer interrupt.

on_timer_tick

Handles periodic timer ticks for the task manager.

register_hard_restartable_kernel_timer

Registers a stable callback with explicit hard-IRQ expiry semantics.

register_kernel_timer

Registers a one-shot callback on the calling CPU’s shared timer base.

register_restartable_kernel_timer

Registers a task-context callback that can rearm the same timer identity.

register_task

Registers a task for lookup by its scheduler task id.

register_timer_callback

Registers a callback function to be called on each timer tick.

run_idle

The idle task routine.

set_current_affinity

Set the affinity for the current task. AxCpuMask is used to specify the CPU affinity. Returns true if the affinity is set successfully.

set_priority

Set the priority for current task.

sleep

Current task is going to sleep for the given duration.

sleep_until

Current task is going to sleep, it will be woken up at the given deadline. The deadline is measured against the monotonic clock.

spawn

Spawns a new task with the default parameters.

spawn_raw

Spawns a new task with the given parameters.

spawn_task

Adds the given task to the run queue, returns the task reference.

spawn_task_with

Initializes the given task before adding it to the run queue.

spawn_with_name

Spawns a new task with the given name and the default stack size.

task_by_id

Finds a task by its scheduler task id.

wake_task

Wakes a task that may be sleeping, ensuring it can observe a newly- delivered signal.

wake_task_by_id

Wakes a task by its scheduler task id.

yield_now

Current task gives up the CPU time voluntarily, and switches to another ready task.

Type Aliases

AxCpuMask

The wrapper type for ax_cpumask::CpuMask with SMP configuration.

AxTaskRef

The reference type of a task.

KernelTimerCallback

Callback executed by the owner CPU’s ktimers/%u service thread.

RestartableKernelTimerCallback

Callback for a stable timer registration that may restart itself.

WeakAxTaskRef

The weak reference type of a task.