Crate embassy_executor

embassy-executor

An async/await executor designed for embedded usage.

• No alloc, no heap needed. Task futures are statically allocated.
• No “fixed capacity” data structures, executor works with 1 or 1000 tasks without needing config/tuning.
• Integrated timer queue: sleeping is easy, just do Timer::after_secs(1).await;.
• No busy-loop polling: CPU sleeps when there’s no work to do, using interrupts or WFE/SEV.
• Efficient polling: a wake will only poll the woken task, not all of them.
• Fair: a task can’t monopolize CPU time even if it’s constantly being woken. All other tasks get a chance to run before a given task gets polled for the second time.
• Creating multiple executor instances is supported, to run tasks with multiple priority levels. This allows higher-priority tasks to preempt lower-priority tasks.

Modules

• raw
  Raw executor.

Structs

• Executor
  Thread mode executor, using WFE/SEV.
• InterruptExecutor
  Interrupt mode executor.
• SendSpawner
  Handle to spawn tasks into an executor from any thread.
• SpawnToken
  Token to spawn a newly-created task in an executor.
• Spawner
  Handle to spawn tasks into an executor.

Enums

• SpawnError
  Error returned when spawning a task.

Attribute Macros

• main
  Creates a new executor instance and declares an application entry point for Cortex-M spawning the corresponding function body as an async task.
• task
  Declares an async task that can be run by embassy-executor. The optional pool_size parameter can be used to specify how many concurrent tasks can be spawned (default is 1) for the function.