Real-Time Interrupt-driven Concurrency (RTIC) framework for ARM Cortex-M microcontrollers
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bors[bot] bc024f1979 Merge #176
176:  implement RFCs 147 and 155, fix #141, etc. r=japaric a=japaric

This PR:

- Implements RFC 147: "all functions must be safe"

- Implements RFC 155: "explicit Context parameter"

- Implements the pending breaking change #141: reject assign syntax in `init`
  (which was used to initialize late resources)

- Refactors code generation to make it more readable -- there are no more random
  identifiers in the output -- and align it with the book description of RTFM
  internals (see PR #175).

- Makes the framework hard depend on `core::mem::MaybeUninit` and thus will
  require nightly until that API is stabilized.

- Fixes a ceiling analysis bug where the priority of the system timer was not
  considered in the analysis (TODO backport this into the v0.4.x branch).

- Shrinks the size of all the internal queues by turning `AtomicUsize` indices
  into `AtomicU8`s.

- Removes the integration with `owned_singleton`.

closes #141
closes #147
closes #155

Additionally:

- This changes CI to push v0.5.x docs to
  https://japaric.github.io/rtfm5/book/en/ -- we need to do this because our
  official docs are hosted on https://japaric.github.io/cortex-m-rtfm and we
  need to keep them on v0.4.x until we release v0.5.0

- I propose that we use the master branch to develop the upcoming v0.5.0.

- I have created a branch v0.4.x for backports; new v0.4.x releases will come
  from that branch.

r? @korken89 @texitoi, sorry for doing all the impl work in a single commit --
I know that makes things harder to review for you.

Suggestions for compile-pass and compile-fail tests are welcome


Co-authored-by: Jorge Aparicio <jorge@japaric.io>
2019-05-01 19:50:50 +00:00
.cargo v0.4.0 2018-11-03 17:16:55 +01:00
.github bors: do not merge PRs labeled S-blocked 2019-04-21 21:05:57 +02:00
book book: indirection for faster message passing 2019-05-01 21:32:00 +02:00
ci book: indirection for faster message passing 2019-05-01 21:32:00 +02:00
examples book: indirection for faster message passing 2019-05-01 21:32:00 +02:00
macros rtfm::app: update error message 2019-05-01 20:49:25 +02:00
src implement RFCs 147 and 155, etc. 2019-05-01 20:49:25 +02:00
tests test RFC 147 2019-05-01 20:49:25 +02:00
.gitignore Make identifiers deterministic. 2019-02-16 00:23:01 +01:00
.travis.yml travis: disable builds on stable 2019-05-01 20:49:25 +02:00
build.rs note that the timer queue is not supported on ARMv6-M 2018-12-16 19:38:22 +01:00
Cargo.toml book: indirection for faster message passing 2019-05-01 21:32:00 +02:00
CHANGELOG.md implement RFCs 147 and 155, etc. 2019-05-01 20:49:25 +02:00
LICENSE-APACHE initial commit 2017-03-05 00:29:08 -05:00
LICENSE-CC-BY-SA v0.4.0 2018-11-03 17:16:55 +01:00
LICENSE-MIT v0.4.0 2018-11-03 17:16:55 +01:00
README.md push docs to another repo & update README 2019-05-01 20:49:25 +02:00
redirect.html fancier redirect page 2019-02-14 21:57:43 +01:00

Real Time For the Masses

A concurrency framework for building real time systems.

Features

  • Tasks as the unit of concurrency 1. Tasks can be event triggered (fired in response to asynchronous stimuli) or spawned by the application on demand.

  • Message passing between tasks. Specifically, messages can be passed to software tasks at spawn time.

  • A timer queue 2. Software tasks can be scheduled to run at some time in the future. This feature can be used to implement periodic tasks.

  • Support for prioritization of tasks and, thus, preemptive multitasking.

  • Efficient and data race free memory sharing through fine grained priority based critical sections 1.

  • Deadlock free execution guaranteed at compile time. This is an stronger guarantee than what's provided by the standard Mutex abstraction.

  • Minimal scheduling overhead. The task scheduler has minimal software footprint; the hardware does the bulk of the scheduling.

  • Highly efficient memory usage: All the tasks share a single call stack and there's no hard dependency on a dynamic memory allocator.

  • All Cortex-M devices are supported. The core features of RTFM are supported on all Cortex-M devices. The timer queue is currently only supported on ARMv7-M devices.

  • This task model is amenable to known WCET (Worst Case Execution Time) analysis and scheduling analysis techniques. (Though we haven't yet developed Rust friendly tooling for that.)

Requirements

  • Rust 1.36.0+

  • Applications must be written using the 2018 edition.

User documentation

API reference

Acknowledgments

This crate is based on the RTFM language created by the Embedded Systems group at Luleå University of Technology, led by Prof. Per Lindgren.

References

License

All source code (including code snippets) is licensed under either of

at your option.

The written prose contained within the book is licensed under the terms of the Creative Commons CC-BY-SA v4.0 license (LICENSE-CC-BY-SA or https://creativecommons.org/licenses/by-sa/4.0/legalcode).

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be licensed as above, without any additional terms or conditions.


  1. Eriksson, J., Häggström, F., Aittamaa, S., Kruglyak, A., & Lindgren, P. (2013, June). Real-time for the masses, step 1: Programming API and static priority SRP kernel primitives. In Industrial Embedded Systems (SIES), 2013 8th IEEE International Symposium on (pp. 110-113). IEEE. ↩︎

  2. Lindgren, P., Fresk, E., Lindner, M., Lindner, A., Pereira, D., & Pinho, L. M. (2016). Abstract timers and their implementation onto the arm cortex-m family of mcus. ACM SIGBED Review, 13(1), 48-53. ↩︎