Kernel metrics

[F42J]

No description provided.

[Copilot]

Pull request overview

This PR introduces a unified, optionally-enabled kernel metrics surface for observing heap allocator usage and per-thread stack usage, wired through the scheduler and HAL stack abstractions.

Changes:

• Add a new osiris::metrics module exposing global heap, per-task heap, and per-thread stack metrics APIs.
• Extend the best-fit allocator and Cortex-M stack implementation to track/report allocator and stack usage metrics (behind metrics feature / osiris_metrics cfg).
• Add build/config plumbing (OSIRIS_DEBUG_METRICS, feature flags, unexpected_cfgs allowlists) to enable metrics across crates.

Reviewed changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/sched/thread.rs	Adds per-thread stack metrics accessor (cfg-gated).
src/sched/task.rs	Adds per-task heap metrics accessor (cfg-gated).
src/sched.rs	Adds scheduler entry points to query per-thread/per-task metrics (cfg-gated).
src/metrics.rs	New unified public metrics API module.
src/mem/vmm/nommu.rs	Exposes AddressSpace allocator metrics (cfg-gated).
src/mem/alloc/bestfit.rs	Adds allocator metrics struct/counters, snapshot method, and tests (cfg-gated).
src/mem.rs	Adds global heap metrics snapshot helper (cfg-gated).
src/lib.rs	Exposes pub mod metrics behind cfg.
presets/stm32l4r5zi_def.toml	Adds OSIRIS_DEBUG_METRICS preset env var.
options.toml	Adds a debug.metrics option definition.
machine/cortex-m/src/native/sched.rs	Adds stack peak tracking + stack metrics implementation + tests (cfg-gated).
machine/cortex-m/Cargo.toml	Adds metrics feature and allows cfg(osiris_metrics) in lints.
machine/cortex-m/build.rs	Emits cfg(osiris_metrics) when OSIRIS_DEBUG_METRICS is set.
machine/api/src/stack.rs	Adds StackMetrics type + default Stacklike::metrics() (cfg-gated).
machine/api/Cargo.toml	Adds metrics feature and allows cfg(osiris_metrics) in lints.
machine/api/build.rs	Emits cfg(osiris_metrics) when OSIRIS_DEBUG_METRICS is set.
Cargo.toml	Adds top-level metrics feature and allows cfg(osiris_metrics) in lints.
build.rs	Emits cfg(osiris_metrics) when OSIRIS_DEBUG_METRICS is set.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[thomasw04]

Looks good. Left a few suggestions and comments. Also: please don't use mod.rs anymore, use the new layout like the rest of the codebase.