Add heap usage stats with defmt

esp-alloc/CHANGELOG.md

@@ -9,6 +9,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- `esp_alloc::HEAP.stats()` can now be used to get heap usage informations (#2137)
+
 ### Changed
 
 ### Fixed

esp-alloc/Cargo.toml

@@ -23,10 +23,24 @@ default-target = "riscv32imc-unknown-none-elf"
 features       = ["nightly"]
 
 [dependencies]
+defmt                 = { version = "0.3.8", optional = true }
+cfg-if                = "1.0.0"
 critical-section      = "1.1.3"
 enumset               = "1.1.5"
 linked_list_allocator = { version = "0.10.5", default-features = false, features = ["const_mut_refs"] }
+document-features     = "0.2.10"
 
 [features]
 default = []
 nightly = []
+
+## Implement `defmt::Format` on certain types.
+defmt = ["dep:defmt"]
+
+## Enable this feature if you want to keep stats about the internal heap usage such as:
+## - Max memory usage since initialization of the heap
+## - Total allocated memory since initialization of the heap
+## - Total freed memory since initialization of the heap
+##
+## ⚠️ Note: Enabling this feature will require extra computation every time alloc/dealloc is called.
+internal-heap-stats = []