Crate ep_systick

EmbeddedProfiler implementation based on systick.

This profiler depends on the SYST hardware common to most cortex-M devices. The profiler’s configured resolution is the same as the core clock. The cycle count clock is free-running, so overflows are likely if you have long running functions to profile. To mitigate this, one can use the extended feature, which extends the resolution of the counter from 24 bit to u32 or u64 using the SysTick exception. It is set to expire just before overflow, so you can expect an exception to fire every 2**24 clock cycles.

Snapshots are logged using log::info!, so having a logger installed is required if you want to use embedded_profiling::log_snapshot or functions that call it (like embedded_profiling::profile_function).

Example Usage

 let mut core = CorePeripherals::take().unwrap();
 // (...)
 let dwt_profiler = cortex_m::singleton!(: ep_systick::SysTickProfiler::<CORE_FREQ> =
     ep_systick::SysTickProfiler::<CORE_FREQ>::new(core.SYST, CORE_FREQ))
 .unwrap();
 unsafe {
     embedded_profiling::set_profiler(dwt_profiler).unwrap();
 }
 // (...)
 embedded_profiling::profile("print_profile", || println!("Hello, world"));

Features

extended

as discussed above, extend the native resolution of 24 bits to either 32 or 64 bits using the SysTick exception. The exception fires ever 2**24 clock cycles.

container-u64

enables the container-u64 feature in embedded-profiling. Use a u64 as the time storage type instead of u32 for longer running profiling.

proc-macros

enables the proc-macros feature in embedded-profiling. Enables the embedded_profiling::profile_function procedural macro.

Structs

SysTickProfiler

systick implementation of EmbeddedProfiler.