Merge #897

897: Add support for `rtos-trace` behind a feature flag r=lulf a=quentinmit

This allows SystemView to be used to profile the behavior of the user's application.

Co-authored-by: Quentin Smith <[email protected]>

3 files changed, 64 insertions, 0 deletions

diff --git a/embassy-executor/Cargo.toml b/embassy-executor/Cargo.toml
index 25c3f0abd..7d5c4a045 100644
--- a/embassy-executor/Cargo.toml
+++ b/embassy-executor/Cargo.toml
@@ -30,9 +30,13 @@ nightly = []
 
 integrated-timers = ["dep:embassy-time"]
 
+# Trace interrupt invocations with rtos-trace.
+rtos-trace-interrupt = ["rtos-trace"]
+
 [dependencies]
 defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
+rtos-trace = { version = "0.1.2", optional = true }
 
 futures-util = { version = "0.3.17", default-features = false }
 embassy-macros  = { version = "0.1.0", path = "../embassy-macros"}
diff --git a/embassy-executor/src/lib.rs b/embassy-executor/src/lib.rs
index 9328a7378..93f2eaa6d 100644
--- a/embassy-executor/src/lib.rs
+++ b/embassy-executor/src/lib.rs
@@ -38,6 +38,31 @@ cfg_if::cfg_if! {
     }
 }
 
+#[doc(hidden)]
+/// Implementation details for embassy macros. DO NOT USE.
+pub mod export {
+    #[cfg(feature = "rtos-trace")]
+    pub use rtos_trace::trace;
+
+    /// Expands the given block of code when `embassy-executor` is compiled with
+    /// the `rtos-trace-interrupt` feature.
+    #[doc(hidden)]
+    #[macro_export]
+    #[cfg(feature = "rtos-trace-interrupt")]
+    macro_rules! rtos_trace_interrupt {
+        ($($tt:tt)*) => { $($tt)* };
+    }
+
+    /// Does not expand the given block of code when `embassy-executor` is
+    /// compiled without the `rtos-trace-interrupt` feature.
+    #[doc(hidden)]
+    #[macro_export]
+    #[cfg(not(feature = "rtos-trace-interrupt"))]
+    macro_rules! rtos_trace_interrupt {
+        ($($tt:tt)*) => {};
+    }
+}
+
 pub mod raw;
 
 mod spawner;
diff --git a/embassy-executor/src/raw/mod.rs b/embassy-executor/src/raw/mod.rs
index afe67decb..c55d10699 100644
--- a/embassy-executor/src/raw/mod.rs
+++ b/embassy-executor/src/raw/mod.rs
@@ -26,6 +26,8 @@ use critical_section::CriticalSection;
 use embassy_time::driver::{self, AlarmHandle};
 #[cfg(feature = "integrated-timers")]
 use embassy_time::Instant;
+#[cfg(feature = "rtos-trace")]
+use rtos_trace::trace;
 
 use self::run_queue::{RunQueue, RunQueueItem};
 use self::util::UninitCell;
@@ -306,6 +308,9 @@ impl Executor {
     /// - `task` must NOT be already enqueued (in this executor or another one).
     #[inline(always)]
     unsafe fn enqueue(&self, cs: CriticalSection, task: NonNull<TaskHeader>) {
+        #[cfg(feature = "rtos-trace")]
+        trace::task_ready_begin(task.as_ptr() as u32);
+
         if self.run_queue.enqueue(cs, task) {
             (self.signal_fn)(self.signal_ctx)
         }
@@ -323,6 +328,9 @@ impl Executor {
     pub(super) unsafe fn spawn(&'static self, task: NonNull<TaskHeader>) {
         task.as_ref().executor.set(self);
 
+        #[cfg(feature = "rtos-trace")]
+        trace::task_new(task.as_ptr() as u32);
+
         critical_section::with(|cs| {
             self.enqueue(cs, task);
         })
@@ -365,9 +373,15 @@ impl Executor {
                 return;
             }
 
+            #[cfg(feature = "rtos-trace")]
+            trace::task_exec_begin(p.as_ptr() as u32);
+
             // Run the task
             task.poll_fn.read()(p as _);
 
+            #[cfg(feature = "rtos-trace")]
+            trace::task_exec_end();
+
             // Enqueue or update into timer_queue
             #[cfg(feature = "integrated-timers")]
             self.timer_queue.update(p);
@@ -381,6 +395,9 @@ impl Executor {
             let next_expiration = self.timer_queue.next_expiration();
             driver::set_alarm(self.alarm, next_expiration.as_ticks());
         }
+
+        #[cfg(feature = "rtos-trace")]
+        trace::system_idle();
     }
 
     /// Get a spawner that spawns tasks in this executor.
@@ -426,3 +443,21 @@ unsafe fn _embassy_time_schedule_wake(at: Instant, waker: &core::task::Waker) {
     let expires_at = task.expires_at.get();
     task.expires_at.set(expires_at.min(at));
 }
+
+#[cfg(feature = "rtos-trace")]
+impl rtos_trace::RtosTraceOSCallbacks for Executor {
+    fn task_list() {
+        // We don't know what tasks exist, so we can't send them.
+    }
+    #[cfg(feature = "integrated-timers")]
+    fn time() -> u64 {
+        Instant::now().as_micros()
+    }
+    #[cfg(not(feature = "integrated-timers"))]
+    fn time() -> u64 {
+        0
+    }
+}
+
+#[cfg(feature = "rtos-trace")]
+rtos_trace::global_os_callbacks! {Executor}