executor: rtos-trace: name main task

Assigns a name to the main task when (rtos-)tracing is active. This
improves tracing usability with the SystemView backend.

Signed-off-by: Florian Grandel <[email protected]>

2 files changed, 15 insertions, 2 deletions

diff --git a/embassy-executor-macros/src/macros/main.rs b/embassy-executor-macros/src/macros/main.rs
index fcc04d9c0..f043ff7f6 100644
--- a/embassy-executor-macros/src/macros/main.rs
+++ b/embassy-executor-macros/src/macros/main.rs
@@ -170,6 +170,14 @@ For example: `#[embassy_executor::main(entry = ..., executor = \"some_crate::Exe
     let f_body = f.body;
     let out = &f.sig.output;
 
+    let name_main_task = if cfg!(feature = "rtos-trace") {
+        quote!(
+            main_task.metadata().set_name("main\0");
+        )
+    } else {
+        quote!()
+    };
+
     let (main_ret, mut main_body) = match arch.flavor {
         Flavor::Standard => (
             quote!(!),
@@ -181,7 +189,9 @@ For example: `#[embassy_executor::main(entry = ..., executor = \"some_crate::Exe
                 let mut executor = #executor::new();
                 let executor = unsafe { __make_static(&mut executor) };
                 executor.run(|spawner| {
-                    spawner.spawn(__embassy_main(spawner).unwrap());
+                    let main_task = __embassy_main(spawner).unwrap();
+                    #name_main_task
+                    spawner.spawn(main_task);
                 })
             },
         ),
@@ -191,7 +201,9 @@ For example: `#[embassy_executor::main(entry = ..., executor = \"some_crate::Exe
                 let executor = ::std::boxed::Box::leak(::std::boxed::Box::new(#executor::new()));
 
                 executor.start(|spawner| {
-                    spawner.spawn(__embassy_main(spawner).unwrap());
+                    let main_task = __embassy_main(spawner).unwrap();
+                    #name_main_task
+                    spawner.spawn(main_task);
                 });
 
                 Ok(())
diff --git a/embassy-executor/CHANGELOG.md b/embassy-executor/CHANGELOG.md
index f2db46ef9..999c77a83 100644
--- a/embassy-executor/CHANGELOG.md
+++ b/embassy-executor/CHANGELOG.md
@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## Unreleased - ReleaseDate
 
 - Added new metadata API for tasks
+- Named main task when rtos-trace feature is enabled.
 
 ## 0.9.0 - 2025-08-26