executor: allow trace and rtos-trace to coexist additively.

Before, enabling `trace` would enable embassy-native tracing, and
enabling *both* would *disable* embassy-native tracing.

embassy-executor/Cargo.toml

@@ -115,7 +115,24 @@ arch-spin = ["_arch"]
 executor-thread = []
 ## Enable the interrupt-mode executor (available in Cortex-M only)
 executor-interrupt = []
-## Enable tracing support (adds some overhead)
-trace = []
+## Enable tracing hooks
+trace = ["_any_trace"]
 ## Enable support for rtos-trace framework
-rtos-trace = ["dep:rtos-trace", "trace", "dep:embassy-time-driver"]
+rtos-trace = ["dep:rtos-trace", "_any_trace", "dep:embassy-time-driver"]
+_any_trace = []
+
+#! ### Timer Item Payload Size
+#! Sets the size of the payload for timer items, allowing integrated timer implementors to store
+#! additional data in the timer item. The payload field will be aligned to this value as well.
+#! If these features are not defined, the timer item will contain no payload field.
+
+_timer-item-payload = [] # A size was picked
+
+## 1 bytes
+timer-item-payload-size-1 = ["_timer-item-payload"]
+## 2 bytes
+timer-item-payload-size-2 = ["_timer-item-payload"]
+## 4 bytes
+timer-item-payload-size-4 = ["_timer-item-payload"]
+## 8 bytes
+timer-item-payload-size-8 = ["_timer-item-payload"]

embassy-executor/src/raw/mod.rs

@@ -16,7 +16,7 @@ mod run_queue;
 #[cfg_attr(not(target_has_atomic = "8"), path = "state_critical_section.rs")]
 mod state;
 
-#[cfg(feature = "trace")]
+#[cfg(feature = "_any_trace")]
 pub mod trace;
 pub(crate) mod util;
 #[cfg_attr(feature = "turbowakers", path = "waker_turbo.rs")]
@@ -94,9 +94,9 @@ pub(crate) struct TaskHeader {
 
     /// Integrated timer queue storage. This field should not be accessed outside of the timer queue.
     pub(crate) timer_queue_item: TimerQueueItem,
-    #[cfg(feature = "trace")]
+    #[cfg(feature = "_any_trace")]
     pub(crate) name: Option<&'static str>,
-    #[cfg(feature = "trace")]
+    #[cfg(feature = "rtos-trace")]
     all_tasks_next: AtomicPtr<TaskHeader>,
 }
 
@@ -193,9 +193,9 @@ impl<F: Future + 'static> TaskStorage<F> {
                 poll_fn: SyncUnsafeCell::new(None),
 
                 timer_queue_item: TimerQueueItem::new(),
-                #[cfg(feature = "trace")]
+                #[cfg(feature = "_any_trace")]
                 name: None,
-                #[cfg(feature = "trace")]
+                #[cfg(feature = "rtos-trace")]
                 all_tasks_next: AtomicPtr::new(core::ptr::null_mut()),
             },
             future: UninitCell::uninit(),
@@ -231,7 +231,7 @@ impl<F: Future + 'static> TaskStorage<F> {
         let mut cx = Context::from_waker(&waker);
         match future.poll(&mut cx) {
             Poll::Ready(_) => {
-                #[cfg(feature = "trace")]
+                #[cfg(feature = "_any_trace")]
                 let exec_ptr: *const SyncExecutor = this.raw.executor.load(Ordering::Relaxed);
 
                 // As the future has finished and this function will not be called
@@ -246,7 +246,7 @@ impl<F: Future + 'static> TaskStorage<F> {
                 // after we're done with it.
                 this.raw.state.despawn();
 
-                #[cfg(feature = "trace")]
+                #[cfg(feature = "_any_trace")]
                 trace::task_end(exec_ptr, &p);
             }
             Poll::Pending => {}
@@ -419,7 +419,7 @@ impl SyncExecutor {
     /// - `task` must NOT be already enqueued (in this executor or another one).
     #[inline(always)]
     unsafe fn enqueue(&self, task: TaskRef, l: state::Token) {
-        #[cfg(feature = "trace")]
+        #[cfg(feature = "_any_trace")]
         trace::task_ready_begin(self, &task);
 
         if self.run_queue.enqueue(task, l) {
@@ -432,7 +432,7 @@ impl SyncExecutor {
             .executor
             .store((self as *const Self).cast_mut(), Ordering::Relaxed);
 
-        #[cfg(feature = "trace")]
+        #[cfg(feature = "_any_trace")]
         trace::task_new(self, &task);
 
         state::locked(|l| {
@@ -444,23 +444,23 @@ impl SyncExecutor {
     ///
     /// Same as [`Executor::poll`], plus you must only call this on the thread this executor was created.
     pub(crate) unsafe fn poll(&'static self) {
-        #[cfg(feature = "trace")]
+        #[cfg(feature = "_any_trace")]
         trace::poll_start(self);
 
         self.run_queue.dequeue_all(|p| {
             let task = p.header();
 
-            #[cfg(feature = "trace")]
+            #[cfg(feature = "_any_trace")]
             trace::task_exec_begin(self, &p);
 
             // Run the task
             task.poll_fn.get().unwrap_unchecked()(p);
 
-            #[cfg(feature = "trace")]
+            #[cfg(feature = "_any_trace")]
             trace::task_exec_end(self, &p);
         });
 
-        #[cfg(feature = "trace")]
+        #[cfg(feature = "_any_trace")]
         trace::executor_idle(self)
     }
 }

embassy-executor/src/raw/trace.rs

@@ -95,17 +95,20 @@ use crate::spawner::{SpawnError, SpawnToken, Spawner};
 /// This static provides access to the global task tracker which maintains
 /// a list of all tasks in the system. It's automatically updated by the
 /// task lifecycle hooks in the trace module.
-pub static TASK_TRACKER: TaskTracker = TaskTracker::new();
+#[cfg(feature = "rtos-trace")]
+pub(crate) static TASK_TRACKER: TaskTracker = TaskTracker::new();
 
 /// A thread-safe tracker for all tasks in the system
 ///
 /// This struct uses an intrusive linked list approach to track all tasks
 /// without additional memory allocations. It maintains a global list of
 /// tasks that can be traversed to find all currently existing tasks.
-pub struct TaskTracker {
+#[cfg(feature = "rtos-trace")]
+pub(crate) struct TaskTracker {
     head: AtomicPtr<TaskHeader>,
 }
 
+#[cfg(feature = "rtos-trace")]
 impl TaskTracker {
     /// Creates a new empty task tracker
     ///
@@ -191,7 +194,7 @@ impl TaskRefTrace for TaskRef {
     }
 }
 
-#[cfg(not(feature = "rtos-trace"))]
+#[cfg(feature = "trace")]
 extern "Rust" {
     /// This callback is called when the executor begins polling. This will always
     /// be paired with a later call to `_embassy_trace_executor_idle`.
@@ -253,7 +256,7 @@ extern "Rust" {
 
 #[inline]
 pub(crate) fn poll_start(executor: &SyncExecutor) {
-    #[cfg(not(feature = "rtos-trace"))]
+    #[cfg(feature = "trace")]
     unsafe {
         _embassy_trace_poll_start(executor as *const _ as u32)
     }
@@ -261,7 +264,7 @@ pub(crate) fn poll_start(executor: &SyncExecutor) {
 
 #[inline]
 pub(crate) fn task_new(executor: &SyncExecutor, task: &TaskRef) {
-    #[cfg(not(feature = "rtos-trace"))]
+    #[cfg(feature = "trace")]
     unsafe {
         _embassy_trace_task_new(executor as *const _ as u32, task.as_ptr() as u32)
     }
@@ -285,7 +288,7 @@ pub(crate) fn task_new(executor: &SyncExecutor, task: &TaskRef) {
 
 #[inline]
 pub(crate) fn task_end(executor: *const SyncExecutor, task: &TaskRef) {
-    #[cfg(not(feature = "rtos-trace"))]
+    #[cfg(feature = "trace")]
     unsafe {
         _embassy_trace_task_end(executor as u32, task.as_ptr() as u32)
     }
@@ -293,7 +296,7 @@ pub(crate) fn task_end(executor: *const SyncExecutor, task: &TaskRef) {
 
 #[inline]
 pub(crate) fn task_ready_begin(executor: &SyncExecutor, task: &TaskRef) {
-    #[cfg(not(feature = "rtos-trace"))]
+    #[cfg(feature = "trace")]
     unsafe {
         _embassy_trace_task_ready_begin(executor as *const _ as u32, task.as_ptr() as u32)
     }
@@ -303,7 +306,7 @@ pub(crate) fn task_ready_begin(executor: &SyncExecutor, task: &TaskRef) {
 
 #[inline]
 pub(crate) fn task_exec_begin(executor: &SyncExecutor, task: &TaskRef) {
-    #[cfg(not(feature = "rtos-trace"))]
+    #[cfg(feature = "trace")]
     unsafe {
         _embassy_trace_task_exec_begin(executor as *const _ as u32, task.as_ptr() as u32)
     }
@@ -313,7 +316,7 @@ pub(crate) fn task_exec_begin(executor: &SyncExecutor, task: &TaskRef) {
 
 #[inline]
 pub(crate) fn task_exec_end(executor: &SyncExecutor, task: &TaskRef) {
-    #[cfg(not(feature = "rtos-trace"))]
+    #[cfg(feature = "trace")]
     unsafe {
         _embassy_trace_task_exec_end(executor as *const _ as u32, task.as_ptr() as u32)
     }
@@ -323,7 +326,7 @@ pub(crate) fn task_exec_end(executor: &SyncExecutor, task: &TaskRef) {
 
 #[inline]
 pub(crate) fn executor_idle(executor: &SyncExecutor) {
-    #[cfg(not(feature = "rtos-trace"))]
+    #[cfg(feature = "trace")]
     unsafe {
         _embassy_trace_executor_idle(executor as *const _ as u32)
     }
@@ -339,6 +342,7 @@ pub(crate) fn executor_idle(executor: &SyncExecutor) {
 ///
 /// # Returns
 /// An iterator that yields `TaskRef` items for each task
+#[cfg(feature = "rtos-trace")]
 fn get_all_active_tasks() -> impl Iterator<Item = TaskRef> + 'static {
     struct TaskIterator<'a> {
         tracker: &'a TaskTracker,
@@ -367,6 +371,7 @@ fn get_all_active_tasks() -> impl Iterator<Item = TaskRef> + 'static {
 }
 
 /// Perform an action on each active task
+#[cfg(feature = "rtos-trace")]
 fn with_all_active_tasks<F>(f: F)
 where
     F: FnMut(TaskRef),