Self wakes are not detected

[hds]

What crate(s) in this repo are involved in the problem?

No response

What is the issue?

Self wakes are not being detected by tokio console.

How can the bug be reproduced?

The burn task in the app example should result in self wakes, because it calls tokio::task::yield_now() from within the task.

#[tracing::instrument]
async fn burn(min: u64, max: u64) {
    loop {
        for i in min..max {
            for _ in 0..i {
                tokio::task::yield_now().await;
            }
            tokio::time::sleep(Duration::from_secs(i - min)).await;
        }
    }
}

Looking at the logic of yield_now(), it seems that it may not actually result in a self wake (wake being called from within the span of the task being woken). So to check, I replaced the call to yield_now() with a call to a simple_yield_now() which should always wake within the span of the task:

async fn simple_yield_now() {
    pub struct YieldNow {
        yielded: bool,
    }

    impl Future for YieldNow {
        type Output = ();

        fn poll(
            mut self: std::pin::Pin<&mut Self>,
            cx: &mut std::task::Context<'_>,
        ) -> Poll<Self::Output> {
            if self.yielded == true {
                return Poll::Ready(());
            }

            self.yielded = true;
            cx.waker().wake_by_ref();

            Poll::Pending
        }
    }

    YieldNow { yielded: false }.await
}

However, tokio-console still fails to report a self wake.

Logs, error output, etc

We the following in the traces:

2023-05-15T14:07:54.387864Z TRACE runtime.spawn{kind=task task.name=burn task.id=19 loc.file="console-subscriber/examples/self-wake.rs" loc.line=11 loc.col=10}:burn{min=1 max=10}: tokio::task::waker: op="waker.wake_by_ref" task.id=1

Unfortunately, the task.id field in runtime.spawn span refers to the Tokio Task ID of the task, whereas the task.id in the waker event is the Span ID of the runtime.spawn span. So it's not immediately clear why

Versions

• tokio-console v0.1.8
• console-subscriber v0.1.9

It's also occuring on main at the time of writing cbf6f5.

Possible solution

No response

Additional context

No response

Would you like to work on fixing this bug?

yes