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#![allow(unknown_lints, unexpected_cfgs)]
#![cfg(all(
tokio_unstable,
tokio_taskdump,
target_os = "linux",
any(target_arch = "aarch64", target_arch = "x86", target_arch = "x86_64")
))]
use std::future::Future;
use std::pin::Pin;
use std::sync::{Arc, Mutex};
use std::task::{Context, Poll};
use std::time::{Duration, Instant};
use tokio::runtime::dump::{Root, Trace};
pin_project_lite::pin_project! {
pub struct PrettyFuture<F: Future> {
#[pin]
f: Root<F>,
t_last: State,
logs: Arc<Mutex<Vec<Trace>>>,
}
}
enum State {
NotStarted,
Running { since: Instant },
Alerted,
}
impl<F: Future> PrettyFuture<F> {
pub fn pretty(f: F, logs: Arc<Mutex<Vec<Trace>>>) -> Self {
PrettyFuture {
f: Trace::root(f),
t_last: State::NotStarted,
logs,
}
}
}
impl<F: Future> Future for PrettyFuture<F> {
type Output = F::Output;
fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<F::Output> {
let mut this = self.project();
let now = Instant::now();
let t_last = match this.t_last {
State::Running { since } => Some(*since),
State::NotStarted => {
*this.t_last = State::Running { since: now };
None
}
State::Alerted => {
// don't double-alert for the same future
None
}
};
if t_last.is_some_and(|t_last| now.duration_since(t_last) > Duration::from_millis(500)) {
let (res, trace) = tokio::runtime::dump::Trace::capture(|| this.f.as_mut().poll(cx));
this.logs.lock().unwrap().push(trace);
*this.t_last = State::Alerted;
return res;
}
this.f.poll(cx)
}
}
#[tokio::test]
async fn task_trace_self() {
let log = Arc::new(Mutex::new(vec![]));
let log2 = Arc::new(Mutex::new(vec![]));
let mut good_line = vec![];
let mut bad_line = vec![];
PrettyFuture::pretty(
PrettyFuture::pretty(
async {
bad_line.push(line!() + 1);
tokio::task::yield_now().await;
bad_line.push(line!() + 1);
tokio::time::sleep(Duration::from_millis(1)).await;
for _ in 0..100 {
good_line.push(line!() + 1);
tokio::time::sleep(Duration::from_millis(10)).await;
}
},
log.clone(),
),
log2.clone(),
)
.await;
for line in good_line {
let s = format!("{}:{}:", file!(), line);
assert!(log.lock().unwrap().iter().any(|x| {
eprintln!("{}", x);
format!("{}", x).contains(&s)
}));
}
for line in bad_line {
let s = format!("{}:{}:", file!(), line);
assert!(!log
.lock()
.unwrap()
.iter()
.any(|x| format!("{}", x).contains(&s)));
}
}