diff options
Diffstat (limited to 'src/sync/rwlock/read_guard.rs')
| -rw-r--r-- | src/sync/rwlock/read_guard.rs | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/src/sync/rwlock/read_guard.rs b/src/sync/rwlock/read_guard.rs index 090b297..f5fc1d6 100644 --- a/src/sync/rwlock/read_guard.rs +++ b/src/sync/rwlock/read_guard.rs @@ -12,7 +12,10 @@ use std::ops; /// /// [`read`]: method@crate::sync::RwLock::read /// [`RwLock`]: struct@crate::sync::RwLock +#[must_use = "if unused the RwLock will immediately unlock"] pub struct RwLockReadGuard<'a, T: ?Sized> { + #[cfg(all(tokio_unstable, feature = "tracing"))] + pub(super) resource_span: tracing::Span, pub(super) s: &'a Semaphore, pub(super) data: *const T, pub(super) marker: marker::PhantomData<&'a T>, @@ -59,12 +62,17 @@ impl<'a, T: ?Sized> RwLockReadGuard<'a, T> { { let data = f(&*this) as *const U; let s = this.s; + #[cfg(all(tokio_unstable, feature = "tracing"))] + let resource_span = this.resource_span.clone(); // NB: Forget to avoid drop impl from being called. mem::forget(this); + RwLockReadGuard { s, data, marker: marker::PhantomData, + #[cfg(all(tokio_unstable, feature = "tracing"))] + resource_span, } } @@ -113,12 +121,17 @@ impl<'a, T: ?Sized> RwLockReadGuard<'a, T> { None => return Err(this), }; let s = this.s; + #[cfg(all(tokio_unstable, feature = "tracing"))] + let resource_span = this.resource_span.clone(); // NB: Forget to avoid drop impl from being called. mem::forget(this); + Ok(RwLockReadGuard { s, data, marker: marker::PhantomData, + #[cfg(all(tokio_unstable, feature = "tracing"))] + resource_span, }) } } @@ -152,5 +165,14 @@ where impl<'a, T: ?Sized> Drop for RwLockReadGuard<'a, T> { fn drop(&mut self) { self.s.release(1); + + #[cfg(all(tokio_unstable, feature = "tracing"))] + self.resource_span.in_scope(|| { + tracing::trace!( + target: "runtime::resource::state_update", + current_readers = 1, + current_readers.op = "sub", + ) + }); } } |