Only upgrade Arc twice

tokio/src/io/driver/mod.rs

@@ -315,7 +315,7 @@ impl Handle {
 
     pub(crate) fn is_shutdown(&self) -> bool {
         if let Some(inner) = self.inner.upgrade() {
-            inner.is_shutdown.load(Ordering::SeqCst)
+            inner.is_shutdown()
         } else {
             // if the inner type has been dropped then its `Drop` impl will have been called which
             // sets `Inner.is_shutdown` to `true`. So therefore it must have been shutdown.
@@ -366,6 +366,10 @@ impl Inner {
     pub(super) fn deregister_source(&self, source: &mut impl mio::event::Source) -> io::Result<()> {
         self.registry.deregister(source)
     }
+
+    pub(super) fn is_shutdown(&self) -> bool {
+        self.is_shutdown.load(Ordering::SeqCst)
+    }
 }
 
 impl Direction {

tokio/src/io/driver/registration.rs

@@ -239,7 +239,8 @@ cfg_io_readiness! {
             pin!(fut);
 
             crate::future::poll_fn(|cx| {
-                if self.handle.inner().is_none() || self.handle.is_shutdown() {
+                let inner = self.handle.inner();
+                if inner.is_none() || inner.filter(|i| i.is_shutdown()).is_some() {
                     return Poll::Ready(Err(io::Error::new(io::ErrorKind::Other, "reactor gone")));
                 }