Ignore io+shutdown tests for now due to known bugs

See
tokio-rs#3569 (review)
for more details

tokio/src/io/driver/mod.rs

@@ -14,7 +14,6 @@ pub(crate) use registration::Registration;
 mod scheduled_io;
 use scheduled_io::ScheduledIo;
 
-use crate::loom::sync::atomic::{AtomicBool, Ordering};
 use crate::park::{Park, Unpark};
 use crate::util::slab::{self, Slab};
 use crate::{loom::sync::Mutex, util::bit};
@@ -74,9 +73,6 @@ pub(super) struct Inner {
 
     /// Used to wake up the reactor from a call to `turn`
     waker: mio::Waker,
-
-    /// Whether the driver is shutdown.
-    is_shutdown: AtomicBool,
 }
 
 #[derive(Debug, Eq, PartialEq, Clone, Copy)]
@@ -133,7 +129,6 @@ impl Driver {
                 registry,
                 io_dispatch: allocator,
                 waker,
-                is_shutdown: AtomicBool::new(false),
             }),
         })
     }
@@ -213,8 +208,6 @@ impl Drop for Driver {
 
 impl Drop for Inner {
     fn drop(&mut self) {
-        self.is_shutdown.store(true, Ordering::SeqCst);
-
         let resources = self.resources.lock().take();
 
         if let Some(mut slab) = resources {
@@ -304,24 +297,6 @@ impl Handle {
     pub(super) fn inner(&self) -> Option<Arc<Inner>> {
         self.inner.upgrade()
     }
-
-    pub(crate) fn shutdown(self) {
-        if let Some(inner) = self.inner.upgrade() {
-            inner
-                .is_shutdown
-                .store(true, crate::loom::sync::atomic::Ordering::SeqCst);
-        }
-    }
-
-    pub(crate) fn is_shutdown(&self) -> bool {
-        if let Some(inner) = self.inner.upgrade() {
-            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.
-            true
-        }
-    }
 }
 
 impl Unpark for Handle {
@@ -366,10 +341,6 @@ 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

@@ -69,13 +69,6 @@ impl Registration {
         interest: Interest,
         handle: Handle,
     ) -> io::Result<Registration> {
-        if handle.is_shutdown() {
-            return Err(io::Error::new(
-                io::ErrorKind::Other,
-                crate::util::error::RUNTIME_SHUTTING_DOWN_ERROR,
-            ));
-        }
-
         let shared = if let Some(inner) = handle.inner() {
             inner.add_source(io, interest)?
         } else {
@@ -239,8 +232,7 @@ cfg_io_readiness! {
             pin!(fut);
 
             crate::future::poll_fn(|cx| {
-                let inner = self.handle.inner();
-                if inner.is_none() || inner.filter(|i| i.is_shutdown()).is_some() {
+                if self.handle.inner().is_none() {
                     return Poll::Ready(Err(io::Error::new(io::ErrorKind::Other, "reactor gone")));
                 }
 

tokio/src/runtime/handle.rs

@@ -216,20 +216,8 @@ impl Handle {
             .expect("failed to park thread")
     }
 
-    cfg_io_driver! {
-        pub(crate) fn shutdown(mut self) {
-            self.spawner.shutdown();
-
-            if let Some(io_handle) = self.io_handle {
-                io_handle.shutdown();
-            }
-        }
-    }
-
-    cfg_not_io_driver! {
-        pub(crate) fn shutdown(mut self) {
-            self.spawner.shutdown();
-        }
+    pub(crate) fn shutdown(mut self) {
+        self.spawner.shutdown();
     }
 }
 

tokio/tests/rt_handle_block_on.rs

@@ -1,6 +1,12 @@
 #![warn(rust_2018_idioms)]
 #![cfg(feature = "full")]
 
+// All io tests that deal with shutdown is currently ignored because there are known bugs in with
+// shutting down the io driver while concurrently registering new resources. See
+// https://github.com/tokio-rs/tokio/pull/3569#pullrequestreview-612703467 fo more details.
+//
+// When this has been fixed we want to re-enable these tests.
+
 use std::time::Duration;
 use tokio::runtime::{Handle, Runtime};
 use tokio::sync::mpsc;
@@ -208,6 +214,8 @@ rt_test! {
             .unwrap();
     }
 
+    // All io tests are ignored for now. See above why that is.
+    #[ignore]
     #[test]
     fn tcp_listener_connect_after_shutdown() {
         let rt = rt();
@@ -226,6 +234,8 @@ rt_test! {
         );
     }
 
+    // All io tests are ignored for now. See above why that is.
+    #[ignore]
     #[test]
     fn tcp_listener_connect_before_shutdown() {
         let rt = rt();
@@ -254,6 +264,8 @@ rt_test! {
             .unwrap();
     }
 
+    // All io tests are ignored for now. See above why that is.
+    #[ignore]
     #[test]
     fn udp_stream_bind_after_shutdown() {
         let rt = rt();
@@ -272,6 +284,8 @@ rt_test! {
         );
     }
 
+    // All io tests are ignored for now. See above why that is.
+    #[ignore]
     #[test]
     fn udp_stream_bind_before_shutdown() {
         let rt = rt();
@@ -290,6 +304,8 @@ rt_test! {
         );
     }
 
+    // All io tests are ignored for now. See above why that is.
+    #[ignore]
     #[cfg(unix)]
     #[test]
     fn unix_listener_bind_after_shutdown() {
@@ -310,9 +326,11 @@ rt_test! {
         );
     }
 
+    // All io tests are ignored for now. See above why that is.
+    #[ignore]
     #[cfg(unix)]
     #[test]
-    fn unix_listener_bind_accept_after_shutdown_1() {
+    fn unix_listener_shutdown_after_bind() {
         let rt = rt();
         let _enter = rt.enter();
 
@@ -330,9 +348,11 @@ rt_test! {
         assert_eq!(err.get_ref().unwrap().to_string(), "reactor gone");
     }
 
+    // All io tests are ignored for now. See above why that is.
+    #[ignore]
     #[cfg(unix)]
     #[test]
-    fn unix_listener_bind_accept_after_shutdown_2() {
+    fn unix_listener_shutdown_after_accept() {
         let rt = rt();
         let _enter = rt.enter();