From a37c1ee8ea85860fdaa963ee3f50b86b3585b01d Mon Sep 17 00:00:00 2001
From: Stjepan Glavina <stjepang@gmail.com>
Date: Mon, 25 May 2020 23:31:11 +0200
Subject: [PATCH] Drop locks before waking tasks

---
 src/reactor.rs | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/src/reactor.rs b/src/reactor.rs
index 9c6089f..a9ceef4 100644
--- a/src/reactor.rs
+++ b/src/reactor.rs
@@ -224,6 +224,9 @@ impl Reactor {
             Some(Duration::from_secs(0))
         };
 
+        // Drop the lock before waking.
+        drop(timers);
+
         // Wake up tasks waiting on timers.
         for (_, waker) in ready {
             waker.wake();
@@ -273,6 +276,7 @@ impl ReactorLock<'_> {
                 Ok(_) => {
                     // Iterate over sources in the event list.
                     let sources = self.reactor.sources.lock();
+                    let mut ready = Vec::new();
 
                     for ev in self.events.iter() {
                         // Check if there is a source in the table with this key.
@@ -281,20 +285,24 @@ impl ReactorLock<'_> {
 
                             // Wake readers if a readability event was emitted.
                             if ev.readable {
-                                for w in wakers.readers.drain(..) {
-                                    w.wake();
-                                }
+                                ready.append(&mut wakers.readers);
                             }
 
                             // Wake writers if a writability event was emitted.
                             if ev.writable {
-                                for w in wakers.writers.drain(..) {
-                                    w.wake();
-                                }
+                                ready.append(&mut wakers.writers);
                             }
                         }
                     }
 
+                    // Drop the lock before waking.
+                    drop(sources);
+
+                    // Wake up tasks waiting on I/O.
+                    for waker in ready {
+                        waker.wake();
+                    }
+
                     return Ok(());
                 }