From a5c2b4a24f4b40681d9e27c8d7c3013014a42665 Mon Sep 17 00:00:00 2001
From: "Alan M. Carroll" <amc@apache.org>
Date: Mon, 10 May 2021 13:50:10 -0500
Subject: [PATCH] EPoll error capture - store in NetEvent for later processing.

---
 iocore/net/NetEvent.h |  1 +
 iocore/net/UnixNet.cc | 20 +++++++++++---------
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/iocore/net/NetEvent.h b/iocore/net/NetEvent.h
index 94e96fedda9..de5ed5f1e7f 100644
--- a/iocore/net/NetEvent.h
+++ b/iocore/net/NetEvent.h
@@ -91,6 +91,7 @@ class NetEvent
     struct {
       unsigned int got_local_addr : 1;
       unsigned int shutdown : 2;
+      unsigned int epoll_error : 1;
     } f;
   };
 };
diff --git a/iocore/net/UnixNet.cc b/iocore/net/UnixNet.cc
index 19ea5aee750..5356d49f5ef 100644
--- a/iocore/net/UnixNet.cc
+++ b/iocore/net/UnixNet.cc
@@ -507,27 +507,29 @@ NetHandler::waitForActivity(ink_hrtime timeout)
       if (cop_list.in(ne)) {
         cop_list.remove(ne);
       }
-      if (get_ev_events(pd, x) & (EVENTIO_READ | EVENTIO_ERROR)) {
+      auto flags        = get_ev_events(pd, x);
+      ne->f.epoll_error = (0 != (flags & EVENTIO_ERROR));
+      if (flags & (EVENTIO_READ | EVENTIO_ERROR)) {
         ne->read.triggered = 1;
         if (!read_ready_list.in(ne)) {
           read_ready_list.enqueue(ne);
-        } else if (get_ev_events(pd, x) & EVENTIO_ERROR) {
+        } else if (flags & EVENTIO_ERROR) {
           // check for unhandled epoll events that should be handled
-          Debug("iocore_net_main", "Unhandled epoll event on read: 0x%04x read.enabled=%d closed=%d read.netready_queue=%d",
-                get_ev_events(pd, x), ne->read.enabled, ne->closed, read_ready_list.in(ne));
+          Debug("iocore_net_main", "Unhandled epoll event on read: 0x%04x read.enabled=%d closed=%d read.netready_queue=%d", flags,
+                ne->read.enabled, ne->closed, read_ready_list.in(ne));
         }
       }
-      if (get_ev_events(pd, x) & (EVENTIO_WRITE | EVENTIO_ERROR)) {
+      if (flags & (EVENTIO_WRITE | EVENTIO_ERROR)) {
         ne->write.triggered = 1;
         if (!write_ready_list.in(ne)) {
           write_ready_list.enqueue(ne);
-        } else if (get_ev_events(pd, x) & EVENTIO_ERROR) {
+        } else if (flags & EVENTIO_ERROR) {
           // check for unhandled epoll events that should be handled
           Debug("iocore_net_main", "Unhandled epoll event on write: 0x%04x write.enabled=%d closed=%d write.netready_queue=%d",
-                get_ev_events(pd, x), ne->write.enabled, ne->closed, write_ready_list.in(ne));
+                flags, ne->write.enabled, ne->closed, write_ready_list.in(ne));
         }
-      } else if (!(get_ev_events(pd, x) & EVENTIO_READ)) {
-        Debug("iocore_net_main", "Unhandled epoll event: 0x%04x", get_ev_events(pd, x));
+      } else if (!(flags & EVENTIO_READ)) {
+        Debug("iocore_net_main", "Unhandled epoll event: 0x%04x", flags);
       }
     } else if (epd->type == EVENTIO_DNS_CONNECTION) {
       if (epd->data.dnscon != nullptr) {