From 638f8a2cbc4c6a5287427bac1c88a1dcc5f03430 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ond=C5=99ej=20Kuzn=C3=ADk?= <okuznik@symas.com>
Date: Fri, 20 Apr 2018 13:28:10 +0100
Subject: [PATCH] Tighten checks on retry management

---
 servers/lloadd/backend.c | 21 +++++++++++++++++++++
 servers/lloadd/daemon.c  | 17 ++++++++++-------
 2 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/servers/lloadd/backend.c b/servers/lloadd/backend.c
index 872cafe1da..346b32fa9f 100644
--- a/servers/lloadd/backend.c
+++ b/servers/lloadd/backend.c
@@ -484,9 +484,29 @@ backend_connect_task( void *ctx, void *arg )
     return NULL;
 }
 
+/*
+ * Needs exclusive access to the backend.
+ */
 void
 backend_reset( LloadBackend *b )
 {
+    if ( b->b_cookie ) {
+        int rc;
+        rc = ldap_pvt_thread_pool_retract( b->b_cookie );
+        assert( rc == 1 );
+        b->b_cookie = NULL;
+        b->b_opening--;
+    }
+    if ( event_pending( b->b_retry_event, EV_TIMEOUT, NULL ) ) {
+        assert( b->b_failed );
+        event_del( b->b_retry_event );
+        b->b_opening--;
+    }
+    if ( b->b_dns_req ) {
+        evdns_getaddrinfo_cancel( b->b_dns_req );
+        b->b_dns_req = NULL;
+        b->b_opening--;
+    }
     while ( !LDAP_LIST_EMPTY( &b->b_connecting ) ) {
         LloadPendingConnection *pending = LDAP_LIST_FIRST( &b->b_connecting );
 
@@ -569,6 +589,7 @@ lload_backend_destroy( LloadBackend *b )
             "destroying backend uri='%s', numconns=%d, numbindconns=%d\n",
             b->b_uri.bv_val, b->b_numconns, b->b_numbindconns );
 
+    b->b_numconns = b->b_numbindconns = 0;
     backend_reset( b );
 
     LDAP_CIRCLEQ_REMOVE( &backend, b, b_next );
diff --git a/servers/lloadd/daemon.c b/servers/lloadd/daemon.c
index 4deb545872..bb449d1300 100644
--- a/servers/lloadd/daemon.c
+++ b/servers/lloadd/daemon.c
@@ -1389,6 +1389,12 @@ lloadd_daemon( struct event_base *daemon_base )
     destroy_listeners();
 
     /* TODO: Mark upstream connections closing */
+    LDAP_CIRCLEQ_FOREACH ( b, &backend, b_next ) {
+        ldap_pvt_thread_mutex_lock( &b->b_mutex );
+        b->b_numconns = b->b_numbindconns = 0;
+        backend_reset( b );
+        ldap_pvt_thread_mutex_unlock( &b->b_mutex );
+    }
 
     for ( i = 0; i < lload_daemon_threads; i++ ) {
         /*
@@ -1497,12 +1503,6 @@ lload_handle_backend_invalidation( LloadChange *change )
                 &connection_pool, handle_pdus, backend_conn_cb, b );
         ldap_pvt_thread_pool_walk(
                 &connection_pool, upstream_bind, backend_conn_cb, b );
-        /* Drop the connection task if it's queued */
-        if ( b->b_cookie ) {
-            int rc = ldap_pvt_thread_pool_retract( b->b_cookie );
-            assert( rc == 1 );
-            b->b_opening--;
-        }
         lload_backend_destroy( b );
         return;
     }
@@ -1586,7 +1586,10 @@ lload_handle_backend_invalidation( LloadChange *change )
                 b->b_opening--;
                 need_close--;
             }
-            event_del( b->b_retry_event );
+            if ( event_pending( b->b_retry_event, EV_TIMEOUT, NULL ) ) {
+                event_del( b->b_retry_event );
+                b->b_opening--;
+            }
             assert( b->b_opening == 0 );
         }