3 files changed, 14 insertions, 8 deletions
diff --git a/src/networking.c b/src/networking.c
index 0dfc0767d..82c763c95 100644
--- a/src/networking.c
+++ b/src/networking.c
@@ -67,6 +67,16 @@ int listMatchObjects(void *a, void *b) {
     return equalStringObjects(a,b);
 }
 
+/* This function links the client to the global linked list of clients.
+ * unlinkClient() does the opposite, among other things. */
+void linkClient(client *c) {
+    listAddNodeTail(server.clients,c);
+    /* Note that we remember the linked list node where the client is stored,
+     * this way removing the client in unlinkClient() will not require
+     * a linear scan, but just a constant time operation. */
+    c->client_list_node = listLast(server.clients);
+}
+
 client *createClient(int fd) {
     client *c = zmalloc(sizeof(client));
 
@@ -133,14 +143,10 @@ client *createClient(int fd) {
     c->pubsub_channels = dictCreate(&objectKeyPointerValueDictType,NULL);
     c->pubsub_patterns = listCreate();
     c->peerid = NULL;
+    c->client_list_node = NULL;
     listSetFreeMethod(c->pubsub_patterns,decrRefCountVoid);
     listSetMatchMethod(c->pubsub_patterns,listMatchObjects);
-    if (fd != -1) {
-        listAddNodeTail(server.clients,c);
-        c->client_list_node = listLast(server.clients);
-    } else {
-        c->client_list_node = NULL;
-    }
+    if (fd != -1) linkClient(c);
     initClientMultiState(c);
     return c;
 }
diff --git a/src/replication.c b/src/replication.c
index 773d6e704..17a8bb357 100644
--- a/src/replication.c
+++ b/src/replication.c
@@ -2214,8 +2214,7 @@ void replicationResurrectCachedMaster(int newfd) {
     server.repl_down_since = 0;
 
     /* Re-add to the list of clients. */
-    listAddNodeTail(server.clients,server.master);
-    server.master->client_list_node = listLast(server.clients);
+    linkClient(server.master);
     if (aeCreateFileEvent(server.el, newfd, AE_READABLE,
                           readQueryFromClient, server.master)) {
         serverLog(LL_WARNING,"Error resurrecting the cached master, impossible to add the readable handler: %s", strerror(errno));
diff --git a/src/server.h b/src/server.h
index 2100d7071..7b0d22eaf 100644
--- a/src/server.h
+++ b/src/server.h
@@ -1394,6 +1394,7 @@ int handleClientsWithPendingWrites(void);
 int clientHasPendingReplies(client *c);
 void unlinkClient(client *c);
 int writeToClient(int fd, client *c, int handler_installed);
+void linkClient(client *c);
 
 #ifdef __GNUC__
 void addReplyErrorFormat(client *c, const char *fmt, ...)