Merge remote-tracking branch 'upstream/master' into handshaker_api

1 files changed, 17 insertions, 8 deletions

diff --git a/src/core/lib/iomgr/tcp_server_posix.c b/src/core/lib/iomgr/tcp_server_posix.c
index 38ebd2dbcb..ea8d241154 100644
--- a/src/core/lib/iomgr/tcp_server_posix.c
+++ b/src/core/lib/iomgr/tcp_server_posix.c
@@ -90,10 +90,12 @@ struct grpc_tcp_listener {
   grpc_closure read_closure;
   grpc_closure destroyed_closure;
   struct grpc_tcp_listener *next;
-  /* When we add a listener, more than one can be created, mainly because of
-     IPv6. A sibling will still be in the normal list, but will be flagged
-     as such. Any action, such as ref or unref, will affect all of the
-     siblings in the list. */
+  /* sibling is a linked list of all listeners for a given port. add_port and
+     clone_port place all new listeners in the same sibling list. A member of
+     the 'sibling' list is also a member of the 'next' list. The head of each
+     sibling list has is_sibling==0, and subsequent members of sibling lists
+     have is_sibling==1. is_sibling allows separate sibling lists to be
+     identified while iterating through 'next'. */
   struct grpc_tcp_listener *sibling;
   int is_sibling;
 };
@@ -306,7 +308,7 @@ static grpc_error *prepare_socket(int fd, const struct sockaddr *addr,
 
   GPR_ASSERT(fd >= 0);
 
-  if (so_reuseport) {
+  if (so_reuseport && !grpc_is_unix_socket(addr)) {
     err = grpc_set_socket_reuse_port(fd, 1);
     if (err != GRPC_ERROR_NONE) goto error;
   }
@@ -480,6 +482,9 @@ static grpc_error *add_socket_to_server(grpc_tcp_server *s, int fd,
   return err;
 }
 
+/* Insert count new listeners after listener. Every new listener will have the
+   same listen address as listener (SO_REUSEPORT must be enabled). Every new
+   listener is a sibling of listener. */
 static grpc_error *clone_port(grpc_tcp_listener *listener, unsigned count) {
   grpc_tcp_listener *sp = NULL;
   char *addr_str;
@@ -506,6 +511,11 @@ static grpc_error *clone_port(grpc_tcp_listener *listener, unsigned count) {
     sp = gpr_malloc(sizeof(grpc_tcp_listener));
     sp->next = listener->next;
     listener->next = sp;
+    /* sp (the new listener) is a sibling of 'listener' (the original
+       listener). */
+    sp->is_sibling = 1;
+    sp->sibling = listener->sibling;
+    listener->sibling = sp;
     sp->server = listener->server;
     sp->fd = fd;
     sp->emfd = grpc_fd_create(fd, name);
@@ -514,8 +524,6 @@ static grpc_error *clone_port(grpc_tcp_listener *listener, unsigned count) {
     sp->port = port;
     sp->port_index = listener->port_index;
     sp->fd_index = listener->fd_index + count - i;
-    sp->is_sibling = 1;
-    sp->sibling = listener->is_sibling ? listener->sibling : listener;
     GPR_ASSERT(sp->emfd);
     while (listener->server->tail->next != NULL) {
       listener->server->tail = listener->server->tail->next;
@@ -685,7 +693,8 @@ void grpc_tcp_server_start(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s,
   s->pollset_count = pollset_count;
   sp = s->head;
   while (sp != NULL) {
-    if (s->so_reuseport && pollset_count > 1) {
+    if (s->so_reuseport && !grpc_is_unix_socket(&sp->addr.sockaddr) &&
+        pollset_count > 1) {
       GPR_ASSERT(GRPC_LOG_IF_ERROR(
           "clone_port", clone_port(sp, (unsigned)(pollset_count - 1))));
       for (i = 0; i < pollset_count; i++) {