nghttpx: Add --listener-disable-timeout option

src/shrpx.cc

@@ -151,6 +151,11 @@ namespace {
 void evlistener_errorcb(evconnlistener *listener, void *ptr)
 {
   LOG(ERROR) << "Accepting incoming connection failed";
+
+  auto listener_handler = static_cast<ListenHandler*>(ptr);
+
+  listener_handler->disable_evlistener_temporary
+    (&get_config()->listener_disable_timeout);
 }
 } // namespace
 
@@ -449,6 +454,8 @@ void graceful_shutdown_signal_cb(evutil_socket_t sig, short events, void *arg)
     LOG(INFO) << "Graceful shutdown signal received";
   }
 
+  worker_config->graceful_shutdown = true;
+
   listener_handler->disable_evlistener();
 
   // After disabling accepting new connection, disptach incoming
@@ -456,8 +463,6 @@ void graceful_shutdown_signal_cb(evutil_socket_t sig, short events, void *arg)
 
   listener_handler->accept_pending_connection();
 
-  worker_config->graceful_shutdown = true;
-
   listener_handler->graceful_shutdown_worker();
 }
 } // namespace
@@ -809,6 +814,7 @@ void fill_default_config()
   mod_config()->argc = 0;
   mod_config()->argv = nullptr;
   mod_config()->max_downstream_connections = 100;
+  mod_config()->listener_disable_timeout = {0, 0};
 }
 } // namespace
 
@@ -977,6 +983,12 @@ Timeout:
                      connection.
                      Default: )"
       << get_config()->downstream_idle_read_timeout.tv_sec << R"(
+  --listener-disable-timeout=<SEC>
+                     After  accepting  connection  failed,  connection
+                     listener is disabled for a given time in seconds.
+                     Specifying 0 disables this feature.
+                     Default: )"
+      << get_config()->listener_disable_timeout.tv_sec << R"(
   --backend-http-proxy-uri=<URI>
                      Specify     proxy     URI     in     the     form
                      http://[<USER>:<PASS>@]<PROXY>:<PORT>.     If   a
@@ -1297,6 +1309,7 @@ int main(int argc, char **argv)
       {"stream-write-timeout", required_argument, &flag, 61},
       {"no-location-rewrite", no_argument, &flag, 62},
       {"backend-connections-per-frontend", required_argument, &flag, 63},
+      {"listener-disable-timeout", required_argument, &flag, 64},
       {nullptr, 0, nullptr, 0 }
     };
 
@@ -1590,6 +1603,10 @@ int main(int argc, char **argv)
         cmdcfgs.emplace_back(SHRPX_OPT_BACKEND_CONNECTIONS_PER_FRONTEND,
                              optarg);
         break;
+      case 64:
+        // --listener-disable-timeout
+        cmdcfgs.emplace_back(SHRPX_OPT_LISTENER_DISABLE_TIMEOUT, optarg);
+        break;
       default:
         break;
       }

src/shrpx_config.cc

@@ -131,6 +131,7 @@ const char SHRPX_OPT_WORKER_FRONTEND_CONNECTIONS[] =
 const char SHRPX_OPT_NO_LOCATION_REWRITE[] = "no-location-rewrite";
 const char SHRPX_OPT_BACKEND_CONNECTIONS_PER_FRONTEND[] =
   "backend-connections-per-frontend";
+const char SHRPX_OPT_LISTENER_DISABLE_TIMEOUT[] = "listener-disable-timeout";
 
 namespace {
 Config *config = nullptr;
@@ -897,6 +898,13 @@ int parse_config(const char *opt, const char *optarg)
     return 0;
   }
 
+  if(util::strieq(opt, SHRPX_OPT_LISTENER_DISABLE_TIMEOUT)) {
+    timeval tv = {strtol(optarg, nullptr, 10), 0};
+    mod_config()->listener_disable_timeout = tv;
+
+    return 0;
+  }
+
   if(util::strieq(opt, "conf")) {
     LOG(WARNING) << "conf is ignored";
 

src/shrpx_config.h

@@ -120,6 +120,7 @@ extern const char SHRPX_OPT_ADD_RESPONSE_HEADER[];
 extern const char SHRPX_OPT_WORKER_FRONTEND_CONNECTIONS[];
 extern const char SHRPX_OPT_NO_LOCATION_REWRITE[];
 extern const char SHRPX_OPT_BACKEND_CONNECTIONS_PER_FRONTEND[];
+extern const char SHRPX_OPT_LISTENER_DISABLE_TIMEOUT[];
 
 union sockaddr_union {
   sockaddr sa;
@@ -173,6 +174,7 @@ struct Config {
   timeval stream_read_timeout;
   timeval stream_write_timeout;
   timeval downstream_idle_read_timeout;
+  timeval listener_disable_timeout;
   std::unique_ptr<char[]> host;
   std::unique_ptr<char[]> private_key_file;
   std::unique_ptr<char[]> private_key_passwd;

src/shrpx_listen_handler.cc

@@ -45,6 +45,21 @@ using namespace nghttp2;
 
 namespace shrpx {
 
+namespace {
+void evlistener_disable_cb(evutil_socket_t fd, short events, void *arg)
+{
+  auto listener_handler = static_cast<ListenHandler*>(arg);
+
+  // If we are in graceful shutdown period, we must not enable
+  // evlisteners again.
+  if(worker_config->graceful_shutdown) {
+    return;
+  }
+
+  listener_handler->enable_evlistener();
+}
+} // namespace
+
 ListenHandler::ListenHandler(event_base *evbase, SSL_CTX *sv_ssl_ctx,
                              SSL_CTX *cl_ssl_ctx)
   : evbase_(evbase),
@@ -54,6 +69,8 @@ ListenHandler::ListenHandler(event_base *evbase, SSL_CTX *sv_ssl_ctx,
                       (evbase, get_config()->worker_rate_limit_cfg)),
     evlistener4_(nullptr),
     evlistener6_(nullptr),
+    evlistener_disable_timerev_(evtimer_new(evbase,
+                                            evlistener_disable_cb, this)),
     worker_stat_(util::make_unique<WorkerStat>()),
     num_worker_shutdown_(0),
     worker_round_robin_cnt_(0)
@@ -295,6 +312,17 @@ evconnlistener* ListenHandler::get_evlistener6() const
   return evlistener6_;
 }
 
+void ListenHandler::enable_evlistener()
+{
+  if(evlistener4_) {
+    evconnlistener_enable(evlistener4_);
+  }
+
+  if(evlistener6_) {
+    evconnlistener_enable(evlistener6_);
+  }
+}
+
 void ListenHandler::disable_evlistener()
 {
   if(evlistener4_) {
@@ -306,6 +334,24 @@ void ListenHandler::disable_evlistener()
   }
 }
 
+void ListenHandler::disable_evlistener_temporary(const timeval *timeout)
+{
+  int rv;
+
+  if(timeout->tv_sec == 0 ||
+     evtimer_pending(evlistener_disable_timerev_, nullptr)) {
+    return;
+  }
+
+  disable_evlistener();
+
+  rv = evtimer_add(evlistener_disable_timerev_, timeout);
+
+  if(rv < 0) {
+    LOG(ERROR) << "evtimer_add for evlistener_disable_timerev_ failed";
+  }
+}
+
 namespace {
 void perform_accept_pending_connection(ListenHandler *listener_handler,
                                        evconnlistener *listener)

src/shrpx_listen_handler.h

@@ -73,7 +73,9 @@ public:
   evconnlistener* get_evlistener4() const;
   void set_evlistener6(evconnlistener *evlistener6);
   evconnlistener* get_evlistener6() const;
+  void enable_evlistener();
   void disable_evlistener();
+  void disable_evlistener_temporary(const timeval *timeout);
   void accept_pending_connection();
   void graceful_shutdown_worker();
   void join_worker();
@@ -92,6 +94,7 @@ private:
   bufferevent_rate_limit_group *rate_limit_group_;
   evconnlistener *evlistener4_;
   evconnlistener *evlistener6_;
+  event *evlistener_disable_timerev_;
   std::unique_ptr<WorkerStat> worker_stat_;
   size_t num_worker_shutdown_;
   unsigned int worker_round_robin_cnt_;