tests: Make udp_server SMP aware

tests/udp_server.cc

@@ -2,24 +2,23 @@
  * Copyright (C) 2014 Cloudius Systems, Ltd.
  */
 
+#include "core/smp.hh"
 #include "core/app-template.hh"
 #include "core/future-util.hh"
 
 using namespace net;
 using namespace std::chrono_literals;
 
-class server {
+class udp_server {
 private:
     udp_channel _chan;
     timer _stats_timer;
     uint64_t _n_sent {};
 public:
-    void start() {
-        ipv4_addr listen_addr{10000};
+    void start(uint16_t port) {
+        ipv4_addr listen_addr{port};
         _chan = engine.net().make_udp_channel(listen_addr);
 
-        std::cout << "Listening on " << listen_addr << std::endl;
-
         _stats_timer.set_callback([this] {
             std::cout << "Out: " << _n_sent << " pps" << std::endl;
             _n_sent = 0;
@@ -36,8 +35,20 @@ public:
     }
 };
 
+namespace bpo = boost::program_options;
+
 int main(int ac, char ** av) {
-    server s;
     app_template app;
-    return app.run(ac, av, [&s] { s.start(); });
+    app.add_options()
+        ("port", bpo::value<uint16_t>()->default_value(10000), "UDP server port") ;
+    return app.run(ac, av, [&] {
+        auto&& config = app.configuration();
+        uint16_t port = config["port"].as<uint16_t>();
+        auto server = new distributed<udp_server>;
+        server->start().then([server = std::move(server), port] () mutable {
+            server->invoke_on_all(&udp_server::start, port);
+        }).then([port] {
+            std::cout << "Seastar UDP server listening on port " << port << " ...\n";
+        });
+    });
 }