Use free running metadata channel key between sessiond and kernel consumer

[lttng-tools.git] / src / bin / lttng-relayd / main.c

diff --git a/src/bin/lttng-relayd/main.c b/src/bin/lttng-relayd/main.c
index 7b313818e5c09a5719339740f47b2787304d461b..cd4f058bf0243df63dd78e573e97fca202b751d3 100644 (file)
--- a/src/bin/lttng-relayd/main.c
+++ b/src/bin/lttng-relayd/main.c
@@ -70,6 +70,15 @@
 #include "stream.h"
 #include "connection.h"
 #include "tracefile-array.h"
+#include "tcp_keep_alive.h"
+
+static const char *help_msg =
+#ifdef LTTNG_EMBED_HELP
+#include <lttng-relayd.8.h>
+#else
+NULL
+#endif
+;
 
 /* command line options */
 char *opt_output_path;
@@ -250,9 +259,9 @@ static int set_option(int opt, const char *arg, const char *optname)
                }
                break;
        case 'h':
-               ret = utils_show_man_page(8, "lttng-relayd");
+               ret = utils_show_help(8, "lttng-relayd", help_msg);
                if (ret) {
-                       ERR("Cannot view man page lttng-relayd(8)");
+                       ERR("Cannot show --help for `lttng-relayd`");
                        perror("exec");
                }
                exit(EXIT_FAILURE);
@@ -891,6 +900,15 @@ restart:
                                        lttcomm_destroy_sock(newsock);
                                        goto error;
                                }
+
+                               ret = socket_apply_keep_alive_config(newsock->fd);
+                               if (ret < 0) {
+                                       ERR("Failed to apply TCP keep-alive configuration on socket (%i)",
+                                                       newsock->fd);
+                                       lttcomm_destroy_sock(newsock);
+                                       goto error;
+                               }
+
                                new_conn = connection_create(newsock, type);
                                if (!new_conn) {
                                        lttcomm_destroy_sock(newsock);
@@ -969,12 +987,16 @@ static void *relay_thread_dispatcher(void *data)
 
        health_code_update();
 
-       while (!CMM_LOAD_SHARED(dispatch_thread_exit)) {
+       for (;;) {
                health_code_update();
 
                /* Atomically prepare the queue futex */
                futex_nto1_prepare(&relay_conn_queue.futex);
 
+               if (CMM_LOAD_SHARED(dispatch_thread_exit)) {
+                       break;
+               }
+
                do {
                        health_code_update();
 
@@ -1579,6 +1601,7 @@ static int relay_send_version(struct lttcomm_relayd_hdr *recv_hdr,
 {
        int ret;
        struct lttcomm_relayd_version reply, msg;
+       bool compatible = true;
 
        conn->version_check_done = 1;
 
@@ -1603,9 +1626,7 @@ static int relay_send_version(struct lttcomm_relayd_hdr *recv_hdr,
        if (reply.major != be32toh(msg.major)) {
                DBG("Incompatible major versions (%u vs %u), deleting session",
                                reply.major, be32toh(msg.major));
-               connection_put(conn);
-               ret = 0;
-               goto end;
+               compatible = false;
        }
 
        conn->major = reply.major;
@@ -1624,6 +1645,11 @@ static int relay_send_version(struct lttcomm_relayd_hdr *recv_hdr,
                ERR("Relay sending version");
        }
 
+       if (!compatible) {
+               ret = -1;
+               goto end;
+       }
+
        DBG("Version check done using protocol %u.%u", conn->major,
                        conn->minor);
 
@@ -2937,6 +2963,12 @@ exit_init_data:
        health_app_destroy(health_relayd);
 exit_health_app_create:
 exit_options:
+       /*
+        * Wait for all pending call_rcu work to complete before tearing
+        * down data structures. call_rcu worker may be trying to
+        * perform lookups in those structures.
+        */
+       rcu_barrier();
        relayd_cleanup();
 
        /* Ensure all prior call_rcu are done. */