Fix: wait for the completion of implicit session rotations

[lttng-tools.git] / src / bin / lttng-sessiond / client.c

diff --git a/src/bin/lttng-sessiond/client.c b/src/bin/lttng-sessiond/client.c
index 4565a18c31efe55f70e94293cd03d6962d574af4..aea667cd116d2fea0132bffec7782b065fc71536 100644 (file)
--- a/src/bin/lttng-sessiond/client.c
+++ b/src/bin/lttng-sessiond/client.c
@@ -706,10 +706,12 @@ static int send_unix_sock(int sock, void *buf, size_t len)
  * Return any error encountered or 0 for success.
  *
  * "sock" is only used for special-case var. len data.
+ * A command may assume the ownership of the socket, in which case its value
+ * should be set to -1.
  *
  * Should *NOT* be called with RCU read-side lock held.
  */
-static int process_client_msg(struct command_ctx *cmd_ctx, int sock,
+static int process_client_msg(struct command_ctx *cmd_ctx, int *sock,
                int *sock_error)
 {
        int ret = LTTNG_OK;
@@ -1108,13 +1110,13 @@ skip_domain:
                        cmd_ctx->lsm->u.context.ctx.u.app_ctx.ctx_name =
                                        context_name;
 
-                       ret = lttcomm_recv_unix_sock(sock, provider_name,
+                       ret = lttcomm_recv_unix_sock(*sock, provider_name,
                                        provider_name_len);
                        if (ret < 0) {
                                goto error_add_context;
                        }
 
-                       ret = lttcomm_recv_unix_sock(sock, context_name,
+                       ret = lttcomm_recv_unix_sock(*sock, context_name,
                                        context_name_len);
                        if (ret < 0) {
                                goto error_add_context;
@@ -1167,7 +1169,7 @@ error_add_context:
 
                        DBG("Discarding disable event command payload of size %zu", count);
                        while (count) {
-                               ret = lttcomm_recv_unix_sock(sock, data,
+                               ret = lttcomm_recv_unix_sock(*sock, data,
                                        count > sizeof(data) ? sizeof(data) : count);
                                if (ret < 0) {
                                        goto error;
@@ -1225,7 +1227,7 @@ error_add_context:
 
                        DBG("Receiving var len exclusion event list from client ...");
                        exclusion->count = count;
-                       ret = lttcomm_recv_unix_sock(sock, exclusion->names,
+                       ret = lttcomm_recv_unix_sock(*sock, exclusion->names,
                                        count * LTTNG_SYMBOL_NAME_LEN);
                        if (ret <= 0) {
                                DBG("Nothing recv() from client var len data... continuing");
@@ -1256,7 +1258,7 @@ error_add_context:
 
                        /* Receive var. len. data */
                        DBG("Receiving var len filter's expression from client ...");
-                       ret = lttcomm_recv_unix_sock(sock, filter_expression,
+                       ret = lttcomm_recv_unix_sock(*sock, filter_expression,
                                expression_len);
                        if (ret <= 0) {
                                DBG("Nothing recv() from client var len data... continuing");
@@ -1289,7 +1291,7 @@ error_add_context:
 
                        /* Receive var. len. data */
                        DBG("Receiving var len filter's bytecode from client ...");
-                       ret = lttcomm_recv_unix_sock(sock, bytecode, bytecode_len);
+                       ret = lttcomm_recv_unix_sock(*sock, bytecode, bytecode_len);
                        if (ret <= 0) {
                                DBG("Nothing recv() from client var len data... continuing");
                                *sock_error = 1;
@@ -1323,7 +1325,7 @@ error_add_context:
 
                if (cmd_ctx->lsm->u.enable.userspace_probe_location_len > 0) {
                        /* Expect a userspace probe description. */
-                       ret = receive_userspace_probe(cmd_ctx, sock, sock_error, ev);
+                       ret = receive_userspace_probe(cmd_ctx, *sock, sock_error, ev);
                        if (ret) {
                                free(filter_expression);
                                free(bytecode);
@@ -1476,7 +1478,7 @@ error_add_context:
 
                /* Receive variable len data */
                DBG("Receiving %zu URI(s) from client ...", nb_uri);
-               ret = lttcomm_recv_unix_sock(sock, uris, len);
+               ret = lttcomm_recv_unix_sock(*sock, uris, len);
                if (ret <= 0) {
                        DBG("No URIs received from client... continuing");
                        *sock_error = 1;
@@ -1521,7 +1523,8 @@ error_add_context:
        case LTTNG_DESTROY_SESSION:
        {
                ret = cmd_destroy_session(cmd_ctx->session,
-                               notification_thread_handle);
+                               notification_thread_handle,
+                               sock);
                break;
        }
        case LTTNG_LIST_DOMAINS:
@@ -1760,7 +1763,7 @@ error_add_context:
                struct lttng_session_descriptor *return_descriptor = NULL;
 
                lttng_dynamic_buffer_init(&payload);
-               ret = cmd_create_session(cmd_ctx, sock, &return_descriptor);
+               ret = cmd_create_session(cmd_ctx, *sock, &return_descriptor);
                if (ret != LTTNG_OK) {
                        goto error;
                }
@@ -1809,13 +1812,13 @@ error_add_context:
        }
        case LTTNG_REGISTER_TRIGGER:
        {
-               ret = cmd_register_trigger(cmd_ctx, sock,
+               ret = cmd_register_trigger(cmd_ctx, *sock,
                                notification_thread_handle);
                break;
        }
        case LTTNG_UNREGISTER_TRIGGER:
        {
-               ret = cmd_unregister_trigger(cmd_ctx, sock,
+               ret = cmd_unregister_trigger(cmd_ctx, *sock,
                                notification_thread_handle);
                break;
        }
@@ -1934,6 +1937,7 @@ setup_error:
        if (cmd_ctx->session) {
                session_unlock(cmd_ctx->session);
                session_put(cmd_ctx->session);
+               cmd_ctx->session = NULL;
        }
        if (need_tracing_session) {
                session_unlock_list();
@@ -2178,14 +2182,16 @@ static void *thread_manage_clients(void *data)
                 * informations for the client. The command context struct contains
                 * everything this function may needs.
                 */
-               ret = process_client_msg(cmd_ctx, sock, &sock_error);
+               ret = process_client_msg(cmd_ctx, &sock, &sock_error);
                rcu_thread_offline();
                if (ret < 0) {
-                       ret = close(sock);
-                       if (ret) {
-                               PERROR("close");
-                       }
-                       sock = -1;
+                       if (sock >= 0) {
+                               ret = close(sock);
+                               if (ret) {
+                                       PERROR("close");
+                               }
+                        }
+                        sock = -1;
                        /*
                         * TODO: Inform client somehow of the fatal error. At
                         * this point, ret < 0 means that a zmalloc failed
@@ -2211,21 +2217,24 @@ static void *thread_manage_clients(void *data)
 
                health_code_update();
 
-               DBG("Sending response (size: %d, retcode: %s (%d))",
-                               cmd_ctx->lttng_msg_size,
-                               lttng_strerror(-cmd_ctx->llm->ret_code),
-                               cmd_ctx->llm->ret_code);
-               ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
-               if (ret < 0) {
-                       ERR("Failed to send data back to client");
-               }
+               if (sock >= 0) {
+                       DBG("Sending response (size: %d, retcode: %s (%d))",
+                                       cmd_ctx->lttng_msg_size,
+                                       lttng_strerror(-cmd_ctx->llm->ret_code),
+                                       cmd_ctx->llm->ret_code);
+                       ret = send_unix_sock(sock, cmd_ctx->llm,
+                                       cmd_ctx->lttng_msg_size);
+                       if (ret < 0) {
+                               ERR("Failed to send data back to client");
+                       }
 
-               /* End of transmission */
-               ret = close(sock);
-               if (ret) {
-                       PERROR("close");
-               }
-               sock = -1;
+                       /* End of transmission */
+                       ret = close(sock);
+                       if (ret) {
+                               PERROR("close");
+                       }
+                }
+                sock = -1;
 
                clean_command_ctx(&cmd_ctx);