X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fagent-thread.c;h=d1bb122c171d9158b343f504497e5fba2fe64382;hp=6790a63c642bd78bb37484a6c6af0b1af39081c7;hb=e8fcabef14e1e2ce8d159c68c5585931df1216b4;hpb=fefd409b002735b415c5f653cdb2587be454f145

diff --git a/src/bin/lttng-sessiond/agent-thread.c b/src/bin/lttng-sessiond/agent-thread.c
index 6790a63c6..d1bb122c1 100644
--- a/src/bin/lttng-sessiond/agent-thread.c
+++ b/src/bin/lttng-sessiond/agent-thread.c
@@ -16,6 +16,7 @@
  */
 
 #define _GNU_SOURCE
+#define _LGPL_SOURCE
 #include <assert.h>
 
 #include <common/common.h>
@@ -27,6 +28,7 @@
 
 #include "fd-limit.h"
 #include "agent-thread.h"
+#include "agent.h"
 #include "lttng-sessiond.h"
 #include "session.h"
 #include "utils.h"
@@ -60,63 +62,18 @@ static void update_agent_app(struct agent_app *app)
 		if (session->ust_session) {
 			struct agent *agt;
 
+			rcu_read_lock();
 			agt = trace_ust_find_agent(session->ust_session, app->domain);
 			if (agt) {
 				agent_update(agt, app->sock->fd);
 			}
+			rcu_read_unlock();
 		}
 		session_unlock(session);
 	}
 	session_unlock_list();
 }
 
-/*
- * Destroy a agent application by socket.
- */
-static void destroy_agent_app(int sock)
-{
-	struct agent_app *app;
-
-	assert(sock >= 0);
-
-	/*
-	 * Not finding an application is a very important error that should NEVER
-	 * happen. The hash table deletion is ONLY done through this call even on
-	 * thread cleanup.
-	 */
-	rcu_read_lock();
-	app = agent_find_app_by_sock(sock);
-	assert(app);
-	rcu_read_unlock();
-
-	/* RCU read side lock is taken in this function call. */
-	agent_delete_app(app);
-
-	/* The application is freed in a RCU call but the socket is closed here. */
-	agent_destroy_app(app);
-}
-
-/*
- * Cleanup remaining agent apps in the hash table. This should only be called in
- * the exit path of the thread.
- */
-static void clean_agent_apps_ht(void)
-{
-	struct lttng_ht_node_ulong *node;
-	struct lttng_ht_iter iter;
-
-	DBG3("[agent-thread] Cleaning agent apps ht");
-
-	rcu_read_lock();
-	cds_lfht_for_each_entry(agent_apps_ht_by_sock->ht, &iter.iter, node, node) {
-		struct agent_app *app;
-
-		app = caa_container_of(node, struct agent_app, node);
-		destroy_agent_app(app->sock->fd);
-	}
-	rcu_read_unlock();
-}
-
 /*
  * Create and init socket from uri.
  */
@@ -198,6 +155,7 @@ static int handle_registration(struct lttcomm_sock *reg_sock,
 {
 	int ret;
 	pid_t pid;
+	uint32_t major_version, minor_version;
 	ssize_t size;
 	enum lttng_domain_type domain;
 	struct agent_app *app;
@@ -214,11 +172,23 @@ static int handle_registration(struct lttcomm_sock *reg_sock,
 
 	size = new_sock->ops->recvmsg(new_sock, &msg, sizeof(msg), 0);
 	if (size < sizeof(msg)) {
-		ret = -errno;
+		ret = -EINVAL;
 		goto error_socket;
 	}
 	domain = be32toh(msg.domain);
 	pid = be32toh(msg.pid);
+	major_version = be32toh(msg.major_version);
+	minor_version = be32toh(msg.minor_version);
+
+	/* Test communication protocol version of the registring agent. */
+	if (major_version != AGENT_MAJOR_VERSION) {
+		ret = -EINVAL;
+		goto error_socket;
+	}
+	if (minor_version != AGENT_MINOR_VERSION) {
+		ret = -EINVAL;
+		goto error_socket;
+	}
 
 	DBG2("[agent-thread] New registration for pid %d domain %d on socket %d",
 			pid, domain, new_sock->fd);
@@ -291,12 +261,13 @@ void *agent_thread_manage_registration(void *data)
 	}
 
 	while (1) {
-		DBG3("[agent-thread] Manage agent polling on %d fds",
-				LTTNG_POLL_GETNB(&events));
+		DBG3("[agent-thread] Manage agent polling");
 
 		/* Inifinite blocking call, waiting for transmission */
 restart:
 		ret = lttng_poll_wait(&events, -1);
+		DBG3("[agent-thread] Manage agent return from poll on %d fds",
+				LTTNG_POLL_GETNB(&events));
 		if (ret < 0) {
 			/*
 			 * Restart interrupted system call.
@@ -314,6 +285,11 @@ restart:
 			revents = LTTNG_POLL_GETEV(&events, i);
 			pollfd = LTTNG_POLL_GETFD(&events, i);
 
+			if (!revents) {
+				/* No activity for this FD (poll implementation). */
+				continue;
+			}
+
 			/* Thread quit pipe has been closed. Killing thread. */
 			ret = sessiond_check_thread_quit_pipe(pollfd, revents);
 			if (ret) {
@@ -331,7 +307,7 @@ restart:
 					goto error;
 				}
 
-				destroy_agent_app(pollfd);
+				agent_destroy_app_by_sock(pollfd);
 			} else if (revents & (LPOLLIN)) {
 				int new_fd;
 				struct agent_app *app = NULL;
@@ -352,7 +328,7 @@ restart:
 				ret = lttng_poll_add(&events, new_fd,
 						LPOLLERR | LPOLLHUP | LPOLLRDHUP);
 				if (ret < 0) {
-					destroy_agent_app(new_fd);
+					agent_destroy_app_by_sock(new_fd);
 					continue;
 				}
 
@@ -378,11 +354,6 @@ error_tcp_socket:
 error_poll_create:
 	DBG("[agent-thread] is cleaning up and stopping.");
 
-	if (agent_apps_ht_by_sock) {
-		clean_agent_apps_ht();
-		lttng_ht_destroy(agent_apps_ht_by_sock);
-	}
-
 	rcu_thread_offline();
 	rcu_unregister_thread();
 	return NULL;