X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=libust%2Flttng-ust-comm.c;h=6bf9e2b5b350ebb2936507a054a1236c578f9b7c;hb=a51070bbd35a914f8bf83d774ea92c23e3e059b4;hp=2fd165730abef212696e2fcc0c1aa3071a25d036;hpb=37ed587a8b9aea32c383058b4765a5730497d74a;p=lttng-ust.git

diff --git a/libust/lttng-ust-comm.c b/libust/lttng-ust-comm.c
index 2fd16573..6bf9e2b5 100644
--- a/libust/lttng-ust-comm.c
+++ b/libust/lttng-ust-comm.c
@@ -217,6 +217,9 @@ int handle_register_done(struct sock_info *sock_info)
 	if (sock_info->constructor_sem_posted)
 		return 0;
 	sock_info->constructor_sem_posted = 1;
+	if (uatomic_read(&sem_count) <= 0) {
+		return 0;
+	}
 	ret = uatomic_add_return(&sem_count, -1);
 	if (ret == 0) {
 		ret = sem_post(&constructor_wait);
@@ -232,6 +235,7 @@ int handle_message(struct sock_info *sock_info,
 	int ret = 0;
 	const struct objd_ops *ops;
 	struct lttcomm_ust_reply lur;
+	int shm_fd, wait_fd;
 
 	ust_lock();
 
@@ -277,10 +281,53 @@ end:
 	if (ret >= 0) {
 		lur.ret_code = LTTCOMM_OK;
 	} else {
-		lur.ret_code = LTTCOMM_SESSION_FAIL;
+		//lur.ret_code = LTTCOMM_SESSION_FAIL;
+		lur.ret_code = ret;
+	}
+	switch (lum->cmd) {
+	case LTTNG_UST_STREAM:
+		/*
+		 * Special-case reply to send stream info.
+		 * Use lum.u output.
+		 */
+		lur.u.stream.memory_map_size = lum->u.stream.memory_map_size;
+		shm_fd = lum->u.stream.shm_fd;
+		wait_fd = lum->u.stream.wait_fd;
+		break;
+	case LTTNG_UST_METADATA:
+	case LTTNG_UST_CHANNEL:
+		lur.u.channel.memory_map_size = lum->u.channel.memory_map_size;
+		shm_fd = lum->u.channel.shm_fd;
+		wait_fd = lum->u.channel.wait_fd;
+		break;
 	}
 	ret = send_reply(sock, &lur);
+	if (ret < 0) {
+		perror("error sending reply");
+		goto error;
+	}
 
+	if ((lum->cmd == LTTNG_UST_STREAM
+	     || lum->cmd == LTTNG_UST_CHANNEL
+	     || lum->cmd == LTTNG_UST_METADATA)
+			&& lur.ret_code == LTTCOMM_OK) {
+		/* we also need to send the file descriptors. */
+		ret = lttcomm_send_fds_unix_sock(sock,
+			&shm_fd, &shm_fd,
+			1, sizeof(int));
+		if (ret < 0) {
+			perror("send shm_fd");
+			goto error;
+		}
+		ret = lttcomm_send_fds_unix_sock(sock,
+			&wait_fd, &wait_fd,
+			1, sizeof(int));
+		if (ret < 0) {
+			perror("send wait_fd");
+			goto error;
+		}
+	}
+error:
 	ust_unlock();
 	return ret;
 }
@@ -513,7 +560,6 @@ void wait_for_sessiond(struct sock_info *sock_info)
 "mainline). LTTng-UST will use polling mode fallback.");
 			}
 			PERROR("futex");
-			sleep(5);
 		}
 	}
 	return;
@@ -524,8 +570,6 @@ quit:
 
 error:
 	ust_unlock();
-	/* Error handling: fallback on a 5 seconds sleep. */
-	sleep(5);
 	return;
 }
 
@@ -540,10 +584,25 @@ static
 void *ust_listener_thread(void *arg)
 {
 	struct sock_info *sock_info = arg;
-	int sock, ret;
+	int sock, ret, prev_connect_failed = 0, has_waited = 0;
 
 	/* Restart trying to connect to the session daemon */
 restart:
+	if (prev_connect_failed) {
+		/* Wait for sessiond availability with pipe */
+		wait_for_sessiond(sock_info);
+		if (has_waited) {
+			has_waited = 0;
+			/*
+			 * Sleep for 5 seconds before retrying after a
+			 * sequence of failure / wait / failure. This
+			 * deals with a killed or broken session daemon.
+			 */
+			sleep(5);
+		}
+		has_waited = 1;
+		prev_connect_failed = 0;
+	}
 	ust_lock();
 
 	if (lttng_ust_comm_should_quit) {
@@ -563,6 +622,7 @@ restart:
 	ret = lttcomm_connect_unix_sock(sock_info->sock_path);
 	if (ret < 0) {
 		ERR("Error connecting to %s apps socket", sock_info->name);
+		prev_connect_failed = 1;
 		/*
 		 * If we cannot find the sessiond daemon, don't delay
 		 * constructor execution.
@@ -570,9 +630,6 @@ restart:
 		ret = handle_register_done(sock_info);
 		assert(!ret);
 		ust_unlock();
-
-		/* Wait for sessiond availability with pipe */
-		wait_for_sessiond(sock_info);
 		goto restart;
 	}
 
@@ -584,7 +641,7 @@ restart:
 	 */
 	if (sock_info->root_handle == -1) {
 		ret = lttng_abi_create_root_handle();
-		if (ret) {
+		if (ret < 0) {
 			ERR("Error creating root handle");
 			ust_unlock();
 			goto quit;
@@ -595,6 +652,7 @@ restart:
 	ret = register_app_to_sessiond(sock);
 	if (ret < 0) {
 		ERR("Error registering to %s apps socket", sock_info->name);
+		prev_connect_failed = 1;
 		/*
 		 * If we cannot register to the sessiond daemon, don't
 		 * delay constructor execution.
@@ -602,7 +660,6 @@ restart:
 		ret = handle_register_done(sock_info);
 		assert(!ret);
 		ust_unlock();
-		wait_for_sessiond(sock_info);
 		goto restart;
 	}
 	ust_unlock();