From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Fri, 24 Feb 2012 19:26:30 +0000 (-0500)
Subject: Fix: restart consumerd and sessiond when interrupted in poll()
X-Git-Tag: v2.0.0-rc2~23
X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=a8b0b34167a4d7a46373b463d0744d75f2416bbb

Fix: restart consumerd and sessiond when interrupted in poll()

When poll() is interrupted (e.g. by a debugger attaching), it should
restart instead of exiting with an error.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: David Goulet <dgoulet@efficios.com>
---

diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index a8156cf12..93417bca0 100644
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -831,8 +831,15 @@ static void *thread_manage_kernel(void *data)
 		lttng_poll_reset(&events);
 
 		/* Poll infinite value of time */
+	restart:
 		ret = lttng_poll_wait(&events, -1);
 		if (ret < 0) {
+			/*
+			 * Restart interrupted system call.
+			 */
+			if (errno == EINTR) {
+				goto restart;
+			}
 			goto error;
 		} else if (ret == 0) {
 			/* Should not happen since timeout is infinite */
@@ -922,8 +929,15 @@ static void *thread_manage_consumer(void *data)
 	nb_fd = LTTNG_POLL_GETNB(&events);
 
 	/* Inifinite blocking call, waiting for transmission */
+restart:
 	ret = lttng_poll_wait(&events, -1);
 	if (ret < 0) {
+		/*
+		 * Restart interrupted system call.
+		 */
+		if (errno == EINTR) {
+			goto restart;
+		}
 		goto error;
 	}
 
@@ -993,8 +1007,15 @@ static void *thread_manage_consumer(void *data)
 	nb_fd = LTTNG_POLL_GETNB(&events);
 
 	/* Inifinite blocking call, waiting for transmission */
+restart_poll:
 	ret = lttng_poll_wait(&events, -1);
 	if (ret < 0) {
+		/*
+		 * Restart interrupted system call.
+		 */
+		if (errno == EINTR) {
+			goto restart_poll;
+		}
 		goto error;
 	}
 
@@ -1077,8 +1098,15 @@ static void *thread_manage_apps(void *data)
 		DBG("Apps thread polling on %d fds", nb_fd);
 
 		/* Inifinite blocking call, waiting for transmission */
+	restart:
 		ret = lttng_poll_wait(&events, -1);
 		if (ret < 0) {
+			/*
+			 * Restart interrupted system call.
+			 */
+			if (errno == EINTR) {
+				goto restart;
+			}
 			goto error;
 		}
 
@@ -1296,8 +1324,15 @@ static void *thread_registration_apps(void *data)
 		nb_fd = LTTNG_POLL_GETNB(&events);
 
 		/* Inifinite blocking call, waiting for transmission */
+	restart:
 		ret = lttng_poll_wait(&events, -1);
 		if (ret < 0) {
+			/*
+			 * Restart interrupted system call.
+			 */
+			if (errno == EINTR) {
+				goto restart;
+			}
 			goto error;
 		}
 
@@ -3594,8 +3629,15 @@ static void *thread_manage_clients(void *data)
 		nb_fd = LTTNG_POLL_GETNB(&events);
 
 		/* Inifinite blocking call, waiting for transmission */
+	restart:
 		ret = lttng_poll_wait(&events, -1);
 		if (ret < 0) {
+			/*
+			 * Restart interrupted system call.
+			 */
+			if (errno == EINTR) {
+				goto restart;
+			}
 			goto error;
 		}
 
diff --git a/src/common/consumer.c b/src/common/consumer.c
index b605591e4..ec5940105 100644
--- a/src/common/consumer.c
+++ b/src/common/consumer.c
@@ -492,8 +492,15 @@ int lttng_consumer_poll_socket(struct pollfd *consumer_sockpoll)
 {
 	int num_rdy;
 
+restart:
 	num_rdy = poll(consumer_sockpoll, 2, -1);
 	if (num_rdy == -1) {
+		/*
+		 * Restart interrupted system call.
+		 */
+		if (errno == EINTR) {
+			goto restart;
+		}
 		perror("Poll error");
 		goto exit;
 	}
@@ -896,10 +903,17 @@ void *lttng_consumer_thread_poll_fds(void *data)
 		pthread_mutex_unlock(&consumer_data.lock);
 
 		/* poll on the array of fds */
+	restart:
 		DBG("polling on %d fd", nb_fd + 1);
 		num_rdy = poll(pollfd, nb_fd + 1, consumer_poll_timeout);
 		DBG("poll num_rdy : %d", num_rdy);
 		if (num_rdy == -1) {
+			/*
+			 * Restart interrupted system call.
+			 */
+			if (errno == EINTR) {
+				goto restart;
+			}
 			perror("Poll error");
 			lttng_consumer_send_error(ctx, CONSUMERD_POLL_ERROR);
 			goto end;