From: Julien Desfossez <jdesfossez@efficios.com>
Date: Mon, 11 Dec 2017 21:13:19 +0000 (-0500)
Subject: Cleanup: keep the number of pipes used by poll in a variable
X-Git-Tag: v2.11.0-rc1~359
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=261de6373c70dcd52421642db5486747e9c10bae;p=lttng-tools.git

Cleanup: keep the number of pipes used by poll in a variable

The "2" hardcoded at multiple places in the consumer is prone to error
when adding new FDs. Keep it all in one place to make it easier next
time we modify it.

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/src/common/consumer/consumer.c b/src/common/consumer/consumer.c
index 820427aa9..6b920b6b1 100644
--- a/src/common/consumer/consumer.c
+++ b/src/common/consumer/consumer.c
@@ -2457,7 +2457,7 @@ void *consumer_thread_data_poll(void *data)
 	/* local view of the streams */
 	struct lttng_consumer_stream **local_stream = NULL, *new_stream = NULL;
 	/* local view of consumer_data.fds_count */
-	int nb_fd = 0;
+	int nb_fd = 0, nb_pipes_fd;
 	/* Number of FDs with CONSUMER_ENDPOINT_INACTIVE but still open. */
 	int nb_inactive_fd = 0;
 	struct lttng_consumer_local_data *ctx = data;
@@ -2498,17 +2498,19 @@ void *consumer_thread_data_poll(void *data)
 			local_stream = NULL;
 
 			/*
-			 * Allocate for all fds +1 for the consumer_data_pipe and +1 for
-			 * wake up pipe.
+			 * Allocate for all fds + 2:
+			 *   +1 for the consumer_data_pipe
+			 *   +1 for wake up pipe
 			 */
-			pollfd = zmalloc((consumer_data.stream_count + 2) * sizeof(struct pollfd));
+			nb_pipes_fd = 2;
+			pollfd = zmalloc((consumer_data.stream_count + nb_pipes_fd) * sizeof(struct pollfd));
 			if (pollfd == NULL) {
 				PERROR("pollfd malloc");
 				pthread_mutex_unlock(&consumer_data.lock);
 				goto end;
 			}
 
-			local_stream = zmalloc((consumer_data.stream_count + 2) *
+			local_stream = zmalloc((consumer_data.stream_count + nb_pipes_fd) *
 					sizeof(struct lttng_consumer_stream *));
 			if (local_stream == NULL) {
 				PERROR("local_stream malloc");
@@ -2536,12 +2538,12 @@ void *consumer_thread_data_poll(void *data)
 		}
 		/* poll on the array of fds */
 	restart:
-		DBG("polling on %d fd", nb_fd + 2);
+		DBG("polling on %d fd", nb_fd + nb_pipes_fd);
 		if (testpoint(consumerd_thread_data_poll)) {
 			goto end;
 		}
 		health_poll_entry();
-		num_rdy = poll(pollfd, nb_fd + 2, -1);
+		num_rdy = poll(pollfd, nb_fd + nb_pipes_fd, -1);
 		health_poll_exit();
 		DBG("poll num_rdy : %d", num_rdy);
 		if (num_rdy == -1) {