From: Francis Deslauriers <francis.deslauriers@efficios.com>
Date: Fri, 2 Mar 2018 15:41:34 +0000 (-0500)
Subject: Use free running metadata channel key between sessiond and kernel consumer
X-Git-Tag: v2.11.0-rc1~368
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=d40f035921a2d3be652d31bdcc250db521f96209;p=lttng-tools.git

Use free running metadata channel key between sessiond and kernel consumer

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/src/bin/lttng-sessiond/kernel-consumer.c b/src/bin/lttng-sessiond/kernel-consumer.c
index 10011f4cd..160c19f59 100644
--- a/src/bin/lttng-sessiond/kernel-consumer.c
+++ b/src/bin/lttng-sessiond/kernel-consumer.c
@@ -218,7 +218,7 @@ int kernel_consumer_add_metadata(struct consumer_socket *sock,
 	/* Prep channel message structure */
 	consumer_init_channel_comm_msg(&lkm,
 			LTTNG_CONSUMER_ADD_CHANNEL,
-			session->metadata->fd,
+			session->metadata->key,
 			session->id,
 			pathname,
 			session->uid,
@@ -243,7 +243,7 @@ int kernel_consumer_add_metadata(struct consumer_socket *sock,
 	/* Prep stream message structure */
 	consumer_init_stream_comm_msg(&lkm,
 			LTTNG_CONSUMER_ADD_STREAM,
-			session->metadata->fd,
+			session->metadata->key,
 			session->metadata_stream_fd,
 			0); /* CPU: 0 for metadata. */
 
@@ -497,11 +497,11 @@ int kernel_consumer_destroy_metadata(struct consumer_socket *socket,
 	assert(metadata);
 	assert(socket);
 
-	DBG("Sending kernel consumer destroy channel key %d", metadata->fd);
+	DBG("Sending kernel consumer destroy channel key %" PRIu64, metadata->key);
 
 	memset(&msg, 0, sizeof(msg));
 	msg.cmd_type = LTTNG_CONSUMER_DESTROY_CHANNEL;
-	msg.u.destroy_channel.key = metadata->fd;
+	msg.u.destroy_channel.key = metadata->key;
 
 	pthread_mutex_lock(socket->lock);
 	health_code_update();
diff --git a/src/bin/lttng-sessiond/kernel.c b/src/bin/lttng-sessiond/kernel.c
index 158a12a36..e5f068a0c 100644
--- a/src/bin/lttng-sessiond/kernel.c
+++ b/src/bin/lttng-sessiond/kernel.c
@@ -535,6 +535,7 @@ int kernel_open_metadata(struct ltt_kernel_session *session)
 	}
 
 	lkm->fd = ret;
+	lkm->key = ++next_kernel_channel_key;
 	/* Prevent fd duplication after execlp() */
 	ret = fcntl(lkm->fd, F_SETFD, FD_CLOEXEC);
 	if (ret < 0) {
@@ -1052,7 +1053,7 @@ int kernel_snapshot_record(struct ltt_kernel_session *ksess,
 		}
 
 		/* Snapshot metadata, */
-		ret = consumer_snapshot_channel(socket, ksess->metadata->fd, output,
+		ret = consumer_snapshot_channel(socket, ksess->metadata->key, output,
 				1, ksess->uid, ksess->gid,
 				DEFAULT_KERNEL_TRACE_DIR, wait, 0);
 		if (ret < 0) {
diff --git a/src/bin/lttng-sessiond/trace-kernel.h b/src/bin/lttng-sessiond/trace-kernel.h
index 9c52cee09..3210d4b33 100644
--- a/src/bin/lttng-sessiond/trace-kernel.h
+++ b/src/bin/lttng-sessiond/trace-kernel.h
@@ -81,6 +81,7 @@ struct ltt_kernel_channel {
 /* Metadata */
 struct ltt_kernel_metadata {
 	int fd;
+	uint64_t key; /* Key to reference this channel with the consumer. */
 	struct lttng_channel *conf;
 };