X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fkernel.c;h=47833dc8bd9b7fc011153ed3cfa4109134644504;hb=2b5f1a27dceffd016755c0a62c9686c3b61f6aaa;hp=f8dcd718fc3cb73ce14d3ce5c5dc84a4a72800e4;hpb=38cd0ad9f99bedeffd9fa659943f1fe050b7a16a;p=lttng-tools.git

diff --git a/src/bin/lttng-sessiond/kernel.c b/src/bin/lttng-sessiond/kernel.c
index f8dcd718f..47833dc8b 100644
--- a/src/bin/lttng-sessiond/kernel.c
+++ b/src/bin/lttng-sessiond/kernel.c
@@ -34,6 +34,12 @@
 #include "kern-modules.h"
 #include "utils.h"
 
+/*
+ * Key used to reference a channel between the sessiond and the consumer. This
+ * is only read and updated with the session_list lock held.
+ */
+static uint64_t next_kernel_channel_key;
+
 /*
  * Add context on a kernel channel.
  *
@@ -169,8 +175,10 @@ int kernel_create_channel(struct ltt_kernel_session *session,
 	cds_list_add(&lkc->list, &session->channel_list.head);
 	session->channel_count++;
 	lkc->session = session;
+	lkc->key = ++next_kernel_channel_key;
 
-	DBG("Kernel channel %s created (fd: %d)", lkc->channel->name, lkc->fd);
+	DBG("Kernel channel %s created (fd: %d, key: %" PRIu64 ")",
+			lkc->channel->name, lkc->fd, lkc->key);
 
 	return 0;
 
@@ -291,7 +299,8 @@ int kernel_disable_channel(struct ltt_kernel_channel *chan)
 	}
 
 	chan->enabled = 0;
-	DBG("Kernel channel %s disabled (fd: %d)", chan->channel->name, chan->fd);
+	DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64 ")",
+			chan->channel->name, chan->fd, chan->key);
 
 	return 0;
 
@@ -315,7 +324,8 @@ int kernel_enable_channel(struct ltt_kernel_channel *chan)
 	}
 
 	chan->enabled = 1;
-	DBG("Kernel channel %s enabled (fd: %d)", chan->channel->name, chan->fd);
+	DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64 ")",
+			chan->channel->name, chan->fd, chan->key);
 
 	return 0;
 
@@ -525,6 +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) {
@@ -1042,7 +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) {
@@ -1139,7 +1150,7 @@ enum lttng_error_code kernel_clear_session(struct ltt_session *session)
 	assert(ksess);
 	assert(ksess->consumer);
 
-	DBG("Cleat kernel session %s (session %" PRIu64 ")",
+	DBG("Clear kernel session %s (session %" PRIu64 ")",
 			session->name, session->id);
 
 	rcu_read_lock();
@@ -1163,6 +1174,15 @@ enum lttng_error_code kernel_clear_session(struct ltt_session *session)
 			}
 		}
 
+		if (!ksess->metadata) {
+			/*
+			 * Nothing to do for the metadata.
+			 * This is a snpashot session.
+			 * The metadata is genererated on the fly.
+			 */
+			continue;
+		}
+
 		/*
 		 * Clear the metadata channel.
 		 * Metadata channel is not cleared per se but we still need to