X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fust-consumer%2Fust-consumer.c;h=41317fe657d57cd4d5b5873c03fc2e3e77793118;hp=f8706d0ba88528e3dbf1e698de96eec9c4d5073d;hb=5da88b0f58d7f838068037ea449ddfb25d3e85ad;hpb=16aa001d9a342adc6b913f854c0cee7a896a7e03

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index f8706d0ba..41317fe65 100644
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -2039,8 +2039,7 @@ end_rotate_channel_nosignal:
 				*msg.u.create_trace_chunk.override_name ?
 					msg.u.create_trace_chunk.override_name :
 					NULL;
-		LTTNG_OPTIONAL(struct lttng_directory_handle) chunk_directory_handle =
-				LTTNG_OPTIONAL_INIT;
+		struct lttng_directory_handle *chunk_directory_handle = NULL;
 
 		/*
 		 * The session daemon will only provide a chunk directory file
@@ -2057,25 +2056,26 @@ end_rotate_channel_nosignal:
 				goto end_nosignal;
 			}
 
+			/*
+			 * Receive trace chunk domain dirfd.
+			 */
 			ret = lttcomm_recv_fds_unix_sock(sock, &chunk_dirfd, 1);
 			if (ret != sizeof(chunk_dirfd)) {
-				ERR("Failed to receive trace chunk directory file descriptor");
+				ERR("Failed to receive trace chunk domain directory file descriptor");
 				goto error_fatal;
 			}
 
-			DBG("Received trace chunk directory fd (%d)",
+			DBG("Received trace chunk domain directory fd (%d)",
 					chunk_dirfd);
-			ret = lttng_directory_handle_init_from_dirfd(
-					&chunk_directory_handle.value,
+			chunk_directory_handle = lttng_directory_handle_create_from_dirfd(
 					chunk_dirfd);
-			if (ret) {
-				ERR("Failed to initialize chunk directory handle from directory file descriptor");
+			if (!chunk_directory_handle) {
+				ERR("Failed to initialize chunk domain directory handle from directory file descriptor");
 				if (close(chunk_dirfd)) {
 					PERROR("Failed to close chunk directory file descriptor");
 				}
 				goto error_fatal;
 			}
-			chunk_directory_handle.is_set = true;
 		}
 
 		ret_code = lttng_consumer_create_trace_chunk(
@@ -2088,14 +2088,8 @@ end_rotate_channel_nosignal:
 				msg.u.create_trace_chunk.credentials.is_set ?
 						&credentials :
 						NULL,
-				chunk_directory_handle.is_set ?
-						&chunk_directory_handle.value :
-						NULL);
-
-		if (chunk_directory_handle.is_set) {
-			lttng_directory_handle_fini(
-					&chunk_directory_handle.value);
-		}
+				chunk_directory_handle);
+		lttng_directory_handle_put(chunk_directory_handle);
 		goto end_msg_sessiond;
 	}
 	case LTTNG_CONSUMER_CLOSE_TRACE_CHUNK:
@@ -2170,7 +2164,6 @@ end_msg_sessiond:
 
 end_channel_error:
 	if (channel) {
-		pthread_mutex_unlock(&channel->lock);
 		/*
 		 * Free channel here since no one has a reference to it. We don't
 		 * free after that because a stream can store this pointer.
@@ -2583,37 +2576,59 @@ end:
  * interacting with sessiond, else we cause a deadlock with live
  * awaiting on metadata to be pushed out.
  *
+ * The RCU read side lock must be held by the caller.
+ *
  * Return 0 if new metadatda is available, EAGAIN if the metadata stream
  * is empty or a negative value on error.
  */
 int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data *ctx,
-		struct lttng_consumer_stream *metadata)
+		struct lttng_consumer_stream *metadata_stream)
 {
 	int ret;
 	int retry = 0;
+	struct lttng_consumer_channel *metadata_channel;
 
 	assert(ctx);
-	assert(metadata);
+	assert(metadata_stream);
 
-	pthread_mutex_unlock(&metadata->lock);
+	metadata_channel = metadata_stream->chan;
+	pthread_mutex_unlock(&metadata_stream->lock);
 	/*
 	 * Request metadata from the sessiond, but don't wait for the flush
 	 * because we locked the metadata thread.
 	 */
-	ret = lttng_ustconsumer_request_metadata(ctx, metadata->chan, 0, 0);
-	pthread_mutex_lock(&metadata->lock);
+	ret = lttng_ustconsumer_request_metadata(ctx, metadata_channel, 0, 0);
+	pthread_mutex_lock(&metadata_stream->lock);
 	if (ret < 0) {
 		goto end;
 	}
 
-	ret = commit_one_metadata_packet(metadata);
+	/*
+	 * The metadata stream and channel can be deleted while the
+	 * metadata stream lock was released. The streamed is checked
+	 * for deletion before we use it further.
+	 *
+	 * Note that it is safe to access a logically-deleted stream since its
+	 * existence is still guaranteed by the RCU read side lock. However,
+	 * it should no longer be used. The close/deletion of the metadata
+	 * channel and stream already guarantees that all metadata has been
+	 * consumed. Therefore, there is nothing left to do in this function.
+	 */
+	if (consumer_stream_is_deleted(metadata_stream)) {
+		DBG("Metadata stream %" PRIu64 " was deleted during the metadata synchronization",
+				metadata_stream->key);
+		ret = 0;
+		goto end;
+	}
+
+	ret = commit_one_metadata_packet(metadata_stream);
 	if (ret <= 0) {
 		goto end;
 	} else if (ret > 0) {
 		retry = 1;
 	}
 
-	ret = ustctl_snapshot(metadata->ustream);
+	ret = ustctl_snapshot(metadata_stream->ustream);
 	if (ret < 0) {
 		if (errno != EAGAIN) {
 			ERR("Sync metadata, taking UST snapshot");