Fix: kconsumer: missing wait for metadata thread in do_sync_metadata

[lttng-tools.git] / src / common / kernel-consumer / kernel-consumer.c

diff --git a/src/common/kernel-consumer/kernel-consumer.c b/src/common/kernel-consumer/kernel-consumer.c
index dd5cf1761a4992c9e7384d48675038c5438ece0e..eeec3a65e7d877291a82ba9d63bf2fb6dc8f30a3 100644 (file)
--- a/src/common/kernel-consumer/kernel-consumer.c
+++ b/src/common/kernel-consumer/kernel-consumer.c
@@ -1348,36 +1348,38 @@ end:
  * metadata thread can consumer them.
  *
  * Metadata stream lock MUST be acquired.
- *
- * Return 0 if new metadatda is available, EAGAIN if the metadata stream
- * is empty or a negative value on error.
  */
-int lttng_kconsumer_sync_metadata(struct lttng_consumer_stream *metadata)
+enum sync_metadata_status lttng_kconsumer_sync_metadata(
+               struct lttng_consumer_stream *metadata)
 {
        int ret;
+       enum sync_metadata_status status;
 
        assert(metadata);
 
        ret = kernctl_buffer_flush(metadata->wait_fd);
        if (ret < 0) {
                ERR("Failed to flush kernel stream");
+               status = SYNC_METADATA_STATUS_ERROR;
                goto end;
        }
 
        ret = kernctl_snapshot(metadata->wait_fd);
        if (ret < 0) {
-               if (ret != -EAGAIN) {
+               if (errno == EAGAIN) {
+                       /* No new metadata, exit. */
+                       DBG("Sync metadata, no new kernel metadata");
+                       status = SYNC_METADATA_STATUS_NO_DATA;
+               } else {
                        ERR("Sync metadata, taking kernel snapshot failed.");
-                       goto end;
+                       status = SYNC_METADATA_STATUS_ERROR;
                }
-               DBG("Sync metadata, no new kernel metadata");
-               /* No new metadata, exit. */
-               ret = ENODATA;
-               goto end;
+       } else {
+               status = SYNC_METADATA_STATUS_NEW_DATA;
        }
 
 end:
-       return ret;
+       return status;
 }
 
 static