Fix: relayd: missing session unlock on error path

[lttng-tools.git] / src / bin / lttng-relayd / viewer-stream.cpp

diff --git a/src/bin/lttng-relayd/viewer-stream.cpp b/src/bin/lttng-relayd/viewer-stream.cpp
index 7a66fde5bd6b8bf54d540a8aa0762e47ee9017bd..69671bd7af4552ae6eb1803654692265a1c30cd3 100644 (file)
--- a/src/bin/lttng-relayd/viewer-stream.cpp
+++ b/src/bin/lttng-relayd/viewer-stream.cpp
@@ -15,13 +15,31 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
+#include <algorithm>
 
 #include "lttng-relayd.h"
 #include "viewer-stream.h"
 
-static void viewer_stream_destroy(struct relay_viewer_stream *vstream)
+static void viewer_stream_release_composite_objects(struct relay_viewer_stream *vstream)
 {
+       if (vstream->stream_file.handle) {
+               fs_handle_close(vstream->stream_file.handle);
+               vstream->stream_file.handle = NULL;
+       }
+       if (vstream->index_file) {
+               lttng_index_file_put(vstream->index_file);
+               vstream->index_file = NULL;
+       }
+       if (vstream->stream) {
+               stream_put(vstream->stream);
+               vstream->stream = NULL;
+       }
        lttng_trace_chunk_put(vstream->stream_file.trace_chunk);
+       vstream->stream_file.trace_chunk = NULL;
+}
+
+static void viewer_stream_destroy(struct relay_viewer_stream *vstream)
+{
        free(vstream->path_name);
        free(vstream->channel_name);
        free(vstream);
@@ -197,6 +215,8 @@ struct relay_viewer_stream *viewer_stream_create(struct relay_stream *stream,
 
 error:
        if (vstream) {
+               /* Not using `put` since vstream is assumed to be published. */
+               viewer_stream_release_composite_objects(vstream);
                viewer_stream_destroy(vstream);
        }
        return NULL;
@@ -220,23 +240,8 @@ static void viewer_stream_release(struct urcu_ref *ref)
        if (vstream->stream->is_metadata) {
                rcu_assign_pointer(vstream->stream->trace->viewer_metadata_stream, NULL);
        }
-
        viewer_stream_unpublish(vstream);
-
-       if (vstream->stream_file.handle) {
-               fs_handle_close(vstream->stream_file.handle);
-               vstream->stream_file.handle = NULL;
-       }
-       if (vstream->index_file) {
-               lttng_index_file_put(vstream->index_file);
-               vstream->index_file = NULL;
-       }
-       if (vstream->stream) {
-               stream_put(vstream->stream);
-               vstream->stream = NULL;
-       }
-       lttng_trace_chunk_put(vstream->stream_file.trace_chunk);
-       vstream->stream_file.trace_chunk = NULL;
+       viewer_stream_release_composite_objects(vstream);
        call_rcu(&vstream->rcu_node, viewer_stream_destroy_rcu);
 }
 
@@ -302,7 +307,15 @@ void viewer_stream_sync_tracefile_array_tail(struct relay_viewer_stream *vstream
        if (seq_tail == -1ULL) {
                seq_tail = 0;
        }
-       vstream->index_sent_seqcount = seq_tail;
+
+       /*
+        * Move the index sent seqcount forward if it was lagging behind
+        * the new tail of the tracefile array. If the current
+        * index_sent_seqcount is already further than the tracefile
+        * array tail position, keep its current position.
+        */
+       vstream->index_sent_seqcount =
+                       std::max(seq_tail, vstream->index_sent_seqcount);
 }
 
 /*