Fix: take index seq number into account for rotation pending check

[lttng-tools.git] / src / bin / lttng-relayd / main.c

diff --git a/src/bin/lttng-relayd/main.c b/src/bin/lttng-relayd/main.c
index c84ebaac1c2c66b3d6f282aa6e1d69d161e16f23..f111b931c7792c3b3f627977bb7ed62e6999c1a4 100644 (file)
--- a/src/bin/lttng-relayd/main.c
+++ b/src/bin/lttng-relayd/main.c
@@ -1746,18 +1746,27 @@ static
 int try_rotate_stream(struct relay_stream *stream)
 {
        int ret = 0;
+       uint64_t trace_seq;
 
        /* No rotation expected. */
        if (stream->rotate_at_seq_num == -1ULL) {
                goto end;
        }
 
-       if (stream->prev_seq < stream->rotate_at_seq_num ||
-                       stream->prev_seq == -1ULL) {
-               DBG("Stream %" PRIu64 " no yet ready for rotation",
-                               stream->stream_handle);
+       trace_seq = min(stream->prev_seq, stream->prev_index_seq);
+       if (stream->prev_seq == -1ULL || stream->prev_index_seq == -1ULL ||
+                       trace_seq < stream->rotate_at_seq_num) {
+               DBG("Stream %" PRIu64 " not yet ready for rotation (rotate_at_seq_num = %" PRIu64 ", prev_seq = %" PRIu64 ", prev_index_seq = %" PRIu64 ")",
+                               stream->stream_handle,
+                               stream->rotate_at_seq_num,
+                               stream->prev_seq,
+                               stream->prev_index_seq);
                goto end;
        } else if (stream->prev_seq > stream->rotate_at_seq_num) {
+               /*
+                * prev_seq is checked here since indexes and rotation
+                * commands are serialized with respect to each other.
+                */
                DBG("Rotation after too much data has been written in tracefile "
                                "for stream %" PRIu64 ", need to truncate before "
                                "rotating", stream->stream_handle);
@@ -1767,7 +1776,20 @@ int try_rotate_stream(struct relay_stream *stream)
                        goto end;
                }
        } else {
-               /* stream->prev_seq == stream->rotate_at_seq_num */
+               if (trace_seq != stream->rotate_at_seq_num) {
+                       /*
+                        * Unexpected, protocol error/bug.
+                        * It could mean that we received a rotation position
+                        * that is in the past.
+                        */
+                       ERR("Stream %" PRIu64 " is in an inconsistent state (rotate_at_seq_num = %" PRIu64 ", prev_seq = %" PRIu64 ", prev_index_seq = %" PRIu64 ")",
+                               stream->stream_handle,
+                               stream->rotate_at_seq_num,
+                               stream->prev_seq,
+                               stream->prev_index_seq);
+                       ret = -1;
+                       goto end;
+               }
                DBG("Stream %" PRIu64 " ready for rotation",
                                stream->stream_handle);
                ret = do_rotate_stream(stream);