Fix: Off by uint64_t in the metadata transfer

This patch also adds a couple of debug output along with this fix.

Signed-off-by: David Goulet <dgoulet@efficios.com>

diff --git a/src/bin/lttng-relayd/main.c b/src/bin/lttng-relayd/main.c
index abefba8659d7cc429aa39588186e580de084d51b..f0663d10dd85ee1673dcfe79f561cd1102bb1f86 100644 (file)
--- a/src/bin/lttng-relayd/main.c
+++ b/src/bin/lttng-relayd/main.c
@@ -1071,7 +1071,12 @@ int relay_recv_metadata(struct lttcomm_relayd_hdr *recv_hdr,
        }
 
        data_size = be64toh(recv_hdr->data_size);
-       payload_size = data_size - sizeof(uint64_t);
+       payload_size = data_size;
+       /*
+        * Add 8 bytes (uint64_t) to the data size which is the value of the
+        * stream_id and the payload size.
+        */
+       data_size +=  sizeof(uint64_t);
        if (data_buffer_size < data_size) {
                data_buffer = realloc(data_buffer, data_size);
                if (!data_buffer) {
@@ -1083,7 +1088,8 @@ int relay_recv_metadata(struct lttcomm_relayd_hdr *recv_hdr,
        }
        memset(data_buffer, 0, data_size);
        DBG2("Relay receiving metadata, waiting for %lu bytes", data_size);
-       ret = cmd->sock->ops->recvmsg(cmd->sock, data_buffer, data_size, MSG_WAITALL);
+       ret = cmd->sock->ops->recvmsg(cmd->sock, data_buffer, data_size,
+                       MSG_WAITALL);
        if (ret < 0 || ret != data_size) {
                ret = -1;
                ERR("Relay didn't receive the whole metadata");
@@ -1103,7 +1109,7 @@ int relay_recv_metadata(struct lttcomm_relayd_hdr *recv_hdr,
                ret = write(metadata_stream->fd, metadata_struct->payload,
                                payload_size);
        } while (ret < 0 && errno == EINTR);
-       if (ret < (payload_size)) {
+       if (ret < payload_size) {
                ERR("Relay error writing metadata on file");
                ret = -1;
                goto end_unlock;
@@ -1234,6 +1240,7 @@ int relay_process_data(struct relay_command *cmd, struct lttng_ht *streams_ht)
        }
        memset(data_buffer, 0, data_size);
 
+       DBG3("Receiving data of size %u for stream id %zu", data_size, stream_id);
        ret = cmd->sock->ops->recvmsg(cmd->sock, data_buffer, data_size, MSG_WAITALL);
        if (ret <= 0) {
                ret = -1;
@@ -1377,6 +1384,7 @@ void *relay_thread_worker(void *data)
 
                /* Infinite blocking call, waiting for transmission */
        restart:
+               DBG3("Relayd worker thread polling...");
                ret = lttng_poll_wait(&events, -1);
                if (ret < 0) {
                        /*

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index 4cd6972125dccba26fcfadee133b7438d91c5eeb..a57bf15987d28061bf56a994dfacc0ad882c6ecd 100644 (file)
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -63,7 +63,8 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
        if (stream->net_seq_idx != -1) {
                relayd = consumer_find_relayd(stream->net_seq_idx);
                if (relayd == NULL) {
-                       ERR("Cannot find relay for network stream\n");
+                       ERR("UST consumer mmap(), unable to find relay for index %d",
+                                       stream->net_seq_idx);
                        goto end;
                }
        }