Fix: relayd metadata size

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

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index 1cd39ef34b7e957bf9cfa95ac93e7fb40374fb9c..7ce03ad87dde9b442015f3dc5af9b05697e2d8a5 100644 (file)
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -56,10 +56,15 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
        uint64_t metadata_id;
        struct consumer_relayd_sock_pair *relayd = NULL;
 
+       /* RCU lock for the relayd pointer */
+       rcu_read_lock();
+
        /* Flag that the current stream if set for network streaming. */
        if (stream->net_seq_idx != -1) {
                relayd = consumer_find_relayd(stream->net_seq_idx);
                if (relayd == NULL) {
+                       ERR("UST consumer mmap(), unable to find relay for index %d",
+                                       stream->net_seq_idx);
                        goto end;
                }
        }
@@ -76,12 +81,15 @@ ssize_t lttng_ustconsumer_on_read_subbuffer_mmap(
 
        /* Handle stream on the relayd if the output is on the network */
        if (relayd) {
+               unsigned long netlen = len;
+
                if (stream->metadata_flag) {
                        /* Only lock if metadata since we use the control socket. */
                        pthread_mutex_lock(&relayd->ctrl_sock_mutex);
+                       netlen += sizeof(stream->relayd_stream_id);
                }
 
-               ret = consumer_handle_stream_before_relayd(stream, len);
+               ret = consumer_handle_stream_before_relayd(stream, netlen);
                if (ret >= 0) {
                        outfd = ret;
 
@@ -139,6 +147,7 @@ end:
        if (relayd && stream->metadata_flag) {
                pthread_mutex_unlock(&relayd->ctrl_sock_mutex);
        }
+       rcu_read_unlock();
        return written;
 }
 
@@ -210,6 +219,9 @@ int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data *ctx,
                return -ENOENT;
        }
 
+       /* relayd need RCU read-side lock */
+       rcu_read_lock();
+
        switch (msg.cmd_type) {
        case LTTNG_CONSUMER_ADD_RELAYD_SOCKET:
        {
@@ -433,6 +445,7 @@ end:
                ret = write(ctx->consumer_poll_pipe[1], "", 1);
        } while (ret < 0 && errno == EINTR);
 end_nosignal:
+       rcu_read_unlock();
        return 0;
 }