Fix: mark consumer channels as logically deleted during deletion

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

diff --git a/src/common/consumer/consumer.c b/src/common/consumer/consumer.c
index 914eda8c5a1386f3650d6b47cc499e64986267a5..82fe0168f2c85b11cac63390ddd427a763dc4149 100644 (file)
--- a/src/common/consumer/consumer.c
+++ b/src/common/consumer/consumer.c
@@ -411,7 +411,8 @@ void consumer_del_channel(struct lttng_consumer_channel *channel)
                rcu_read_unlock();
        }
 
-        call_rcu(&channel->node.head, free_channel_rcu);
+       channel->is_deleted = true;
+       call_rcu(&channel->node.head, free_channel_rcu);
 end:
        pthread_mutex_unlock(&channel->lock);
        pthread_mutex_unlock(&consumer_data.lock);
@@ -1021,6 +1022,16 @@ int lttng_consumer_channel_set_trace_chunk(
        unsigned long channel_hash;
 
        pthread_mutex_lock(&channel->lock);
+       if (channel->is_deleted) {
+               /*
+                * The channel has been logically deleted and should no longer
+                * be used. It has released its reference to its current trace
+                * chunk and should not acquire a new one.
+                *
+                * Return success as there is nothing for the caller to do.
+                */
+               goto end;
+       }
        /*
         * A stream can transition to a state where it and its channel
         * no longer belong to a trace chunk. For instance, this happens when
@@ -1727,9 +1738,8 @@ ssize_t lttng_consumer_on_read_subbuffer_mmap(
 
        /* RCU lock for the relayd pointer */
        rcu_read_lock();
-
        assert(stream->net_seq_idx != (uint64_t) -1ULL ||
-                       stream->chan->trace_chunk);
+                       stream->trace_chunk);
 
        /* Flag that the current stream if set for network streaming. */
        if (stream->net_seq_idx != (uint64_t) -1ULL) {