Fix: add missing rcu read side lock/unlock

[lttng-tools.git] / src / bin / lttng-sessiond / consumer.c

diff --git a/src/bin/lttng-sessiond/consumer.c b/src/bin/lttng-sessiond/consumer.c
index 26ff56effe8f57715822badae8d8df2ade6c092e..344c6627dbbe507c01ba483c7ba46c8f2577b57c 100644 (file)
--- a/src/bin/lttng-sessiond/consumer.c
+++ b/src/bin/lttng-sessiond/consumer.c
@@ -45,7 +45,11 @@ int consumer_recv_status_reply(struct consumer_socket *sock)
        assert(sock);
 
        ret = lttcomm_recv_unix_sock(sock->fd, &reply, sizeof(reply));
-       if (ret < 0) {
+       if (ret <= 0) {
+               if (ret == 0) {
+                       /* Orderly shutdown. Don't return 0 which means success. */
+                       ret = -1;
+               }
                /* The above call will print a PERROR on error. */
                DBG("Fail to receive status reply on sock %d", sock->fd);
                goto end;
@@ -372,10 +376,12 @@ struct consumer_output *consumer_copy_output(struct consumer_output *obj)
        /* Putting back the HT pointer and start copying socket(s). */
        output->socks = tmp_ht_ptr;
 
+       rcu_read_lock();
        cds_lfht_for_each_entry(obj->socks->ht, &iter.iter, socket, node.node) {
                /* Create new socket object. */
                copy_sock = consumer_allocate_socket(socket->fd);
                if (copy_sock == NULL) {
+                       rcu_read_unlock();
                        goto malloc_error;
                }
 
@@ -383,6 +389,7 @@ struct consumer_output *consumer_copy_output(struct consumer_output *obj)
                copy_sock->lock = socket->lock;
                consumer_add_socket(copy_sock, output);
        }
+       rcu_read_unlock();
 
 error:
        return output;
@@ -789,6 +796,7 @@ int consumer_is_data_pending(unsigned int id,
        DBG3("Consumer data pending for id %u", id);
 
        /* Send command for each consumer */
+       rcu_read_lock();
        cds_lfht_for_each_entry(consumer->socks->ht, &iter.iter, socket,
                        node.node) {
                /* Code flow error */
@@ -801,7 +809,7 @@ int consumer_is_data_pending(unsigned int id,
                        /* The above call will print a PERROR on error. */
                        DBG("Error on consumer is data pending on sock %d", socket->fd);
                        pthread_mutex_unlock(socket->lock);
-                       goto error;
+                       goto error_unlock;
                }
 
                /*
@@ -810,11 +818,15 @@ int consumer_is_data_pending(unsigned int id,
                 */
 
                ret = lttcomm_recv_unix_sock(socket->fd, &ret_code, sizeof(ret_code));
-               if (ret < 0) {
+               if (ret <= 0) {
+                       if (ret == 0) {
+                               /* Orderly shutdown. Don't return 0 which means success. */
+                               ret = -1;
+                       }
                        /* The above call will print a PERROR on error. */
                        DBG("Error on recv consumer is data pending on sock %d", socket->fd);
                        pthread_mutex_unlock(socket->lock);
-                       goto error;
+                       goto error_unlock;
                }
 
                pthread_mutex_unlock(socket->lock);
@@ -823,11 +835,13 @@ int consumer_is_data_pending(unsigned int id,
                        break;
                }
        }
+       rcu_read_unlock();
 
        DBG("Consumer data is %s pending for session id %u",
                        ret_code == 1 ? "" : "NOT", id);
        return ret_code;
 
-error:
+error_unlock:
+       rcu_read_unlock();
        return -1;
 }