#include <sys/types.h>
#include <unistd.h>
#include <urcu/compiler.h>
-#include <lttng/ust-error.h>
#include <signal.h>
#include <common/common.h>
#include "health-sessiond.h"
#include "ust-app.h"
#include "ust-consumer.h"
-#include "ust-ctl.h"
+#include "lttng-ust-ctl.h"
+#include "lttng-ust-error.h"
#include "utils.h"
#include "session.h"
#include "lttng-sessiond.h"
* nullified. The session lock MUST be held unless the application is
* in the destroy path.
*
+ * Do not hold the registry lock while communicating with the consumerd, because
+ * doing so causes inter-process deadlocks between consumerd and sessiond with
+ * the metadata request notification.
+ *
* Return 0 on success else a negative value.
*/
static int close_metadata(struct ust_registry_session *registry,
{
int ret;
struct consumer_socket *socket;
+ uint64_t metadata_key;
+ bool registry_was_already_closed;
assert(registry);
assert(consumer);
rcu_read_lock();
pthread_mutex_lock(®istry->lock);
+ metadata_key = registry->metadata_key;
+ registry_was_already_closed = registry->metadata_closed;
+ if (metadata_key != 0) {
+ /*
+ * Metadata closed. Even on error this means that the consumer
+ * is not responding or not found so either way a second close
+ * should NOT be emit for this registry.
+ */
+ registry->metadata_closed = 1;
+ }
+ pthread_mutex_unlock(®istry->lock);
- if (!registry->metadata_key || registry->metadata_closed) {
+ if (metadata_key == 0 || registry_was_already_closed) {
ret = 0;
goto end;
}
consumer);
if (!socket) {
ret = -1;
- goto error;
+ goto end;
}
- ret = consumer_close_metadata(socket, registry->metadata_key);
+ ret = consumer_close_metadata(socket, metadata_key);
if (ret < 0) {
- goto error;
+ goto end;
}
-error:
- /*
- * Metadata closed. Even on error this means that the consumer is not
- * responding or not found so either way a second close should NOT be emit
- * for this registry.
- */
- registry->metadata_closed = 1;
end:
- pthread_mutex_unlock(®istry->lock);
rcu_read_unlock();
return ret;
}
if (ret < 0) {
ERR("Error creating UST channel \"%s\" on the consumer daemon",
ua_chan->name);
- goto error;
+ goto error_remove_from_registry;
}
ret = send_channel_pid_to_ust(app, ua_sess, ua_chan);
if (ret != -ENOTCONN) {
ERR("Error sending channel to application");
}
- goto error;
+ goto error_remove_from_registry;
}
session = session_find_by_id(ua_sess->tracing_id);
if (cmd_ret != LTTNG_OK) {
ret = - (int) cmd_ret;
ERR("Failed to add channel to notification thread");
- goto error;
+ goto error_remove_from_registry;
}
+error_remove_from_registry:
+ if (ret) {
+ ust_registry_channel_del_free(registry, ua_chan->key, false);
+ }
error:
rcu_read_unlock();
return ret;