+ ret = LTTNG_ERR_UNKNOWN_DOMAIN;
+ goto error;
+ }
+
+ switch (domain->type) {
+ case LTTNG_DOMAIN_KERNEL:
+ {
+ struct ltt_kernel_channel *kchan;
+
+ kchan = trace_kernel_get_channel_by_name(
+ attr->name, session->kernel_session);
+ if (kchan == NULL) {
+ /*
+ * Don't try to create a channel if the session has been started at
+ * some point in time before. The tracer does not allow it.
+ */
+ if (session->has_been_started) {
+ ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
+ goto error;
+ }
+
+ if (session->snapshot.nb_output > 0 ||
+ session->snapshot_mode) {
+ /* Enforce mmap output for snapshot sessions. */
+ attr->attr.output = LTTNG_EVENT_MMAP;
+ }
+ ret = channel_kernel_create(
+ session->kernel_session, attr, wpipe);
+ if (attr->name[0] != '\0') {
+ session->kernel_session->has_non_default_channel = 1;
+ }
+ } else {
+ ret = channel_kernel_enable(session->kernel_session, kchan);
+ }
+
+ if (ret != LTTNG_OK) {
+ goto error;
+ }
+
+ kernel_wait_quiescent();
+ break;
+ }
+ case LTTNG_DOMAIN_UST:
+ case LTTNG_DOMAIN_JUL:
+ case LTTNG_DOMAIN_LOG4J:
+ case LTTNG_DOMAIN_PYTHON:
+ {
+ struct ltt_ust_channel *uchan;
+
+ /*
+ * FIXME
+ *
+ * Current agent implementation limitations force us to allow
+ * only one channel at once in "agent" subdomains. Each
+ * subdomain has a default channel name which must be strictly
+ * adhered to.
+ */
+ if (domain->type == LTTNG_DOMAIN_JUL) {
+ if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
+ LTTNG_SYMBOL_NAME_LEN)) {
+ ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
+ goto error;
+ }
+ } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
+ if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
+ LTTNG_SYMBOL_NAME_LEN)) {
+ ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
+ goto error;
+ }
+ } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
+ if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
+ LTTNG_SYMBOL_NAME_LEN)) {
+ ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
+ goto error;
+ }
+ }
+
+ chan_ht = usess->domain_global.channels;
+
+ uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
+ if (uchan == NULL) {
+ /*
+ * Don't try to create a channel if the session has been started at
+ * some point in time before. The tracer does not allow it.
+ */
+ if (session->has_been_started) {
+ ret = LTTNG_ERR_TRACE_ALREADY_STARTED;
+ goto error;
+ }
+
+ ret = channel_ust_create(usess, attr, domain->buf_type);
+ if (attr->name[0] != '\0') {
+ usess->has_non_default_channel = 1;
+ }
+ } else {
+ ret = channel_ust_enable(usess, uchan);
+ }
+ break;
+ }
+ default:
+ ret = LTTNG_ERR_UNKNOWN_DOMAIN;
+ goto error;
+ }
+
+ if (ret == LTTNG_OK && attr->attr.output != LTTNG_EVENT_MMAP) {
+ session->has_non_mmap_channel = true;
+ }
+error:
+ rcu_read_unlock();
+end:
+ lttng_channel_destroy(attr);
+ return ret;
+}
+
+enum lttng_error_code cmd_process_attr_tracker_get_tracking_policy(
+ struct ltt_session *session,
+ enum lttng_domain_type domain,
+ enum lttng_process_attr process_attr,
+ enum lttng_tracking_policy *policy)
+{
+ enum lttng_error_code ret_code = LTTNG_OK;
+ const struct process_attr_tracker *tracker;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ if (!session->kernel_session) {
+ ret_code = LTTNG_ERR_INVALID;
+ goto end;
+ }
+ tracker = kernel_get_process_attr_tracker(
+ session->kernel_session, process_attr);
+ break;
+ case LTTNG_DOMAIN_UST:
+ if (!session->ust_session) {
+ ret_code = LTTNG_ERR_INVALID;
+ goto end;
+ }
+ tracker = trace_ust_get_process_attr_tracker(
+ session->ust_session, process_attr);
+ break;
+ default:
+ ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
+ goto end;
+ }
+ if (tracker) {
+ *policy = process_attr_tracker_get_tracking_policy(tracker);
+ } else {
+ ret_code = LTTNG_ERR_INVALID;
+ }
+end:
+ return ret_code;
+}
+
+enum lttng_error_code cmd_process_attr_tracker_set_tracking_policy(
+ struct ltt_session *session,
+ enum lttng_domain_type domain,
+ enum lttng_process_attr process_attr,
+ enum lttng_tracking_policy policy)
+{
+ enum lttng_error_code ret_code = LTTNG_OK;
+
+ switch (policy) {
+ case LTTNG_TRACKING_POLICY_INCLUDE_SET:
+ case LTTNG_TRACKING_POLICY_EXCLUDE_ALL:
+ case LTTNG_TRACKING_POLICY_INCLUDE_ALL:
+ break;
+ default:
+ ret_code = LTTNG_ERR_INVALID;
+ goto end;
+ }
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ if (!session->kernel_session) {
+ ret_code = LTTNG_ERR_INVALID;
+ goto end;
+ }
+ ret_code = kernel_process_attr_tracker_set_tracking_policy(
+ session->kernel_session, process_attr, policy);
+ break;
+ case LTTNG_DOMAIN_UST:
+ if (!session->ust_session) {
+ ret_code = LTTNG_ERR_INVALID;
+ goto end;
+ }
+ ret_code = trace_ust_process_attr_tracker_set_tracking_policy(
+ session->ust_session, process_attr, policy);
+ break;
+ default:
+ ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
+ break;
+ }
+end:
+ return ret_code;
+}
+
+enum lttng_error_code cmd_process_attr_tracker_inclusion_set_add_value(
+ struct ltt_session *session,
+ enum lttng_domain_type domain,
+ enum lttng_process_attr process_attr,
+ const struct process_attr_value *value)
+{
+ enum lttng_error_code ret_code = LTTNG_OK;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ if (!session->kernel_session) {
+ ret_code = LTTNG_ERR_INVALID;
+ goto end;
+ }
+ ret_code = kernel_process_attr_tracker_inclusion_set_add_value(
+ session->kernel_session, process_attr, value);
+ break;
+ case LTTNG_DOMAIN_UST:
+ if (!session->ust_session) {
+ ret_code = LTTNG_ERR_INVALID;
+ goto end;
+ }
+ ret_code = trace_ust_process_attr_tracker_inclusion_set_add_value(
+ session->ust_session, process_attr, value);
+ break;
+ default:
+ ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
+ break;
+ }
+end:
+ return ret_code;
+}
+
+enum lttng_error_code cmd_process_attr_tracker_inclusion_set_remove_value(
+ struct ltt_session *session,
+ enum lttng_domain_type domain,
+ enum lttng_process_attr process_attr,
+ const struct process_attr_value *value)
+{
+ enum lttng_error_code ret_code = LTTNG_OK;
+
+ switch (domain) {
+ case LTTNG_DOMAIN_KERNEL:
+ if (!session->kernel_session) {
+ ret_code = LTTNG_ERR_INVALID;
+ goto end;
+ }
+ ret_code = kernel_process_attr_tracker_inclusion_set_remove_value(
+ session->kernel_session, process_attr, value);
+ break;
+ case LTTNG_DOMAIN_UST:
+ if (!session->ust_session) {
+ ret_code = LTTNG_ERR_INVALID;
+ goto end;
+ }
+ ret_code = trace_ust_process_attr_tracker_inclusion_set_remove_value(
+ session->ust_session, process_attr, value);
+ break;
+ default:
+ ret_code = LTTNG_ERR_UNSUPPORTED_DOMAIN;
+ break;