+static
+bool lttng_kernel_event_id_available(struct lttng_event_enabler_common *event_enabler)
+{
+ struct lttng_kernel_abi_event *event_param = &event_enabler->event_param;
+ enum lttng_kernel_abi_instrumentation itype = event_param->instrumentation;
+
+ switch (event_enabler->enabler_type) {
+ case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
+ {
+ struct lttng_event_recorder_enabler *event_recorder_enabler =
+ container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
+ struct lttng_kernel_channel_buffer *chan = event_recorder_enabler->chan;
+
+ switch (itype) {
+ case LTTNG_KERNEL_ABI_TRACEPOINT:
+ lttng_fallthrough;
+ case LTTNG_KERNEL_ABI_KPROBE:
+ lttng_fallthrough;
+ case LTTNG_KERNEL_ABI_SYSCALL:
+ lttng_fallthrough;
+ case LTTNG_KERNEL_ABI_UPROBE:
+ if (chan->priv->free_event_id == -1U)
+ return false;
+ return true;
+ case LTTNG_KERNEL_ABI_KRETPROBE:
+ /* kretprobes require 2 event IDs. */
+ if (chan->priv->free_event_id >= -2U)
+ return false;
+ return true;
+ default:
+ WARN_ON_ONCE(1);
+ return false;
+ }
+ }
+ case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
+ return true;
+ default:
+ WARN_ON_ONCE(1);
+ return false;
+ }
+}
+