diff --git a/kernel/printk/printk_ringbuffer.c b/kernel/printk/printk_ringbuffer.c
index 2b7b6ddab4f7..2dc4d5a1f1ff 100644
--- a/kernel/printk/printk_ringbuffer.c
+++ b/kernel/printk/printk_ringbuffer.c
@@ -203,7 +203,7 @@
  *	prb_rec_init_wr(&r, 5);
  *
  *	// try to extend, but only if it does not exceed 32 bytes
- *	if (prb_reserve_in_last(&e, &test_rb, &r, printk_caller_id()), 32) {
+ *	if (prb_reserve_in_last(&e, &test_rb, &r, printk_caller_id(), 32)) {
  *		snprintf(&r.text_buf[r.info->text_len],
  *			 r.text_buf_size - r.info->text_len, "hello");
  *