diff --git a/proxy/http2/Http2ClientSession.cc b/proxy/http2/Http2ClientSession.cc
index 637cece6fb1..009842f31c2 100644
--- a/proxy/http2/Http2ClientSession.cc
+++ b/proxy/http2/Http2ClientSession.cc
@@ -437,7 +437,7 @@ Http2ClientSession::state_start_frame_read(int event, void *edata)
 
   STATE_ENTER(&Http2ClientSession::state_start_frame_read, event);
   ink_assert(event == VC_EVENT_READ_COMPLETE || event == VC_EVENT_READ_READY);
-  return state_process_frame_read(event, vio, false);
+  return do_process_frame_read(event, vio, false);
 }
 
 int
@@ -513,7 +513,7 @@ Http2ClientSession::state_complete_frame_read(int event, void *edata)
   }
   Http2SsnDebug("completed frame read, %" PRId64 " bytes available", this->_read_buffer_reader->read_avail());
 
-  return state_process_frame_read(event, vio, true);
+  return do_process_frame_read(event, vio, true);
 }
 
 int
@@ -539,7 +539,7 @@ Http2ClientSession::do_complete_frame_read()
 }
 
 int
-Http2ClientSession::state_process_frame_read(int event, VIO *vio, bool inside_frame)
+Http2ClientSession::do_process_frame_read(int event, VIO *vio, bool inside_frame)
 {
   if (inside_frame) {
     do_complete_frame_read();
diff --git a/proxy/http2/Http2ClientSession.h b/proxy/http2/Http2ClientSession.h
index 804837ab0ef..73b6dd83d9b 100644
--- a/proxy/http2/Http2ClientSession.h
+++ b/proxy/http2/Http2ClientSession.h
@@ -60,6 +60,19 @@ enum class Http2SsnMilestone {
 
 size_t const HTTP2_HEADER_BUFFER_SIZE_INDEX = CLIENT_CONNECTION_FIRST_READ_BUFFER_SIZE_INDEX;
 
+/**
+   @startuml
+   title HTTP/2 Session Handler - state of reading HTTP/2 frame
+   hide empty description
+
+   [*]                           --> state_read_connection_preface : start()
+   state_read_connection_preface --> state_start_frame_read        : receive connection preface
+   state_start_frame_read        --> state_start_frame_read        : do_complete_frame_read()
+   state_start_frame_read        --> state_complete_frame_read     : reading HTTP/2 frame is halfway but no data in the buffer
+   state_complete_frame_read     --> state_start_frame_read        : do_complete_frame_read()
+
+   @enduml
+ */
 class Http2ClientSession : public ProxySession
 {
 public:
@@ -123,15 +136,16 @@ class Http2ClientSession : public ProxySession
 private:
   int main_event_handler(int, void *);
 
+  // SessionHandler(s) - state of reading frame
   int state_read_connection_preface(int, void *);
   int state_start_frame_read(int, void *);
-  int do_start_frame_read(Http2ErrorCode &ret_error);
   int state_complete_frame_read(int, void *);
+
+  // state_start_frame_read and state_complete_frame_read are set up as session event handler.
+  // Both feed into do_process_frame_read which may iterate if there are multiple frames ready on the wire
+  int do_process_frame_read(int event, VIO *vio, bool inside_frame);
+  int do_start_frame_read(Http2ErrorCode &ret_error);
   int do_complete_frame_read();
-  // state_start_frame_read and state_complete_frame_read are set up as
-  // event handler.  Both feed into state_process_frame_read which may iterate
-  // if there are multiple frames ready on the wire
-  int state_process_frame_read(int event, VIO *vio, bool inside_frame);
 
   bool _should_do_something_else();