From 61dd4f03e6e15d59951ff69d95807a3026f5b9c4 Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@newdream.net>
Date: Mon, 22 Nov 2010 22:41:42 -0800
Subject: [PATCH] mon: simplify send_reply code

No need to specify destination in send_reply, as we always have the request
for reference.

Simplify MRoute constructors (keep the ones we use) for tid and bcast
best-effort case.

Do NOT do a best-effort forward of a reply with a tid specified if the tid
is not in the routed-request map.

Signed-off-by: Sage Weil <sage@newdream.net>
---
 src/messages/MRoute.h | 16 ++++++++++------
 src/mon/Monitor.cc    | 36 ++++++++++++++++++++----------------
 src/mon/Monitor.h     |  5 +----
 3 files changed, 31 insertions(+), 26 deletions(-)

diff --git a/src/messages/MRoute.h b/src/messages/MRoute.h
index b35153119a0f2..076b8f996700c 100644
--- a/src/messages/MRoute.h
+++ b/src/messages/MRoute.h
@@ -26,10 +26,10 @@ struct MRoute : public Message {
   entity_inst_t dest;
   
   MRoute() : Message(MSG_ROUTE), msg(NULL) {}
-  MRoute(uint64_t t, Message *m, entity_inst_t i) :
-    Message(MSG_ROUTE), session_mon_tid(t), msg(m), dest(i) {}
-  MRoute(uint64_t t, bufferlist bl, entity_inst_t i) :
-    Message(MSG_ROUTE), session_mon_tid(t), dest(i) {
+  MRoute(uint64_t t, Message *m) :
+    Message(MSG_ROUTE), session_mon_tid(t), msg(m) {}
+  MRoute(bufferlist bl, entity_inst_t i) :
+    Message(MSG_ROUTE), session_mon_tid(0), dest(i) {
     bufferlist::iterator p = bl.begin();
     msg = decode_message(p);
   }
@@ -54,9 +54,13 @@ public:
   const char *get_type_name() { return "route"; }
   void print(ostream& o) {
     if (msg)
-      o << "route(" << *msg << " to " << dest << ")";
+      o << "route(" << *msg;
     else
-      o << "route(??? to " << dest << ")";
+      o << "route(???";
+    if (session_mon_tid)
+      o << " tid " << session_mon_tid << ")";
+    else
+      o << " to " << dest << ")";
   }
 };
 
diff --git a/src/mon/Monitor.cc b/src/mon/Monitor.cc
index 5d7ecd2fa28d4..dbaad25963378 100644
--- a/src/mon/Monitor.cc
+++ b/src/mon/Monitor.cc
@@ -451,24 +451,24 @@ void Monitor::try_send_message(Message *m, entity_inst_t to)
 
   for (int i=0; i<(int)monmap->size(); i++) {
     if (i != rank)
-      messenger->send_message(new MRoute(0, bl, to),
-			      monmap->get_inst(i));
+      messenger->send_message(new MRoute(bl, to), monmap->get_inst(i));
   }
 }
 
-void Monitor::send_reply(PaxosServiceMessage *req, Message *reply, entity_inst_t to)
+void Monitor::send_reply(PaxosServiceMessage *req, Message *reply)
 {
   MonSession *session = (MonSession*)req->get_connection()->get_priv();
   if (!session) {
     dout(2) << "send_reply no session, dropping reply " << *reply
-	    << " to " << req << " " << *req << " for " << to << dendl;
+	    << " to " << req << " " << *req << dendl;
     reply->put();
     return;
   }
   if (session->proxy_con) {
-    dout(15) << "send_reply routing reply to " << to << " via mon" << req->session_mon
+    dout(15) << "send_reply routing reply to " << req->get_connection()->get_peer_addr()
+	     << " via mon" << req->session_mon
 	     << " for request " << *req << dendl;
-    messenger->send_message(new MRoute(session->proxy_tid, reply, to),
+    messenger->send_message(new MRoute(session->proxy_tid, reply),
 			    session->proxy_con);    
   } else {
     messenger->send_message(reply, session->con);
@@ -490,21 +490,25 @@ void Monitor::handle_route(MRoute *m)
   dout(10) << "handle_route " << *m->msg << " to " << m->dest << dendl;
   
   // look it up
-  if (routed_requests.count(m->session_mon_tid)) {
-    RoutedRequest *rr = routed_requests[m->session_mon_tid];
-    messenger->send_message(m->msg, rr->session->inst);
-    m->msg = NULL;
-    routed_requests.erase(m->session_mon_tid);
-    rr->session->routed_request_tids.insert(rr->tid);
-    delete rr;
+  if (m->session_mon_tid) {
+    if (routed_requests.count(m->session_mon_tid)) {
+      RoutedRequest *rr = routed_requests[m->session_mon_tid];
+      messenger->send_message(m->msg, rr->session->inst);
+      m->msg = NULL;
+      routed_requests.erase(m->session_mon_tid);
+      rr->session->routed_request_tids.insert(rr->tid);
+      delete rr;
+    } else {
+      dout(10) << " don't have routed request tid " << m->session_mon_tid << dendl;
+    }
   } else {
-    dout(10) << " don't have routed request tid " << m->session_mon_tid
-	     << ", trying to send anyway" << dendl;
+    dout(10) << " not a routed request, trying to send anyway" << dendl;
     messenger->lazy_send_message(m->msg, m->dest);
     m->msg = NULL;
   }
   m->put();
-  if (session) session->put();
+  if (session)
+    session->put();
 }
 
 void Monitor::resend_routed_requests()
diff --git a/src/mon/Monitor.h b/src/mon/Monitor.h
index 60d5f2aa22b27..0c1b1c5e11c95 100644
--- a/src/mon/Monitor.h
+++ b/src/mon/Monitor.h
@@ -175,10 +175,7 @@ public:
   void forward_request_leader(PaxosServiceMessage *req);
   void handle_forward(MForward *m);
   void try_send_message(Message *m, entity_inst_t to);
-  void send_reply(PaxosServiceMessage *req, Message *reply, entity_inst_t to);
-  void send_reply(PaxosServiceMessage *req, Message *reply) {
-    send_reply(req, reply, req->get_orig_source_inst());
-  }
+  void send_reply(PaxosServiceMessage *req, Message *reply);
   void resend_routed_requests();
   void remove_session(MonSession *s);
 
-- 
2.39.5