MOSDRepOp/ MOSDRepOpReply: Simple Messenger optimization

src/messages/MOSDRepOp.h

@@ -34,9 +34,14 @@ class MOSDRepOp : public Message {
   // metadata from original request
   osd_reqid_t reqid;
 
+  spg_t pgid;
+
+  bufferlist::iterator p;
+  // Decoding flags. Decoding is only needed for messages catched by pipe reader.
+  bool final_decode_needed;
+
   // subop
   pg_shard_t from;
-  spg_t pgid;
   hobject_t poid;
 
   __u8 acks_wanted;
@@ -64,10 +69,16 @@ class MOSDRepOp : public Message {
   }
 
   virtual void decode_payload() {
-    bufferlist::iterator p = payload.begin();
+    p = payload.begin();
+    // splitted to partial and final
     ::decode(map_epoch, p);
     ::decode(reqid, p);
     ::decode(pgid, p);
+  }
+
+  void finish_decode() {
+    if (!final_decode_needed)
+      return; // Message is already final decoded
     ::decode(poid, p);
 
     ::decode(acks_wanted, p);
@@ -83,6 +94,7 @@ class MOSDRepOp : public Message {
     ::decode(from, p);
     ::decode(updated_hit_set_history, p);
     ::decode(pg_trim_rollback_to, p);
+    final_decode_needed = false;
   }
 
   virtual void encode_payload(uint64_t features) {
@@ -105,15 +117,17 @@ class MOSDRepOp : public Message {
 
   MOSDRepOp()
     : Message(MSG_OSD_REPOP, HEAD_VERSION, COMPAT_VERSION),
-      map_epoch(0), acks_wanted (0) {}
+      map_epoch(0),
+      final_decode_needed(true), acks_wanted (0) {}
   MOSDRepOp(osd_reqid_t r, pg_shard_t from,
 	    spg_t p, const hobject_t& po, int aw,
 	    epoch_t mape, ceph_tid_t rtid, eversion_t v)
     : Message(MSG_OSD_REPOP, HEAD_VERSION, COMPAT_VERSION),
       map_epoch(mape),
       reqid(r),
-      from(from),
       pgid(p),
+      final_decode_needed(false),
+      from(from),
       poid(po),
       acks_wanted(aw),
       version(v) {
@@ -126,11 +140,12 @@ class MOSDRepOp : public Message {
   const char *get_type_name() const { return "osd_repop"; }
   void print(ostream& out) const {
     out << "osd_repop(" << reqid
-	<< " " << pgid
-	<< " " << poid;
-    out << " v " << version;
-    if (updated_hit_set_history)
-      out << ", has_updated_hit_set_history";
+          << " " << pgid;
+    if (!final_decode_needed) {
+        out << " " << poid << " v " << version;
+      if (updated_hit_set_history)
+        out << ", has_updated_hit_set_history";
+    }
     out << ")";
   }
 };

src/messages/MOSDRepOpReply.h

@@ -46,18 +46,26 @@ class MOSDRepOpReply : public Message {
   // piggybacked osd state
   eversion_t last_complete_ondisk;
 
+  bufferlist::iterator p;
+  // Decoding flags. Decoding is only needed for messages catched by pipe reader.
+  bool final_decode_needed;
 
   virtual void decode_payload() {
-    bufferlist::iterator p = payload.begin();
+    p = payload.begin();
     ::decode(map_epoch, p);
     ::decode(reqid, p);
     ::decode(pgid, p);
+  }
 
+  void finish_decode() {
+    if (!final_decode_needed)
+      return; // Message is already final decoded
     ::decode(ack_type, p);
     ::decode(result, p);
     ::decode(last_complete_ondisk, p);
 
     ::decode(from, p);
+    final_decode_needed = false;
   }
   virtual void encode_payload(uint64_t features) {
     ::encode(map_epoch, payload);
@@ -91,12 +99,14 @@ class MOSDRepOpReply : public Message {
     from(from),
     pgid(req->pgid.pgid, req->from.shard),
     ack_type(at),
-    result(result_) {
+    result(result_),
+    final_decode_needed(false) {
     set_tid(req->get_tid());
   }
   MOSDRepOpReply() 
     : Message(MSG_OSD_REPOPREPLY), map_epoch(0),  
-      ack_type(0), result(0) {}
+      ack_type(0), result(0),
+      final_decode_needed(true) {}
 private:
   ~MOSDRepOpReply() {}
 
@@ -105,14 +115,16 @@ class MOSDRepOpReply : public Message {
 
   void print(ostream& out) const {
     out << "osd_repop_reply(" << reqid
-	<< " " << pgid;
-    if (ack_type & CEPH_OSD_FLAG_ONDISK)
-      out << " ondisk";
-    if (ack_type & CEPH_OSD_FLAG_ONNVRAM)
-      out << " onnvram";
-    if (ack_type & CEPH_OSD_FLAG_ACK)
-      out << " ack";
-    out << ", result = " << result;
+        << " " << pgid;
+    if (!final_decode_needed) {
+      if (ack_type & CEPH_OSD_FLAG_ONDISK)
+        out << " ondisk";
+      if (ack_type & CEPH_OSD_FLAG_ONNVRAM)
+        out << " onnvram";
+      if (ack_type & CEPH_OSD_FLAG_ACK)
+        out << " ack";
+      out << ", result = " << result;
+    }
     out << ")";
   }
 

src/messages/MOSDSubOp.h

@@ -172,6 +172,8 @@ class MOSDSubOp : public Message {
     }
   }
 
+  void finish_decode() { }
+
   virtual void encode_payload(uint64_t features) {
     ::encode(map_epoch, payload);
     ::encode(reqid, payload);

src/messages/MOSDSubOpReply.h

@@ -85,6 +85,9 @@ class MOSDSubOpReply : public Message {
       pgid.shard = shard_id_t::NO_SHARD;
     }
   }
+
+  void finish_decode() { }
+
   virtual void encode_payload(uint64_t features) {
     ::encode(map_epoch, payload);
     ::encode(reqid, payload);

src/osd/ReplicatedBackend.cc

@@ -666,6 +666,7 @@ template<typename T, int MSGTYPE>
 void ReplicatedBackend::sub_op_modify_reply(OpRequestRef op)
 {
   T *r = static_cast<T *>(op->get_req());
+  r->finish_decode();
   assert(r->get_header().type == MSGTYPE);
   assert(MSGTYPE == MSG_OSD_SUBOPREPLY || MSGTYPE == MSG_OSD_REPOPREPLY);
 
@@ -1117,6 +1118,7 @@ template<typename T, int MSGTYPE>
 void ReplicatedBackend::sub_op_modify_impl(OpRequestRef op)
 {
   T *m = static_cast<T *>(op->get_req());
+  m->finish_decode();
   int msg_type = m->get_type();
   assert(MSGTYPE == msg_type);
   assert(msg_type == MSG_OSD_SUBOP || msg_type == MSG_OSD_REPOP);