ceph/src/messages/MOSDPing.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph - scalable distributed file system
   5  *
   6  * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
   7  *
   8  * This is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License version 2.1, as published by the Free Software
  11  * Foundation.  See file COPYING.
  12  *
  13  */
  14
  15
  16 /**
  17  * This is used to send pings between daemons (so far, the OSDs) for
  18  * heartbeat purposes. We include a timestamp and distinguish between
  19  * outgoing pings and responses to those. If you set the
  20  * min_message in the constructor, the message will inflate itself
  21  * to the specified size -- this is good for dealing with network
  22  * issues with jumbo frames. See http://tracker.ceph.com/issues/20087
  23  *
  24  */
  25
  26 #ifndef CEPH_MOSDPING_H
  27 #define CEPH_MOSDPING_H
  28
  29 #include "common/Clock.h"
  30
  31 #include "msg/Message.h"
  32 #include "osd/osd_types.h"
  33
  34
  35 class MOSDPing : public Message {
  36
  37   static const int HEAD_VERSION = 4;
  38   static const int COMPAT_VERSION = 4;
  39
  40  public:
  41   enum {
  42     HEARTBEAT = 0,
  43     START_HEARTBEAT = 1,
  44     YOU_DIED = 2,
  45     STOP_HEARTBEAT = 3,
  46     PING = 4,
  47     PING_REPLY = 5,
  48   };
  49   const char *get_op_name(int op) const {
  50     switch (op) {
  51     case HEARTBEAT: return "heartbeat";
  52     case START_HEARTBEAT: return "start_heartbeat";
  53     case STOP_HEARTBEAT: return "stop_heartbeat";
  54     case YOU_DIED: return "you_died";
  55     case PING: return "ping";
  56     case PING_REPLY: return "ping_reply";
  57     default: return "???";
  58     }
  59   }
  60
  61   uuid_d fsid;
  62   epoch_t map_epoch;
  63   __u8 op;
  64   utime_t stamp;
  65   uint32_t min_message_size;
  66
  67   MOSDPing(const uuid_d& f, epoch_t e, __u8 o, utime_t s, uint32_t min_message)
  68     : Message(MSG_OSD_PING, HEAD_VERSION, COMPAT_VERSION),
  69       fsid(f), map_epoch(e), op(o), stamp(s), min_message_size(min_message)
  70   { }
  71   MOSDPing()
  72     : Message(MSG_OSD_PING, HEAD_VERSION, COMPAT_VERSION), min_message_size(0)
  73   {}
  74 private:
  75   ~MOSDPing() override {}
  76
  77 public:
  78   void decode_payload() override {
  79     bufferlist::iterator p = payload.begin();
  80     ::decode(fsid, p);
  81     ::decode(map_epoch, p);
  82     if (header.version < 4) {
  83       osd_peer_stat_t peer_stat;
  84       epoch_t peer_as_of_epoch;
  85       ::decode(peer_as_of_epoch, p);
  86       ::decode(op, p);
  87       ::decode(peer_stat, p);
  88     } else {
  89       ::decode(op, p);
  90     }
  91     ::decode(stamp, p);
  92     if (header.version >= 3) {
  93       int payload_mid_length = p.get_off();
  94       uint32_t size;
  95       ::decode(size, p);
  96       p.advance(size);
  97       min_message_size = size + payload_mid_length;
  98     }
  99   }
 100   void encode_payload(uint64_t features) override {
 101     ::encode(fsid, payload);
 102     ::encode(map_epoch, payload);
 103
 104     // with luminous, we drop peer_as_of_epoch and peer_stat
 105     if (!HAVE_FEATURE(features, SERVER_LUMINOUS)) {
 106       epoch_t dummy_epoch = {};
 107       osd_peer_stat_t dummy_stat = {};
 108       header.version = 3;
 109       header.compat_version = 2;
 110       ::encode(dummy_epoch, payload);
 111       ::encode(op, payload);
 112       ::encode(dummy_stat, payload);
 113     } else {
 114       ::encode(op, payload);
 115     }
 116     ::encode(stamp, payload);
 117     size_t s = 0;
 118     if (min_message_size > payload.length())
 119       s = min_message_size - payload.length();
 120     ::encode((uint32_t)s, payload);
 121     if (s) {
 122       // this should be big enough for normal min_message padding sizes. since
 123       // we are targetting jumbo ethernet frames around 9000 bytes, 16k should
 124       // be more than sufficient!  the compiler will statically zero this so
 125       // that at runtime we are only adding a bufferptr reference to it.
 126       static char zeros[16384] = {};
 127       while (s > sizeof(zeros)) {
 128         payload.append(buffer::create_static(sizeof(zeros), zeros));
 129         s -= sizeof(zeros);
 130       }
 131       if (s) {
 132         payload.append(buffer::create_static(s, zeros));
 133       }
 134     }
 135   }
 136
 137   const char *get_type_name() const override { return "osd_ping"; }
 138   void print(ostream& out) const override {
 139     out << "osd_ping(" << get_op_name(op)
 140         << " e" << map_epoch
 141         << " stamp " << stamp
 142         << ")";
 143   }
 144 };
 145
 146 #endif