ceph/src/mon/QuorumService.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) 2013 Inktank, Inc
   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 #ifndef CEPH_MON_QUORUM_SERVICE_H
  15 #define CEPH_MON_QUORUM_SERVICE_H
  16
  17 #include <errno.h>
  18
  19 #include "include/types.h"
  20 #include "include/Context.h"
  21 #include "common/RefCountedObj.h"
  22 #include "common/config.h"
  23
  24 #include "mon/Monitor.h"
  25
  26 class QuorumService
  27 {
  28   Context *tick_event = nullptr;
  29   double tick_period;
  30
  31 public:
  32   enum {
  33     SERVICE_HEALTH                   = 0x01,
  34     SERVICE_TIMECHECK                = 0x02,
  35     SERVICE_CONFIG_KEY               = 0x03,
  36   };
  37
  38 protected:
  39   Monitor *mon;
  40   epoch_t epoch;
  41
  42   QuorumService(Monitor *m) :
  43     tick_period(g_conf->mon_tick_interval),
  44     mon(m),
  45     epoch(0)
  46   {
  47   }
  48
  49   void cancel_tick() {
  50     if (tick_event)
  51       mon->timer.cancel_event(tick_event);
  52     tick_event = NULL;
  53   }
  54
  55   void start_tick() {
  56     generic_dout(10) << __func__ << dendl;
  57
  58     cancel_tick();
  59     if (tick_period <= 0)
  60       return;
  61
  62     tick_event = new C_MonContext(mon, [this](int r) {
  63         if (r < 0)
  64           return;
  65         tick();
  66       });
  67     mon->timer.add_event_after(tick_period, tick_event);
  68   }
  69
  70   void set_update_period(double t) {
  71     tick_period = t;
  72   }
  73
  74   bool in_quorum() {
  75     return (mon->is_leader() || mon->is_peon());
  76   }
  77
  78   virtual bool service_dispatch(MonOpRequestRef op) = 0;
  79   virtual void service_tick() = 0;
  80   virtual void service_shutdown() = 0;
  81
  82   virtual void start_epoch() = 0;
  83   virtual void finish_epoch() = 0;
  84   virtual void cleanup() = 0;
  85
  86 public:
  87   virtual ~QuorumService() { }
  88
  89   void start(epoch_t new_epoch) {
  90     epoch = new_epoch;
  91     start_epoch();
  92   }
  93
  94   void finish() {
  95     generic_dout(20) << "QuorumService::finish" << dendl;
  96     finish_epoch();
  97   }
  98
  99   epoch_t get_epoch() const {
 100     return epoch;
 101   }
 102
 103   bool dispatch(MonOpRequestRef op) {
 104     return service_dispatch(op);
 105   }
 106
 107   void tick() {
 108     service_tick();
 109     start_tick();
 110   }
 111
 112   void shutdown() {
 113     generic_dout(0) << "quorum service shutdown" << dendl;
 114     cancel_tick();
 115     service_shutdown();
 116   }
 117
 118   virtual void init() { }
 119
 120   virtual void get_health(Formatter *f,
 121                           list<pair<health_status_t,string> >& summary,
 122                           list<pair<health_status_t,string> > *detail) = 0;
 123   virtual int get_type() = 0;
 124   virtual string get_name() const = 0;
 125
 126 };
 127
 128 #endif /* CEPH_MON_QUORUM_SERVICE_H */