ceph/src/mds/MDSTableClient.cc

   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 #include <iostream>
  16
  17 #include "MDSMap.h"
  18
  19 #include "MDSContext.h"
  20 #include "msg/Messenger.h"
  21
  22 #include "MDSRank.h"
  23 #include "MDLog.h"
  24 #include "LogSegment.h"
  25
  26 #include "MDSTableClient.h"
  27 #include "events/ETableClient.h"
  28
  29 #include "messages/MMDSTableRequest.h"
  30
  31 #include "common/config.h"
  32
  33 #define dout_context g_ceph_context
  34 #define dout_subsys ceph_subsys_mds
  35 #undef dout_prefix
  36 #define dout_prefix *_dout << "mds." << mds->get_nodeid() << ".tableclient(" << get_mdstable_name(table) << ") "
  37
  38
  39 class C_LoggedAck : public MDSLogContextBase {
  40   MDSTableClient *tc;
  41   version_t tid;
  42   MDSRank *get_mds() override { return tc->mds; }
  43 public:
  44   C_LoggedAck(MDSTableClient *a, version_t t) : tc(a), tid(t) {}
  45   void finish(int r) override {
  46     tc->_logged_ack(tid);
  47   }
  48 };
  49
  50
  51 void MDSTableClient::handle_request(class MMDSTableRequest *m)
  52 {
  53   dout(10) << "handle_request " << *m << dendl;
  54   assert(m->table == table);
  55
  56   version_t tid = m->get_tid();
  57   uint64_t reqid = m->reqid;
  58
  59   switch (m->op) {
  60   case TABLESERVER_OP_QUERY_REPLY:
  61     handle_query_result(m);
  62     break;
  63
  64   case TABLESERVER_OP_AGREE:
  65     if (pending_prepare.count(reqid)) {
  66       dout(10) << "got agree on " << reqid << " atid " << tid << dendl;
  67
  68       assert(g_conf->mds_kill_mdstable_at != 3);
  69
  70       MDSInternalContextBase *onfinish = pending_prepare[reqid].onfinish;
  71       *pending_prepare[reqid].ptid = tid;
  72       if (pending_prepare[reqid].pbl)
  73         *pending_prepare[reqid].pbl = m->bl;
  74       pending_prepare.erase(reqid);
  75       prepared_update[tid] = reqid;
  76       if (onfinish) {
  77         onfinish->complete(0);
  78       }
  79     }
  80     else if (prepared_update.count(tid)) {
  81       dout(10) << "got duplicated agree on " << reqid << " atid " << tid << dendl;
  82       assert(prepared_update[tid] == reqid);
  83       assert(!server_ready);
  84     }
  85     else if (pending_commit.count(tid)) {
  86       dout(10) << "stray agree on " << reqid << " tid " << tid
  87                << ", already committing, will resend COMMIT" << dendl;
  88       assert(!server_ready);
  89       // will re-send commit when receiving the server ready message
  90     }
  91     else {
  92       dout(10) << "stray agree on " << reqid << " tid " << tid
  93                << ", sending ROLLBACK" << dendl;
  94       assert(!server_ready);
  95       MMDSTableRequest *req = new MMDSTableRequest(table, TABLESERVER_OP_ROLLBACK, 0, tid);
  96       mds->send_message_mds(req, mds->get_mds_map()->get_tableserver());
  97     }
  98     break;
  99
 100   case TABLESERVER_OP_ACK:
 101     if (pending_commit.count(tid) &&
 102         pending_commit[tid]->pending_commit_tids[table].count(tid)) {
 103       dout(10) << "got ack on tid " << tid << ", logging" << dendl;
 104
 105       assert(g_conf->mds_kill_mdstable_at != 7);
 106
 107       // remove from committing list
 108       pending_commit[tid]->pending_commit_tids[table].erase(tid);
 109       pending_commit.erase(tid);
 110
 111       // log ACK.
 112       mds->mdlog->start_submit_entry(new ETableClient(table, TABLESERVER_OP_ACK, tid),
 113                                      new C_LoggedAck(this, tid));
 114     } else {
 115       dout(10) << "got stray ack on tid " << tid << ", ignoring" << dendl;
 116     }
 117     break;
 118
 119   case TABLESERVER_OP_SERVER_READY:
 120     assert(!server_ready);
 121     server_ready = true;
 122
 123     if (last_reqid == ~0ULL)
 124       last_reqid = reqid;
 125
 126     resend_queries();
 127     resend_prepares();
 128     resend_commits();
 129     break;
 130
 131   default:
 132     assert(0 == "unrecognized mds_table_client request op");
 133   }
 134
 135   m->put();
 136 }
 137
 138
 139 void MDSTableClient::_logged_ack(version_t tid)
 140 {
 141   dout(10) << "_logged_ack " << tid << dendl;
 142
 143   assert(g_conf->mds_kill_mdstable_at != 8);
 144
 145   // kick any waiters (LogSegment trim)
 146   if (ack_waiters.count(tid)) {
 147     dout(15) << "kicking ack waiters on tid " << tid << dendl;
 148     mds->queue_waiters(ack_waiters[tid]);
 149     ack_waiters.erase(tid);
 150   }
 151 }
 152
 153 void MDSTableClient::_prepare(bufferlist& mutation, version_t *ptid, bufferlist *pbl,
 154                               MDSInternalContextBase *onfinish)
 155 {
 156   if (last_reqid == ~0ULL) {
 157     dout(10) << "tableserver is not ready yet, waiting for request id" << dendl;
 158     waiting_for_reqid.push_back(_pending_prepare(onfinish, ptid, pbl, mutation));
 159     return;
 160   }
 161
 162   uint64_t reqid = ++last_reqid;
 163   dout(10) << "_prepare " << reqid << dendl;
 164
 165   pending_prepare[reqid].mutation = mutation;
 166   pending_prepare[reqid].ptid = ptid;
 167   pending_prepare[reqid].pbl = pbl;
 168   pending_prepare[reqid].onfinish = onfinish;
 169
 170   if (server_ready) {
 171     // send message
 172     MMDSTableRequest *req = new MMDSTableRequest(table, TABLESERVER_OP_PREPARE, reqid);
 173     req->bl = mutation;
 174     mds->send_message_mds(req, mds->get_mds_map()->get_tableserver());
 175   } else
 176     dout(10) << "tableserver is not ready yet, deferring request" << dendl;
 177 }
 178
 179 void MDSTableClient::commit(version_t tid, LogSegment *ls)
 180 {
 181   dout(10) << "commit " << tid << dendl;
 182
 183   assert(prepared_update.count(tid));
 184   prepared_update.erase(tid);
 185
 186   assert(pending_commit.count(tid) == 0);
 187   pending_commit[tid] = ls;
 188   ls->pending_commit_tids[table].insert(tid);
 189
 190   assert(g_conf->mds_kill_mdstable_at != 4);
 191
 192   if (server_ready) {
 193     // send message
 194     MMDSTableRequest *req = new MMDSTableRequest(table, TABLESERVER_OP_COMMIT, 0, tid);
 195     mds->send_message_mds(req, mds->get_mds_map()->get_tableserver());
 196   } else
 197     dout(10) << "tableserver is not ready yet, deferring request" << dendl;
 198 }
 199
 200
 201
 202 // recovery
 203
 204 void MDSTableClient::got_journaled_agree(version_t tid, LogSegment *ls)
 205 {
 206   dout(10) << "got_journaled_agree " << tid << dendl;
 207   ls->pending_commit_tids[table].insert(tid);
 208   pending_commit[tid] = ls;
 209 }
 210
 211 void MDSTableClient::got_journaled_ack(version_t tid)
 212 {
 213   dout(10) << "got_journaled_ack " << tid << dendl;
 214   if (pending_commit.count(tid)) {
 215     pending_commit[tid]->pending_commit_tids[table].erase(tid);
 216     pending_commit.erase(tid);
 217   }
 218 }
 219
 220 void MDSTableClient::resend_commits()
 221 {
 222   for (map<version_t,LogSegment*>::iterator p = pending_commit.begin();
 223        p != pending_commit.end();
 224        ++p) {
 225     dout(10) << "resending commit on " << p->first << dendl;
 226     MMDSTableRequest *req = new MMDSTableRequest(table, TABLESERVER_OP_COMMIT, 0, p->first);
 227     mds->send_message_mds(req, mds->get_mds_map()->get_tableserver());
 228   }
 229 }
 230
 231 void MDSTableClient::resend_prepares()
 232 {
 233   while (!waiting_for_reqid.empty()) {
 234     pending_prepare[++last_reqid] = waiting_for_reqid.front();
 235     waiting_for_reqid.pop_front();
 236   }
 237
 238   for (map<uint64_t, _pending_prepare>::iterator p = pending_prepare.begin();
 239        p != pending_prepare.end();
 240        ++p) {
 241     dout(10) << "resending prepare on " << p->first << dendl;
 242     MMDSTableRequest *req = new MMDSTableRequest(table, TABLESERVER_OP_PREPARE, p->first);
 243     req->bl = p->second.mutation;
 244     mds->send_message_mds(req, mds->get_mds_map()->get_tableserver());
 245   }
 246 }
 247
 248 void MDSTableClient::handle_mds_failure(mds_rank_t who)
 249 {
 250   if (who != mds->get_mds_map()->get_tableserver())
 251     return; // do nothing.
 252
 253   dout(7) << "tableserver mds." << who << " fails" << dendl;
 254   server_ready = false;
 255 }