ceph/src/osd/PGLog.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  * Copyright (C) 2013 Cloudwatt <libre.licensing@cloudwatt.com>
   8  *
   9  * Author: Loic Dachary <loic@dachary.org>
  10  *
  11  * This is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU Lesser General Public
  13  * License version 2.1, as published by the Free Software
  14  * Foundation.  See file COPYING.
  15  *
  16  */
  17 #ifndef CEPH_PG_LOG_H
  18 #define CEPH_PG_LOG_H
  19
  20 // re-include our assert to clobber boost's
  21 #include "include/assert.h"
  22 #include "osd_types.h"
  23 #include "os/ObjectStore.h"
  24 #include <list>
  25 using namespace std;
  26
  27 #define PGLOG_INDEXED_OBJECTS          (1 << 0)
  28 #define PGLOG_INDEXED_CALLER_OPS       (1 << 1)
  29 #define PGLOG_INDEXED_EXTRA_CALLER_OPS (1 << 2)
  30 #define PGLOG_INDEXED_ALL              (PGLOG_INDEXED_OBJECTS | PGLOG_INDEXED_CALLER_OPS | PGLOG_INDEXED_EXTRA_CALLER_OPS)
  31
  32 class CephContext;
  33
  34 struct PGLog : DoutPrefixProvider {
  35   DoutPrefixProvider *prefix_provider;
  36   string gen_prefix() const override {
  37     return prefix_provider ? prefix_provider->gen_prefix() : "";
  38   }
  39   unsigned get_subsys() const override {
  40     return prefix_provider ? prefix_provider->get_subsys() :
  41       (unsigned)ceph_subsys_osd;
  42   }
  43   CephContext *get_cct() const override {
  44     return cct;
  45   }
  46
  47   ////////////////////////////// sub classes //////////////////////////////
  48   struct LogEntryHandler {
  49     virtual void rollback(
  50       const pg_log_entry_t &entry) = 0;
  51     virtual void rollforward(
  52       const pg_log_entry_t &entry) = 0;
  53     virtual void trim(
  54       const pg_log_entry_t &entry) = 0;
  55     virtual void remove(
  56       const hobject_t &hoid) = 0;
  57     virtual void try_stash(
  58       const hobject_t &hoid,
  59       version_t v) = 0;
  60     virtual ~LogEntryHandler() {}
  61   };
  62
  63   /* Exceptions */
  64   class read_log_and_missing_error : public buffer::error {
  65   public:
  66     explicit read_log_and_missing_error(const char *what) {
  67       snprintf(buf, sizeof(buf), "read_log_and_missing_error: %s", what);
  68     }
  69     const char *what() const throw () override {
  70       return buf;
  71     }
  72   private:
  73     char buf[512];
  74   };
  75
  76 public:
  77   /**
  78    * IndexLog - adds in-memory index of the log, by oid.
  79    * plus some methods to manipulate it all.
  80    */
  81   struct IndexedLog : public pg_log_t {
  82     mutable ceph::unordered_map<hobject_t,pg_log_entry_t*> objects;  // ptrs into log.  be careful!
  83     mutable ceph::unordered_map<osd_reqid_t,pg_log_entry_t*> caller_ops;
  84     mutable ceph::unordered_multimap<osd_reqid_t,pg_log_entry_t*> extra_caller_ops;
  85
  86     // recovery pointers
  87     list<pg_log_entry_t>::iterator complete_to; // not inclusive of referenced item
  88     version_t last_requested = 0;               // last object requested by primary
  89
  90     //
  91   private:
  92     mutable __u16 indexed_data = 0;
  93     /**
  94      * rollback_info_trimmed_to_riter points to the first log entry <=
  95      * rollback_info_trimmed_to
  96      *
  97      * It's a reverse_iterator because rend() is a natural representation for
  98      * tail, and rbegin() works nicely for head.
  99      */
 100     mempool::osd::list<pg_log_entry_t>::reverse_iterator
 101       rollback_info_trimmed_to_riter;
 102
 103     template <typename F>
 104     void advance_can_rollback_to(eversion_t to, F &&f) {
 105       if (to > can_rollback_to)
 106         can_rollback_to = to;
 107
 108       if (to > rollback_info_trimmed_to)
 109         rollback_info_trimmed_to = to;
 110
 111       while (rollback_info_trimmed_to_riter != log.rbegin()) {
 112         --rollback_info_trimmed_to_riter;
 113         if (rollback_info_trimmed_to_riter->version > rollback_info_trimmed_to) {
 114           ++rollback_info_trimmed_to_riter;
 115           break;
 116         }
 117         f(*rollback_info_trimmed_to_riter);
 118       }
 119     }
 120
 121     void reset_rollback_info_trimmed_to_riter() {
 122       rollback_info_trimmed_to_riter = log.rbegin();
 123       while (rollback_info_trimmed_to_riter != log.rend() &&
 124              rollback_info_trimmed_to_riter->version > rollback_info_trimmed_to)
 125         ++rollback_info_trimmed_to_riter;
 126     }
 127
 128     // indexes objects, caller ops and extra caller ops
 129   public:
 130     IndexedLog() :
 131       complete_to(log.end()),
 132       last_requested(0),
 133       indexed_data(0),
 134       rollback_info_trimmed_to_riter(log.rbegin())
 135       {}
 136
 137     template <typename... Args>
 138     IndexedLog(Args&&... args) :
 139       pg_log_t(std::forward<Args>(args)...),
 140       complete_to(log.end()),
 141       last_requested(0),
 142       indexed_data(0),
 143       rollback_info_trimmed_to_riter(log.rbegin()) {
 144       reset_rollback_info_trimmed_to_riter();
 145       index();
 146     }
 147
 148     IndexedLog(const IndexedLog &rhs) :
 149       pg_log_t(rhs),
 150       complete_to(log.end()),
 151       last_requested(rhs.last_requested),
 152       indexed_data(0),
 153       rollback_info_trimmed_to_riter(log.rbegin()) {
 154       reset_rollback_info_trimmed_to_riter();
 155       index(rhs.indexed_data);
 156     }
 157     IndexedLog &operator=(const IndexedLog &rhs) {
 158       this->~IndexedLog();
 159       new (this) IndexedLog(rhs);
 160       return *this;
 161     }
 162
 163     void trim_rollback_info_to(eversion_t to, LogEntryHandler *h) {
 164       advance_can_rollback_to(
 165         to,
 166         [&](pg_log_entry_t &entry) {
 167           h->trim(entry);
 168         });
 169     }
 170     void roll_forward_to(eversion_t to, LogEntryHandler *h) {
 171       advance_can_rollback_to(
 172         to,
 173         [&](pg_log_entry_t &entry) {
 174           h->rollforward(entry);
 175         });
 176     }
 177
 178     void skip_can_rollback_to_to_head() {
 179       advance_can_rollback_to(head, [&](const pg_log_entry_t &entry) {});
 180     }
 181
 182     mempool::osd::list<pg_log_entry_t> rewind_from_head(eversion_t newhead) {
 183       auto divergent = pg_log_t::rewind_from_head(newhead);
 184       index();
 185       reset_rollback_info_trimmed_to_riter();
 186       return divergent;
 187     }
 188
 189     template <typename T>
 190     void scan_log_after(
 191       const eversion_t &bound, ///< [in] scan entries > bound
 192       T &&f) const {
 193       auto iter = log.rbegin();
 194       while (iter != log.rend() && iter->version > bound)
 195         ++iter;
 196
 197       while (true) {
 198         if (iter == log.rbegin())
 199           break;
 200         f(*(--iter));
 201       }
 202     }
 203
 204     /****/
 205     void claim_log_and_clear_rollback_info(const pg_log_t& o) {
 206       // we must have already trimmed the old entries
 207       assert(rollback_info_trimmed_to == head);
 208       assert(rollback_info_trimmed_to_riter == log.rbegin());
 209
 210       *this = IndexedLog(o);
 211
 212       skip_can_rollback_to_to_head();
 213       index();
 214     }
 215
 216     void split_out_child(
 217       pg_t child_pgid,
 218       unsigned split_bits,
 219       IndexedLog *target);
 220
 221     void zero() {
 222       // we must have already trimmed the old entries
 223       assert(rollback_info_trimmed_to == head);
 224       assert(rollback_info_trimmed_to_riter == log.rbegin());
 225
 226       unindex();
 227       pg_log_t::clear();
 228       rollback_info_trimmed_to_riter = log.rbegin();
 229       reset_recovery_pointers();
 230     }
 231     void clear() {
 232       skip_can_rollback_to_to_head();
 233       zero();
 234     }
 235     void reset_recovery_pointers() {
 236       complete_to = log.end();
 237       last_requested = 0;
 238     }
 239
 240     bool logged_object(const hobject_t& oid) const {
 241       if (!(indexed_data & PGLOG_INDEXED_OBJECTS)) {
 242          index_objects();
 243       }
 244       return objects.count(oid);
 245     }
 246
 247     bool logged_req(const osd_reqid_t &r) const {
 248       if (!(indexed_data & PGLOG_INDEXED_CALLER_OPS)) {
 249         index_caller_ops();
 250       }
 251       if (!caller_ops.count(r)) {
 252         if (!(indexed_data & PGLOG_INDEXED_EXTRA_CALLER_OPS)) {
 253           index_extra_caller_ops();
 254         }
 255         return extra_caller_ops.count(r);
 256       }
 257       return true;
 258     }
 259
 260     bool get_request(
 261       const osd_reqid_t &r,
 262       eversion_t *version,
 263       version_t *user_version,
 264       int *return_code) const {
 265       assert(version);
 266       assert(user_version);
 267       assert(return_code);
 268       ceph::unordered_map<osd_reqid_t,pg_log_entry_t*>::const_iterator p;
 269       if (!(indexed_data & PGLOG_INDEXED_CALLER_OPS)) {
 270         index_caller_ops();
 271       }
 272       p = caller_ops.find(r);
 273       if (p != caller_ops.end()) {
 274         *version = p->second->version;
 275         *user_version = p->second->user_version;
 276         *return_code = p->second->return_code;
 277         return true;
 278       }
 279
 280       // warning: we will return *a* request for this reqid, but not
 281       // necessarily the most recent.
 282       if (!(indexed_data & PGLOG_INDEXED_EXTRA_CALLER_OPS)) {
 283         index_extra_caller_ops();
 284       }
 285       p = extra_caller_ops.find(r);
 286       if (p != extra_caller_ops.end()) {
 287         for (vector<pair<osd_reqid_t, version_t> >::const_iterator i =
 288                p->second->extra_reqids.begin();
 289              i != p->second->extra_reqids.end();
 290              ++i) {
 291           if (i->first == r) {
 292             *version = p->second->version;
 293             *user_version = i->second;
 294             *return_code = p->second->return_code;
 295             return true;
 296           }
 297         }
 298         assert(0 == "in extra_caller_ops but not extra_reqids");
 299       }
 300       return false;
 301     }
 302
 303     /// get a (bounded) list of recent reqids for the given object
 304     void get_object_reqids(const hobject_t& oid, unsigned max,
 305                            vector<pair<osd_reqid_t, version_t> > *pls) const {
 306        // make sure object is present at least once before we do an
 307        // O(n) search.
 308       if (!(indexed_data & PGLOG_INDEXED_OBJECTS)) {
 309         index_objects();
 310       }
 311       if (objects.count(oid) == 0)
 312         return;
 313       for (list<pg_log_entry_t>::const_reverse_iterator i = log.rbegin();
 314            i != log.rend();
 315            ++i) {
 316         if (i->soid == oid) {
 317           if (i->reqid_is_indexed())
 318             pls->push_back(make_pair(i->reqid, i->user_version));
 319           pls->insert(pls->end(), i->extra_reqids.begin(), i->extra_reqids.end());
 320           if (pls->size() >= max) {
 321             if (pls->size() > max) {
 322               pls->resize(max);
 323             }
 324             return;
 325           }
 326         }
 327       }
 328     }
 329
 330     void index(__u16 to_index = PGLOG_INDEXED_ALL) const {
 331       if (to_index & PGLOG_INDEXED_OBJECTS)
 332         objects.clear();
 333       if (to_index & PGLOG_INDEXED_CALLER_OPS)
 334         caller_ops.clear();
 335       if (to_index & PGLOG_INDEXED_EXTRA_CALLER_OPS)
 336         extra_caller_ops.clear();
 337
 338       for (list<pg_log_entry_t>::const_iterator i = log.begin();
 339            i != log.end();
 340            ++i) {
 341         if (to_index & PGLOG_INDEXED_OBJECTS) {
 342           if (i->object_is_indexed()) {
 343             objects[i->soid] = const_cast<pg_log_entry_t*>(&(*i));
 344           }
 345         }
 346
 347         if (to_index & PGLOG_INDEXED_CALLER_OPS) {
 348           if (i->reqid_is_indexed()) {
 349             caller_ops[i->reqid] = const_cast<pg_log_entry_t*>(&(*i));
 350           }
 351         }
 352
 353         if (to_index & PGLOG_INDEXED_EXTRA_CALLER_OPS) {
 354           for (vector<pair<osd_reqid_t, version_t> >::const_iterator j =
 355                  i->extra_reqids.begin();
 356                j != i->extra_reqids.end();
 357                ++j) {
 358             extra_caller_ops.insert(
 359               make_pair(j->first, const_cast<pg_log_entry_t*>(&(*i))));
 360           }
 361         }
 362       }
 363
 364       indexed_data |= to_index;
 365     }
 366
 367     void index_objects() const {
 368       index(PGLOG_INDEXED_OBJECTS);
 369     }
 370
 371     void index_caller_ops() const {
 372       index(PGLOG_INDEXED_CALLER_OPS);
 373     }
 374
 375     void index_extra_caller_ops() const {
 376       index(PGLOG_INDEXED_EXTRA_CALLER_OPS);
 377     }
 378
 379     void index(pg_log_entry_t& e) {
 380       if ((indexed_data & PGLOG_INDEXED_OBJECTS) && e.object_is_indexed()) {
 381         if (objects.count(e.soid) == 0 ||
 382             objects[e.soid]->version < e.version)
 383           objects[e.soid] = &e;
 384       }
 385       if (indexed_data & PGLOG_INDEXED_CALLER_OPS) {
 386         // divergent merge_log indexes new before unindexing old
 387         if (e.reqid_is_indexed()) {
 388           caller_ops[e.reqid] = &e;
 389         }
 390       }
 391       if (indexed_data & PGLOG_INDEXED_EXTRA_CALLER_OPS) {
 392         for (vector<pair<osd_reqid_t, version_t> >::const_iterator j =
 393                e.extra_reqids.begin();
 394              j != e.extra_reqids.end();
 395              ++j) {
 396           extra_caller_ops.insert(make_pair(j->first, &e));
 397         }
 398       }
 399     }
 400     void unindex() {
 401       objects.clear();
 402       caller_ops.clear();
 403       extra_caller_ops.clear();
 404       indexed_data = 0;
 405     }
 406     void unindex(pg_log_entry_t& e) {
 407       // NOTE: this only works if we remove from the _tail_ of the log!
 408       if (indexed_data & PGLOG_INDEXED_OBJECTS) {
 409         if (objects.count(e.soid) && objects[e.soid]->version == e.version)
 410           objects.erase(e.soid);
 411       }
 412       if (e.reqid_is_indexed()) {
 413         if (indexed_data & PGLOG_INDEXED_CALLER_OPS) {
 414           // divergent merge_log indexes new before unindexing old
 415           if (caller_ops.count(e.reqid) && caller_ops[e.reqid] == &e)
 416             caller_ops.erase(e.reqid);
 417         }
 418       }
 419       if (indexed_data & PGLOG_INDEXED_EXTRA_CALLER_OPS) {
 420         for (vector<pair<osd_reqid_t, version_t> >::const_iterator j =
 421                e.extra_reqids.begin();
 422              j != e.extra_reqids.end();
 423              ++j) {
 424           for (ceph::unordered_multimap<osd_reqid_t,pg_log_entry_t*>::iterator k =
 425                  extra_caller_ops.find(j->first);
 426                k != extra_caller_ops.end() && k->first == j->first;
 427                ++k) {
 428             if (k->second == &e) {
 429               extra_caller_ops.erase(k);
 430               break;
 431             }
 432           }
 433         }
 434       }
 435     }
 436
 437     // actors
 438     void add(const pg_log_entry_t& e, bool applied = true) {
 439       if (!applied) {
 440         assert(get_can_rollback_to() == head);
 441       }
 442
 443       // add to log
 444       log.push_back(e);
 445
 446       // riter previously pointed to the previous entry
 447       if (rollback_info_trimmed_to_riter == log.rbegin())
 448         ++rollback_info_trimmed_to_riter;
 449
 450       assert(e.version > head);
 451       assert(head.version == 0 || e.version.version > head.version);
 452       head = e.version;
 453
 454       // to our index
 455       if ((indexed_data & PGLOG_INDEXED_OBJECTS) && e.object_is_indexed()) {
 456         objects[e.soid] = &(log.back());
 457       }
 458       if (indexed_data & PGLOG_INDEXED_CALLER_OPS) {
 459         if (e.reqid_is_indexed()) {
 460           caller_ops[e.reqid] = &(log.back());
 461         }
 462       }
 463
 464       if (indexed_data & PGLOG_INDEXED_EXTRA_CALLER_OPS) {
 465         for (vector<pair<osd_reqid_t, version_t> >::const_iterator j =
 466                e.extra_reqids.begin();
 467              j != e.extra_reqids.end();
 468              ++j) {
 469           extra_caller_ops.insert(make_pair(j->first, &(log.back())));
 470         }
 471       }
 472
 473       if (!applied) {
 474         skip_can_rollback_to_to_head();
 475       }
 476     }
 477
 478     void trim(
 479       CephContext* cct,
 480       eversion_t s,
 481       set<eversion_t> *trimmed);
 482
 483     ostream& print(ostream& out) const;
 484   };
 485
 486
 487 protected:
 488   //////////////////// data members ////////////////////
 489
 490   pg_missing_tracker_t missing;
 491   IndexedLog  log;
 492
 493   eversion_t dirty_to;         ///< must clear/writeout all keys <= dirty_to
 494   eversion_t dirty_from;       ///< must clear/writeout all keys >= dirty_from
 495   eversion_t writeout_from;    ///< must writout keys >= writeout_from
 496   set<eversion_t> trimmed;     ///< must clear keys in trimmed
 497   CephContext *cct;
 498   bool pg_log_debug;
 499   /// Log is clean on [dirty_to, dirty_from)
 500   bool touched_log;
 501   bool clear_divergent_priors;
 502
 503   void mark_dirty_to(eversion_t to) {
 504     if (to > dirty_to)
 505       dirty_to = to;
 506   }
 507   void mark_dirty_from(eversion_t from) {
 508     if (from < dirty_from)
 509       dirty_from = from;
 510   }
 511   void mark_writeout_from(eversion_t from) {
 512     if (from < writeout_from)
 513       writeout_from = from;
 514   }
 515 public:
 516   bool is_dirty() const {
 517     return !touched_log ||
 518       (dirty_to != eversion_t()) ||
 519       (dirty_from != eversion_t::max()) ||
 520       (writeout_from != eversion_t::max()) ||
 521       !(trimmed.empty()) ||
 522       !missing.is_clean();
 523   }
 524   void mark_log_for_rewrite() {
 525     mark_dirty_to(eversion_t::max());
 526     mark_dirty_from(eversion_t());
 527     touched_log = false;
 528   }
 529 protected:
 530
 531   /// DEBUG
 532   set<string> log_keys_debug;
 533   static void clear_after(set<string> *log_keys_debug, const string &lb) {
 534     if (!log_keys_debug)
 535       return;
 536     for (set<string>::iterator i = log_keys_debug->lower_bound(lb);
 537          i != log_keys_debug->end();
 538          log_keys_debug->erase(i++));
 539   }
 540   static void clear_up_to(set<string> *log_keys_debug, const string &ub) {
 541     if (!log_keys_debug)
 542       return;
 543     for (set<string>::iterator i = log_keys_debug->begin();
 544          i != log_keys_debug->end() && *i < ub;
 545          log_keys_debug->erase(i++));
 546   }
 547
 548   void check();
 549   void undirty() {
 550     dirty_to = eversion_t();
 551     dirty_from = eversion_t::max();
 552     touched_log = true;
 553     trimmed.clear();
 554     writeout_from = eversion_t::max();
 555     check();
 556     missing.flush();
 557   }
 558 public:
 559   // cppcheck-suppress noExplicitConstructor
 560   PGLog(CephContext *cct, DoutPrefixProvider *dpp = 0) :
 561     prefix_provider(dpp),
 562     dirty_from(eversion_t::max()),
 563     writeout_from(eversion_t::max()),
 564     cct(cct),
 565     pg_log_debug(!(cct && !(cct->_conf->osd_debug_pg_log_writeout))),
 566     touched_log(false),
 567     clear_divergent_priors(false) {}
 568
 569
 570   void reset_backfill();
 571
 572   void clear();
 573
 574   //////////////////// get or set missing ////////////////////
 575
 576   const pg_missing_tracker_t& get_missing() const { return missing; }
 577   void revise_have(hobject_t oid, eversion_t have) {
 578     missing.revise_have(oid, have);
 579   }
 580
 581   void revise_need(hobject_t oid, eversion_t need) {
 582     missing.revise_need(oid, need);
 583   }
 584
 585   void missing_add(const hobject_t& oid, eversion_t need, eversion_t have) {
 586     missing.add(oid, need, have);
 587   }
 588
 589   void missing_add_event(const pg_log_entry_t &e) {
 590     missing.add_next_event(e);
 591   }
 592
 593   //////////////////// get or set log ////////////////////
 594
 595   const IndexedLog &get_log() const { return log; }
 596
 597   const eversion_t &get_tail() const { return log.tail; }
 598
 599   void set_tail(eversion_t tail) { log.tail = tail; }
 600
 601   const eversion_t &get_head() const { return log.head; }
 602
 603   void set_head(eversion_t head) { log.head = head; }
 604
 605   void set_last_requested(version_t last_requested) {
 606     log.last_requested = last_requested;
 607   }
 608
 609   void index() { log.index(); }
 610
 611   void unindex() { log.unindex(); }
 612
 613   void add(const pg_log_entry_t& e, bool applied = true) {
 614     mark_writeout_from(e.version);
 615     log.add(e, applied);
 616   }
 617
 618   void reset_recovery_pointers() { log.reset_recovery_pointers(); }
 619
 620   static void clear_info_log(
 621     spg_t pgid,
 622     ObjectStore::Transaction *t);
 623
 624   void trim(
 625     eversion_t trim_to,
 626     pg_info_t &info);
 627
 628   void roll_forward_to(
 629     eversion_t roll_forward_to,
 630     LogEntryHandler *h) {
 631     log.roll_forward_to(
 632       roll_forward_to,
 633       h);
 634   }
 635
 636   eversion_t get_can_rollback_to() const {
 637     return log.get_can_rollback_to();
 638   }
 639
 640   void roll_forward(LogEntryHandler *h) {
 641     roll_forward_to(
 642       log.head,
 643       h);
 644   }
 645
 646   //////////////////// get or set log & missing ////////////////////
 647
 648   void reset_backfill_claim_log(const pg_log_t &o, LogEntryHandler *h) {
 649     log.trim_rollback_info_to(log.head, h);
 650     log.claim_log_and_clear_rollback_info(o);
 651     missing.clear();
 652     mark_dirty_to(eversion_t::max());
 653   }
 654
 655   void split_into(
 656       pg_t child_pgid,
 657       unsigned split_bits,
 658       PGLog *opg_log) {
 659     log.split_out_child(child_pgid, split_bits, &opg_log->log);
 660     missing.split_into(child_pgid, split_bits, &(opg_log->missing));
 661     opg_log->mark_dirty_to(eversion_t::max());
 662     mark_dirty_to(eversion_t::max());
 663   }
 664
 665   void recover_got(hobject_t oid, eversion_t v, pg_info_t &info) {
 666     if (missing.is_missing(oid, v)) {
 667       missing.got(oid, v);
 668
 669       // raise last_complete?
 670       if (missing.get_items().empty()) {
 671         log.complete_to = log.log.end();
 672         info.last_complete = info.last_update;
 673       }
 674       while (log.complete_to != log.log.end()) {
 675         if (missing.get_items().at(
 676               missing.get_rmissing().begin()->second
 677               ).need <= log.complete_to->version)
 678           break;
 679         if (info.last_complete < log.complete_to->version)
 680           info.last_complete = log.complete_to->version;
 681         ++log.complete_to;
 682       }
 683     }
 684
 685     assert(log.get_can_rollback_to() >= v);
 686   }
 687
 688   void activate_not_complete(pg_info_t &info) {
 689     log.complete_to = log.log.begin();
 690     while (log.complete_to->version <
 691            missing.get_items().at(
 692              missing.get_rmissing().begin()->second
 693              ).need)
 694       ++log.complete_to;
 695     assert(log.complete_to != log.log.end());
 696     if (log.complete_to == log.log.begin()) {
 697       info.last_complete = eversion_t();
 698     } else {
 699       --log.complete_to;
 700       info.last_complete = log.complete_to->version;
 701       ++log.complete_to;
 702     }
 703     log.last_requested = 0;
 704   }
 705
 706   void proc_replica_log(pg_info_t &oinfo,
 707                         const pg_log_t &olog,
 708                         pg_missing_t& omissing, pg_shard_t from) const;
 709
 710 protected:
 711   static void split_by_object(
 712     mempool::osd::list<pg_log_entry_t> &entries,
 713     map<hobject_t, mempool::osd::list<pg_log_entry_t>> *out_entries) {
 714     while (!entries.empty()) {
 715       mempool::osd::list<pg_log_entry_t> &out_list = (*out_entries)[entries.front().soid];
 716       out_list.splice(out_list.end(), entries, entries.begin());
 717     }
 718   }
 719
 720   /**
 721    * _merge_object_divergent_entries
 722    *
 723    * There are 5 distinct cases:
 724    * 1) There is a more recent update: in this case we assume we adjusted the
 725    *    store and missing during merge_log
 726    * 2) The first entry in the divergent sequence is a create.  This might
 727    *    either be because the object is a clone or because prior_version is
 728    *    eversion_t().  In this case the object does not exist and we must
 729    *    adjust missing and the store to match.
 730    * 3) We are currently missing the object.  In this case, we adjust the
 731    *    missing to our prior_version taking care to add a divergent_prior
 732    *    if necessary
 733    * 4) We can rollback all of the entries.  In this case, we do so using
 734    *    the rollbacker and return -- the object does not go into missing.
 735    * 5) We cannot rollback at least 1 of the entries.  In this case, we
 736    *    clear the object out of the store and add a missing entry at
 737    *    prior_version taking care to add a divergent_prior if
 738    *    necessary.
 739    */
 740   template <typename missing_type>
 741   static void _merge_object_divergent_entries(
 742     const IndexedLog &log,               ///< [in] log to merge against
 743     const hobject_t &hoid,               ///< [in] object we are merging
 744     const mempool::osd::list<pg_log_entry_t> &entries, ///< [in] entries for hoid to merge
 745     const pg_info_t &info,              ///< [in] info for merging entries
 746     eversion_t olog_can_rollback_to,     ///< [in] rollback boundary
 747     missing_type &missing,              ///< [in,out] missing to adjust, use
 748     LogEntryHandler *rollbacker,         ///< [in] optional rollbacker object
 749     const DoutPrefixProvider *dpp        ///< [in] logging provider
 750     ) {
 751     ldpp_dout(dpp, 20) << __func__ << ": merging hoid " << hoid
 752                        << " entries: " << entries << dendl;
 753
 754     if (hoid > info.last_backfill) {
 755       ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid << " after last_backfill"
 756                          << dendl;
 757       return;
 758     }
 759
 760     // entries is non-empty
 761     assert(!entries.empty());
 762     eversion_t last;
 763     for (list<pg_log_entry_t>::const_iterator i = entries.begin();
 764          i != entries.end();
 765          ++i) {
 766       // all entries are on hoid
 767       assert(i->soid == hoid);
 768       if (i != entries.begin() && i->prior_version != eversion_t()) {
 769         // in increasing order of version
 770         assert(i->version > last);
 771         // prior_version correct
 772         assert(i->prior_version == last);
 773       }
 774       last = i->version;
 775     }
 776
 777     const eversion_t prior_version = entries.begin()->prior_version;
 778     const eversion_t first_divergent_update = entries.begin()->version;
 779     const eversion_t last_divergent_update = entries.rbegin()->version;
 780     const bool object_not_in_store =
 781       !missing.is_missing(hoid) &&
 782       entries.rbegin()->is_delete();
 783     ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 784                        << " prior_version: " << prior_version
 785                        << " first_divergent_update: " << first_divergent_update
 786                        << " last_divergent_update: " << last_divergent_update
 787                        << dendl;
 788
 789     ceph::unordered_map<hobject_t, pg_log_entry_t*>::const_iterator objiter =
 790       log.objects.find(hoid);
 791     if (objiter != log.objects.end() &&
 792         objiter->second->version >= first_divergent_update) {
 793       /// Case 1)
 794       ldpp_dout(dpp, 10) << __func__ << ": more recent entry found: "
 795                          << *objiter->second << ", already merged" << dendl;
 796
 797       assert(objiter->second->version > last_divergent_update);
 798
 799       // ensure missing has been updated appropriately
 800       if (objiter->second->is_update()) {
 801         assert(missing.is_missing(hoid) &&
 802                missing.get_items().at(hoid).need == objiter->second->version);
 803       } else {
 804         assert(!missing.is_missing(hoid));
 805       }
 806       missing.revise_have(hoid, eversion_t());
 807       if (rollbacker) {
 808         if (!object_not_in_store) {
 809           rollbacker->remove(hoid);
 810         }
 811         for (auto &&i: entries) {
 812           rollbacker->trim(i);
 813         }
 814       }
 815       return;
 816     }
 817
 818     ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 819                        <<" has no more recent entries in log" << dendl;
 820     if (prior_version == eversion_t() || entries.front().is_clone()) {
 821       /// Case 2)
 822       ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 823                          << " prior_version or op type indicates creation,"
 824                          << " deleting"
 825                          << dendl;
 826       if (missing.is_missing(hoid))
 827         missing.rm(missing.get_items().find(hoid));
 828       if (rollbacker) {
 829         if (!object_not_in_store) {
 830           rollbacker->remove(hoid);
 831         }
 832         for (auto &&i: entries) {
 833           rollbacker->trim(i);
 834         }
 835       }
 836       return;
 837     }
 838
 839     if (missing.is_missing(hoid)) {
 840       /// Case 3)
 841       ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 842                          << " missing, " << missing.get_items().at(hoid)
 843                          << " adjusting" << dendl;
 844
 845       if (missing.get_items().at(hoid).have == prior_version) {
 846         ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 847                            << " missing.have is prior_version " << prior_version
 848                            << " removing from missing" << dendl;
 849         missing.rm(missing.get_items().find(hoid));
 850       } else {
 851         ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 852                            << " missing.have is " << missing.get_items().at(hoid).have
 853                            << ", adjusting" << dendl;
 854         missing.revise_need(hoid, prior_version);
 855         if (prior_version <= info.log_tail) {
 856           ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 857                              << " prior_version " << prior_version
 858                              << " <= info.log_tail "
 859                              << info.log_tail << dendl;
 860         }
 861       }
 862       if (rollbacker) {
 863         for (auto &&i: entries) {
 864           rollbacker->trim(i);
 865         }
 866       }
 867       return;
 868     }
 869
 870     ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 871                        << " must be rolled back or recovered,"
 872                        << " attempting to rollback"
 873                        << dendl;
 874     bool can_rollback = true;
 875     /// Distinguish between 4) and 5)
 876     for (list<pg_log_entry_t>::const_reverse_iterator i = entries.rbegin();
 877          i != entries.rend();
 878          ++i) {
 879       if (!i->can_rollback() || i->version <= olog_can_rollback_to) {
 880         ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid << " cannot rollback "
 881                            << *i << dendl;
 882         can_rollback = false;
 883         break;
 884       }
 885     }
 886
 887     if (can_rollback) {
 888       /// Case 4)
 889       for (list<pg_log_entry_t>::const_reverse_iterator i = entries.rbegin();
 890            i != entries.rend();
 891            ++i) {
 892         assert(i->can_rollback() && i->version > olog_can_rollback_to);
 893         ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 894                            << " rolling back " << *i << dendl;
 895         if (rollbacker)
 896           rollbacker->rollback(*i);
 897       }
 898       ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 899                          << " rolled back" << dendl;
 900       return;
 901     } else {
 902       /// Case 5)
 903       ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid << " cannot roll back, "
 904                          << "removing and adding to missing" << dendl;
 905       if (rollbacker) {
 906         if (!object_not_in_store)
 907           rollbacker->remove(hoid);
 908         for (auto &&i: entries) {
 909           rollbacker->trim(i);
 910         }
 911       }
 912       missing.add(hoid, prior_version, eversion_t());
 913       if (prior_version <= info.log_tail) {
 914         ldpp_dout(dpp, 10) << __func__ << ": hoid " << hoid
 915                            << " prior_version " << prior_version
 916                            << " <= info.log_tail "
 917                            << info.log_tail << dendl;
 918       }
 919     }
 920   }
 921
 922   /// Merge all entries using above
 923   template <typename missing_type>
 924   static void _merge_divergent_entries(
 925     const IndexedLog &log,               ///< [in] log to merge against
 926     mempool::osd::list<pg_log_entry_t> &entries,       ///< [in] entries to merge
 927     const pg_info_t &oinfo,              ///< [in] info for merging entries
 928     eversion_t olog_can_rollback_to,     ///< [in] rollback boundary
 929     missing_type &omissing,              ///< [in,out] missing to adjust, use
 930     LogEntryHandler *rollbacker,         ///< [in] optional rollbacker object
 931     const DoutPrefixProvider *dpp        ///< [in] logging provider
 932     ) {
 933     map<hobject_t, mempool::osd::list<pg_log_entry_t> > split;
 934     split_by_object(entries, &split);
 935     for (map<hobject_t, mempool::osd::list<pg_log_entry_t>>::iterator i = split.begin();
 936          i != split.end();
 937          ++i) {
 938       _merge_object_divergent_entries(
 939         log,
 940         i->first,
 941         i->second,
 942         oinfo,
 943         olog_can_rollback_to,
 944         omissing,
 945         rollbacker,
 946         dpp);
 947     }
 948   }
 949
 950   /**
 951    * Exists for use in TestPGLog for simply testing single divergent log
 952    * cases
 953    */
 954   void merge_old_entry(
 955     ObjectStore::Transaction& t,
 956     const pg_log_entry_t& oe,
 957     const pg_info_t& info,
 958     LogEntryHandler *rollbacker) {
 959     mempool::osd::list<pg_log_entry_t> entries;
 960     entries.push_back(oe);
 961     _merge_object_divergent_entries(
 962       log,
 963       oe.soid,
 964       entries,
 965       info,
 966       log.get_can_rollback_to(),
 967       missing,
 968       rollbacker,
 969       this);
 970   }
 971 public:
 972   void rewind_divergent_log(eversion_t newhead,
 973                             pg_info_t &info,
 974                             LogEntryHandler *rollbacker,
 975                             bool &dirty_info,
 976                             bool &dirty_big_info);
 977
 978   void merge_log(pg_info_t &oinfo,
 979                  pg_log_t &olog,
 980                  pg_shard_t from,
 981                  pg_info_t &info, LogEntryHandler *rollbacker,
 982                  bool &dirty_info, bool &dirty_big_info);
 983
 984   template <typename missing_type>
 985   static bool append_log_entries_update_missing(
 986     const hobject_t &last_backfill,
 987     bool last_backfill_bitwise,
 988     const mempool::osd::list<pg_log_entry_t> &entries,
 989     bool maintain_rollback,
 990     IndexedLog *log,
 991     missing_type &missing,
 992     LogEntryHandler *rollbacker,
 993     const DoutPrefixProvider *dpp) {
 994     bool invalidate_stats = false;
 995     if (log && !entries.empty()) {
 996       assert(log->head < entries.begin()->version);
 997     }
 998     for (list<pg_log_entry_t>::const_iterator p = entries.begin();
 999          p != entries.end();
1000          ++p) {
1001       invalidate_stats = invalidate_stats || !p->is_error();
1002       if (log) {
1003         ldpp_dout(dpp, 20) << "update missing, append " << *p << dendl;
1004         log->add(*p);
1005       }
1006       if (p->soid <= last_backfill &&
1007           !p->is_error()) {
1008         missing.add_next_event(*p);
1009         if (rollbacker) {
1010           // hack to match PG::mark_all_unfound_lost
1011           if (maintain_rollback && p->is_lost_delete() && p->can_rollback()) {
1012             rollbacker->try_stash(p->soid, p->version.version);
1013           } else if (p->is_delete()) {
1014             rollbacker->remove(p->soid);
1015           }
1016         }
1017       }
1018     }
1019     return invalidate_stats;
1020   }
1021   bool append_new_log_entries(
1022     const hobject_t &last_backfill,
1023     bool last_backfill_bitwise,
1024     const mempool::osd::list<pg_log_entry_t> &entries,
1025     LogEntryHandler *rollbacker) {
1026     bool invalidate_stats = append_log_entries_update_missing(
1027       last_backfill,
1028       last_backfill_bitwise,
1029       entries,
1030       true,
1031       &log,
1032       missing,
1033       rollbacker,
1034       this);
1035     if (!entries.empty()) {
1036       mark_writeout_from(entries.begin()->version);
1037     }
1038     return invalidate_stats;
1039   }
1040
1041   void write_log_and_missing(ObjectStore::Transaction& t,
1042                  map<string,bufferlist> *km,
1043                  const coll_t& coll,
1044                  const ghobject_t &log_oid,
1045                  bool require_rollback);
1046
1047   static void write_log_and_missing_wo_missing(
1048     ObjectStore::Transaction& t,
1049     map<string,bufferlist>* km,
1050     pg_log_t &log,
1051     const coll_t& coll,
1052     const ghobject_t &log_oid, map<eversion_t, hobject_t> &divergent_priors,
1053     bool require_rollback);
1054
1055   static void write_log_and_missing(
1056     ObjectStore::Transaction& t,
1057     map<string,bufferlist>* km,
1058     pg_log_t &log,
1059     const coll_t& coll,
1060     const ghobject_t &log_oid,
1061     const pg_missing_tracker_t &missing,
1062     bool require_rollback);
1063
1064   static void _write_log_and_missing_wo_missing(
1065     ObjectStore::Transaction& t,
1066     map<string,bufferlist>* km,
1067     pg_log_t &log,
1068     const coll_t& coll, const ghobject_t &log_oid,
1069     map<eversion_t, hobject_t> &divergent_priors,
1070     eversion_t dirty_to,
1071     eversion_t dirty_from,
1072     eversion_t writeout_from,
1073     const set<eversion_t> &trimmed,
1074     bool dirty_divergent_priors,
1075     bool touch_log,
1076     bool require_rollback,
1077     set<string> *log_keys_debug
1078     );
1079
1080   static void _write_log_and_missing(
1081     ObjectStore::Transaction& t,
1082     map<string,bufferlist>* km,
1083     pg_log_t &log,
1084     const coll_t& coll, const ghobject_t &log_oid,
1085     eversion_t dirty_to,
1086     eversion_t dirty_from,
1087     eversion_t writeout_from,
1088     const set<eversion_t> &trimmed,
1089     const pg_missing_tracker_t &missing,
1090     bool touch_log,
1091     bool require_rollback,
1092     bool clear_divergent_priors,
1093     set<string> *log_keys_debug
1094     );
1095
1096   void read_log_and_missing(
1097     ObjectStore *store, coll_t pg_coll,
1098     coll_t log_coll, ghobject_t log_oid,
1099     const pg_info_t &info,
1100     ostringstream &oss,
1101     bool tolerate_divergent_missing_log,
1102     bool debug_verify_stored_missing = false
1103     ) {
1104     return read_log_and_missing(
1105       store, pg_coll, log_coll, log_oid, info,
1106       log, missing, oss,
1107       tolerate_divergent_missing_log,
1108       &clear_divergent_priors,
1109       this,
1110       (pg_log_debug ? &log_keys_debug : 0),
1111       debug_verify_stored_missing);
1112   }
1113
1114   template <typename missing_type>
1115   static void read_log_and_missing(ObjectStore *store, coll_t pg_coll,
1116     coll_t log_coll, ghobject_t log_oid,
1117     const pg_info_t &info,
1118     IndexedLog &log,
1119     missing_type &missing, ostringstream &oss,
1120     bool tolerate_divergent_missing_log,
1121     bool *clear_divergent_priors = NULL,
1122     const DoutPrefixProvider *dpp = NULL,
1123     set<string> *log_keys_debug = 0,
1124     bool debug_verify_stored_missing = false
1125     ) {
1126     ldpp_dout(dpp, 20) << "read_log_and_missing coll " << pg_coll
1127                        << " log_oid " << log_oid << dendl;
1128
1129     // legacy?
1130     struct stat st;
1131     int r = store->stat(log_coll, log_oid, &st);
1132     assert(r == 0);
1133     assert(st.st_size == 0);
1134
1135     // will get overridden below if it had been recorded
1136     eversion_t on_disk_can_rollback_to = info.last_update;
1137     eversion_t on_disk_rollback_info_trimmed_to = eversion_t();
1138     ObjectMap::ObjectMapIterator p = store->get_omap_iterator(log_coll, log_oid);
1139     map<eversion_t, hobject_t> divergent_priors;
1140     bool has_divergent_priors = false;
1141     list<pg_log_entry_t> entries;
1142     if (p) {
1143       for (p->seek_to_first(); p->valid() ; p->next(false)) {
1144         // non-log pgmeta_oid keys are prefixed with _; skip those
1145         if (p->key()[0] == '_')
1146           continue;
1147         bufferlist bl = p->value();//Copy bufferlist before creating iterator
1148         bufferlist::iterator bp = bl.begin();
1149         if (p->key() == "divergent_priors") {
1150           ::decode(divergent_priors, bp);
1151           ldpp_dout(dpp, 20) << "read_log_and_missing " << divergent_priors.size()
1152                              << " divergent_priors" << dendl;
1153           has_divergent_priors = true;
1154           debug_verify_stored_missing = false;
1155         } else if (p->key() == "can_rollback_to") {
1156           ::decode(on_disk_can_rollback_to, bp);
1157         } else if (p->key() == "rollback_info_trimmed_to") {
1158           ::decode(on_disk_rollback_info_trimmed_to, bp);
1159         } else if (p->key().substr(0, 7) == string("missing")) {
1160           pair<hobject_t, pg_missing_item> p;
1161           ::decode(p, bp);
1162           missing.add(p.first, p.second.need, p.second.have);
1163         } else {
1164           pg_log_entry_t e;
1165           e.decode_with_checksum(bp);
1166           ldpp_dout(dpp, 20) << "read_log_and_missing " << e << dendl;
1167           if (!entries.empty()) {
1168             pg_log_entry_t last_e(entries.back());
1169             assert(last_e.version.version < e.version.version);
1170             assert(last_e.version.epoch <= e.version.epoch);
1171           }
1172           entries.push_back(e);
1173           if (log_keys_debug)
1174             log_keys_debug->insert(e.get_key_name());
1175         }
1176       }
1177     }
1178     log = IndexedLog(
1179       info.last_update,
1180       info.log_tail,
1181       on_disk_can_rollback_to,
1182       on_disk_rollback_info_trimmed_to,
1183       std::move(entries));
1184
1185     if (has_divergent_priors || debug_verify_stored_missing) {
1186       // build missing
1187       if (debug_verify_stored_missing || info.last_complete < info.last_update) {
1188         ldpp_dout(dpp, 10) << "read_log_and_missing checking for missing items over interval ("
1189                            << info.last_complete
1190                            << "," << info.last_update << "]" << dendl;
1191
1192         set<hobject_t> did;
1193         set<hobject_t> checked;
1194         set<hobject_t> skipped;
1195         for (list<pg_log_entry_t>::reverse_iterator i = log.log.rbegin();
1196              i != log.log.rend();
1197              ++i) {
1198           if (!debug_verify_stored_missing && i->version <= info.last_complete) break;
1199           if (i->soid > info.last_backfill)
1200             continue;
1201           if (i->is_error())
1202             continue;
1203           if (did.count(i->soid)) continue;
1204           did.insert(i->soid);
1205
1206           if (i->is_delete()) continue;
1207
1208           bufferlist bv;
1209           int r = store->getattr(
1210             pg_coll,
1211             ghobject_t(i->soid, ghobject_t::NO_GEN, info.pgid.shard),
1212             OI_ATTR,
1213             bv);
1214           if (r >= 0) {
1215             object_info_t oi(bv);
1216             if (oi.version < i->version) {
1217               ldpp_dout(dpp, 15) << "read_log_and_missing  missing " << *i
1218                                  << " (have " << oi.version << ")" << dendl;
1219               if (debug_verify_stored_missing) {
1220                 auto miter = missing.get_items().find(i->soid);
1221                 assert(miter != missing.get_items().end());
1222                 assert(miter->second.need == i->version);
1223                 assert(miter->second.have == oi.version);
1224                 checked.insert(i->soid);
1225               } else {
1226                 missing.add(i->soid, i->version, oi.version);
1227               }
1228             }
1229           } else {
1230             ldpp_dout(dpp, 15) << "read_log_and_missing  missing " << *i << dendl;
1231             if (debug_verify_stored_missing) {
1232               auto miter = missing.get_items().find(i->soid);
1233               assert(miter != missing.get_items().end());
1234               assert(miter->second.need == i->version);
1235               assert(miter->second.have == eversion_t());
1236               checked.insert(i->soid);
1237             } else {
1238               missing.add(i->soid, i->version, eversion_t());
1239             }
1240           }
1241         }
1242         if (debug_verify_stored_missing) {
1243           for (auto &&i: missing.get_items()) {
1244             if (checked.count(i.first))
1245               continue;
1246             if (i.second.need > log.tail ||
1247               i.first > info.last_backfill) {
1248               ldpp_dout(dpp, -1) << __func__ << ": invalid missing set entry found "
1249                                  << i.first
1250                                  << dendl;
1251               assert(0 == "invalid missing set entry found");
1252             }
1253             bufferlist bv;
1254             int r = store->getattr(
1255               pg_coll,
1256               ghobject_t(i.first, ghobject_t::NO_GEN, info.pgid.shard),
1257               OI_ATTR,
1258               bv);
1259             if (r >= 0) {
1260               object_info_t oi(bv);
1261               assert(oi.version == i.second.have);
1262             } else {
1263               assert(eversion_t() == i.second.have);
1264             }
1265           }
1266         } else {
1267           assert(has_divergent_priors);
1268           for (map<eversion_t, hobject_t>::reverse_iterator i =
1269                  divergent_priors.rbegin();
1270                i != divergent_priors.rend();
1271                ++i) {
1272             if (i->first <= info.last_complete) break;
1273             if (i->second > info.last_backfill)
1274               continue;
1275             if (did.count(i->second)) continue;
1276             did.insert(i->second);
1277             bufferlist bv;
1278             int r = store->getattr(
1279               pg_coll,
1280               ghobject_t(i->second, ghobject_t::NO_GEN, info.pgid.shard),
1281               OI_ATTR,
1282               bv);
1283             if (r >= 0) {
1284               object_info_t oi(bv);
1285               /**
1286                  * 1) we see this entry in the divergent priors mapping
1287                  * 2) we didn't see an entry for this object in the log
1288                  *
1289                  * From 1 & 2 we know that either the object does not exist
1290                  * or it is at the version specified in the divergent_priors
1291                  * map since the object would have been deleted atomically
1292                  * with the addition of the divergent_priors entry, an older
1293                  * version would not have been recovered, and a newer version
1294                  * would show up in the log above.
1295                  */
1296                 /**
1297                  * Unfortunately the assessment above is incorrect because of
1298                  * http://tracker.ceph.com/issues/17916 (we were incorrectly
1299                  * not removing the divergent_priors set from disk state!),
1300                  * so let's check that.
1301                  */
1302               if (oi.version > i->first && tolerate_divergent_missing_log) {
1303                 ldpp_dout(dpp, 0) << "read_log divergent_priors entry (" << *i
1304                                   << ") inconsistent with disk state (" <<  oi
1305                                   << "), assuming it is tracker.ceph.com/issues/17916"
1306                                   << dendl;
1307               } else {
1308                 assert(oi.version == i->first);
1309               }
1310             } else {
1311               ldpp_dout(dpp, 15) << "read_log_and_missing  missing " << *i << dendl;
1312               missing.add(i->second, i->first, eversion_t());
1313             }
1314           }
1315         }
1316         if (clear_divergent_priors)
1317           (*clear_divergent_priors) = true;
1318       }
1319     }
1320
1321     if (!has_divergent_priors) {
1322       if (clear_divergent_priors)
1323         (*clear_divergent_priors) = false;
1324       missing.flush();
1325     }
1326     ldpp_dout(dpp, 10) << "read_log_and_missing done" << dendl;
1327   }
1328 };
1329
1330 #endif // CEPH_PG_LOG_H