/*- * See the file LICENSE for redistribution information. * * Copyright (c) 2001-2004 * Sleepycat Software. All rights reserved. * * $Id: rep_record.c,v 1.1.1.1 2005/06/24 22:42:42 ca Exp $ */ #include "db_config.h" #ifndef NO_SYSTEM_INCLUDES #if TIME_WITH_SYS_TIME #include #include #else #if HAVE_SYS_TIME_H #include #else #include #endif #endif #include #include #endif #include "db_int.h" #include "dbinc/db_page.h" #include "dbinc/db_shash.h" #include "dbinc/db_am.h" #include "dbinc/lock.h" #include "dbinc/log.h" #include "dbinc/mp.h" #include "dbinc/txn.h" static int __rep_apply __P((DB_ENV *, REP_CONTROL *, DBT *, DB_LSN *, int *)); static int __rep_collect_txn __P((DB_ENV *, DB_LSN *, LSN_COLLECTION *)); static int __rep_do_ckp __P((DB_ENV *, DBT *, REP_CONTROL *)); static int __rep_dorecovery __P((DB_ENV *, DB_LSN *, DB_LSN *)); static int __rep_getnext __P((DB_ENV *)); static int __rep_lsn_cmp __P((const void *, const void *)); static int __rep_newfile __P((DB_ENV *, REP_CONTROL *, DB_LSN *)); static int __rep_process_rec __P((DB_ENV *, REP_CONTROL *, DBT *, u_int32_t *, DB_LSN *)); static int __rep_remfirst __P((DB_ENV *, DBT *, DBT *)); static int __rep_resend_req __P((DB_ENV *, int)); static int __rep_verify_match __P((DB_ENV *, DB_LSN *, time_t)); /* Used to consistently designate which messages ought to be received where. */ #define MASTER_ONLY(rep, rp) do { \ if (!F_ISSET(rep, REP_F_MASTER)) { \ RPRINT(dbenv, rep, \ (dbenv, &mb, "Master record received on client")); \ REP_PRINT_MESSAGE(dbenv, \ *eidp, rp, "rep_process_message"); \ ret = EINVAL; \ goto errlock; \ } \ } while (0) #define CLIENT_ONLY(rep, rp) do { \ if (!F_ISSET(rep, REP_F_CLIENT)) { \ RPRINT(dbenv, rep, \ (dbenv, &mb, "Client record received on master")); \ REP_PRINT_MESSAGE(dbenv, \ *eidp, rp, "rep_process_message"); \ (void)__rep_send_message(dbenv, \ DB_EID_BROADCAST, REP_DUPMASTER, NULL, NULL, 0); \ ret = DB_REP_DUPMASTER; \ goto errlock; \ } \ } while (0) #define MASTER_CHECK(dbenv, eid, rep) do { \ if (rep->master_id == DB_EID_INVALID) { \ RPRINT(dbenv, rep, (dbenv, &mb, \ "Received record from %d, master is INVALID", eid));\ ret = 0; \ (void)__rep_send_message(dbenv, \ DB_EID_BROADCAST, REP_MASTER_REQ, NULL, NULL, 0); \ goto errlock; \ } \ if (eid != rep->master_id) { \ __db_err(dbenv, \ "Received master record from %d, master is %d", \ eid, rep->master_id); \ ret = EINVAL; \ goto errlock; \ } \ } while (0) #define MASTER_UPDATE(dbenv, renv) do { \ MUTEX_LOCK((dbenv), &(renv)->mutex); \ F_SET((renv), DB_REGENV_REPLOCKED); \ (void)time(&(renv)->op_timestamp); \ MUTEX_UNLOCK((dbenv), &(renv)->mutex); \ } while (0) #define ANYSITE(rep) /* * __rep_process_message -- * * This routine takes an incoming message and processes it. * * control: contains the control fields from the record * rec: contains the actual record * eidp: contains the machine id of the sender of the message; * in the case of a DB_NEWMASTER message, returns the eid * of the new master. * ret_lsnp: On DB_REP_ISPERM and DB_REP_NOTPERM returns, contains the * lsn of the maximum permanent or current not permanent log record * (respectively). * * PUBLIC: int __rep_process_message __P((DB_ENV *, DBT *, DBT *, int *, * PUBLIC: DB_LSN *)); */ int __rep_process_message(dbenv, control, rec, eidp, ret_lsnp) DB_ENV *dbenv; DBT *control, *rec; int *eidp; DB_LSN *ret_lsnp; { DB_LOG *dblp; DB_LOGC *logc; DB_LSN endlsn, lsn, oldfilelsn; DB_REP *db_rep; DBT *d, data_dbt, mylog; LOG *lp; REGENV *renv; REGINFO *infop; REP *rep; REP_CONTROL *rp; REP_VOTE_INFO *vi; u_int32_t bytes, egen, flags, gen, gbytes, rectype, type; int check_limit, cmp, done, do_req, is_dup; int master, match, old, recovering, ret, t_ret; time_t savetime; #ifdef DIAGNOSTIC DB_MSGBUF mb; #endif PANIC_CHECK(dbenv); ENV_REQUIRES_CONFIG(dbenv, dbenv->rep_handle, "rep_process_message", DB_INIT_REP); /* Control argument must be non-Null. */ if (control == NULL || control->size == 0) { __db_err(dbenv, "DB_ENV->rep_process_message: control argument must be specified"); return (EINVAL); } if (!IS_REP_MASTER(dbenv) && !IS_REP_CLIENT(dbenv)) { __db_err(dbenv, "Environment not configured as replication master or client"); return (EINVAL); } ret = 0; db_rep = dbenv->rep_handle; rep = db_rep->region; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; infop = dbenv->reginfo; renv = infop->primary; rp = (REP_CONTROL *)control->data; if (ret_lsnp != NULL) ZERO_LSN(*ret_lsnp); /* * Acquire the replication lock. */ MUTEX_LOCK(dbenv, db_rep->rep_mutexp); if (rep->start_th != 0) { /* * If we're racing with a thread in rep_start, then * just ignore the message and return. */ RPRINT(dbenv, rep, (dbenv, &mb, "Racing rep_start, ignore message.")); MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); goto out; } rep->msg_th++; gen = rep->gen; recovering = rep->in_recovery || F_ISSET(rep, REP_F_RECOVER_MASK); savetime = renv->rep_timestamp; rep->stat.st_msgs_processed++; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); REP_PRINT_MESSAGE(dbenv, *eidp, rp, "rep_process_message"); /* Complain if we see an improper version number. */ if (rp->rep_version != DB_REPVERSION) { __db_err(dbenv, "unexpected replication message version %lu, expected %d", (u_long)rp->rep_version, DB_REPVERSION); ret = EINVAL; goto errlock; } if (rp->log_version != DB_LOGVERSION) { __db_err(dbenv, "unexpected log record version %lu, expected %d", (u_long)rp->log_version, DB_LOGVERSION); ret = EINVAL; goto errlock; } /* * Check for generation number matching. Ignore any old messages * except requests that are indicative of a new client that needs * to get in sync. */ if (rp->gen < gen && rp->rectype != REP_ALIVE_REQ && rp->rectype != REP_NEWCLIENT && rp->rectype != REP_MASTER_REQ && rp->rectype != REP_DUPMASTER) { /* * We don't hold the rep mutex, and could miscount if we race. */ rep->stat.st_msgs_badgen++; goto errlock; } if (rp->gen > gen) { /* * If I am a master and am out of date with a lower generation * number, I am in bad shape and should downgrade. */ if (F_ISSET(rep, REP_F_MASTER)) { rep->stat.st_dupmasters++; ret = DB_REP_DUPMASTER; if (rp->rectype != REP_DUPMASTER) (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_DUPMASTER, NULL, NULL, 0); goto errlock; } /* * I am a client and am out of date. If this is an election, * or a response from the first site I contacted, then I can * accept the generation number and participate in future * elections and communication. Otherwise, I need to hear about * a new master and sync up. */ if (rp->rectype == REP_ALIVE || rp->rectype == REP_VOTE1 || rp->rectype == REP_VOTE2) { MUTEX_LOCK(dbenv, db_rep->rep_mutexp); RPRINT(dbenv, rep, (dbenv, &mb, "Updating gen from %lu to %lu", (u_long)gen, (u_long)rp->gen)); rep->master_id = DB_EID_INVALID; gen = rep->gen = rp->gen; /* * Updating of egen will happen when we process the * message below for each message type. */ MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); if (rp->rectype == REP_ALIVE) (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_MASTER_REQ, NULL, NULL, 0); } else if (rp->rectype != REP_NEWMASTER) { (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_MASTER_REQ, NULL, NULL, 0); goto errlock; } /* * If you get here, then you're a client and either you're * in an election or you have a NEWMASTER or an ALIVE message * whose processing will do the right thing below. */ } /* * We need to check if we're in recovery and if we are * then we need to ignore any messages except VERIFY*, VOTE*, * NEW* and ALIVE_REQ, or backup related messages: UPDATE*, * PAGE* and FILE*. We need to also accept LOG messages * if we're copying the log for recovery/backup. */ if (recovering) { switch (rp->rectype) { case REP_VERIFY: MUTEX_LOCK(dbenv, db_rep->db_mutexp); cmp = log_compare(&lp->verify_lsn, &rp->lsn); MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); if (cmp != 0) goto skip; break; case REP_NEWFILE: case REP_LOG: case REP_LOG_MORE: if (!F_ISSET(rep, REP_F_RECOVER_LOG)) goto skip; /* * If we're recovering the log we only want * log records that are in the range we need * to recover. Otherwise we can end up storing * a huge number of "new" records, only to * truncate the temp database later after we * run recovery. */ if (log_compare(&rp->lsn, &rep->last_lsn) > 0) goto skip; break; case REP_ALIVE: case REP_ALIVE_REQ: case REP_DUPMASTER: case REP_FILE_FAIL: case REP_NEWCLIENT: case REP_NEWMASTER: case REP_NEWSITE: case REP_PAGE: case REP_PAGE_FAIL: case REP_PAGE_MORE: case REP_PAGE_REQ: case REP_UPDATE: case REP_UPDATE_REQ: case REP_VERIFY_FAIL: case REP_VOTE1: case REP_VOTE2: break; default: skip: /* Check for need to retransmit. */ /* Not holding rep_mutex, may miscount */ rep->stat.st_msgs_recover++; MUTEX_LOCK(dbenv, db_rep->db_mutexp); do_req = __rep_check_doreq(dbenv, rep); MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); if (do_req) { /* * Don't respond to a MASTER_REQ with * a MASTER_REQ. */ if (rep->master_id == DB_EID_INVALID && rp->rectype != REP_MASTER_REQ) (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_MASTER_REQ, NULL, NULL, 0); else if (*eidp == rep->master_id) ret = __rep_resend_req(dbenv, *eidp); } goto errlock; } } switch (rp->rectype) { case REP_ALIVE: ANYSITE(rep); egen = *(u_int32_t *)rec->data; MUTEX_LOCK(dbenv, db_rep->rep_mutexp); RPRINT(dbenv, rep, (dbenv, &mb, "Received ALIVE egen of %lu, mine %lu", (u_long)egen, (u_long)rep->egen)); if (egen > rep->egen) { /* * We're changing egen, need to clear out any old * election information. */ __rep_elect_done(dbenv, rep); rep->egen = egen; } MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); break; case REP_ALIVE_REQ: ANYSITE(rep); dblp = dbenv->lg_handle; R_LOCK(dbenv, &dblp->reginfo); lsn = ((LOG *)dblp->reginfo.primary)->lsn; R_UNLOCK(dbenv, &dblp->reginfo); MUTEX_LOCK(dbenv, db_rep->rep_mutexp); egen = rep->egen; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); data_dbt.data = &egen; data_dbt.size = sizeof(egen); (void)__rep_send_message(dbenv, *eidp, REP_ALIVE, &lsn, &data_dbt, 0); goto errlock; case REP_DUPMASTER: if (F_ISSET(rep, REP_F_MASTER)) ret = DB_REP_DUPMASTER; goto errlock; case REP_ALL_REQ: MASTER_ONLY(rep, rp); gbytes = bytes = 0; MUTEX_LOCK(dbenv, db_rep->rep_mutexp); gbytes = rep->gbytes; bytes = rep->bytes; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); check_limit = gbytes != 0 || bytes != 0; if ((ret = __log_cursor(dbenv, &logc)) != 0) goto errlock; memset(&data_dbt, 0, sizeof(data_dbt)); oldfilelsn = lsn = rp->lsn; type = REP_LOG; flags = IS_ZERO_LSN(rp->lsn) || IS_INIT_LSN(rp->lsn) ? DB_FIRST : DB_SET; for (ret = __log_c_get(logc, &lsn, &data_dbt, flags); ret == 0 && type == REP_LOG; ret = __log_c_get(logc, &lsn, &data_dbt, DB_NEXT)) { /* * When a log file changes, we'll have a real log * record with some lsn [n][m], and we'll also want * to send a NEWFILE message with lsn [n-1][MAX]. */ if (lsn.file != oldfilelsn.file) (void)__rep_send_message(dbenv, *eidp, REP_NEWFILE, &oldfilelsn, NULL, 0); if (check_limit) { /* * data_dbt.size is only the size of the log * record; it doesn't count the size of the * control structure. Factor that in as well * so we're not off by a lot if our log records * are small. */ while (bytes < data_dbt.size + sizeof(REP_CONTROL)) { if (gbytes > 0) { bytes += GIGABYTE; --gbytes; continue; } /* * We don't hold the rep mutex, * and may miscount. */ rep->stat.st_nthrottles++; type = REP_LOG_MORE; goto send; } bytes -= (data_dbt.size + sizeof(REP_CONTROL)); } send: if (__rep_send_message(dbenv, *eidp, type, &lsn, &data_dbt, DB_LOG_RESEND) != 0) break; /* * If we are about to change files, then we'll need the * last LSN in the previous file. Save it here. */ oldfilelsn = lsn; oldfilelsn.offset += logc->c_len; } if (ret == DB_NOTFOUND) ret = 0; if ((t_ret = __log_c_close(logc)) != 0 && ret == 0) ret = t_ret; goto errlock; #ifdef NOTYET case REP_FILE: /* TODO */ CLIENT_ONLY(rep, rp); MASTER_CHECK(dbenv, *eidp, rep); break; case REP_FILE_REQ: MASTER_ONLY(rep, rp); ret = __rep_send_file(dbenv, rec, *eidp); goto errlock; #endif case REP_FILE_FAIL: CLIENT_ONLY(rep, rp); MASTER_CHECK(dbenv, *eidp, rep); /* * XXX */ break; case REP_LOG: case REP_LOG_MORE: CLIENT_ONLY(rep, rp); MASTER_CHECK(dbenv, *eidp, rep); is_dup = 0; ret = __rep_apply(dbenv, rp, rec, ret_lsnp, &is_dup); switch (ret) { /* * We're in an internal backup and we've gotten * all the log we need to run recovery. Do so now. */ case DB_REP_LOGREADY: if ((ret = __log_flush(dbenv, NULL)) != 0) goto errlock; if ((ret = __rep_verify_match(dbenv, &rep->last_lsn, savetime)) == 0) { MUTEX_LOCK(dbenv, db_rep->rep_mutexp); ZERO_LSN(rep->first_lsn); ZERO_LSN(rep->last_lsn); F_CLR(rep, REP_F_RECOVER_LOG); MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); } break; /* * If we get any of the "normal" returns, we only process * LOG_MORE if this is not a duplicate record. If the * record is a duplicate we don't want to handle LOG_MORE * and request a multiple data stream (or trigger internal * initialization) since this could be a very old record * that no longer exists on the master. */ case DB_REP_ISPERM: case DB_REP_NOTPERM: case 0: if (is_dup) goto errlock; else break; /* * Any other return (errors), we're done. */ default: goto errlock; } if (rp->rectype == REP_LOG_MORE) { MUTEX_LOCK(dbenv, db_rep->rep_mutexp); master = rep->master_id; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); R_LOCK(dbenv, &dblp->reginfo); lsn = lp->lsn; R_UNLOCK(dbenv, &dblp->reginfo); /* * If the master_id is invalid, this means that since * the last record was sent, somebody declared an * election and we may not have a master to request * things of. * * This is not an error; when we find a new master, * we'll re-negotiate where the end of the log is and * try to bring ourselves up to date again anyway. */ MUTEX_LOCK(dbenv, db_rep->db_mutexp); if (master == DB_EID_INVALID) ret = 0; /* * If we've asked for a bunch of records, it could * either be from a LOG_REQ or ALL_REQ. If we're * waiting for a gap to be filled, call loggap_req, * otherwise use ALL_REQ again. */ else if (IS_ZERO_LSN(lp->waiting_lsn)) { MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); if (__rep_send_message(dbenv, master, REP_ALL_REQ, &lsn, NULL, 0) != 0) break; } else { __rep_loggap_req(dbenv, rep, &lsn, 1); MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); } } goto errlock; case REP_LOG_REQ: MASTER_ONLY(rep, rp); if (rec != NULL && rec->size != 0) { RPRINT(dbenv, rep, (dbenv, &mb, "[%lu][%lu]: LOG_REQ max lsn: [%lu][%lu]", (u_long) rp->lsn.file, (u_long)rp->lsn.offset, (u_long)((DB_LSN *)rec->data)->file, (u_long)((DB_LSN *)rec->data)->offset)); } /* * There are three different cases here. * 1. We asked for a particular LSN and got it. * 2. We asked for an LSN and it's not found because it is * beyond the end of a log file and we need a NEWFILE msg. * and then the record that was requested. * 3. We asked for an LSN and it simply doesn't exist, but * doesn't meet any of those other criteria, in which case * it's an error (that should never happen). * If we have a valid LSN and the request has a data_dbt with * it, then we need to send all records up to the LSN in the * data dbt. */ oldfilelsn = lsn = rp->lsn; if ((ret = __log_cursor(dbenv, &logc)) != 0) goto errlock; memset(&data_dbt, 0, sizeof(data_dbt)); ret = __log_c_get(logc, &lsn, &data_dbt, DB_SET); if (ret == 0) /* Case 1 */ (void)__rep_send_message(dbenv, *eidp, REP_LOG, &lsn, &data_dbt, DB_LOG_RESEND); else if (ret == DB_NOTFOUND) { R_LOCK(dbenv, &dblp->reginfo); endlsn = lp->lsn; R_UNLOCK(dbenv, &dblp->reginfo); if (endlsn.file > lsn.file) { /* * Case 2: * Need to find the LSN of the last record in * file lsn.file so that we can send it with * the NEWFILE call. In order to do that, we * need to try to get {lsn.file + 1, 0} and * then backup. */ endlsn.file = lsn.file + 1; endlsn.offset = 0; if ((ret = __log_c_get(logc, &endlsn, &data_dbt, DB_SET)) != 0 || (ret = __log_c_get(logc, &endlsn, &data_dbt, DB_PREV)) != 0) { RPRINT(dbenv, rep, (dbenv, &mb, "Unable to get prev of [%lu][%lu]", (u_long)lsn.file, (u_long)lsn.offset)); /* * We want to push the error back * to the client so that the client * does an internal backup. The * client asked for a log record * we no longer have and it is * outdated. * XXX - This could be optimized by * having the master perform and * send a REP_UPDATE message. We * currently want the client to set * up its 'update' state prior to * requesting REP_UPDATE_REQ. */ ret = 0; (void)__rep_send_message(dbenv, *eidp, REP_VERIFY_FAIL, &rp->lsn, NULL, 0); } else { endlsn.offset += logc->c_len; (void)__rep_send_message(dbenv, *eidp, REP_NEWFILE, &endlsn, NULL, 0); } } else { /* Case 3 */ __db_err(dbenv, "Request for LSN [%lu][%lu] fails", (u_long)lsn.file, (u_long)lsn.offset); DB_ASSERT(0); ret = EINVAL; } } /* * If the user requested a gap, send the whole thing, * while observing the limits from set_rep_limit. */ MUTEX_LOCK(dbenv, db_rep->rep_mutexp); gbytes = rep->gbytes; bytes = rep->bytes; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); check_limit = gbytes != 0 || bytes != 0; type = REP_LOG; while (ret == 0 && rec != NULL && rec->size != 0 && type == REP_LOG) { if ((ret = __log_c_get(logc, &lsn, &data_dbt, DB_NEXT)) != 0) { if (ret == DB_NOTFOUND) ret = 0; break; } if (log_compare(&lsn, (DB_LSN *)rec->data) >= 0) break; /* * When a log file changes, we'll have a real log * record with some lsn [n][m], and we'll also want * to send a NEWFILE message with lsn [n-1][MAX]. */ if (lsn.file != oldfilelsn.file) (void)__rep_send_message(dbenv, *eidp, REP_NEWFILE, &oldfilelsn, NULL, 0); if (check_limit) { /* * data_dbt.size is only the size of the log * record; it doesn't count the size of the * control structure. Factor that in as well * so we're not off by a lot if our log records * are small. */ while (bytes < data_dbt.size + sizeof(REP_CONTROL)) { if (gbytes > 0) { bytes += GIGABYTE; --gbytes; continue; } /* * We don't hold the rep mutex, * and may miscount. */ rep->stat.st_nthrottles++; type = REP_LOG_MORE; goto send1; } bytes -= (data_dbt.size + sizeof(REP_CONTROL)); } send1: if (__rep_send_message(dbenv, *eidp, type, &lsn, &data_dbt, DB_LOG_RESEND) != 0) break; /* * If we are about to change files, then we'll need the * last LSN in the previous file. Save it here. */ oldfilelsn = lsn; oldfilelsn.offset += logc->c_len; } if ((t_ret = __log_c_close(logc)) != 0 && ret == 0) ret = t_ret; goto errlock; case REP_NEWSITE: /* We don't hold the rep mutex, and may miscount. */ rep->stat.st_newsites++; /* This is a rebroadcast; simply tell the application. */ if (F_ISSET(rep, REP_F_MASTER)) { dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; R_LOCK(dbenv, &dblp->reginfo); lsn = lp->lsn; R_UNLOCK(dbenv, &dblp->reginfo); (void)__rep_send_message(dbenv, *eidp, REP_NEWMASTER, &lsn, NULL, 0); } ret = DB_REP_NEWSITE; goto errlock; case REP_NEWCLIENT: /* * This message was received and should have resulted in the * application entering the machine ID in its machine table. * We respond to this with an ALIVE to send relevant information * to the new client (if we are a master, we'll send a * NEWMASTER, so we only need to send the ALIVE if we're a * client). But first, broadcast the new client's record to * all the clients. */ (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_NEWSITE, &rp->lsn, rec, 0); ret = DB_REP_NEWSITE; if (F_ISSET(rep, REP_F_CLIENT)) { MUTEX_LOCK(dbenv, db_rep->rep_mutexp); egen = rep->egen; if (*eidp == rep->master_id) rep->master_id = DB_EID_INVALID; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); data_dbt.data = &egen; data_dbt.size = sizeof(egen); (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_ALIVE, &rp->lsn, &data_dbt, 0); goto errlock; } /* FALLTHROUGH */ case REP_MASTER_REQ: if (F_ISSET(rep, REP_F_MASTER)) { R_LOCK(dbenv, &dblp->reginfo); lsn = lp->lsn; R_UNLOCK(dbenv, &dblp->reginfo); (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_NEWMASTER, &lsn, NULL, 0); } /* * If there is no master, then we could get into a state * where an old client lost the initial ALIVE message and * is calling an election under an old gen and can * never get to the current gen. */ if (F_ISSET(rep, REP_F_CLIENT) && rp->gen < gen) { MUTEX_LOCK(dbenv, db_rep->rep_mutexp); egen = rep->egen; if (*eidp == rep->master_id) rep->master_id = DB_EID_INVALID; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); data_dbt.data = &egen; data_dbt.size = sizeof(egen); (void)__rep_send_message(dbenv, *eidp, REP_ALIVE, &rp->lsn, &data_dbt, 0); goto errlock; } goto errlock; case REP_NEWFILE: CLIENT_ONLY(rep, rp); MASTER_CHECK(dbenv, *eidp, rep); ret = __rep_apply(dbenv, rp, rec, ret_lsnp, NULL); goto errlock; case REP_NEWMASTER: ANYSITE(rep); if (F_ISSET(rep, REP_F_MASTER) && *eidp != dbenv->rep_eid) { /* We don't hold the rep mutex, and may miscount. */ rep->stat.st_dupmasters++; ret = DB_REP_DUPMASTER; (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_DUPMASTER, NULL, NULL, 0); goto errlock; } ret = __rep_new_master(dbenv, rp, *eidp); goto errlock; case REP_PAGE: case REP_PAGE_MORE: CLIENT_ONLY(rep, rp); MASTER_CHECK(dbenv, *eidp, rep); ret = __rep_page(dbenv, *eidp, rp, rec); break; case REP_PAGE_FAIL: CLIENT_ONLY(rep, rp); MASTER_CHECK(dbenv, *eidp, rep); ret = __rep_page_fail(dbenv, *eidp, rec); break; case REP_PAGE_REQ: MASTER_ONLY(rep, rp); MASTER_UPDATE(dbenv, renv); ret = __rep_page_req(dbenv, *eidp, rec); break; case REP_UPDATE: CLIENT_ONLY(rep, rp); MASTER_CHECK(dbenv, *eidp, rep); ret = __rep_update_setup(dbenv, *eidp, rp, rec); break; case REP_UPDATE_REQ: MASTER_ONLY(rep, rp); infop = dbenv->reginfo; renv = infop->primary; MASTER_UPDATE(dbenv, renv); ret = __rep_update_req(dbenv, *eidp); break; case REP_VERIFY: CLIENT_ONLY(rep, rp); MASTER_CHECK(dbenv, *eidp, rep); if (IS_ZERO_LSN(lp->verify_lsn)) goto errlock; if ((ret = __log_cursor(dbenv, &logc)) != 0) goto errlock; memset(&mylog, 0, sizeof(mylog)); if ((ret = __log_c_get(logc, &rp->lsn, &mylog, DB_SET)) != 0) goto rep_verify_err; match = 0; memcpy(&rectype, mylog.data, sizeof(rectype)); if (mylog.size == rec->size && memcmp(mylog.data, rec->data, rec->size) == 0) match = 1; DB_ASSERT(rectype == DB___txn_ckp); /* * If we don't have a match, backup to the previous * checkpoint and try again. */ if (match == 0) { ZERO_LSN(lsn); if ((ret = __log_backup(dbenv, logc, &rp->lsn, &lsn, LASTCKP_CMP)) == 0) { MUTEX_LOCK(dbenv, db_rep->db_mutexp); lp->verify_lsn = lsn; lp->rcvd_recs = 0; lp->wait_recs = rep->request_gap; MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); (void)__rep_send_message(dbenv, *eidp, REP_VERIFY_REQ, &lsn, NULL, 0); } else if (ret == DB_NOTFOUND) { /* * We've either run out of records because * logs have been removed or we've rolled back * all the way to the beginning. In the latter * we don't think these sites were ever part of * the same environment and we'll say so. * In the former, request internal backup. */ if (rp->lsn.file == 1) { __db_err(dbenv, "Client was never part of master's environment"); ret = EINVAL; } else { rep->stat.st_outdated++; R_LOCK(dbenv, &dblp->reginfo); lsn = lp->lsn; R_UNLOCK(dbenv, &dblp->reginfo); MUTEX_LOCK(dbenv, db_rep->rep_mutexp); F_CLR(rep, REP_F_RECOVER_VERIFY); F_SET(rep, REP_F_RECOVER_UPDATE); ZERO_LSN(rep->first_lsn); MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); (void)__rep_send_message(dbenv, *eidp, REP_UPDATE_REQ, NULL, NULL, 0); } } } else ret = __rep_verify_match(dbenv, &rp->lsn, savetime); rep_verify_err: if ((t_ret = __log_c_close(logc)) != 0 && ret == 0) ret = t_ret; goto errlock; case REP_VERIFY_FAIL: CLIENT_ONLY(rep, rp); MASTER_CHECK(dbenv, *eidp, rep); /* * If any recovery flags are set, but not VERIFY, * then we ignore this message. We are already * in the middle of updating. */ if (F_ISSET(rep, REP_F_RECOVER_MASK) && !F_ISSET(rep, REP_F_RECOVER_VERIFY)) goto errlock; rep->stat.st_outdated++; MUTEX_LOCK(dbenv, db_rep->db_mutexp); MUTEX_LOCK(dbenv, db_rep->rep_mutexp); /* * We don't want an old or delayed VERIFY_FAIL * message to throw us into internal initialization * when we shouldn't be. * * Only go into internal initialization if: * We are in RECOVER_VERIFY and this LSN == verify_lsn. * We are not in any RECOVERY and we are expecting * an LSN that no longer exists on the master. * Otherwise, ignore this message. */ if (((F_ISSET(rep, REP_F_RECOVER_VERIFY)) && log_compare(&rp->lsn, &lp->verify_lsn) == 0) || (F_ISSET(rep, REP_F_RECOVER_MASK) == 0 && log_compare(&rp->lsn, &lp->ready_lsn) >= 0)) { F_CLR(rep, REP_F_RECOVER_VERIFY); F_SET(rep, REP_F_RECOVER_UPDATE); ZERO_LSN(rep->first_lsn); lp->wait_recs = rep->request_gap; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); (void)__rep_send_message(dbenv, *eidp, REP_UPDATE_REQ, NULL, NULL, 0); } else { MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); } goto errlock; case REP_VERIFY_REQ: MASTER_ONLY(rep, rp); type = REP_VERIFY; if ((ret = __log_cursor(dbenv, &logc)) != 0) goto errlock; d = &data_dbt; memset(d, 0, sizeof(data_dbt)); F_SET(logc, DB_LOG_SILENT_ERR); ret = __log_c_get(logc, &rp->lsn, d, DB_SET); /* * If the LSN was invalid, then we might get a not * found, we might get an EIO, we could get anything. * If we get a DB_NOTFOUND, then there is a chance that * the LSN comes before the first file present in which * case we need to return a fail so that the client can return * a DB_OUTDATED. */ if (ret == DB_NOTFOUND && __log_is_outdated(dbenv, rp->lsn.file, &old) == 0 && old != 0) type = REP_VERIFY_FAIL; if (ret != 0) d = NULL; (void)__rep_send_message(dbenv, *eidp, type, &rp->lsn, d, 0); ret = __log_c_close(logc); goto errlock; case REP_VOTE1: if (F_ISSET(rep, REP_F_MASTER)) { RPRINT(dbenv, rep, (dbenv, &mb, "Master received vote")); R_LOCK(dbenv, &dblp->reginfo); lsn = lp->lsn; R_UNLOCK(dbenv, &dblp->reginfo); (void)__rep_send_message(dbenv, *eidp, REP_NEWMASTER, &lsn, NULL, 0); goto errlock; } vi = (REP_VOTE_INFO *)rec->data; MUTEX_LOCK(dbenv, db_rep->rep_mutexp); /* * If we get a vote from a later election gen, we * clear everything from the current one, and we'll * start over by tallying it. If we get an old vote, * send an ALIVE to the old participant. */ RPRINT(dbenv, rep, (dbenv, &mb, "Received vote1 egen %lu, egen %lu", (u_long)vi->egen, (u_long)rep->egen)); if (vi->egen < rep->egen) { RPRINT(dbenv, rep, (dbenv, &mb, "Received old vote %lu, egen %lu, ignoring vote1", (u_long)vi->egen, (u_long)rep->egen)); egen = rep->egen; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); data_dbt.data = &egen; data_dbt.size = sizeof(egen); (void)__rep_send_message(dbenv, *eidp, REP_ALIVE, &rp->lsn, &data_dbt, 0); goto errlock; } if (vi->egen > rep->egen) { RPRINT(dbenv, rep, (dbenv, &mb, "Received VOTE1 from egen %lu, my egen %lu; reset", (u_long)vi->egen, (u_long)rep->egen)); __rep_elect_done(dbenv, rep); rep->egen = vi->egen; } if (!IN_ELECTION(rep)) F_SET(rep, REP_F_TALLY); /* Check if this site knows about more sites than we do. */ if (vi->nsites > rep->nsites) rep->nsites = vi->nsites; /* Check if this site requires more votes than we do. */ if (vi->nvotes > rep->nvotes) rep->nvotes = vi->nvotes; /* * We are keeping the vote, let's see if that changes our * count of the number of sites. */ if (rep->sites + 1 > rep->nsites) rep->nsites = rep->sites + 1; if (rep->nsites > rep->asites && (ret = __rep_grow_sites(dbenv, rep->nsites)) != 0) { RPRINT(dbenv, rep, (dbenv, &mb, "Grow sites returned error %d", ret)); goto errunlock; } /* * Ignore vote1's if we're in phase 2. */ if (F_ISSET(rep, REP_F_EPHASE2)) { RPRINT(dbenv, rep, (dbenv, &mb, "In phase 2, ignoring vote1")); goto errunlock; } /* * Record this vote. If we get back non-zero, we * ignore the vote. */ if ((ret = __rep_tally(dbenv, rep, *eidp, &rep->sites, vi->egen, rep->tally_off)) != 0) { RPRINT(dbenv, rep, (dbenv, &mb, "Tally returned %d, sites %d", ret, rep->sites)); ret = 0; goto errunlock; } RPRINT(dbenv, rep, (dbenv, &mb, "Incoming vote: (eid)%d (pri)%d (gen)%lu (egen)%lu [%lu,%lu]", *eidp, vi->priority, (u_long)rp->gen, (u_long)vi->egen, (u_long)rp->lsn.file, (u_long)rp->lsn.offset)); #ifdef DIAGNOSTIC if (rep->sites > 1) RPRINT(dbenv, rep, (dbenv, &mb, "Existing vote: (eid)%d (pri)%d (gen)%lu (sites)%d [%lu,%lu]", rep->winner, rep->w_priority, (u_long)rep->w_gen, rep->sites, (u_long)rep->w_lsn.file, (u_long)rep->w_lsn.offset)); #endif __rep_cmp_vote(dbenv, rep, eidp, &rp->lsn, vi->priority, rp->gen, vi->tiebreaker); /* * If you get a vote and you're not in an election, we've * already recorded this vote. But that is all we need * to do. */ if (!IN_ELECTION(rep)) { RPRINT(dbenv, rep, (dbenv, &mb, "Not in election, but received vote1 0x%x", rep->flags)); ret = DB_REP_HOLDELECTION; goto errunlock; } master = rep->winner; lsn = rep->w_lsn; /* * We need to check sites == nsites, not more than half * like we do in __rep_elect and the VOTE2 code below. The * reason is that we want to process all the incoming votes * and not short-circuit once we reach more than half. The * real winner's vote may be in the last half. */ done = rep->sites >= rep->nsites && rep->w_priority != 0; if (done) { RPRINT(dbenv, rep, (dbenv, &mb, "Phase1 election done")); RPRINT(dbenv, rep, (dbenv, &mb, "Voting for %d%s", master, master == rep->eid ? "(self)" : "")); egen = rep->egen; F_SET(rep, REP_F_EPHASE2); F_CLR(rep, REP_F_EPHASE1); if (master == rep->eid) { (void)__rep_tally(dbenv, rep, rep->eid, &rep->votes, egen, rep->v2tally_off); goto errunlock; } MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); /* Vote for someone else. */ __rep_send_vote(dbenv, NULL, 0, 0, 0, 0, egen, master, REP_VOTE2); } else MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); /* Election is still going on. */ break; case REP_VOTE2: RPRINT(dbenv, rep, (dbenv, &mb, "We received a vote%s", F_ISSET(rep, REP_F_MASTER) ? " (master)" : "")); if (F_ISSET(rep, REP_F_MASTER)) { R_LOCK(dbenv, &dblp->reginfo); lsn = lp->lsn; R_UNLOCK(dbenv, &dblp->reginfo); rep->stat.st_elections_won++; (void)__rep_send_message(dbenv, *eidp, REP_NEWMASTER, &lsn, NULL, 0); goto errlock; } MUTEX_LOCK(dbenv, db_rep->rep_mutexp); /* If we have priority 0, we should never get a vote. */ DB_ASSERT(rep->priority != 0); /* * We might be the last to the party and we haven't had * time to tally all the vote1's, but others have and * decided we're the winner. So, if we're in the process * of tallying sites, keep the vote so that when our * election thread catches up we'll have the votes we * already received. */ vi = (REP_VOTE_INFO *)rec->data; if (!IN_ELECTION_TALLY(rep) && vi->egen >= rep->egen) { RPRINT(dbenv, rep, (dbenv, &mb, "Not in election gen %lu, at %lu, got vote", (u_long)vi->egen, (u_long)rep->egen)); ret = DB_REP_HOLDELECTION; goto errunlock; } /* * Record this vote. In a VOTE2, the only valid entry * in the REP_VOTE_INFO is the election generation. * * There are several things which can go wrong that we * need to account for: * 1. If we receive a latent VOTE2 from an earlier election, * we want to ignore it. * 2. If we receive a VOTE2 from a site from which we never * received a VOTE1, we want to ignore it. * 3. If we have received a duplicate VOTE2 from this election * from the same site we want to ignore it. * 4. If this is from the current election and someone is * really voting for us, then we finally get to record it. */ /* * __rep_cmp_vote2 checks for cases 1 and 2. */ if ((ret = __rep_cmp_vote2(dbenv, rep, *eidp, vi->egen)) != 0) { ret = 0; goto errunlock; } /* * __rep_tally takes care of cases 3 and 4. */ if ((ret = __rep_tally(dbenv, rep, *eidp, &rep->votes, vi->egen, rep->v2tally_off)) != 0) { ret = 0; goto errunlock; } done = rep->votes >= rep->nvotes; RPRINT(dbenv, rep, (dbenv, &mb, "Counted vote %d of %d", rep->votes, rep->nvotes)); if (done) { __rep_elect_master(dbenv, rep, eidp); ret = DB_REP_NEWMASTER; goto errunlock; } else MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); break; default: __db_err(dbenv, "DB_ENV->rep_process_message: unknown replication message: type %lu", (u_long)rp->rectype); ret = EINVAL; goto errlock; } /* * If we already hold rep_mutexp then we goto 'errunlock' * Otherwise we goto 'errlock' to acquire it before we * decrement our message thread count. */ errlock: MUTEX_LOCK(dbenv, db_rep->rep_mutexp); errunlock: rep->msg_th--; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); out: if (ret == 0 && F_ISSET(rp, DB_LOG_PERM)) { if (ret_lsnp != NULL) *ret_lsnp = rp->lsn; ret = DB_REP_NOTPERM; } return (ret); } /* * __rep_apply -- * * Handle incoming log records on a client, applying when possible and * entering into the bookkeeping table otherwise. This routine manages * the state of the incoming message stream -- processing records, via * __rep_process_rec, when possible and enqueuing in the __db.rep.db * when necessary. As gaps in the stream are filled in, this is where * we try to process as much as possible from __db.rep.db to catch up. */ static int __rep_apply(dbenv, rp, rec, ret_lsnp, is_dupp) DB_ENV *dbenv; REP_CONTROL *rp; DBT *rec; DB_LSN *ret_lsnp; int *is_dupp; { DB_REP *db_rep; DBT control_dbt, key_dbt; DBT rec_dbt; DB *dbp; DB_LOG *dblp; DB_LSN max_lsn; LOG *lp; REP *rep; u_int32_t rectype; int cmp, ret; #ifdef DIAGNOSTIC DB_MSGBUF mb; #endif db_rep = dbenv->rep_handle; rep = db_rep->region; dbp = db_rep->rep_db; rectype = 0; ret = 0; memset(&control_dbt, 0, sizeof(control_dbt)); memset(&rec_dbt, 0, sizeof(rec_dbt)); ZERO_LSN(max_lsn); dblp = dbenv->lg_handle; MUTEX_LOCK(dbenv, db_rep->db_mutexp); lp = dblp->reginfo.primary; MUTEX_LOCK(dbenv, db_rep->rep_mutexp); if (F_ISSET(rep, REP_F_RECOVER_LOG) && log_compare(&lp->ready_lsn, &rep->first_lsn) < 0) lp->ready_lsn = rep->first_lsn; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); cmp = log_compare(&rp->lsn, &lp->ready_lsn); if (cmp == 0) { if ((ret = __rep_process_rec(dbenv, rp, rec, &rectype, &max_lsn)) != 0) goto err; /* * If we get the record we are expecting, reset * the count of records we've received and are applying * towards the request interval. */ lp->rcvd_recs = 0; while (ret == 0 && log_compare(&lp->ready_lsn, &lp->waiting_lsn) == 0) { /* * We just filled in a gap in the log record stream. * Write subsequent records to the log. */ gap_check: lp->rcvd_recs = 0; ZERO_LSN(lp->max_wait_lsn); if ((ret = __rep_remfirst(dbenv, &control_dbt, &rec_dbt)) != 0) goto err; rp = (REP_CONTROL *)control_dbt.data; rec = &rec_dbt; if ((ret = __rep_process_rec(dbenv, rp, rec, &rectype, &max_lsn)) != 0) goto err; /* * We may miscount, as we don't hold the rep mutex. */ --rep->stat.st_log_queued; if ((ret = __rep_getnext(dbenv)) == DB_NOTFOUND) { ret = 0; break; } else if (ret != 0) goto err; } /* * Check if we're at a gap in the table and if so, whether we * need to ask for any records. */ if (!IS_ZERO_LSN(lp->waiting_lsn) && log_compare(&lp->ready_lsn, &lp->waiting_lsn) != 0) { /* * We got a record and processed it, but we may * still be waiting for more records. */ if (__rep_check_doreq(dbenv, rep)) __rep_loggap_req(dbenv, rep, &rp->lsn, 0); } else { lp->wait_recs = 0; ZERO_LSN(lp->max_wait_lsn); } } else if (cmp > 0) { /* * The LSN is higher than the one we were waiting for. * This record isn't in sequence; add it to the temporary * database, update waiting_lsn if necessary, and perform * calculations to determine if we should issue requests * for new records. */ memset(&key_dbt, 0, sizeof(key_dbt)); key_dbt.data = rp; key_dbt.size = sizeof(*rp); if (lp->wait_recs == 0) { /* * This is a new gap. Initialize the number of * records that we should wait before requesting * that it be resent. We grab the limits out of * the rep without the mutex. */ lp->wait_recs = rep->request_gap; lp->rcvd_recs = 0; ZERO_LSN(lp->max_wait_lsn); } if (__rep_check_doreq(dbenv, rep)) __rep_loggap_req(dbenv, rep, &rp->lsn, 0); ret = __db_put(dbp, NULL, &key_dbt, rec, DB_NOOVERWRITE); rep->stat.st_log_queued++; rep->stat.st_log_queued_total++; if (rep->stat.st_log_queued_max < rep->stat.st_log_queued) rep->stat.st_log_queued_max = rep->stat.st_log_queued; if (ret == DB_KEYEXIST) ret = 0; if (ret != 0) goto done; if (IS_ZERO_LSN(lp->waiting_lsn) || log_compare(&rp->lsn, &lp->waiting_lsn) < 0) lp->waiting_lsn = rp->lsn; /* * If this is permanent; let the caller know that we have * not yet written it to disk, but we've accepted it. */ if (ret == 0 && F_ISSET(rp, DB_LOG_PERM)) { max_lsn = rp->lsn; ret = DB_REP_NOTPERM; } goto done; } else { /* * We may miscount if we race, since we * don't currently hold the rep mutex. */ rep->stat.st_log_duplicated++; if (is_dupp != NULL) *is_dupp = 1; if (F_ISSET(rp, DB_LOG_PERM)) max_lsn = lp->max_perm_lsn; goto done; } /* Check if we need to go back into the table. */ if (ret == 0 && log_compare(&lp->ready_lsn, &lp->waiting_lsn) == 0) goto gap_check; done: err: /* Check if we need to go back into the table. */ MUTEX_LOCK(dbenv, db_rep->rep_mutexp); if (ret == 0 && F_ISSET(rep, REP_F_RECOVER_LOG) && log_compare(&lp->ready_lsn, &rep->last_lsn) >= 0) { rep->last_lsn = max_lsn; ZERO_LSN(max_lsn); ret = DB_REP_LOGREADY; } MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); if (ret == 0 && !F_ISSET(rep, REP_F_RECOVER_LOG) && !IS_ZERO_LSN(max_lsn)) { if (ret_lsnp != NULL) *ret_lsnp = max_lsn; ret = DB_REP_ISPERM; DB_ASSERT(log_compare(&max_lsn, &lp->max_perm_lsn) >= 0); lp->max_perm_lsn = max_lsn; } MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); /* * Startup is complete when we process our first live record. However, * we want to return DB_REP_STARTUPDONE on the first record we can -- * but other return values trump this one. We know we've processed at * least one record when rectype is non-zero. */ if (ret == 0 && !F_ISSET(rp, DB_LOG_RESEND) && rectype != 0 && rep->stat.st_startup_complete == 0) { rep->stat.st_startup_complete = 1; ret = DB_REP_STARTUPDONE; } if (ret == 0 && rp->rectype == REP_NEWFILE && lp->db_log_autoremove) __log_autoremove(dbenv); if (control_dbt.data != NULL) __os_ufree(dbenv, control_dbt.data); if (rec_dbt.data != NULL) __os_ufree(dbenv, rec_dbt.data); if (ret == DB_REP_NOTPERM && !F_ISSET(rep, REP_F_RECOVER_LOG) && !IS_ZERO_LSN(max_lsn) && ret_lsnp != NULL) *ret_lsnp = max_lsn; #ifdef DIAGNOSTIC if (ret == DB_REP_ISPERM) RPRINT(dbenv, rep, (dbenv, &mb, "Returning ISPERM [%lu][%lu]", (u_long)max_lsn.file, (u_long)max_lsn.offset)); else if (ret == DB_REP_LOGREADY) RPRINT(dbenv, rep, (dbenv, &mb, "Returning LOGREADY up to [%lu][%lu]", (u_long)rep->last_lsn.file, (u_long)rep->last_lsn.offset)); else if (ret == DB_REP_NOTPERM) RPRINT(dbenv, rep, (dbenv, &mb, "Returning NOTPERM [%lu][%lu]", (u_long)max_lsn.file, (u_long)max_lsn.offset)); else if (ret == DB_REP_STARTUPDONE) RPRINT(dbenv, rep, (dbenv, &mb, "Returning STARTUPDONE [%lu][%lu]", (u_long)rp->lsn.file, (u_long)rp->lsn.offset)); else if (ret != 0) RPRINT(dbenv, rep, (dbenv, &mb, "Returning %d [%lu][%lu]", ret, (u_long)max_lsn.file, (u_long)max_lsn.offset)); #endif return (ret); } /* * __rep_process_txn -- * * This is the routine that actually gets a transaction ready for * processing. * * PUBLIC: int __rep_process_txn __P((DB_ENV *, DBT *)); */ int __rep_process_txn(dbenv, rec) DB_ENV *dbenv; DBT *rec; { DBT data_dbt, *lock_dbt; DB_LOCKREQ req, *lvp; DB_LOGC *logc; DB_LSN prev_lsn, *lsnp; DB_REP *db_rep; LSN_COLLECTION lc; REP *rep; __txn_regop_args *txn_args; __txn_xa_regop_args *prep_args; u_int32_t lockid, rectype; u_int i; int ret, t_ret; void *txninfo; db_rep = dbenv->rep_handle; rep = db_rep->region; logc = NULL; txn_args = NULL; prep_args = NULL; txninfo = NULL; memset(&data_dbt, 0, sizeof(data_dbt)); if (F_ISSET(dbenv, DB_ENV_THREAD)) F_SET(&data_dbt, DB_DBT_REALLOC); /* * There are two phases: First, we have to traverse backwards through * the log records gathering the list of all LSNs in the transaction. * Once we have this information, we can loop through and then apply it. * * We may be passed a prepare (if we're restoring a prepare on upgrade) * instead of a commit (the common case). Check which it is and behave * appropriately. */ memcpy(&rectype, rec->data, sizeof(rectype)); memset(&lc, 0, sizeof(lc)); if (rectype == DB___txn_regop) { /* * We're the end of a transaction. Make sure this is * really a commit and not an abort! */ if ((ret = __txn_regop_read(dbenv, rec->data, &txn_args)) != 0) return (ret); if (txn_args->opcode != TXN_COMMIT) { __os_free(dbenv, txn_args); return (0); } prev_lsn = txn_args->prev_lsn; lock_dbt = &txn_args->locks; } else { /* We're a prepare. */ DB_ASSERT(rectype == DB___txn_xa_regop); if ((ret = __txn_xa_regop_read(dbenv, rec->data, &prep_args)) != 0) return (ret); prev_lsn = prep_args->prev_lsn; lock_dbt = &prep_args->locks; } /* Get locks. */ if ((ret = __lock_id(dbenv, &lockid)) != 0) goto err1; if ((ret = __lock_get_list(dbenv, lockid, 0, DB_LOCK_WRITE, lock_dbt)) != 0) goto err; /* Phase 1. Get a list of the LSNs in this transaction, and sort it. */ if ((ret = __rep_collect_txn(dbenv, &prev_lsn, &lc)) != 0) goto err; qsort(lc.array, lc.nlsns, sizeof(DB_LSN), __rep_lsn_cmp); /* * The set of records for a transaction may include dbreg_register * records. Create a txnlist so that they can keep track of file * state between records. */ if ((ret = __db_txnlist_init(dbenv, 0, 0, NULL, &txninfo)) != 0) goto err; /* Phase 2: Apply updates. */ if ((ret = __log_cursor(dbenv, &logc)) != 0) goto err; for (lsnp = &lc.array[0], i = 0; i < lc.nlsns; i++, lsnp++) { if ((ret = __log_c_get(logc, lsnp, &data_dbt, DB_SET)) != 0) { __db_err(dbenv, "failed to read the log at [%lu][%lu]", (u_long)lsnp->file, (u_long)lsnp->offset); goto err; } if ((ret = __db_dispatch(dbenv, dbenv->recover_dtab, dbenv->recover_dtab_size, &data_dbt, lsnp, DB_TXN_APPLY, txninfo)) != 0) { __db_err(dbenv, "transaction failed at [%lu][%lu]", (u_long)lsnp->file, (u_long)lsnp->offset); goto err; } } err: memset(&req, 0, sizeof(req)); req.op = DB_LOCK_PUT_ALL; if ((t_ret = __lock_vec(dbenv, lockid, 0, &req, 1, &lvp)) != 0 && ret == 0) ret = t_ret; if ((t_ret = __lock_id_free(dbenv, lockid)) != 0 && ret == 0) ret = t_ret; err1: if (txn_args != NULL) __os_free(dbenv, txn_args); if (prep_args != NULL) __os_free(dbenv, prep_args); if (lc.array != NULL) __os_free(dbenv, lc.array); if (logc != NULL && (t_ret = __log_c_close(logc)) != 0 && ret == 0) ret = t_ret; if (txninfo != NULL) __db_txnlist_end(dbenv, txninfo); if (F_ISSET(&data_dbt, DB_DBT_REALLOC) && data_dbt.data != NULL) __os_ufree(dbenv, data_dbt.data); if (ret == 0) /* * We don't hold the rep mutex, and could miscount if we race. */ rep->stat.st_txns_applied++; return (ret); } /* * __rep_collect_txn * Recursive function that will let us visit every entry in a transaction * chain including all child transactions so that we can then apply * the entire transaction family at once. */ static int __rep_collect_txn(dbenv, lsnp, lc) DB_ENV *dbenv; DB_LSN *lsnp; LSN_COLLECTION *lc; { __txn_child_args *argp; DB_LOGC *logc; DB_LSN c_lsn; DBT data; u_int32_t rectype; u_int nalloc; int ret, t_ret; memset(&data, 0, sizeof(data)); F_SET(&data, DB_DBT_REALLOC); if ((ret = __log_cursor(dbenv, &logc)) != 0) return (ret); while (!IS_ZERO_LSN(*lsnp) && (ret = __log_c_get(logc, lsnp, &data, DB_SET)) == 0) { memcpy(&rectype, data.data, sizeof(rectype)); if (rectype == DB___txn_child) { if ((ret = __txn_child_read(dbenv, data.data, &argp)) != 0) goto err; c_lsn = argp->c_lsn; *lsnp = argp->prev_lsn; __os_free(dbenv, argp); ret = __rep_collect_txn(dbenv, &c_lsn, lc); } else { if (lc->nalloc < lc->nlsns + 1) { nalloc = lc->nalloc == 0 ? 20 : lc->nalloc * 2; if ((ret = __os_realloc(dbenv, nalloc * sizeof(DB_LSN), &lc->array)) != 0) goto err; lc->nalloc = nalloc; } lc->array[lc->nlsns++] = *lsnp; /* * Explicitly copy the previous lsn. The record * starts with a u_int32_t record type, a u_int32_t * txn id, and then the DB_LSN (prev_lsn) that we * want. We copy explicitly because we have no idea * what kind of record this is. */ memcpy(lsnp, (u_int8_t *)data.data + sizeof(u_int32_t) + sizeof(u_int32_t), sizeof(DB_LSN)); } if (ret != 0) goto err; } if (ret != 0) __db_err(dbenv, "collect failed at: [%lu][%lu]", (u_long)lsnp->file, (u_long)lsnp->offset); err: if ((t_ret = __log_c_close(logc)) != 0 && ret == 0) ret = t_ret; if (data.data != NULL) __os_ufree(dbenv, data.data); return (ret); } /* * __rep_lsn_cmp -- * qsort-type-compatible wrapper for log_compare. */ static int __rep_lsn_cmp(lsn1, lsn2) const void *lsn1, *lsn2; { return (log_compare((DB_LSN *)lsn1, (DB_LSN *)lsn2)); } /* * __rep_newfile -- * NEWFILE messages have the LSN of the last record in the previous * log file. When applying a NEWFILE message, make sure we haven't already * swapped files. */ static int __rep_newfile(dbenv, rc, lsnp) DB_ENV *dbenv; REP_CONTROL *rc; DB_LSN *lsnp; { DB_LOG *dblp; LOG *lp; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; if (rc->lsn.file + 1 > lp->lsn.file) return (__log_newfile(dblp, lsnp, 0)); else { /* We've already applied this NEWFILE. Just ignore it. */ *lsnp = lp->lsn; return (0); } } /* * __rep_tally -- * PUBLIC: int __rep_tally __P((DB_ENV *, REP *, int, int *, * PUBLIC: u_int32_t, roff_t)); * * Handle incoming vote1 message on a client. Called with the db_rep * mutex held. This function will return 0 if we successfully tally * the vote and non-zero if the vote is ignored. This will record * both VOTE1 and VOTE2 records, depending on which region offset the * caller passed in. */ int __rep_tally(dbenv, rep, eid, countp, egen, vtoff) DB_ENV *dbenv; REP *rep; int eid, *countp; u_int32_t egen; roff_t vtoff; { REP_VTALLY *tally, *vtp; int i; #ifdef DIAGNOSTIC DB_MSGBUF mb; #else COMPQUIET(rep, NULL); #endif tally = R_ADDR((REGINFO *)dbenv->reginfo, vtoff); i = 0; vtp = &tally[i]; while (i < *countp) { /* * Ignore votes from earlier elections (i.e. we've heard * from this site in this election, but its vote from an * earlier election got delayed and we received it now). * However, if we happened to hear from an earlier vote * and we recorded it and we're now hearing from a later * election we want to keep the updated one. Note that * updating the entry will not increase the count. * Also ignore votes that are duplicates. */ if (vtp->eid == eid) { RPRINT(dbenv, rep, (dbenv, &mb, "Tally found[%d] (%d, %lu), this vote (%d, %lu)", i, vtp->eid, (u_long)vtp->egen, eid, (u_long)egen)); if (vtp->egen >= egen) return (1); else { vtp->egen = egen; return (0); } } i++; vtp = &tally[i]; } /* * If we get here, we have a new voter we haven't * seen before. Tally this vote. */ #ifdef DIAGNOSTIC if (vtoff == rep->tally_off) RPRINT(dbenv, rep, (dbenv, &mb, "Tallying VOTE1[%d] (%d, %lu)", i, eid, (u_long)egen)); else RPRINT(dbenv, rep, (dbenv, &mb, "Tallying VOTE2[%d] (%d, %lu)", i, eid, (u_long)egen)); #endif vtp->eid = eid; vtp->egen = egen; (*countp)++; return (0); } /* * __rep_cmp_vote -- * PUBLIC: void __rep_cmp_vote __P((DB_ENV *, REP *, int *, DB_LSN *, * PUBLIC: int, u_int32_t, u_int32_t)); * * Compare incoming vote1 message on a client. Called with the db_rep * mutex held. */ void __rep_cmp_vote(dbenv, rep, eidp, lsnp, priority, gen, tiebreaker) DB_ENV *dbenv; REP *rep; int *eidp; DB_LSN *lsnp; int priority; u_int32_t gen, tiebreaker; { int cmp; #ifdef DIAGNOSTIC DB_MSGBUF mb; #else COMPQUIET(dbenv, NULL); #endif cmp = log_compare(lsnp, &rep->w_lsn); /* * If we've seen more than one, compare us to the best so far. * If we're the first, make ourselves the winner to start. */ if (rep->sites > 1 && priority != 0) { /* * LSN is primary determinant. Then priority if LSNs * are equal, then tiebreaker if both are equal. */ if (cmp > 0 || (cmp == 0 && (priority > rep->w_priority || (priority == rep->w_priority && (tiebreaker > rep->w_tiebreaker))))) { RPRINT(dbenv, rep, (dbenv, &mb, "Accepting new vote")); rep->winner = *eidp; rep->w_priority = priority; rep->w_lsn = *lsnp; rep->w_gen = gen; rep->w_tiebreaker = tiebreaker; } } else if (rep->sites == 1) { if (priority != 0) { /* Make ourselves the winner to start. */ rep->winner = *eidp; rep->w_priority = priority; rep->w_gen = gen; rep->w_lsn = *lsnp; rep->w_tiebreaker = tiebreaker; } else { rep->winner = DB_EID_INVALID; rep->w_priority = 0; rep->w_gen = 0; ZERO_LSN(rep->w_lsn); rep->w_tiebreaker = 0; } } return; } /* * __rep_cmp_vote2 -- * PUBLIC: int __rep_cmp_vote2 __P((DB_ENV *, REP *, int, u_int32_t)); * * Compare incoming vote2 message with vote1's we've recorded. Called * with the db_rep mutex held. We return 0 if the VOTE2 is from a * site we've heard from and it is from this election. Otherwise we return 1. */ int __rep_cmp_vote2(dbenv, rep, eid, egen) DB_ENV *dbenv; REP *rep; int eid; u_int32_t egen; { int i; REP_VTALLY *tally, *vtp; #ifdef DIAGNOSTIC DB_MSGBUF mb; #endif tally = R_ADDR((REGINFO *)dbenv->reginfo, rep->tally_off); i = 0; vtp = &tally[i]; for (i = 0; i < rep->sites; i++) { vtp = &tally[i]; if (vtp->eid == eid && vtp->egen == egen) { RPRINT(dbenv, rep, (dbenv, &mb, "Found matching vote1 (%d, %lu), at %d of %d", eid, (u_long)egen, i, rep->sites)); return (0); } } RPRINT(dbenv, rep, (dbenv, &mb, "Didn't find vote1 for eid %d, egen %lu", eid, (u_long)egen)); return (1); } static int __rep_dorecovery(dbenv, lsnp, trunclsnp) DB_ENV *dbenv; DB_LSN *lsnp, *trunclsnp; { DB_LSN lsn; DB_REP *db_rep; DBT mylog; DB_LOGC *logc; int ret, t_ret, update; u_int32_t rectype; __txn_regop_args *txnrec; db_rep = dbenv->rep_handle; /* Figure out if we are backing out any committed transactions. */ if ((ret = __log_cursor(dbenv, &logc)) != 0) return (ret); memset(&mylog, 0, sizeof(mylog)); update = 0; while (update == 0 && (ret = __log_c_get(logc, &lsn, &mylog, DB_PREV)) == 0 && log_compare(&lsn, lsnp) > 0) { memcpy(&rectype, mylog.data, sizeof(rectype)); if (rectype == DB___txn_regop) { if ((ret = __txn_regop_read(dbenv, mylog.data, &txnrec)) != 0) goto err; if (txnrec->opcode != TXN_ABORT) update = 1; __os_free(dbenv, txnrec); } } /* * If we successfully run recovery, we've opened all the necessary * files. We are guaranteed to be single-threaded here, so no mutex * is necessary. */ if ((ret = __db_apprec(dbenv, lsnp, trunclsnp, update, 0)) == 0) F_SET(db_rep, DBREP_OPENFILES); err: if ((t_ret = __log_c_close(logc)) != 0 && ret == 0) ret = t_ret; return (ret); } /* * __rep_verify_match -- * We have just received a matching log record during verification. * Figure out if we're going to need to run recovery. If so, wait until * everything else has exited the library. If not, set up the world * correctly and move forward. */ static int __rep_verify_match(dbenv, reclsnp, savetime) DB_ENV *dbenv; DB_LSN *reclsnp; time_t savetime; { DB_LOG *dblp; DB_LSN trunclsn; DB_REP *db_rep; LOG *lp; REGENV *renv; REGINFO *infop; REP *rep; int done, master, ret; u_int32_t unused; dblp = dbenv->lg_handle; db_rep = dbenv->rep_handle; rep = db_rep->region; lp = dblp->reginfo.primary; ret = 0; infop = dbenv->reginfo; renv = infop->primary; /* * Check if the savetime is different than our current time stamp. * If it is, then we're racing with another thread trying to recover * and we lost. We must give up. */ MUTEX_LOCK(dbenv, db_rep->db_mutexp); done = savetime != renv->rep_timestamp; if (done) { MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); return (0); } ZERO_LSN(lp->verify_lsn); MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); /* * Make sure the world hasn't changed while we tried to get * the lock. If it hasn't then it's time for us to kick all * operations out of DB and run recovery. */ MUTEX_LOCK(dbenv, db_rep->rep_mutexp); if (!F_ISSET(rep, REP_F_RECOVER_LOG) && (F_ISSET(rep, REP_F_READY) || rep->in_recovery != 0)) { rep->stat.st_msgs_recover++; goto errunlock; } __rep_lockout(dbenv, db_rep, rep, 1); /* OK, everyone is out, we can now run recovery. */ MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); if ((ret = __rep_dorecovery(dbenv, reclsnp, &trunclsn)) != 0) { MUTEX_LOCK(dbenv, db_rep->rep_mutexp); rep->in_recovery = 0; F_CLR(rep, REP_F_READY); goto errunlock; } /* * The log has been truncated (either directly by us or by __db_apprec) * We want to make sure we're waiting for the LSN at the new end-of-log, * not some later point. */ MUTEX_LOCK(dbenv, db_rep->db_mutexp); lp->ready_lsn = trunclsn; ZERO_LSN(lp->waiting_lsn); ZERO_LSN(lp->max_wait_lsn); lp->max_perm_lsn = *reclsnp; lp->wait_recs = 0; lp->rcvd_recs = 0; ZERO_LSN(lp->verify_lsn); /* * Discard any log records we have queued; we're about to re-request * them, and can't trust the ones in the queue. We need to set the * DB_AM_RECOVER bit in this handle, so that the operation doesn't * deadlock. */ F_SET(db_rep->rep_db, DB_AM_RECOVER); MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); ret = __db_truncate(db_rep->rep_db, NULL, &unused); MUTEX_LOCK(dbenv, db_rep->db_mutexp); F_CLR(db_rep->rep_db, DB_AM_RECOVER); MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); MUTEX_LOCK(dbenv, db_rep->rep_mutexp); rep->stat.st_log_queued = 0; rep->in_recovery = 0; F_CLR(rep, REP_F_NOARCHIVE | REP_F_RECOVER_MASK); if (ret != 0) goto errunlock; /* * If the master_id is invalid, this means that since * the last record was sent, somebody declared an * election and we may not have a master to request * things of. * * This is not an error; when we find a new master, * we'll re-negotiate where the end of the log is and * try to bring ourselves up to date again anyway. * * !!! * We cannot assert the election flags though because * somebody may have declared an election and then * got an error, thus clearing the election flags * but we still have an invalid master_id. */ master = rep->master_id; MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); if (master == DB_EID_INVALID) ret = 0; else (void)__rep_send_message(dbenv, master, REP_ALL_REQ, reclsnp, NULL, 0); if (0) { errunlock: MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); } return (ret); } /* * __rep_do_ckp -- * Perform the memp_sync necessary for this checkpoint without holding * the db_rep->db_mutexp. All callers of this function must hold the * db_rep->db_mutexp and must not be holding the db_rep->rep_mutexp. */ static int __rep_do_ckp(dbenv, rec, rp) DB_ENV *dbenv; DBT *rec; REP_CONTROL *rp; { DB_LSN ckp_lsn; DB_REP *db_rep; int ret; db_rep = dbenv->rep_handle; MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); DB_TEST_CHECKPOINT(dbenv, dbenv->test_check); /* Sync the memory pool. */ memcpy(&ckp_lsn, (u_int8_t *)rec->data + SSZ(__txn_ckp_args, ckp_lsn), sizeof(DB_LSN)); ret = __memp_sync(dbenv, &ckp_lsn); /* Update the last_ckp in the txn region. */ if (ret == 0) __txn_updateckp(dbenv, &rp->lsn); else { __db_err(dbenv, "Error syncing ckp [%lu][%lu]", (u_long)ckp_lsn.file, (u_long)ckp_lsn.offset); ret = __db_panic(dbenv, ret); } MUTEX_LOCK(dbenv, db_rep->db_mutexp); return (ret); } /* * __rep_remfirst -- * Remove the first entry from the __db.rep.db */ static int __rep_remfirst(dbenv, cntrl, rec) DB_ENV *dbenv; DBT *cntrl; DBT *rec; { DB *dbp; DBC *dbc; DB_REP *db_rep; int ret, t_ret; u_int32_t rectype; db_rep = dbenv->rep_handle; dbp = db_rep->rep_db; if ((ret = __db_cursor(dbp, NULL, &dbc, 0)) != 0) return (ret); /* The DBTs need to persist through another call. */ F_SET(cntrl, DB_DBT_REALLOC); F_SET(rec, DB_DBT_REALLOC); if ((ret = __db_c_get(dbc, cntrl, rec, DB_RMW | DB_FIRST)) == 0) { memcpy(&rectype, rec->data, sizeof(rectype)); ret = __db_c_del(dbc, 0); } if ((t_ret = __db_c_close(dbc)) != 0 && ret == 0) ret = t_ret; return (ret); } /* * __rep_getnext -- * Get the next record out of the __db.rep.db table. */ static int __rep_getnext(dbenv) DB_ENV *dbenv; { DB *dbp; DB_REP *db_rep; DB_LOG *dblp; DBC *dbc; DBT lsn_dbt, nextrec_dbt; LOG *lp; REP_CONTROL *rp; int ret, t_ret; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; db_rep = dbenv->rep_handle; dbp = db_rep->rep_db; if ((ret = __db_cursor(dbp, NULL, &dbc, 0)) != 0) return (ret); /* * Update waiting_lsn. We need to move it * forward to the LSN of the next record * in the queue. * * If the next item in the database is a log * record--the common case--we're not * interested in its contents, just in its LSN. * Optimize by doing a partial get of the data item. */ memset(&nextrec_dbt, 0, sizeof(nextrec_dbt)); F_SET(&nextrec_dbt, DB_DBT_PARTIAL); nextrec_dbt.ulen = nextrec_dbt.dlen = 0; memset(&lsn_dbt, 0, sizeof(lsn_dbt)); ret = __db_c_get(dbc, &lsn_dbt, &nextrec_dbt, DB_FIRST); if (ret != DB_NOTFOUND && ret != 0) goto err; if (ret == DB_NOTFOUND) { ZERO_LSN(lp->waiting_lsn); /* * Whether or not the current record is * simple, there's no next one, and * therefore we haven't got anything * else to do right now. Break out. */ goto err; } rp = (REP_CONTROL *)lsn_dbt.data; lp->waiting_lsn = rp->lsn; err: if ((t_ret = __db_c_close(dbc)) != 0 && ret == 0) ret = t_ret; return (ret); } /* * __rep_process_rec -- * * Given a record in 'rp', process it. In the case of a NEWFILE, that means * potentially switching files. In the case of a checkpoint, it means doing * the checkpoint, and in other cases, it means simply writing the record into * the log. */ static int __rep_process_rec(dbenv, rp, rec, typep, ret_lsnp) DB_ENV *dbenv; REP_CONTROL *rp; DBT *rec; u_int32_t *typep; DB_LSN *ret_lsnp; { DB *dbp; DB_LOG *dblp; DB_REP *db_rep; DBT control_dbt, key_dbt, rec_dbt; LOG *lp; REP *rep; u_int32_t txnid; int ret, t_ret; db_rep = dbenv->rep_handle; rep = db_rep->region; dbp = db_rep->rep_db; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; ret = 0; if (rp->rectype == REP_NEWFILE) { ret = __rep_newfile(dbenv, rp, &lp->ready_lsn); /* Make this evaluate to a simple rectype. */ *typep = 0; return (0); } memcpy(typep, rec->data, sizeof(*typep)); memset(&control_dbt, 0, sizeof(control_dbt)); memset(&rec_dbt, 0, sizeof(rec_dbt)); /* * We write all records except for checkpoint records here. * All non-checkpoint records need to appear in the log before * we take action upon them (i.e., we enforce write-ahead logging). * However, we can't write the checkpoint record here until the * data buffers are actually written to disk, else we are creating * an invalid log -- one that says all data before a certain point * has been written to disk. * * If two threads are both processing the same checkpoint record * (because, for example, it was resent and the original finally * arrived), we handle that below by checking for the existence of * the log record when we add it to the replication database. * * Any log records that arrive while we are processing the checkpoint * are added to the bookkeeping database because ready_lsn is not yet * updated to point after the checkpoint record. */ if (*typep != DB___txn_ckp || F_ISSET(rep, REP_F_RECOVER_LOG)) { if ((ret = __log_rep_put(dbenv, &rp->lsn, rec)) != 0) return (ret); rep->stat.st_log_records++; if (F_ISSET(rep, REP_F_RECOVER_LOG)) { *ret_lsnp = rp->lsn; goto out; } } switch (*typep) { case DB___dbreg_register: /* * DB opens occur in the context of a transaction, so we can * simply handle them when we process the transaction. Closes, * however, are not transaction-protected, so we have to * handle them here. * * Note that it should be unsafe for the master to do a close * of a file that was opened in an active transaction, so we * should be guaranteed to get the ordering right. */ memcpy(&txnid, (u_int8_t *)rec->data + SSZ(__dbreg_register_args, txnid), sizeof(u_int32_t)); if (txnid == TXN_INVALID) ret = __db_dispatch(dbenv, dbenv->recover_dtab, dbenv->recover_dtab_size, rec, &rp->lsn, DB_TXN_APPLY, NULL); break; case DB___txn_regop: /* * If an application is doing app-specific recovery * and acquires locks while applying a transaction, * it can deadlock. Any other locks held by this * thread should have been discarded in the * __rep_process_txn error path, so if we simply * retry, we should eventually succeed. */ do { ret = 0; if (!F_ISSET(db_rep, DBREP_OPENFILES)) { ret = __txn_openfiles(dbenv, NULL, 1); F_SET(db_rep, DBREP_OPENFILES); } if (ret == 0) ret = __rep_process_txn(dbenv, rec); } while (ret == DB_LOCK_DEADLOCK); /* Now flush the log unless we're running TXN_NOSYNC. */ if (ret == 0 && !F_ISSET(dbenv, DB_ENV_TXN_NOSYNC)) ret = __log_flush(dbenv, NULL); if (ret != 0) { __db_err(dbenv, "Error processing txn [%lu][%lu]", (u_long)rp->lsn.file, (u_long)rp->lsn.offset); ret = __db_panic(dbenv, ret); } break; case DB___txn_xa_regop: ret = __log_flush(dbenv, NULL); break; case DB___txn_ckp: /* * We do not want to hold the db_rep->db_mutexp * mutex while syncing the mpool, so if we get * a checkpoint record that we are supposed to * process, we add it to the __db.rep.db, do * the memp_sync and then go back and process * it later, when the sync has finished. If * this record is already in the table, then * some other thread will process it, so simply * return REP_NOTPERM; */ memset(&key_dbt, 0, sizeof(key_dbt)); key_dbt.data = rp; key_dbt.size = sizeof(*rp); /* * We want to put this record into the tmp DB only if * it doesn't exist, so use DB_NOOVERWRITE. */ ret = __db_put(dbp, NULL, &key_dbt, rec, DB_NOOVERWRITE); if (ret == DB_KEYEXIST) { if (ret_lsnp != NULL) *ret_lsnp = rp->lsn; ret = DB_REP_NOTPERM; } if (ret != 0) break; /* * Now, do the checkpoint. Regardless of * whether the checkpoint succeeds or not, * we need to remove the record we just put * in the temporary database. If the * checkpoint failed, return an error. We * will act like we never received the * checkpoint. */ if ((ret = __rep_do_ckp(dbenv, rec, rp)) == 0) ret = __log_rep_put(dbenv, &rp->lsn, rec); if ((t_ret = __rep_remfirst(dbenv, &control_dbt, &rec_dbt)) != 0 && ret == 0) ret = t_ret; break; default: break; } out: if (ret == 0 && F_ISSET(rp, DB_LOG_PERM)) *ret_lsnp = rp->lsn; if (control_dbt.data != NULL) __os_ufree(dbenv, control_dbt.data); if (rec_dbt.data != NULL) __os_ufree(dbenv, rec_dbt.data); return (ret); } /* * __rep_resend_req -- * We might have dropped a message, we need to resend our request. * The request we send is dependent on what recovery state we're in. * The caller holds no locks. */ static int __rep_resend_req(dbenv, eid) DB_ENV *dbenv; int eid; { DB_LOG *dblp; DB_LSN lsn; DB_REP *db_rep; LOG *lp; REP *rep; int ret; u_int32_t repflags; ret = 0; db_rep = dbenv->rep_handle; rep = db_rep->region; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; repflags = rep->flags; if (FLD_ISSET(repflags, REP_F_RECOVER_VERIFY)) { MUTEX_LOCK(dbenv, db_rep->db_mutexp); lsn = lp->verify_lsn; MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); if (!IS_ZERO_LSN(lsn)) (void)__rep_send_message(dbenv, eid, REP_VERIFY_REQ, &lsn, NULL, 0); goto out; } else if (FLD_ISSET(repflags, REP_F_RECOVER_UPDATE)) { (void)__rep_send_message(dbenv, eid, REP_UPDATE_REQ, NULL, NULL, 0); } else if (FLD_ISSET(repflags, REP_F_RECOVER_PAGE)) { MUTEX_LOCK(dbenv, db_rep->rep_mutexp); ret = __rep_pggap_req(dbenv, rep, NULL, 0); MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); } else if (FLD_ISSET(repflags, REP_F_RECOVER_LOG)) { MUTEX_LOCK(dbenv, db_rep->db_mutexp); __rep_loggap_req(dbenv, rep, NULL, 0); MUTEX_UNLOCK(dbenv, db_rep->db_mutexp); } out: return (ret); } /* * __rep_check_doreq -- * PUBLIC: int __rep_check_doreq __P((DB_ENV *, REP *)); * * Check if we need to send another request. If so, compare with * the request limits the user might have set. This assumes the * caller holds the db_rep->db_mutexp mutex. Returns 1 if a request * needs to be made, and 0 if it does not. */ int __rep_check_doreq(dbenv, rep) DB_ENV *dbenv; REP *rep; { DB_LOG *dblp; LOG *lp; int req; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; req = ++lp->rcvd_recs >= lp->wait_recs; if (req) { lp->wait_recs *= 2; if (lp->wait_recs > rep->max_gap) lp->wait_recs = rep->max_gap; lp->rcvd_recs = 0; } return (req); } /* * __rep_lockout -- * PUBLIC: void __rep_lockout __P((DB_ENV *, DB_REP *, REP *, u_int32_t)); * * Coordinate with other threads in the library and active txns so * that we can run single-threaded, for recovery or internal backup. * Assumes the caller holds rep_mutexp. */ void __rep_lockout(dbenv, db_rep, rep, msg_th) DB_ENV *dbenv; DB_REP *db_rep; REP *rep; u_int32_t msg_th; { int wait_cnt; /* Phase 1: set REP_F_READY and wait for op_cnt to go to 0. */ F_SET(rep, REP_F_READY); for (wait_cnt = 0; rep->op_cnt != 0;) { MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); __os_sleep(dbenv, 1, 0); #ifdef DIAGNOSTIC if (++wait_cnt % 60 == 0) __db_err(dbenv, "Waiting for txn_cnt to run replication recovery/backup for %d minutes", wait_cnt / 60); #endif MUTEX_LOCK(dbenv, db_rep->rep_mutexp); } /* * Phase 2: set in_recovery and wait for handle count to go * to 0 and for the number of threads in __rep_process_message * to go to 1 (us). */ rep->in_recovery = 1; for (wait_cnt = 0; rep->handle_cnt != 0 || rep->msg_th > msg_th;) { MUTEX_UNLOCK(dbenv, db_rep->rep_mutexp); __os_sleep(dbenv, 1, 0); #ifdef DIAGNOSTIC if (++wait_cnt % 60 == 0) __db_err(dbenv, "Waiting for handle count to run replication recovery/backup for %d minutes", wait_cnt / 60); #endif MUTEX_LOCK(dbenv, db_rep->rep_mutexp); } }