/*- * See the file LICENSE for redistribution information. * * Copyright (c) 2001,2007 Oracle. All rights reserved. * * $Id: rep_record.c,v 12.108 2007/07/10 15:40:16 bostic Exp $ */ #include "db_config.h" #include "db_int.h" #include "dbinc/db_page.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_collect_txn __P((DB_ENV *, DB_LSN *, LSN_COLLECTION *)); static int __rep_do_ckp __P((DB_ENV *, DBT *, REP_CONTROL *)); static int __rep_fire_newmaster __P((DB_ENV *, u_int32_t, int)); static int __rep_fire_startupdone __P((DB_ENV *, u_int32_t, int)); 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 *, DBT *)); static int __rep_process_rec __P((DB_ENV *, REP_CONTROL *, DBT *, db_timespec *, DB_LSN *)); static int __rep_remfirst __P((DB_ENV *, DBT *, DBT *)); static int __rep_skip_msg __P((DB_ENV *, REP *, int, u_int32_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, \ (dbenv, "Master record received on client")); \ REP_PRINT_MESSAGE(dbenv, \ eid, rp, "rep_process_message", 0); \ ret = EINVAL; \ goto errlock; \ } \ } while (0) #define CLIENT_ONLY(rep, rp) do { \ if (!F_ISSET(rep, REP_F_CLIENT)) { \ RPRINT(dbenv, \ (dbenv, "Client record received on master")); \ /* \ * Only broadcast DUPMASTER if leases are not \ * in effect. If I am an old master, using \ * leases and I get a newer message, my leases \ * had better all be expired. \ */ \ if (IS_USING_LEASES(dbenv)) \ DB_ASSERT(dbenv, \ __rep_lease_check(dbenv, 0) == \ DB_REP_LEASE_EXPIRED); \ else { \ REP_PRINT_MESSAGE(dbenv, \ eid, rp, "rep_process_message", 0); \ (void)__rep_send_message(dbenv, DB_EID_BROADCAST, \ REP_DUPMASTER, NULL, NULL, 0, 0); \ } \ ret = DB_REP_DUPMASTER; \ goto errlock; \ } \ } while (0) /* * If a client is attempting to service a request it does not have, * call rep_skip_msg to skip this message and force a rerequest to the * sender. We don't hold the mutex for the stats and may miscount. */ #define CLIENT_REREQ do { \ if (F_ISSET(rep, REP_F_CLIENT)) { \ STAT(rep->stat.st_client_svc_req++); \ if (ret == DB_NOTFOUND) { \ STAT(rep->stat.st_client_svc_miss++); \ ret = __rep_skip_msg(dbenv, rep, eid, rp->rectype);\ } \ } \ } while (0) #define MASTER_UPDATE(dbenv, renv) do { \ REP_SYSTEM_LOCK(dbenv); \ F_SET((renv), DB_REGENV_REPLOCKED); \ (void)time(&(renv)->op_timestamp); \ REP_SYSTEM_UNLOCK(dbenv); \ } while (0) #define RECOVERING_SKIP do { \ if (IS_REP_CLIENT(dbenv) && recovering) { \ /* Not holding region mutex, may miscount */ \ STAT(rep->stat.st_msgs_recover++); \ ret = __rep_skip_msg(dbenv, rep, eid, rp->rectype); \ goto errlock; \ } \ } while (0) /* * 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 we are actively delaying a sync-up, we also skip * all incoming log records until the application requests sync-up. */ #define RECOVERING_LOG_SKIP do { \ if (F_ISSET(rep, REP_F_DELAY) || \ rep->master_id == DB_EID_INVALID || \ (recovering && \ (!F_ISSET(rep, REP_F_RECOVER_LOG) || \ LOG_COMPARE(&rp->lsn, &rep->last_lsn) > 0))) { \ /* Not holding region mutex, may miscount */ \ STAT(rep->stat.st_msgs_recover++); \ ret = __rep_skip_msg(dbenv, rep, eid, rp->rectype); \ goto errlock; \ } \ } 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 * eid: the environment id of the sender of the message; * 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, eid, ret_lsnp) DB_ENV *dbenv; DBT *control, *rec; int eid; DB_LSN *ret_lsnp; { DB_LOG *dblp; DB_LSN last_lsn, lsn; DB_REP *db_rep; DB_THREAD_INFO *ip; DBT data_dbt; LOG *lp; REGENV *renv; REGINFO *infop; REP *rep; REP_CONTROL *rp, tmprp; REP_OLD_CONTROL *orp; u_int32_t egen, gen; int cmp, do_sync, recovering, ret; time_t savetime; PANIC_CHECK(dbenv); ENV_REQUIRES_CONFIG_XX( dbenv, rep_handle, "DB_ENV->rep_process_message", DB_INIT_REP); /* Control argument must be non-Null. */ if (control == NULL || control->size == 0) { __db_errx(dbenv, "DB_ENV->rep_process_message: control argument must be specified"); return (EINVAL); } if (!IS_REP_MASTER(dbenv) && !IS_REP_CLIENT(dbenv)) { __db_errx(dbenv, "Environment not configured as replication master or client"); return (EINVAL); } if ((ret = __dbt_usercopy(dbenv, control)) != 0 || (ret = __dbt_usercopy(dbenv, rec)) != 0) { __dbt_userfree(dbenv, control, rec, NULL); __db_errx(dbenv, "DB_ENV->rep_process_message: error retrieving DBT contents"); return ret; } ret = 0; do_sync = 0; db_rep = dbenv->rep_handle; rep = db_rep->region; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; infop = dbenv->reginfo; renv = infop->primary; /* * Casting this to REP_OLD_CONTROL is just kind of stylistic: the * rep_version field of course has to be in the same offset in all * versions in order for this to work. */ if (((REP_OLD_CONTROL *)control->data)->rep_version <= DB_REPVERSION_45) { orp = (REP_OLD_CONTROL *)control->data; tmprp.rep_version = orp->rep_version; tmprp.log_version = orp->log_version; tmprp.lsn = orp->lsn; tmprp.rectype = orp->rectype; tmprp.gen = orp->gen; tmprp.flags = orp->flags; timespecclear(&tmprp.msg_time); rp = (REP_CONTROL *)&tmprp; } else rp = (REP_CONTROL *)control->data; if (ret_lsnp != NULL) ZERO_LSN(*ret_lsnp); ENV_ENTER(dbenv, ip); REP_PRINT_MESSAGE(dbenv, eid, rp, "rep_process_message", 0); /* * Acquire the replication lock. */ REP_SYSTEM_LOCK(dbenv); if (F_ISSET(rep, REP_F_READY_MSG)) { /* * If we're racing with a thread in rep_start, then * just ignore the message and return. */ RPRINT(dbenv, (dbenv, "Racing replication msg lockout, ignore message.")); if (F_ISSET(rp, REPCTL_PERM)) ret = DB_REP_IGNORE; REP_SYSTEM_UNLOCK(dbenv); /* * If another client has sent a c2c request to us, it may be a * long time before it resends the request (due to its dual data * streams avoidance heuristic); let it know we can't serve the * request just now. */ if (F_ISSET(rep, REP_F_CLIENT) && REP_MSG_REQ(rp->rectype)) { STAT(rep->stat.st_client_svc_req++); STAT(rep->stat.st_client_svc_miss++); (void)__rep_send_message(dbenv, eid, REP_REREQUEST, NULL, NULL, 0, 0); } goto out; } rep->msg_th++; gen = rep->gen; recovering = F_ISSET(rep, REP_F_RECOVER_MASK); savetime = renv->rep_timestamp; STAT(rep->stat.st_msgs_processed++); REP_SYSTEM_UNLOCK(dbenv); /* * Check the version number for both rep and log. If it is * an old version we support, convert it. Otherwise complain. */ if (rp->rep_version < DB_REPVERSION) { RPRINT(dbenv, (dbenv, "Received record %lu with old rep version %lu", (u_long)rp->rectype, (u_long)rp->rep_version)); rp->rectype = __rep_msg_from_old(rp->rep_version, rp->rectype); /* * We should have a valid new record type for all the old * versions. */ DB_ASSERT(dbenv, rp->rectype != REP_INVALID); RPRINT(dbenv, (dbenv, "Converted to record %lu with old rep version %lu", (u_long)rp->rectype, (u_long)rp->rep_version)); } else if (rp->rep_version > DB_REPVERSION) { __db_errx(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) { RPRINT(dbenv, (dbenv, "Received record %lu with old log version %lu", (u_long)rp->rectype, (u_long)rp->log_version)); } else if (rp->log_version > DB_LOGVERSION) { __db_errx(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. */ STAT(rep->stat.st_msgs_badgen++); if (F_ISSET(rp, REPCTL_PERM)) ret = DB_REP_IGNORE; 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)) { STAT(rep->stat.st_dupmasters++); ret = DB_REP_DUPMASTER; /* * Only broadcast DUPMASTER if leases are not * in effect. If I am an old master, using * leases and I get a newer message, my leases * had better all be expired. */ if (IS_USING_LEASES(dbenv)) DB_ASSERT(dbenv, __rep_lease_check(dbenv, 0) == DB_REP_LEASE_EXPIRED); else if (rp->rectype != REP_DUPMASTER) (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_DUPMASTER, NULL, NULL, 0, 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) { REP_SYSTEM_LOCK(dbenv); RPRINT(dbenv, (dbenv, "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. */ REP_SYSTEM_UNLOCK(dbenv); if (rp->rectype == REP_ALIVE) (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_MASTER_REQ, NULL, NULL, 0, 0); } else if (rp->rectype != REP_NEWMASTER) { /* * Ignore this message, retransmit if needed. */ if (__rep_check_doreq(dbenv, rep)) (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_MASTER_REQ, NULL, NULL, 0, 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. */ } /* * If the sender is part of an established group, so are we now. */ if (F_ISSET(rp, REPCTL_GROUP_ESTD)) { REP_SYSTEM_LOCK(dbenv); #ifdef DIAGNOSTIC if (!F_ISSET(rep, REP_F_GROUP_ESTD)) RPRINT(dbenv, (dbenv, "I am now part of an established group")); #endif F_SET(rep, REP_F_GROUP_ESTD); REP_SYSTEM_UNLOCK(dbenv); } /* * 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. */ switch (rp->rectype) { case REP_ALIVE: /* * Handle even if we're recovering. */ ANYSITE(rep); egen = *(u_int32_t *)rec->data; REP_SYSTEM_LOCK(dbenv); RPRINT(dbenv, (dbenv, "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. We need to set the * REP_F_EGENUPDATE flag here so that any thread * waiting in rep_elect/rep_wait can distinguish * this situation (and restart its election) from * a current master saying it is still master and * the egen getting incremented on that path. */ __rep_elect_done(dbenv, rep); rep->egen = egen; F_SET(rep, REP_F_EGENUPDATE); } REP_SYSTEM_UNLOCK(dbenv); break; case REP_ALIVE_REQ: /* * Handle even if we're recovering. */ ANYSITE(rep); dblp = dbenv->lg_handle; LOG_SYSTEM_LOCK(dbenv); lsn = ((LOG *)dblp->reginfo.primary)->lsn; LOG_SYSTEM_UNLOCK(dbenv); REP_SYSTEM_LOCK(dbenv); egen = rep->egen; REP_SYSTEM_UNLOCK(dbenv); data_dbt.data = &egen; data_dbt.size = sizeof(egen); (void)__rep_send_message(dbenv, eid, REP_ALIVE, &lsn, &data_dbt, 0, 0); break; case REP_ALL_REQ: RECOVERING_SKIP; ret = __rep_allreq(dbenv, rp, eid); CLIENT_REREQ; break; case REP_BULK_LOG: RECOVERING_LOG_SKIP; CLIENT_ONLY(rep, rp); ret = __rep_bulk_log(dbenv, rp, rec, savetime, ret_lsnp); break; case REP_BULK_PAGE: /* * Handle even if we're recovering. */ CLIENT_ONLY(rep, rp); ret = __rep_bulk_page(dbenv, eid, rp, rec); break; case REP_DUPMASTER: /* * Handle even if we're recovering. */ if (F_ISSET(rep, REP_F_MASTER)) ret = DB_REP_DUPMASTER; break; #ifdef NOTYET case REP_FILE: /* TODO */ CLIENT_ONLY(rep, rp); break; case REP_FILE_REQ: ret = __rep_send_file(dbenv, rec, eid); break; #endif case REP_FILE_FAIL: /* * Handle even if we're recovering. */ CLIENT_ONLY(rep, rp); /* * XXX */ break; case REP_LEASE_GRANT: /* * Handle even if we're recovering. */ MASTER_ONLY(rep, rp); ret = __rep_lease_grant(dbenv, rp, rec, eid); break; case REP_LOG: case REP_LOG_MORE: RECOVERING_LOG_SKIP; CLIENT_ONLY(rep, rp); ret = __rep_log(dbenv, rp, rec, savetime, ret_lsnp); break; case REP_LOG_REQ: RECOVERING_SKIP; if (F_ISSET(rp, REPCTL_INIT)) MASTER_UPDATE(dbenv, renv); ret = __rep_logreq(dbenv, rp, rec, eid); CLIENT_REREQ; break; case REP_NEWSITE: /* * Handle even if we're recovering. */ /* We don't hold the rep mutex, and may miscount. */ STAT(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; LOG_SYSTEM_LOCK(dbenv); lsn = lp->lsn; LOG_SYSTEM_UNLOCK(dbenv); (void)__rep_send_message(dbenv, eid, REP_NEWMASTER, &lsn, NULL, 0, 0); if (IS_USING_LEASES(dbenv)) ret = __rep_lease_refresh(dbenv); } ret = DB_REP_NEWSITE; break; case REP_NEWCLIENT: /* * Handle even if we're recovering. */ /* * 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, 0); ret = DB_REP_NEWSITE; if (F_ISSET(rep, REP_F_CLIENT)) { REP_SYSTEM_LOCK(dbenv); egen = rep->egen; if (eid == rep->master_id) rep->master_id = DB_EID_INVALID; REP_SYSTEM_UNLOCK(dbenv); data_dbt.data = &egen; data_dbt.size = sizeof(egen); (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_ALIVE, &rp->lsn, &data_dbt, 0, 0); break; } /* FALLTHROUGH */ case REP_MASTER_REQ: RECOVERING_SKIP; if (F_ISSET(rep, REP_F_MASTER)) { LOG_SYSTEM_LOCK(dbenv); lsn = lp->lsn; LOG_SYSTEM_UNLOCK(dbenv); (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_NEWMASTER, &lsn, NULL, 0, 0); if (IS_USING_LEASES(dbenv)) ret = __rep_lease_refresh(dbenv); } /* * 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) { REP_SYSTEM_LOCK(dbenv); egen = rep->egen; if (eid == rep->master_id) rep->master_id = DB_EID_INVALID; REP_SYSTEM_UNLOCK(dbenv); data_dbt.data = &egen; data_dbt.size = sizeof(egen); (void)__rep_send_message(dbenv, eid, REP_ALIVE, &rp->lsn, &data_dbt, 0, 0); } break; case REP_NEWFILE: RECOVERING_LOG_SKIP; CLIENT_ONLY(rep, rp); ret = __rep_apply(dbenv, rp, rec, ret_lsnp, NULL, &last_lsn); if (ret == DB_REP_LOGREADY) ret = __rep_logready(dbenv, rep, savetime, &last_lsn); break; case REP_NEWMASTER: /* * Handle even if we're recovering. */ ANYSITE(rep); if (F_ISSET(rep, REP_F_MASTER) && eid != rep->eid) { /* We don't hold the rep mutex, and may miscount. */ STAT(rep->stat.st_dupmasters++); ret = DB_REP_DUPMASTER; if (IS_USING_LEASES(dbenv)) DB_ASSERT(dbenv, __rep_lease_check(dbenv, 0) == DB_REP_LEASE_EXPIRED); else (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_DUPMASTER, NULL, NULL, 0, 0); break; } if ((ret = __rep_new_master(dbenv, rp, eid)) == DB_REP_NEWMASTER) ret = __rep_fire_newmaster(dbenv, rp->gen, eid); break; case REP_PAGE: case REP_PAGE_MORE: /* * Handle even if we're recovering. */ CLIENT_ONLY(rep, rp); ret = __rep_page(dbenv, eid, rp, rec); if (ret == DB_REP_PAGEDONE) ret = 0; break; case REP_PAGE_FAIL: /* * Handle even if we're recovering. */ CLIENT_ONLY(rep, rp); ret = __rep_page_fail(dbenv, eid, rec); break; case REP_PAGE_REQ: RECOVERING_SKIP; MASTER_UPDATE(dbenv, renv); ret = __rep_page_req(dbenv, eid, rec); CLIENT_REREQ; break; case REP_REREQUEST: /* * Handle even if we're recovering. Don't do a master * check. */ CLIENT_ONLY(rep, rp); /* * Don't hold any mutex, may miscount. */ STAT(rep->stat.st_client_rerequests++); ret = __rep_resend_req(dbenv, 1); break; case REP_START_SYNC: RECOVERING_SKIP; MUTEX_LOCK(dbenv, rep->mtx_clientdb); cmp = LOG_COMPARE(&rp->lsn, &lp->ready_lsn); /* * The comparison needs to be <= because the LSN in * the message can be the LSN of the first outstanding * txn, which may be the LSN immediately after the * previous commit. The ready_lsn is the LSN of the * next record expected. In that case, the LSNs * could be equal and the client has the commit and * wants to sync. [SR #15338] */ if (cmp <= 0) { MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); do_sync = 1; } else { STAT(rep->stat.st_startsync_delayed++); /* * There are cases where keeping the first ckp_lsn * LSN is advantageous and cases where keeping * a later LSN is better. If random, earlier * log records are missing, keeping the later * LSN seems to be better. That is what we'll * do for now. */ if (LOG_COMPARE(&rp->lsn, &rep->ckp_lsn) > 0) rep->ckp_lsn = rp->lsn; RPRINT(dbenv, (dbenv, "Delayed START_SYNC memp_sync due to missing records.")); RPRINT(dbenv, (dbenv, "ready LSN [%lu][%lu], ckp_lsn [%lu][%lu]", (u_long)lp->ready_lsn.file, (u_long)lp->ready_lsn.offset, (u_long)rep->ckp_lsn.file, (u_long)rep->ckp_lsn.offset)); MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); } break; case REP_UPDATE: /* * Handle even if we're recovering. */ CLIENT_ONLY(rep, rp); ret = __rep_update_setup(dbenv, eid, rp, rec); break; case REP_UPDATE_REQ: /* * Handle even if we're recovering. */ MASTER_ONLY(rep, rp); infop = dbenv->reginfo; renv = infop->primary; MASTER_UPDATE(dbenv, renv); ret = __rep_update_req(dbenv, eid); break; case REP_VERIFY: if (recovering) { MUTEX_LOCK(dbenv, rep->mtx_clientdb); cmp = LOG_COMPARE(&lp->verify_lsn, &rp->lsn); MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); /* * If this is not the verify record I want, skip it. */ if (cmp != 0) { ret = __rep_skip_msg( dbenv, rep, eid, rp->rectype); break; } } CLIENT_ONLY(rep, rp); ret = __rep_verify(dbenv, rp, rec, eid, savetime); break; case REP_VERIFY_FAIL: /* * Handle even if we're recovering. */ CLIENT_ONLY(rep, rp); ret = __rep_verify_fail(dbenv, rp, eid); break; case REP_VERIFY_REQ: RECOVERING_SKIP; ret = __rep_verify_req(dbenv, rp, eid); CLIENT_REREQ; break; case REP_VOTE1: /* * Handle even if we're recovering. */ ret = __rep_vote1(dbenv, rp, rec, eid); break; case REP_VOTE2: /* * Handle even if we're recovering. */ ret = __rep_vote2(dbenv, rec, eid); break; default: __db_errx(dbenv, "DB_ENV->rep_process_message: unknown replication message: type %lu", (u_long)rp->rectype); ret = EINVAL; break; } errlock: REP_SYSTEM_LOCK(dbenv); rep->msg_th--; REP_SYSTEM_UNLOCK(dbenv); if (do_sync) { MUTEX_LOCK(dbenv, rep->mtx_ckp); lsn = rp->lsn; /* * This is the REP_START_SYNC sync, and so we permit it to be * interrupted. */ ret = __memp_sync( dbenv, DB_SYNC_CHECKPOINT | DB_SYNC_INTERRUPT_OK, &lsn); MUTEX_UNLOCK(dbenv, rep->mtx_ckp); RPRINT(dbenv, (dbenv, "ALIVE: Completed sync [%lu][%lu]", (u_long)lsn.file, (u_long)lsn.offset)); } out: if (ret == 0 && F_ISSET(rp, REPCTL_PERM)) { if (ret_lsnp != NULL) *ret_lsnp = rp->lsn; ret = DB_REP_NOTPERM; } __dbt_userfree(dbenv, control, rec, NULL); ENV_LEAVE(dbenv, ip); 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. * * PUBLIC: int __rep_apply __P((DB_ENV *, REP_CONTROL *, * PUBLIC: DBT *, DB_LSN *, int *, DB_LSN *)); */ int __rep_apply(dbenv, rp, rec, ret_lsnp, is_dupp, last_lsnp) DB_ENV *dbenv; REP_CONTROL *rp; DBT *rec; DB_LSN *ret_lsnp; int *is_dupp; DB_LSN *last_lsnp; { DB_REP *db_rep; DBT control_dbt, key_dbt; DBT rec_dbt; DB *dbp; DB_LOG *dblp; DB_LSN max_lsn, save_lsn; LOG *lp; REP *rep; db_timespec max_ts; u_int32_t gen; int cmp, event, master, ret, set_apply, t_ret; COMPQUIET(gen, 0); COMPQUIET(master, DB_EID_INVALID); db_rep = dbenv->rep_handle; rep = db_rep->region; event = ret = set_apply = 0; memset(&control_dbt, 0, sizeof(control_dbt)); memset(&rec_dbt, 0, sizeof(rec_dbt)); ZERO_LSN(max_lsn); timespecclear(&max_ts); cmp = -2; /* OOB value that LOG_COMPARE can't return. */ dblp = dbenv->lg_handle; MUTEX_LOCK(dbenv, rep->mtx_clientdb); /* * Lazily open the temp db. Always set the startup flag to 0 * because it was initialized from rep_start. */ if (db_rep->rep_db == NULL && (ret = __rep_client_dbinit(dbenv, 0, REP_DB)) != 0) { MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); goto out; } dbp = db_rep->rep_db; lp = dblp->reginfo.primary; REP_SYSTEM_LOCK(dbenv); if (F_ISSET(rep, REP_F_RECOVER_LOG) && LOG_COMPARE(&lp->ready_lsn, &rep->first_lsn) < 0) lp->ready_lsn = rep->first_lsn; cmp = LOG_COMPARE(&rp->lsn, &lp->ready_lsn); /* * If we are going to skip or process any message other * than a duplicate, make note of it if we're in an * election so that the election can rerequest proactively. */ if (F_ISSET(rep, REP_F_READY_APPLY) && cmp >= 0) F_SET(rep, REP_F_SKIPPED_APPLY); /* * If we're in the middle of processing a NEWFILE, we've dropped * the mutex and if this matches it is a duplicate record. We * do not want this call taking the "matching" code below because * we may then process later records in the temp db and the * original NEWFILE may not have the log file ready. It will * process those temp db items when it completes. */ if (F_ISSET(rep, REP_F_NEWFILE) && cmp == 0) cmp = -1; if (cmp == 0) { /* * If we are in an election (i.e. we've sent a vote * with an LSN in it), then we drop the next record * we're expecting. When we find a master, we'll * either go into sync, or if it was an existing * master, rerequest this one record (later records * are accumulating in the temp db). * * We can simply return here, and rep_process_message * will set NOTPERM if necessary for this record. */ if (F_ISSET(rep, REP_F_READY_APPLY)) { /* * We will simply return now. All special return * processing should be ignored because the special * values are just initialized. Variables like * max_lsn are still 0. */ RPRINT(dbenv, (dbenv, "rep_apply: In election. Ignoring [%lu][%lu]", (u_long)rp->lsn.file, (u_long)rp->lsn.offset)); REP_SYSTEM_UNLOCK(dbenv); MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); goto out; } rep->apply_th++; set_apply = 1; RPRINT(dbenv, (dbenv, "rep_apply: Set apply_th %d", rep->apply_th)); REP_SYSTEM_UNLOCK(dbenv); if ((ret = __rep_process_rec(dbenv, rp, rec, &max_ts, &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; ZERO_LSN(lp->max_wait_lsn); 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: 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, &max_ts, &max_lsn)) != 0) goto err; --rep->stat.st_log_queued; /* * Since we just filled a gap in the log stream, and * we're writing subsequent records to the log, we want * to use rcvd_recs and wait_recs so that we will * request the next gap if we end up with a gap and * a lot of records still in the temp db, but not * request if it is near the end of the temp db and * likely to arrive on its own shortly. We want to * avoid requesting the record in that case. Also * reset max_wait_lsn because the next gap is a * fresh gap. */ lp->rcvd_recs = rep->stat.st_log_queued; lp->wait_recs = rep->request_gap; if ((ret = __rep_getnext(dbenv)) == DB_NOTFOUND) { lp->rcvd_recs = 0; 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 we * filled a gap we keep a count of how many other * records are in the temp database and if we should * request the next gap at this time. */ if (__rep_check_doreq(dbenv, rep) && (ret = __rep_loggap_req(dbenv, rep, &rp->lsn, 0)) != 0) goto err; } 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. */ REP_SYSTEM_UNLOCK(dbenv); 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) && (ret = __rep_loggap_req(dbenv, rep, &rp->lsn, 0) != 0)) goto err; ret = __db_put(dbp, NULL, &key_dbt, rec, DB_NOOVERWRITE); if (ret == 0) { rep->stat.st_log_queued++; #ifdef HAVE_STATISTICS STAT(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; #endif } 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, REPCTL_PERM)) { max_lsn = rp->lsn; ret = DB_REP_NOTPERM; } goto done; } else { STAT(rep->stat.st_log_duplicated++); REP_SYSTEM_UNLOCK(dbenv); if (is_dupp != NULL) *is_dupp = 1; if (F_ISSET(rp, REPCTL_PERM)) max_lsn = lp->max_perm_lsn; /* * We check REPCTL_LEASE here, because this client may * have leases configured but the master may not (especially * in a mixed version group. If the master has leases * configured, all clients must also. */ if (IS_USING_LEASES(dbenv) && F_ISSET(rp, REPCTL_LEASE) && timespecisset(&rp->msg_time)) { if (timespeccmp(&rp->msg_time, &lp->max_lease_ts, >)) max_ts = rp->msg_time; else max_ts = lp->max_lease_ts; } 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: /* * In case of a race, to make sure only one thread can get * DB_REP_LOGREADY, zero out rep->last_lsn to show that we've gotten to * this point. */ REP_SYSTEM_LOCK(dbenv); if (ret == 0 && F_ISSET(rep, REP_F_RECOVER_LOG) && !IS_ZERO_LSN(rep->last_lsn) && LOG_COMPARE(&lp->ready_lsn, &rep->last_lsn) >= 0) { *last_lsnp = max_lsn; ZERO_LSN(rep->last_lsn); ZERO_LSN(max_lsn); ret = DB_REP_LOGREADY; } /* * Only decrement if we were actually applying log records. * We do not care if we processed a dup record or put one * in the temp db. */ if (set_apply) { rep->apply_th--; RPRINT(dbenv, (dbenv, "rep_apply: Decrement apply_th %d", rep->apply_th)); } 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(dbenv, LOG_COMPARE(&max_lsn, &lp->max_perm_lsn) >= 0); lp->max_perm_lsn = max_lsn; } /* * Start-up is complete when we process (or have already processed) up * to the end of the replication group's log. In case we miss that * message, as a back-up, we also recognize start-up completion when we * actually process a live log record. Having cmp==0 here (with a good * "ret" value) implies we actually processed the record. */ if ((ret == 0 || ret == DB_REP_ISPERM) && rep->stat.st_startup_complete == 0 && ((cmp <= 0 && F_ISSET(rp, REPCTL_LOG_END)) || (cmp == 0 && !F_ISSET(rp, REPCTL_RESEND)))) { rep->stat.st_startup_complete = 1; event = 1; gen = rep->gen; master = rep->master_id; } REP_SYSTEM_UNLOCK(dbenv); /* * If we've processed beyond the needed LSN for a pending * start sync, start it now. We can compare >= here * because ready_lsn is the next record we expect. * Since ckp_lsn can point to the last commit record itself, * but if it does and ready_lsn == commit (i.e. we haven't * written the commit yet), we can still start to sync * because we're guaranteed no additional buffers can * be dirtied. */ if (!IS_ZERO_LSN(rep->ckp_lsn) && LOG_COMPARE(&lp->ready_lsn, &rep->ckp_lsn) >= 0) { save_lsn = rep->ckp_lsn; ZERO_LSN(rep->ckp_lsn); } else ZERO_LSN(save_lsn); /* * If this is a perm record, we are using leases, update the lease * grant. We must hold the clientdb mutex. We must not hold * the region mutex because rep_update_grant will acquire it. */ if (ret == DB_REP_ISPERM && IS_USING_LEASES(dbenv) && timespecisset(&max_ts)) { if ((ret = __rep_update_grant(dbenv, &max_ts)) != 0) return (ret); if (timespeccmp(&max_ts, &lp->max_lease_ts, >)) lp->max_lease_ts = max_ts; } MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); if (!IS_ZERO_LSN(save_lsn)) { /* * Now call memp_sync holding only the ckp mutex. */ MUTEX_LOCK(dbenv, rep->mtx_ckp); RPRINT(dbenv, (dbenv, "Starting delayed __memp_sync call [%lu][%lu]", (u_long)save_lsn.file, (u_long)save_lsn.offset)); ret = __memp_sync(dbenv, DB_SYNC_CHECKPOINT, &save_lsn); MUTEX_UNLOCK(dbenv, rep->mtx_ckp); } if (event) { RPRINT(dbenv, (dbenv, "Start-up is done [%lu][%lu]", (u_long)rp->lsn.file, (u_long)rp->lsn.offset)); if ((t_ret = __rep_fire_startupdone(dbenv, gen, master)) != 0) { DB_ASSERT(dbenv, ret == 0 || ret == DB_REP_ISPERM); /* Failure trumps either of those values. */ ret = t_ret; goto out; } } 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); out: switch (ret) { case 0: break; case DB_REP_ISPERM: RPRINT(dbenv, (dbenv, "Returning ISPERM [%lu][%lu], cmp = %d", (u_long)max_lsn.file, (u_long)max_lsn.offset, cmp)); break; case DB_REP_LOGREADY: RPRINT(dbenv, (dbenv, "Returning LOGREADY up to [%lu][%lu], cmp = %d", (u_long)last_lsnp->file, (u_long)last_lsnp->offset, cmp)); break; case DB_REP_NOTPERM: if (!F_ISSET(rep, REP_F_RECOVER_LOG) && !IS_ZERO_LSN(max_lsn) && ret_lsnp != NULL) *ret_lsnp = max_lsn; RPRINT(dbenv, (dbenv, "Returning NOTPERM [%lu][%lu], cmp = %d", (u_long)max_lsn.file, (u_long)max_lsn.offset, cmp)); break; default: RPRINT(dbenv, (dbenv, "Returning %d [%lu][%lu], cmp = %d", ret, (u_long)max_lsn.file, (u_long)max_lsn.offset, cmp)); break; } 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_LOCKER *locker; DB_LOCKREQ req, *lvp; DB_LOGC *logc; DB_LSN prev_lsn, *lsnp; DB_REP *db_rep; DB_TXNHEAD *txninfo; LSN_COLLECTION lc; REP *rep; __txn_regop_args *txn_args; __txn_regop_42_args *txn42_args; __txn_xa_regop_args *prep_args; u_int32_t rectype; u_int i; int ret, t_ret; db_rep = dbenv->rep_handle; rep = db_rep->region; logc = NULL; txn_args = NULL; txn42_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 (rep->version >= DB_REPVERSION_44) { 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 { if ((ret = __txn_regop_42_read(dbenv, rec->data, &txn42_args)) != 0) return (ret); if (txn42_args->opcode != TXN_COMMIT) { __os_free(dbenv, txn42_args); return (0); } prev_lsn = txn42_args->prev_lsn; lock_dbt = &txn42_args->locks; } } else { /* We're a prepare. */ DB_ASSERT(dbenv, 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, NULL, &locker)) != 0) goto err1; if ((ret = __lock_get_list(dbenv, locker, 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 = __logc_get(logc, lsnp, &data_dbt, DB_SET)) != 0) { __db_errx(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_errx(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, locker, 0, &req, 1, &lvp)) != 0 && ret == 0) ret = t_ret; if ((t_ret = __lock_id_free(dbenv, locker)) != 0 && ret == 0) ret = t_ret; err1: if (txn_args != NULL) __os_free(dbenv, txn_args); if (txn42_args != NULL) __os_free(dbenv, txn42_args); if (prep_args != NULL) __os_free(dbenv, prep_args); if (lc.array != NULL) __os_free(dbenv, lc.array); if (logc != NULL && (t_ret = __logc_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); #ifdef HAVE_STATISTICS if (ret == 0) /* * We don't hold the rep mutex, and could miscount if we race. */ rep->stat.st_txns_applied++; #endif 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 = __logc_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_errx(dbenv, "collect failed at: [%lu][%lu]", (u_long)lsnp->file, (u_long)lsnp->offset); err: if ((t_ret = __logc_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. Assume caller hold mtx_clientdb. */ static int __rep_newfile(dbenv, rc, rec) DB_ENV *dbenv; REP_CONTROL *rc; DBT *rec; { DB_LOG *dblp; DB_LSN tmplsn; DB_REP *db_rep; LOG *lp; REP *rep; u_int32_t version; int ret; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; db_rep = dbenv->rep_handle; rep = db_rep->region; /* * If a newfile is already in progress, just ignore. */ if (F_ISSET(rep, REP_F_NEWFILE)) return (0); if (rc->lsn.file + 1 > lp->ready_lsn.file) { if (rec == NULL || rec->size == 0) { RPRINT(dbenv, (dbenv, "Rep_newfile: Old-style NEWFILE msg. Use control msg log version: %lu", (u_long) rc->log_version)); version = rc->log_version; } else version = *(u_int32_t *)rec->data; RPRINT(dbenv, (dbenv, "Rep_newfile: File %lu vers %lu", (u_long)rc->lsn.file + 1, (u_long)version)); /* * We drop the mtx_clientdb mutex during * the file operation, and then reacquire it when * we're done. We avoid colliding with new incoming * log records because lp->ready_lsn is not getting * updated and there is no real log record at this * ready_lsn. We avoid colliding with a duplicate * NEWFILE message by setting an in-progress flag. */ REP_SYSTEM_LOCK(dbenv); F_SET(rep, REP_F_NEWFILE); REP_SYSTEM_UNLOCK(dbenv); MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); LOG_SYSTEM_LOCK(dbenv); ret = __log_newfile(dblp, &tmplsn, 0, version); LOG_SYSTEM_UNLOCK(dbenv); MUTEX_LOCK(dbenv, rep->mtx_clientdb); REP_SYSTEM_LOCK(dbenv); F_CLR(rep, REP_F_NEWFILE); REP_SYSTEM_UNLOCK(dbenv); if (ret == 0) lp->ready_lsn = tmplsn; return (ret); } else /* We've already applied this NEWFILE. Just ignore it. */ return (0); } /* * __rep_do_ckp -- * Perform the memp_sync necessary for this checkpoint without holding the * REP->mtx_clientdb. Callers of this function must hold REP->mtx_clientdb * and must not be holding the region mutex. */ static int __rep_do_ckp(dbenv, rec, rp) DB_ENV *dbenv; DBT *rec; REP_CONTROL *rp; { __txn_ckp_args *ckp_args; DB_LSN ckp_lsn; REP *rep; int ret; /* Crack the log record and extract the checkpoint LSN. */ if ((ret = __txn_ckp_read(dbenv, rec->data, &ckp_args)) != 0) return (ret); ckp_lsn = ckp_args->ckp_lsn; __os_free(dbenv, ckp_args); rep = dbenv->rep_handle->region; MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); DB_TEST_WAIT(dbenv, dbenv->test_check); /* * Sync the memory pool. * * This is the real PERM lock record/ckp. We cannot return ISPERM * if we haven't truly completed the checkpoint, so we don't allow * this call to be interrupted. * * We may be overlapping our log record with an in-progress startsync * of this checkpoint; suppress the max_write settings on any running * cache-flush operation so it completes quickly. */ (void)__memp_set_config(dbenv, DB_MEMP_SUPPRESS_WRITE, 1); MUTEX_LOCK(dbenv, rep->mtx_ckp); ret = __memp_sync(dbenv, DB_SYNC_CHECKPOINT, &ckp_lsn); MUTEX_UNLOCK(dbenv, rep->mtx_ckp); (void)__memp_set_config(dbenv, DB_MEMP_SUPPRESS_WRITE, 0); /* Update the last_ckp in the txn region. */ if (ret == 0) ret = __txn_updateckp(dbenv, &rp->lsn); else { __db_errx(dbenv, "Error syncing ckp [%lu][%lu]", (u_long)ckp_lsn.file, (u_long)ckp_lsn.offset); ret = __db_panic(dbenv, ret); } MUTEX_LOCK(dbenv, rep->mtx_clientdb); 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; 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 = __dbc_get(dbc, cntrl, rec, DB_RMW | DB_FIRST)) == 0) ret = __dbc_del(dbc, 0); if ((t_ret = __dbc_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 = __dbc_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 = __dbc_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, ret_tsp, ret_lsnp) DB_ENV *dbenv; REP_CONTROL *rp; DBT *rec; db_timespec *ret_tsp; DB_LSN *ret_lsnp; { DB *dbp; DB_REP *db_rep; DBT control_dbt, key_dbt, rec_dbt; REP *rep; u_int32_t rectype, txnid; int ret, t_ret; db_rep = dbenv->rep_handle; rep = db_rep->region; dbp = db_rep->rep_db; ret = 0; if (rp->rectype == REP_NEWFILE) { ret = __rep_newfile(dbenv, rp, rec); return (0); } memcpy(&rectype, rec->data, sizeof(rectype)); 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 (rectype != DB___txn_ckp || F_ISSET(rep, REP_F_RECOVER_LOG)) { if ((ret = __log_rep_put(dbenv, &rp->lsn, rec, 0)) != 0) return (ret); STAT(rep->stat.st_log_records++); if (F_ISSET(rep, REP_F_RECOVER_LOG)) { *ret_lsnp = rp->lsn; goto out; } } switch (rectype) { 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. * * 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. * * !!! * The txn ID is the second 4-byte field of the log record. * We should really be calling __dbreg_register_read() and * working from the __dbreg_register_args structure, but this * is considerably faster and the order of the fields won't * change. */ memcpy(&txnid, (u_int8_t *) rec->data + sizeof(u_int32_t), 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_errx(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); /* * Save the biggest prepared LSN we've seen. */ rep->max_prep_lsn = rp->lsn; RPRINT(dbenv, (dbenv, "process_rec: prepare at [%lu][%lu]", (u_long)rep->max_prep_lsn.file, (u_long)rep->max_prep_lsn.offset)); break; case DB___txn_ckp: /* * We do not want to hold the REP->mtx_clientdb mutex while * syncing the mpool, so if we get a checkpoint record we are * supposed to process, 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, DB_LOG_CHKPNT); if ((t_ret = __rep_remfirst(dbenv, &control_dbt, &rec_dbt)) != 0 && ret == 0) ret = t_ret; /* * If we're successful putting the log record in the * log, flush it for a checkpoint. */ if (ret == 0) ret = __log_flush(dbenv, NULL); break; default: break; } out: if (ret == 0 && F_ISSET(rp, REPCTL_PERM)) *ret_lsnp = rp->lsn; if (IS_USING_LEASES(dbenv) && F_ISSET(rp, REPCTL_LEASE)) *ret_tsp = rp->msg_time; /* * Set ret_lsnp before flushing the log because if the * flush fails, we've still written the record to the * log and the LSN has been entered. */ if (ret == 0 && F_ISSET(rp, REPCTL_FLUSH)) ret = __log_flush(dbenv, NULL); 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. * * PUBLIC: int __rep_resend_req __P((DB_ENV *, int)); */ int __rep_resend_req(dbenv, rereq) DB_ENV *dbenv; int rereq; { DB_LOG *dblp; DB_LSN lsn; DB_REP *db_rep; LOG *lp; REP *rep; int ret; u_int32_t gapflags, repflags; db_rep = dbenv->rep_handle; rep = db_rep->region; dblp = dbenv->lg_handle; lp = dblp->reginfo.primary; ret = 0; repflags = rep->flags; /* * If we are delayed we do not rerequest anything. */ if (FLD_ISSET(repflags, REP_F_DELAY)) return (ret); gapflags = rereq ? REP_GAP_REREQUEST : 0; if (FLD_ISSET(repflags, REP_F_RECOVER_VERIFY)) { MUTEX_LOCK(dbenv, rep->mtx_clientdb); lsn = lp->verify_lsn; MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); if (!IS_ZERO_LSN(lsn)) (void)__rep_send_message(dbenv, rep->master_id, REP_VERIFY_REQ, &lsn, NULL, 0, DB_REP_REREQUEST); } else if (FLD_ISSET(repflags, REP_F_RECOVER_UPDATE)) { /* * UPDATE_REQ only goes to the master. */ (void)__rep_send_message(dbenv, rep->master_id, REP_UPDATE_REQ, NULL, NULL, 0, 0); } else if (FLD_ISSET(repflags, REP_F_RECOVER_PAGE)) { REP_SYSTEM_LOCK(dbenv); ret = __rep_pggap_req(dbenv, rep, NULL, gapflags); REP_SYSTEM_UNLOCK(dbenv); } else { MUTEX_LOCK(dbenv, rep->mtx_clientdb); ret = __rep_loggap_req(dbenv, rep, NULL, gapflags); MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); } 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 REP->mtx_clientdb 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_skip_msg - * * If we're in recovery we want to skip/ignore the message, but * we also need to see if we need to re-request any retransmissions. */ static int __rep_skip_msg(dbenv, rep, eid, rectype) DB_ENV *dbenv; REP *rep; int eid; u_int32_t rectype; { int do_req, ret; ret = 0; /* * If we have a request message from a client then immediately * send a REP_REREQUEST back to that client since we're skipping it. */ if (F_ISSET(rep, REP_F_CLIENT) && REP_MSG_REQ(rectype)) do_req = 1; else { /* Check for need to retransmit. */ MUTEX_LOCK(dbenv, rep->mtx_clientdb); do_req = __rep_check_doreq(dbenv, rep); MUTEX_UNLOCK(dbenv, rep->mtx_clientdb); } /* * Don't respond to a MASTER_REQ with * a MASTER_REQ or REREQUEST. */ if (do_req && rectype != REP_MASTER_REQ) { /* * There are three cases: * 1. If we don't know who the master is, then send MASTER_REQ. * 2. If the message we're skipping came from the master, * then we need to rerequest. * 3. If the message didn't come from a master (i.e. client * to client), then send a rerequest back to the sender so * the sender can rerequest it elsewhere, if we are a client. */ if (rep->master_id == DB_EID_INVALID) /* Case 1. */ (void)__rep_send_message(dbenv, DB_EID_BROADCAST, REP_MASTER_REQ, NULL, NULL, 0, 0); else if (eid == rep->master_id) /* Case 2. */ ret = __rep_resend_req(dbenv, 0); else if (F_ISSET(rep, REP_F_CLIENT)) /* Case 3. */ (void)__rep_send_message(dbenv, eid, REP_REREQUEST, NULL, NULL, 0, 0); } return (ret); } static int __rep_fire_newmaster(dbenv, gen, master) DB_ENV *dbenv; u_int32_t gen; int master; { DB_REP *db_rep; REP *rep; db_rep = dbenv->rep_handle; rep = db_rep->region; REP_EVENT_LOCK(dbenv); /* * The firing of this event should be idempotent with respect to a * particular generation number. */ if (rep->newmaster_event_gen < gen) { __rep_fire_event(dbenv, DB_EVENT_REP_NEWMASTER, &master); rep->newmaster_event_gen = gen; } REP_EVENT_UNLOCK(dbenv); return (0); } static int __rep_fire_startupdone(dbenv, gen, master) DB_ENV *dbenv; u_int32_t gen; int master; { DB_REP *db_rep; REP *rep; db_rep = dbenv->rep_handle; rep = db_rep->region; REP_EVENT_LOCK(dbenv); /* * Usually NEWMASTER will already have been fired. But if not, fire * it here now, to ensure the application receives events in the * expected order. */ if (rep->newmaster_event_gen < gen) { __rep_fire_event(dbenv, DB_EVENT_REP_NEWMASTER, &master); rep->newmaster_event_gen = gen; } /* * Caller already ensures that it only tries to fire STARTUPDONE once * per generation. If we did not want to rely on that, we could add a * simple boolean flag (to the set of data protected by the mtx_event). * The precise meaning of that flag would be "STARTUPDONE has been fired * for the generation value stored in `newmaster_event_gen'". Then the * more accurate test here would be simply to check that flag, and fire * the event (and set the flag) if it were not already set. */ if (rep->newmaster_event_gen == gen) __rep_fire_event(dbenv, DB_EVENT_REP_STARTUPDONE, NULL); REP_EVENT_UNLOCK(dbenv); return (0); }