834 lines
21 KiB
C
834 lines
21 KiB
C
/*-
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* See the file LICENSE for redistribution information.
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*
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* Copyright (c) 1996, 1997, 1998
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* Sleepycat Software. All rights reserved.
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*/
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/*
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* Copyright (c) 1995, 1996
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* The President and Fellows of Harvard University. All rights reserved.
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*
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* This code is derived from software contributed to Berkeley by
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* Margo Seltzer.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include "config.h"
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#ifndef lint
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static const char sccsid[] = "@(#)txn.c 10.58 (Sleepycat) 5/31/98";
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#endif /* not lint */
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#ifndef NO_SYSTEM_INCLUDES
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#include <sys/types.h>
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#include <errno.h>
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#include <string.h>
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#include <time.h>
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#endif
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#include "db_int.h"
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#include "shqueue.h"
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#include "db_page.h"
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#include "db_shash.h"
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#include "txn.h"
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#include "db_dispatch.h"
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#include "lock.h"
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#include "log.h"
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#include "db_am.h"
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#include "common_ext.h"
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static int __txn_check_running __P((const DB_TXN *));
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static int __txn_end __P((DB_TXN *, int));
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static int __txn_grow_region __P((DB_TXNMGR *));
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static int __txn_init __P((DB_TXNREGION *));
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static int __txn_undo __P((DB_TXN *));
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static int __txn_validate_region __P((DB_TXNMGR *));
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/*
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* This file contains the top level routines of the transaction library.
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* It assumes that a lock manager and log manager that conform to the db_log(3)
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* and db_lock(3) interfaces exist.
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*
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* Initialize a transaction region in shared memory.
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* Return 0 on success, errno on failure.
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*/
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static int
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__txn_init(txn_region)
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DB_TXNREGION *txn_region;
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{
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time_t now;
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(void)time(&now);
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/* maxtxns is already initialized. */
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txn_region->magic = DB_TXNMAGIC;
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txn_region->version = DB_TXNVERSION;
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txn_region->last_txnid = TXN_MINIMUM;
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/* XXX If we ever do more types of locking and logging, this changes. */
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txn_region->logtype = 0;
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txn_region->locktype = 0;
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txn_region->time_ckp = now;
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ZERO_LSN(txn_region->last_ckp);
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ZERO_LSN(txn_region->pending_ckp);
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SH_TAILQ_INIT(&txn_region->active_txn);
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__db_shalloc_init((void *)&txn_region[1],
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TXN_REGION_SIZE(txn_region->maxtxns) - sizeof(DB_TXNREGION));
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return (0);
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}
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int
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txn_open(path, flags, mode, dbenv, mgrpp)
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const char *path;
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u_int32_t flags;
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int mode;
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DB_ENV *dbenv;
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DB_TXNMGR **mgrpp;
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{
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DB_TXNMGR *tmgrp;
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u_int32_t maxtxns;
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int ret;
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/* Validate arguments. */
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if (dbenv == NULL)
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return (EINVAL);
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#ifdef HAVE_SPINLOCKS
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#define OKFLAGS (DB_CREATE | DB_THREAD | DB_TXN_NOSYNC)
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#else
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#define OKFLAGS (DB_CREATE | DB_TXN_NOSYNC)
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#endif
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if ((ret = __db_fchk(dbenv, "txn_open", flags, OKFLAGS)) != 0)
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return (ret);
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maxtxns = dbenv->tx_max != 0 ? dbenv->tx_max : 20;
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/* Now, create the transaction manager structure and set its fields. */
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if ((tmgrp = (DB_TXNMGR *)__db_calloc(1, sizeof(DB_TXNMGR))) == NULL) {
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__db_err(dbenv, "txn_open: %s", strerror(ENOMEM));
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return (ENOMEM);
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}
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/* Initialize the transaction manager structure. */
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tmgrp->mutexp = NULL;
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tmgrp->dbenv = dbenv;
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tmgrp->recover =
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dbenv->tx_recover == NULL ? __db_dispatch : dbenv->tx_recover;
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tmgrp->flags = LF_ISSET(DB_TXN_NOSYNC | DB_THREAD);
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TAILQ_INIT(&tmgrp->txn_chain);
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/* Join/create the txn region. */
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tmgrp->reginfo.dbenv = dbenv;
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tmgrp->reginfo.appname = DB_APP_NONE;
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if (path == NULL)
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tmgrp->reginfo.path = NULL;
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else
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if ((tmgrp->reginfo.path = (char *)__db_strdup(path)) == NULL)
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goto err;
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tmgrp->reginfo.file = DEFAULT_TXN_FILE;
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tmgrp->reginfo.mode = mode;
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tmgrp->reginfo.size = TXN_REGION_SIZE(maxtxns);
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tmgrp->reginfo.dbflags = flags;
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tmgrp->reginfo.addr = NULL;
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tmgrp->reginfo.fd = -1;
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tmgrp->reginfo.flags = dbenv->tx_max == 0 ? REGION_SIZEDEF : 0;
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if ((ret = __db_rattach(&tmgrp->reginfo)) != 0)
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goto err;
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/* Fill in region-related fields. */
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tmgrp->region = tmgrp->reginfo.addr;
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tmgrp->mem = &tmgrp->region[1];
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if (F_ISSET(&tmgrp->reginfo, REGION_CREATED)) {
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tmgrp->region->maxtxns = maxtxns;
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if ((ret = __txn_init(tmgrp->region)) != 0)
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goto err;
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} else if (tmgrp->region->magic != DB_TXNMAGIC) {
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/* Check if valid region. */
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__db_err(dbenv, "txn_open: Bad magic number");
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ret = EINVAL;
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goto err;
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}
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if (LF_ISSET(DB_THREAD)) {
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if ((ret = __db_shalloc(tmgrp->mem, sizeof(db_mutex_t),
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MUTEX_ALIGNMENT, &tmgrp->mutexp)) == 0)
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/*
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* Since we only get here if threading is turned on, we
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* know that we have spinlocks, so the offset is going
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* to be ignored. We put 0 here as a valid placeholder.
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*/
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__db_mutex_init(tmgrp->mutexp, 0);
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if (ret != 0)
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goto err;
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}
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UNLOCK_TXNREGION(tmgrp);
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*mgrpp = tmgrp;
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return (0);
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err: if (tmgrp->reginfo.addr != NULL) {
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if (tmgrp->mutexp != NULL)
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__db_shalloc_free(tmgrp->mem, tmgrp->mutexp);
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UNLOCK_TXNREGION(tmgrp);
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(void)__db_rdetach(&tmgrp->reginfo);
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if (F_ISSET(&tmgrp->reginfo, REGION_CREATED))
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(void)txn_unlink(path, 1, dbenv);
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}
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if (tmgrp->reginfo.path != NULL)
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FREES(tmgrp->reginfo.path);
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FREE(tmgrp, sizeof(*tmgrp));
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return (ret);
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}
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/*
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* Internally, we use TXN_DETAIL structures, but we allocate and return
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* DB_TXN structures that provide access to the transaction ID and the
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* offset in the transaction region of the TXN_DETAIL structure.
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*/
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int
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txn_begin(tmgrp, parent, txnpp)
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DB_TXNMGR *tmgrp;
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DB_TXN *parent;
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DB_TXN **txnpp;
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{
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DB_LSN begin_lsn;
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DB_TXN *retp;
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TXN_DETAIL *txnp;
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size_t off;
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u_int32_t id;
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int ret;
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txnp = NULL;
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*txnpp = NULL;
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if ((retp = (DB_TXN *)__db_malloc(sizeof(DB_TXN))) == NULL) {
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__db_err(tmgrp->dbenv, "txn_begin : %s", strerror(ENOMEM));
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return (ENOMEM);
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}
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/*
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* We do not have to write begin records (and if we do not, then we
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* need never write records for read-only transactions). However,
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* we do need to find the current LSN so that we can store it in the
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* transaction structure, so we can know where to take checkpoints.
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*/
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if (tmgrp->dbenv->lg_info != NULL && (ret =
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log_put(tmgrp->dbenv->lg_info, &begin_lsn, NULL, DB_CURLSN)) != 0)
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goto err2;
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LOCK_TXNREGION(tmgrp);
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/* Make sure that last_txnid is not going to wrap around. */
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if (tmgrp->region->last_txnid == TXN_INVALID) {
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__db_err(tmgrp->dbenv, "txn_begin: %s %s",
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"Transaction ID wrapping.",
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"Snapshot your database and start a new log.");
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ret = EINVAL;
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goto err1;
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}
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if ((ret = __txn_validate_region(tmgrp)) != 0)
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goto err1;
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/* Allocate a new transaction detail structure. */
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if ((ret = __db_shalloc(tmgrp->mem, sizeof(TXN_DETAIL), 0, &txnp)) != 0
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&& ret == ENOMEM && (ret = __txn_grow_region(tmgrp)) == 0)
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ret = __db_shalloc(tmgrp->mem, sizeof(TXN_DETAIL), 0, &txnp);
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if (ret != 0)
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goto err1;
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/* Place transaction on active transaction list. */
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SH_TAILQ_INSERT_HEAD(&tmgrp->region->active_txn,
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txnp, links, __txn_detail);
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id = ++tmgrp->region->last_txnid;
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tmgrp->region->nbegins++;
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txnp->txnid = id;
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txnp->begin_lsn = begin_lsn;
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ZERO_LSN(txnp->last_lsn);
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txnp->last_lock = 0;
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txnp->status = TXN_RUNNING;
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off = (u_int8_t *)txnp - (u_int8_t *)tmgrp->region;
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UNLOCK_TXNREGION(tmgrp);
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ZERO_LSN(retp->last_lsn);
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retp->txnid = id;
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retp->parent = parent;
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retp->mgrp = tmgrp;
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retp->off = off;
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LOCK_TXNTHREAD(tmgrp);
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TAILQ_INSERT_TAIL(&tmgrp->txn_chain, retp, links);
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UNLOCK_TXNTHREAD(tmgrp);
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*txnpp = retp;
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return (0);
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err1: UNLOCK_TXNREGION(tmgrp);
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err2: __db_free(retp);
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return (ret);
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}
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/*
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* txn_commit --
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* Commit a transaction.
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*/
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int
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txn_commit(txnp)
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DB_TXN *txnp;
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{
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DB_LOG *logp;
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int ret;
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if ((ret = __txn_check_running(txnp)) != 0)
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return (ret);
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/*
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* If there are any log records, write a log record and sync
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* the log, else do no log writes.
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*/
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if ((logp = txnp->mgrp->dbenv->lg_info) != NULL &&
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!IS_ZERO_LSN(txnp->last_lsn) &&
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(ret = __txn_regop_log(logp, txnp, &txnp->last_lsn,
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F_ISSET(txnp->mgrp, DB_TXN_NOSYNC) ? 0 : DB_FLUSH,
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TXN_COMMIT)) != 0)
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return (ret);
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return (__txn_end(txnp, 1));
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}
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/*
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* txn_abort --
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* Abort a transcation.
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*/
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int
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txn_abort(txnp)
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DB_TXN *txnp;
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{
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int ret;
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if ((ret = __txn_check_running(txnp)) != 0)
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return (ret);
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if ((ret = __txn_undo(txnp)) != 0) {
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__db_err(txnp->mgrp->dbenv,
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"txn_abort: Log undo failed %s", strerror(ret));
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return (ret);
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}
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return (__txn_end(txnp, 0));
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}
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/*
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* Flush the log so a future commit is guaranteed to succeed.
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*/
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int
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txn_prepare(txnp)
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DB_TXN *txnp;
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{
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TXN_DETAIL *tp;
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int ret;
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if ((ret = __txn_check_running(txnp)) != 0)
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return (ret);
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if (txnp->mgrp->dbenv->lg_info != NULL) {
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if ((ret = log_flush(txnp->mgrp->dbenv->lg_info,
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&txnp->last_lsn)) != 0)
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__db_err(txnp->mgrp->dbenv,
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"txn_prepare: log_flush failed %s\n",
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strerror(ret));
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return (ret);
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}
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LOCK_TXNTHREAD(txnp->mgrp);
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tp = (TXN_DETAIL *)((u_int8_t *)txnp->mgrp->region + txnp->off);
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tp->status = TXN_PREPARED;
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UNLOCK_TXNTHREAD(txnp->mgrp);
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return (ret);
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}
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|
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/*
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* Return the transaction ID associated with a particular transaction
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*/
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u_int32_t
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txn_id(txnp)
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DB_TXN *txnp;
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{
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return (txnp->txnid);
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}
|
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|
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/*
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* txn_close --
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* Close the transaction region, does not imply a checkpoint.
|
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*/
|
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int
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txn_close(tmgrp)
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DB_TXNMGR *tmgrp;
|
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{
|
|
DB_TXN *txnp;
|
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int ret, t_ret;
|
|
|
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ret = 0;
|
|
|
|
/*
|
|
* This function had better only be called once per process
|
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* (i.e., not per thread), so there should be no synchronization
|
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* required.
|
|
*/
|
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while ((txnp =
|
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TAILQ_FIRST(&tmgrp->txn_chain)) != TAILQ_END(&tmgrp->txn_chain))
|
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if ((t_ret = txn_abort(txnp)) != 0) {
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__txn_end(txnp, 0);
|
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if (ret == 0)
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ret = t_ret;
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}
|
|
|
|
if (tmgrp->dbenv->lg_info &&
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(t_ret = log_flush(tmgrp->dbenv->lg_info, NULL)) != 0 && ret == 0)
|
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ret = t_ret;
|
|
|
|
if (tmgrp->mutexp != NULL) {
|
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LOCK_TXNREGION(tmgrp);
|
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__db_shalloc_free(tmgrp->mem, tmgrp->mutexp);
|
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UNLOCK_TXNREGION(tmgrp);
|
|
}
|
|
|
|
if ((t_ret = __db_rdetach(&tmgrp->reginfo)) != 0 && ret == 0)
|
|
ret = t_ret;
|
|
|
|
if (tmgrp->reginfo.path != NULL)
|
|
FREES(tmgrp->reginfo.path);
|
|
FREE(tmgrp, sizeof(*tmgrp));
|
|
|
|
return (ret);
|
|
}
|
|
|
|
/*
|
|
* txn_unlink --
|
|
* Remove the transaction region.
|
|
*/
|
|
int
|
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txn_unlink(path, force, dbenv)
|
|
const char *path;
|
|
int force;
|
|
DB_ENV *dbenv;
|
|
{
|
|
REGINFO reginfo;
|
|
int ret;
|
|
|
|
memset(®info, 0, sizeof(reginfo));
|
|
reginfo.dbenv = dbenv;
|
|
reginfo.appname = DB_APP_NONE;
|
|
if (path != NULL && (reginfo.path = (char *)__db_strdup(path)) == NULL)
|
|
return (ENOMEM);
|
|
reginfo.file = DEFAULT_TXN_FILE;
|
|
ret = __db_runlink(®info, force);
|
|
if (reginfo.path != NULL)
|
|
FREES(reginfo.path);
|
|
return (ret);
|
|
}
|
|
|
|
/* Internal routines. */
|
|
|
|
/*
|
|
* Return 0 if the txnp is reasonable, otherwise returns EINVAL.
|
|
*/
|
|
static int
|
|
__txn_check_running(txnp)
|
|
const DB_TXN *txnp;
|
|
{
|
|
TXN_DETAIL *tp;
|
|
|
|
tp = NULL;
|
|
if (txnp != NULL && txnp->mgrp != NULL && txnp->mgrp->region != NULL) {
|
|
tp = (TXN_DETAIL *)((u_int8_t *)txnp->mgrp->region + txnp->off);
|
|
if (tp->status != TXN_RUNNING)
|
|
tp = NULL;
|
|
}
|
|
|
|
return (tp == NULL ? EINVAL : 0);
|
|
}
|
|
|
|
static int
|
|
__txn_end(txnp, is_commit)
|
|
DB_TXN *txnp;
|
|
int is_commit;
|
|
{
|
|
DB_TXNMGR *mgr;
|
|
TXN_DETAIL *tp;
|
|
DB_LOCKREQ request;
|
|
int ret;
|
|
u_int32_t locker;
|
|
|
|
mgr = txnp->mgrp;
|
|
|
|
LOCK_TXNTHREAD(mgr);
|
|
TAILQ_REMOVE(&mgr->txn_chain, txnp, links);
|
|
UNLOCK_TXNTHREAD(mgr);
|
|
|
|
/* Release the locks. */
|
|
locker = txnp->txnid;
|
|
request.op = DB_LOCK_PUT_ALL;
|
|
|
|
if (mgr->dbenv->lk_info) {
|
|
ret = lock_vec(mgr->dbenv->lk_info, locker, 0,
|
|
&request, 1, NULL);
|
|
if (ret != 0 && (ret != DB_LOCK_DEADLOCK || is_commit)) {
|
|
__db_err(mgr->dbenv, "%s: release locks failed %s",
|
|
is_commit ? "txn_commit" : "txn_abort",
|
|
strerror(ret));
|
|
return (ret);
|
|
}
|
|
}
|
|
|
|
/* End the transaction. */
|
|
LOCK_TXNREGION(mgr);
|
|
tp = (TXN_DETAIL *)((u_int8_t *)mgr->region + txnp->off);
|
|
SH_TAILQ_REMOVE(&mgr->region->active_txn, tp, links, __txn_detail);
|
|
__db_shalloc_free(mgr->mem, tp);
|
|
if (is_commit)
|
|
mgr->region->ncommits++;
|
|
else
|
|
mgr->region->naborts++;
|
|
UNLOCK_TXNREGION(mgr);
|
|
|
|
FREE(txnp, sizeof(*txnp));
|
|
|
|
return (0);
|
|
}
|
|
|
|
|
|
/*
|
|
* __txn_undo --
|
|
* Undo the transaction with id txnid. Returns 0 on success and
|
|
* errno on failure.
|
|
*/
|
|
static int
|
|
__txn_undo(txnp)
|
|
DB_TXN *txnp;
|
|
{
|
|
DBT rdbt;
|
|
DB_LOG *logp;
|
|
DB_LSN key_lsn;
|
|
DB_TXNMGR *mgr;
|
|
int ret;
|
|
|
|
mgr = txnp->mgrp;
|
|
logp = mgr->dbenv->lg_info;
|
|
if (logp == NULL)
|
|
return (0);
|
|
|
|
/*
|
|
* This is the simplest way to code this, but if the mallocs during
|
|
* recovery turn out to be a performance issue, we can do the
|
|
* allocation here and use DB_DBT_USERMEM.
|
|
*/
|
|
memset(&rdbt, 0, sizeof(rdbt));
|
|
if (F_ISSET(logp, DB_AM_THREAD))
|
|
F_SET(&rdbt, DB_DBT_MALLOC);
|
|
|
|
key_lsn = txnp->last_lsn; /* structure assignment */
|
|
for (ret = 0; ret == 0 && !IS_ZERO_LSN(key_lsn);) {
|
|
/*
|
|
* The dispatch routine returns the lsn of the record
|
|
* before the current one in the key_lsn argument.
|
|
*/
|
|
if ((ret = log_get(logp, &key_lsn, &rdbt, DB_SET)) == 0) {
|
|
ret =
|
|
mgr->recover(logp, &rdbt, &key_lsn, TXN_UNDO, NULL);
|
|
if (F_ISSET(logp, DB_AM_THREAD) && rdbt.data != NULL) {
|
|
__db_free(rdbt.data);
|
|
rdbt.data = NULL;
|
|
}
|
|
}
|
|
if (ret != 0)
|
|
return (ret);
|
|
}
|
|
|
|
return (ret);
|
|
}
|
|
|
|
/*
|
|
* Transaction checkpoint.
|
|
* If either kbytes or minutes is non-zero, then we only take the checkpoint
|
|
* more than "minutes" minutes have passed since the last checkpoint or if
|
|
* more than "kbytes" of log data have been written since the last checkpoint.
|
|
* When taking a checkpoint, find the oldest active transaction and figure out
|
|
* its first LSN. This is the lowest LSN we can checkpoint, since any record
|
|
* written after since that point may be involved in a transaction and may
|
|
* therefore need to be undone in the case of an abort.
|
|
*/
|
|
int
|
|
txn_checkpoint(mgr, kbytes, minutes)
|
|
const DB_TXNMGR *mgr;
|
|
u_int32_t kbytes, minutes;
|
|
{
|
|
TXN_DETAIL *txnp;
|
|
DB_LSN ckp_lsn, last_ckp;
|
|
DB_LOG *dblp;
|
|
u_int32_t kbytes_written;
|
|
time_t last_ckp_time, now;
|
|
int ret;
|
|
|
|
/*
|
|
* Check if we need to run recovery.
|
|
*/
|
|
ZERO_LSN(ckp_lsn);
|
|
if (minutes != 0) {
|
|
(void)time(&now);
|
|
|
|
LOCK_TXNREGION(mgr);
|
|
last_ckp_time = mgr->region->time_ckp;
|
|
UNLOCK_TXNREGION(mgr);
|
|
|
|
if (now - last_ckp_time >= (time_t)(minutes * 60))
|
|
goto do_ckp;
|
|
}
|
|
|
|
if (kbytes != 0) {
|
|
dblp = mgr->dbenv->lg_info;
|
|
LOCK_LOGREGION(dblp);
|
|
kbytes_written =
|
|
dblp->lp->stat.st_wc_mbytes * 1024 +
|
|
dblp->lp->stat.st_wc_bytes / 1024;
|
|
ckp_lsn = dblp->lp->lsn;
|
|
UNLOCK_LOGREGION(dblp);
|
|
if (kbytes_written >= (u_int32_t)kbytes)
|
|
goto do_ckp;
|
|
}
|
|
|
|
/*
|
|
* If we checked time and data and didn't go to checkpoint,
|
|
* we're done.
|
|
*/
|
|
if (minutes != 0 || kbytes != 0)
|
|
return (0);
|
|
|
|
do_ckp:
|
|
if (IS_ZERO_LSN(ckp_lsn)) {
|
|
dblp = mgr->dbenv->lg_info;
|
|
LOCK_LOGREGION(dblp);
|
|
ckp_lsn = dblp->lp->lsn;
|
|
UNLOCK_LOGREGION(dblp);
|
|
}
|
|
|
|
/*
|
|
* We have to find an LSN such that all transactions begun
|
|
* before that LSN are complete.
|
|
*/
|
|
LOCK_TXNREGION(mgr);
|
|
|
|
if (!IS_ZERO_LSN(mgr->region->pending_ckp))
|
|
ckp_lsn = mgr->region->pending_ckp;
|
|
else
|
|
for (txnp =
|
|
SH_TAILQ_FIRST(&mgr->region->active_txn, __txn_detail);
|
|
txnp != NULL;
|
|
txnp = SH_TAILQ_NEXT(txnp, links, __txn_detail)) {
|
|
|
|
/*
|
|
* Look through the active transactions for the
|
|
* lowest begin lsn.
|
|
*/
|
|
if (!IS_ZERO_LSN(txnp->begin_lsn) &&
|
|
log_compare(&txnp->begin_lsn, &ckp_lsn) < 0)
|
|
ckp_lsn = txnp->begin_lsn;
|
|
}
|
|
|
|
mgr->region->pending_ckp = ckp_lsn;
|
|
UNLOCK_TXNREGION(mgr);
|
|
|
|
if (mgr->dbenv->mp_info != NULL &&
|
|
(ret = memp_sync(mgr->dbenv->mp_info, &ckp_lsn)) != 0) {
|
|
/*
|
|
* ret == DB_INCOMPLETE means that there are still buffers to
|
|
* flush, the checkpoint is not complete. Wait and try again.
|
|
*/
|
|
if (ret > 0)
|
|
__db_err(mgr->dbenv,
|
|
"txn_checkpoint: system failure in memp_sync %s\n",
|
|
strerror(ret));
|
|
return (ret);
|
|
}
|
|
if (mgr->dbenv->lg_info != NULL) {
|
|
LOCK_TXNREGION(mgr);
|
|
last_ckp = mgr->region->last_ckp;
|
|
ZERO_LSN(mgr->region->pending_ckp);
|
|
UNLOCK_TXNREGION(mgr);
|
|
|
|
if ((ret = __txn_ckp_log(mgr->dbenv->lg_info,
|
|
NULL, &ckp_lsn, DB_CHECKPOINT, &ckp_lsn, &last_ckp)) != 0) {
|
|
__db_err(mgr->dbenv,
|
|
"txn_checkpoint: log failed at LSN [%ld %ld] %s\n",
|
|
(long)ckp_lsn.file, (long)ckp_lsn.offset,
|
|
strerror(ret));
|
|
return (ret);
|
|
}
|
|
|
|
LOCK_TXNREGION(mgr);
|
|
mgr->region->last_ckp = ckp_lsn;
|
|
(void)time(&mgr->region->time_ckp);
|
|
UNLOCK_TXNREGION(mgr);
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* __txn_validate_region --
|
|
* Called at every interface to verify if the region has changed size,
|
|
* and if so, to remap the region in and reset the process' pointers.
|
|
*/
|
|
static int
|
|
__txn_validate_region(tp)
|
|
DB_TXNMGR *tp;
|
|
{
|
|
int ret;
|
|
|
|
if (tp->reginfo.size == tp->region->hdr.size)
|
|
return (0);
|
|
|
|
/* Detach/reattach the region. */
|
|
if ((ret = __db_rreattach(&tp->reginfo, tp->region->hdr.size)) != 0)
|
|
return (ret);
|
|
|
|
/* Reset region information. */
|
|
tp->region = tp->reginfo.addr;
|
|
tp->mem = &tp->region[1];
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
__txn_grow_region(tp)
|
|
DB_TXNMGR *tp;
|
|
{
|
|
size_t incr, oldsize;
|
|
u_int32_t mutex_offset, oldmax;
|
|
u_int8_t *curaddr;
|
|
int ret;
|
|
|
|
oldmax = tp->region->maxtxns;
|
|
incr = oldmax * sizeof(DB_TXN);
|
|
mutex_offset = tp->mutexp != NULL ?
|
|
(u_int8_t *)tp->mutexp - (u_int8_t *)tp->region : 0;
|
|
|
|
oldsize = tp->reginfo.size;
|
|
if ((ret = __db_rgrow(&tp->reginfo, oldsize + incr)) != 0)
|
|
return (ret);
|
|
tp->region = tp->reginfo.addr;
|
|
|
|
/* Throw the new space on the free list. */
|
|
curaddr = (u_int8_t *)tp->region + oldsize;
|
|
tp->mem = &tp->region[1];
|
|
tp->mutexp = mutex_offset != 0 ?
|
|
(db_mutex_t *)((u_int8_t *)tp->region + mutex_offset) : NULL;
|
|
|
|
*((size_t *)curaddr) = incr - sizeof(size_t);
|
|
curaddr += sizeof(size_t);
|
|
__db_shalloc_free(tp->mem, curaddr);
|
|
|
|
tp->region->maxtxns = 2 * oldmax;
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
txn_stat(mgr, statp, db_malloc)
|
|
DB_TXNMGR *mgr;
|
|
DB_TXN_STAT **statp;
|
|
void *(*db_malloc) __P((size_t));
|
|
{
|
|
DB_TXN_STAT *stats;
|
|
TXN_DETAIL *txnp;
|
|
size_t nbytes;
|
|
u_int32_t nactive, ndx;
|
|
|
|
LOCK_TXNREGION(mgr);
|
|
nactive = mgr->region->nbegins -
|
|
mgr->region->naborts - mgr->region->ncommits;
|
|
UNLOCK_TXNREGION(mgr);
|
|
|
|
/*
|
|
* Allocate a bunch of extra active structures to handle any
|
|
* that have been created since we unlocked the region.
|
|
*/
|
|
nbytes = sizeof(DB_TXN_STAT) + sizeof(DB_TXN_ACTIVE) * (nactive + 200);
|
|
if (db_malloc == NULL)
|
|
stats = (DB_TXN_STAT *)__db_malloc(nbytes);
|
|
else
|
|
stats = (DB_TXN_STAT *)db_malloc(nbytes);
|
|
|
|
if (stats == NULL)
|
|
return (ENOMEM);
|
|
|
|
LOCK_TXNREGION(mgr);
|
|
stats->st_last_txnid = mgr->region->last_txnid;
|
|
stats->st_last_ckp = mgr->region->last_ckp;
|
|
stats->st_maxtxns = mgr->region->maxtxns;
|
|
stats->st_naborts = mgr->region->naborts;
|
|
stats->st_nbegins = mgr->region->nbegins;
|
|
stats->st_ncommits = mgr->region->ncommits;
|
|
stats->st_pending_ckp = mgr->region->pending_ckp;
|
|
stats->st_time_ckp = mgr->region->time_ckp;
|
|
stats->st_nactive = stats->st_nbegins -
|
|
stats->st_naborts - stats->st_ncommits;
|
|
if (stats->st_nactive > nactive + 200)
|
|
stats->st_nactive = nactive + 200;
|
|
stats->st_txnarray = (DB_TXN_ACTIVE *)&stats[1];
|
|
|
|
ndx = 0;
|
|
for (txnp = SH_TAILQ_FIRST(&mgr->region->active_txn, __txn_detail);
|
|
txnp != NULL;
|
|
txnp = SH_TAILQ_NEXT(txnp, links, __txn_detail)) {
|
|
stats->st_txnarray[ndx].txnid = txnp->txnid;
|
|
stats->st_txnarray[ndx].lsn = txnp->begin_lsn;
|
|
ndx++;
|
|
|
|
if (ndx >= stats->st_nactive)
|
|
break;
|
|
}
|
|
|
|
stats->st_region_wait = mgr->region->hdr.lock.mutex_set_wait;
|
|
stats->st_region_nowait = mgr->region->hdr.lock.mutex_set_nowait;
|
|
stats->st_refcnt = mgr->region->hdr.refcnt;
|
|
stats->st_regsize = mgr->region->hdr.size;
|
|
|
|
UNLOCK_TXNREGION(mgr);
|
|
*statp = stats;
|
|
return (0);
|
|
}
|