diff options
Diffstat (limited to 'db2/include/txn.h')
| -rw-r--r-- | db2/include/txn.h | 27 |
1 files changed, 18 insertions, 9 deletions
diff --git a/db2/include/txn.h b/db2/include/txn.h index f4e0999b36..8bb3976c1c 100644 --- a/db2/include/txn.h +++ b/db2/include/txn.h @@ -4,7 +4,7 @@ * Copyright (c) 1996, 1997 * Sleepycat Software. All rights reserved. * - * @(#)txn.h 10.6 (Sleepycat) 7/29/97 + * @(#)txn.h 10.10 (Sleepycat) 9/23/97 */ #ifndef _TXN_H_ #define _TXN_H_ @@ -14,8 +14,9 @@ * the region is always created group RW of the group owning the directory. */ #define DEFAULT_TXN_FILE "__db_txn.share" +/* TXN_MINIMUM = (DB_LOCK_MAXID + 1) but this makes compilers complain. */ +#define TXN_MINIMUM 0x80000000 #define TXN_INVALID 0xffffffff /* Maximum number of txn ids. */ -#define TXN_MINIMUM 0x80000000 /* First transaction id */ /* * Transaction type declarations. @@ -36,6 +37,7 @@ typedef struct __txn_detail { #define TXN_ABORTED 2 #define TXN_PREPARED 3 u_int32_t status; /* status of the transaction */ + SH_TAILQ_ENTRY links; /* free/active list */ } TXN_DETAIL; /* @@ -45,7 +47,7 @@ typedef struct __txn_detail { */ struct __db_txnmgr { /* These fields need to be protected for multi-threaded support. */ - db_mutex_t mutex; /* Synchronization. */ + db_mutex_t *mutexp; /* Synchronization. */ /* list of active transactions */ TAILQ_HEAD(_chain, __db_txn) txn_chain; @@ -57,11 +59,14 @@ struct __db_txnmgr { u_int flags; /* DB_TXN_NOSYNC, DB_THREAD */ size_t reg_size; /* how large we think the region is */ DB_TXNREGION *region; /* address of shared memory region */ + void *mem; /* address of the shalloc space */ }; /* * Layout of the shared memory region. - * + * The region consists of a DB_TXNREGION structure followed by a large + * pool of shalloc'd memory which is used to hold TXN_DETAIL structures + * and thread mutexes (which are dynamically allocated). */ struct __db_txnregion { RLAYOUT hdr; /* Shared memory region header. */ @@ -69,7 +74,6 @@ struct __db_txnregion { u_int32_t version; /* version number */ u_int32_t maxtxns; /* maximum number of active txns */ u_int32_t last_txnid; /* last transaction id given out */ - u_int32_t free_txn; /* head of transaction free list */ DB_LSN pending_ckp; /* last checkpoint did not finish */ DB_LSN last_ckp; /* lsn of the last checkpoint */ time_t time_ckp; /* time of last checkpoint */ @@ -78,20 +82,25 @@ struct __db_txnregion { u_int32_t naborts; /* number of aborted transactions */ u_int32_t ncommits; /* number of committed transactions */ u_int32_t nbegins; /* number of begun transactions */ - TXN_DETAIL table[1]; /* array of TXN structures */ + SH_TAILQ_HEAD(_active) active_txn; /* active transaction list */ }; +/* + * Make the region large enough to hold N transaction detail structures + * plus some space to hold thread handles and the beginning of the shalloc + * region. + */ #define TXN_REGION_SIZE(N) \ - (sizeof(DB_TXNREGION) + N * sizeof(DB_TXN)) + (sizeof(DB_TXNREGION) + N * sizeof(TXN_DETAIL) + 1000) /* Macros to lock/unlock the region and threads. */ #define LOCK_TXNTHREAD(tmgrp) \ if (F_ISSET(tmgrp, DB_THREAD)) \ - (void)__db_mutex_lock(&(tmgrp)->mutex, -1, \ + (void)__db_mutex_lock((tmgrp)->mutexp, -1, \ (tmgrp)->dbenv == NULL ? NULL : (tmgrp)->dbenv->db_yield) #define UNLOCK_TXNTHREAD(tmgrp) \ if (F_ISSET(tmgrp, DB_THREAD)) \ - (void)__db_mutex_unlock(&(tmgrp)->mutex, -1) + (void)__db_mutex_unlock((tmgrp)->mutexp, -1) #define LOCK_TXNREGION(tmgrp) \ (void)__db_mutex_lock(&(tmgrp)->region->hdr.lock,(tmgrp)->fd, \ |