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Diffstat (limited to 'db2/include/mp.h')
| -rw-r--r-- | db2/include/mp.h | 299 |
1 files changed, 0 insertions, 299 deletions
diff --git a/db2/include/mp.h b/db2/include/mp.h deleted file mode 100644 index 904bccf..0000000 --- a/db2/include/mp.h +++ /dev/null @@ -1,299 +0,0 @@ -/*- - * See the file LICENSE for redistribution information. - * - * Copyright (c) 1996, 1997, 1998 - * Sleepycat Software. All rights reserved. - * - * @(#)mp.h 10.37 (Sleepycat) 1/1/99 - */ - -struct __bh; typedef struct __bh BH; -struct __db_mpreg; typedef struct __db_mpreg DB_MPREG; -struct __mpool; typedef struct __mpool MPOOL; -struct __mpoolfile; typedef struct __mpoolfile MPOOLFILE; - - /* Default mpool name. */ -#define DB_DEFAULT_MPOOL_FILE "__db_mpool.share" - -/* - * We default to 256K (32 8K pages) if the user doesn't specify, and - * require a minimum of 20K. - */ -#ifndef DB_CACHESIZE_DEF -#define DB_CACHESIZE_DEF (256 * 1024) -#endif -#define DB_CACHESIZE_MIN ( 20 * 1024) - -#define INVALID 0 /* Invalid shared memory offset. */ - -/* - * There are three ways we do locking in the mpool code: - * - * Locking a handle mutex to provide concurrency for DB_THREAD operations. - * Locking the region mutex to provide mutual exclusion while reading and - * writing structures in the shared region. - * Locking buffer header mutexes during I/O. - * - * The first will not be further described here. We use the shared mpool - * region lock to provide mutual exclusion while reading/modifying all of - * the data structures, including the buffer headers. We use a per-buffer - * header lock to wait on buffer I/O. The order of locking is as follows: - * - * Searching for a buffer: - * Acquire the region lock. - * Find the buffer header. - * Increment the reference count (guarantee the buffer stays). - * While the BH_LOCKED flag is set (I/O is going on) { - * Release the region lock. - * Explicitly yield the processor if it's not the first pass - * through this loop, otherwise, we can simply spin because - * we'll be simply switching between the two locks. - * Request the buffer lock. - * The I/O will complete... - * Acquire the buffer lock. - * Release the buffer lock. - * Acquire the region lock. - * } - * Return the buffer. - * - * Reading/writing a buffer: - * Acquire the region lock. - * Find/create the buffer header. - * If reading, increment the reference count (guarantee the buffer stays). - * Set the BH_LOCKED flag. - * Acquire the buffer lock (guaranteed not to block). - * Release the region lock. - * Do the I/O and/or initialize the buffer contents. - * Release the buffer lock. - * At this point, the buffer lock is available, but the logical - * operation (flagged by BH_LOCKED) is not yet completed. For - * this reason, among others, threads checking the BH_LOCKED flag - * must loop around their test. - * Acquire the region lock. - * Clear the BH_LOCKED flag. - * Release the region lock. - * Return/discard the buffer. - * - * Pointers to DB_MPOOL, MPOOL, DB_MPOOLFILE and MPOOLFILE structures are not - * reacquired when a region lock is reacquired because they couldn't have been - * closed/discarded and because they never move in memory. - */ -#define LOCKINIT(dbmp, mutexp) \ - if (F_ISSET(dbmp, MP_LOCKHANDLE | MP_LOCKREGION)) \ - (void)__db_mutex_init(mutexp, \ - MUTEX_LOCK_OFFSET((dbmp)->reginfo.addr, mutexp)) - -#define LOCKHANDLE(dbmp, mutexp) \ - if (F_ISSET(dbmp, MP_LOCKHANDLE)) \ - (void)__db_mutex_lock(mutexp, (dbmp)->reginfo.fd) -#define UNLOCKHANDLE(dbmp, mutexp) \ - if (F_ISSET(dbmp, MP_LOCKHANDLE)) \ - (void)__db_mutex_unlock(mutexp, (dbmp)->reginfo.fd) - -#define LOCKREGION(dbmp) \ - if (F_ISSET(dbmp, MP_LOCKREGION)) \ - (void)__db_mutex_lock(&((RLAYOUT *)(dbmp)->mp)->lock, \ - (dbmp)->reginfo.fd) -#define UNLOCKREGION(dbmp) \ - if (F_ISSET(dbmp, MP_LOCKREGION)) \ - (void)__db_mutex_unlock(&((RLAYOUT *)(dbmp)->mp)->lock, \ - (dbmp)->reginfo.fd) - -#define LOCKBUFFER(dbmp, bhp) \ - if (F_ISSET(dbmp, MP_LOCKREGION)) \ - (void)__db_mutex_lock(&(bhp)->mutex, (dbmp)->reginfo.fd) -#define UNLOCKBUFFER(dbmp, bhp) \ - if (F_ISSET(dbmp, MP_LOCKREGION)) \ - (void)__db_mutex_unlock(&(bhp)->mutex, (dbmp)->reginfo.fd) - -/* Check for region catastrophic shutdown. */ -#define MP_PANIC_CHECK(dbmp) { \ - if ((dbmp)->mp->rlayout.panic) \ - return (DB_RUNRECOVERY); \ -} - -/* - * DB_MPOOL -- - * Per-process memory pool structure. - */ -struct __db_mpool { -/* These fields need to be protected for multi-threaded support. */ - db_mutex_t *mutexp; /* Structure lock. */ - - /* List of pgin/pgout routines. */ - LIST_HEAD(__db_mpregh, __db_mpreg) dbregq; - - /* List of DB_MPOOLFILE's. */ - TAILQ_HEAD(__db_mpoolfileh, __db_mpoolfile) dbmfq; - -/* These fields are not protected. */ - DB_ENV *dbenv; /* Reference to error information. */ - REGINFO reginfo; /* Region information. */ - - MPOOL *mp; /* Address of the shared MPOOL. */ - - void *addr; /* Address of shalloc() region. */ - - DB_HASHTAB *htab; /* Hash table of bucket headers. */ - -#define MP_LOCKHANDLE 0x01 /* Threaded, lock handles and region. */ -#define MP_LOCKREGION 0x02 /* Concurrent access, lock region. */ - u_int32_t flags; -}; - -/* - * DB_MPREG -- - * DB_MPOOL registry of pgin/pgout functions. - */ -struct __db_mpreg { - LIST_ENTRY(__db_mpreg) q; /* Linked list. */ - - int ftype; /* File type. */ - /* Pgin, pgout routines. */ - int (DB_CALLBACK *pgin) __P((db_pgno_t, void *, DBT *)); - int (DB_CALLBACK *pgout) __P((db_pgno_t, void *, DBT *)); -}; - -/* - * DB_MPOOLFILE -- - * Per-process DB_MPOOLFILE information. - */ -struct __db_mpoolfile { -/* These fields need to be protected for multi-threaded support. */ - db_mutex_t *mutexp; /* Structure lock. */ - - int fd; /* Underlying file descriptor. */ - - u_int32_t ref; /* Reference count. */ - - /* - * !!! - * This field is a special case -- it's protected by the region lock - * NOT the thread lock. The reason for this is that we always have - * the region lock immediately before or after we modify the field, - * and we don't want to use the structure lock to protect it because - * then I/O (which is done with the structure lock held because of - * the race between the seek and write of the file descriptor) will - * block any other put/get calls using this DB_MPOOLFILE structure. - */ - u_int32_t pinref; /* Pinned block reference count. */ - -/* These fields are not protected. */ - TAILQ_ENTRY(__db_mpoolfile) q; /* Linked list of DB_MPOOLFILE's. */ - - DB_MPOOL *dbmp; /* Overlying DB_MPOOL. */ - MPOOLFILE *mfp; /* Underlying MPOOLFILE. */ - - void *addr; /* Address of mmap'd region. */ - size_t len; /* Length of mmap'd region. */ - -/* These fields need to be protected for multi-threaded support. */ -#define MP_READONLY 0x01 /* File is readonly. */ -#define MP_UPGRADE 0x02 /* File descriptor is readwrite. */ -#define MP_UPGRADE_FAIL 0x04 /* Upgrade wasn't possible. */ - u_int32_t flags; -}; - -/* - * MPOOL -- - * Shared memory pool region. One of these is allocated in shared - * memory, and describes the pool. - */ -struct __mpool { - RLAYOUT rlayout; /* General region information. */ - - SH_TAILQ_HEAD(__bhq) bhq; /* LRU list of buckets. */ - SH_TAILQ_HEAD(__bhfq) bhfq; /* Free buckets. */ - SH_TAILQ_HEAD(__mpfq) mpfq; /* List of MPOOLFILEs. */ - - /* - * We make the assumption that the early pages of the file are far - * more likely to be retrieved than the later pages, which means - * that the top bits are more interesting for hashing since they're - * less likely to collide. On the other hand, since 512 4K pages - * represents a 2MB file, only the bottom 9 bits of the page number - * are likely to be set. We XOR in the offset in the MPOOL of the - * MPOOLFILE that backs this particular page, since that should also - * be unique for the page. - */ -#define BUCKET(mp, mf_offset, pgno) \ - (((pgno) ^ ((mf_offset) << 9)) % (mp)->htab_buckets) - - size_t htab; /* Hash table offset. */ - size_t htab_buckets; /* Number of hash table entries. */ - - DB_LSN lsn; /* Maximum checkpoint LSN. */ - u_int32_t lsn_cnt; /* Checkpoint buffers left to write. */ - - DB_MPOOL_STAT stat; /* Global mpool statistics. */ - -#define MP_LSN_RETRY 0x01 /* Retry all BH_WRITE buffers. */ - u_int32_t flags; -}; - -/* - * MPOOLFILE -- - * Shared DB_MPOOLFILE information. - */ -struct __mpoolfile { - SH_TAILQ_ENTRY q; /* List of MPOOLFILEs */ - - u_int32_t ref; /* Reference count. */ - - int ftype; /* File type. */ - - int32_t lsn_off; /* Page's LSN offset. */ - u_int32_t clear_len; /* Bytes to clear on page create. */ - - size_t path_off; /* File name location. */ - size_t fileid_off; /* File identification location. */ - - size_t pgcookie_len; /* Pgin/pgout cookie length. */ - size_t pgcookie_off; /* Pgin/pgout cookie location. */ - - u_int32_t lsn_cnt; /* Checkpoint buffers left to write. */ - - db_pgno_t last_pgno; /* Last page in the file. */ - db_pgno_t orig_last_pgno; /* Original last page in the file. */ - -#define MP_CAN_MMAP 0x01 /* If the file can be mmap'd. */ -#define MP_TEMP 0x02 /* Backing file is a temporary. */ - u_int32_t flags; - - DB_MPOOL_FSTAT stat; /* Per-file mpool statistics. */ -}; - -/* - * BH -- - * Buffer header. - */ -struct __bh { - db_mutex_t mutex; /* Structure lock. */ - - u_int16_t ref; /* Reference count. */ - -#define BH_CALLPGIN 0x001 /* Page needs to be reworked... */ -#define BH_DIRTY 0x002 /* Page was modified. */ -#define BH_DISCARD 0x004 /* Page is useless. */ -#define BH_LOCKED 0x008 /* Page is locked (I/O in progress). */ -#define BH_TRASH 0x010 /* Page is garbage. */ -#define BH_WRITE 0x020 /* Page scheduled for writing. */ - u_int16_t flags; - - SH_TAILQ_ENTRY q; /* LRU queue. */ - SH_TAILQ_ENTRY hq; /* MPOOL hash bucket queue. */ - - db_pgno_t pgno; /* Underlying MPOOLFILE page number. */ - size_t mf_offset; /* Associated MPOOLFILE offset. */ - - /* - * !!! - * This array must be size_t aligned -- the DB access methods put PAGE - * and other structures into it, and expect to be able to access them - * directly. (We guarantee size_t alignment in the db_mpool(3) manual - * page as well.) - */ - u_int8_t buf[1]; /* Variable length data. */ -}; - -#include "mp_ext.h" |