Import changeset

1 files changed, 244 insertions, 0 deletions

diff --git a/bdb/include/mp.h b/bdb/include/mp.h
new file mode 100644
index 00000000000..233cb1c2b10
--- /dev/null
+++ b/bdb/include/mp.h
@@ -0,0 +1,244 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997, 1998, 1999, 2000
+ *	Sleepycat Software.  All rights reserved.
+ *
+ * $Id: mp.h,v 11.16 2001/01/10 04:50:53 ubell Exp $
+ */
+
+struct __bh;		typedef struct __bh BH;
+struct __db_mpool;	typedef struct __db_mpool DB_MPOOL;
+struct __db_mpreg;	typedef struct __db_mpreg DB_MPREG;
+struct __mpool;		typedef struct __mpool MPOOL;
+struct __mpoolfile;	typedef struct __mpoolfile MPOOLFILE;
+
+/* We require at least 40K of cache. */
+#define	DB_CACHESIZE_MIN	(20 * 1024)
+
+/*
+ * DB_MPOOL --
+ *	Per-process memory pool structure.
+ */
+struct __db_mpool {
+	/* These fields need to be protected for multi-threaded support. */
+	MUTEX	   *mutexp;		/* Structure thread 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 thread-protected. */
+	DB_ENV     *dbenv;		/* Reference to error information. */
+
+	u_int32_t   nreg;		/* N underlying cache regions. */
+	REGINFO	   *reginfo;		/* Underlying cache regions. */
+};
+
+/*
+ * 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 (*pgin) __P((DB_ENV *, db_pgno_t, void *, DBT *));
+	int (*pgout) __P((DB_ENV *, 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. */
+	MUTEX	  *mutexp;		/* Structure thread lock. */
+
+	DB_FH	   fh;			/* Underlying file handle. */
+
+	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. */
+
+	/*
+	 * !!!
+	 * This field is a special case -- it's protected by the region lock
+	 * since it's manipulated only when new files are added to the list.
+	 */
+	TAILQ_ENTRY(__db_mpoolfile) q;	/* Linked list of DB_MPOOLFILE's. */
+
+	/* These fields are not thread-protected. */
+	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;
+};
+
+/*
+ * NCACHE --
+ *	Select a cache based on the page number.  This assumes accesses are
+ *	uniform across pages, which is probably OK -- what we really want to
+ *	avoid is anything that puts all the pages for any single file in the
+ *	same cache, as we expect that file access will be bursty.
+ */
+#define	NCACHE(mp, pgno)						\
+	((pgno) % ((MPOOL *)mp)->nreg)
+
+/*
+ * NBUCKET --
+ *	 We make the assumption that early pages of the file are more likely
+ *	 to be retrieved than the later pages, which means the top bits will
+ *	 be more interesting for hashing as they're less likely to collide.
+ *	 That said, as 512 8K pages represents a 4MB file, so only reasonably
+ *	 large files will have page numbers with any other than the bottom 9
+ *	 bits set.  We XOR in the MPOOL offset of the MPOOLFILE that backs the
+ *	 page, since that should also be unique for the page.  We don't want
+ *	 to do anything very fancy -- speed is more important to us than using
+ *	 good hashing.
+ */
+#define	NBUCKET(mc, mf_offset, pgno)					\
+	(((pgno) ^ ((mf_offset) << 9)) % (mc)->htab_buckets)
+
+/*
+ * MPOOL --
+ *	Shared memory pool region.
+ */
+struct __mpool {
+	/*
+	 * The memory pool can be broken up into individual pieces/files.
+	 * Not what we would have liked, but on Solaris you can allocate
+	 * only a little more than 2GB of memory in a contiguous chunk,
+	 * and I expect to see more systems with similar issues.
+	 *
+	 * The first of these pieces/files describes the entire pool, all
+	 * subsequent ones only describe a part of the cache.
+	 *
+	 * We single-thread memp_sync and memp_fsync calls.
+	 *
+	 * This mutex is intended *only* to single-thread access to the call,
+	 * it is not used to protect the lsn and lsn_cnt fields, the region
+	 * lock is used to protect them.
+	 */
+	MUTEX	  sync_mutex;		/* Checkpoint lock. */
+	DB_LSN	  lsn;			/* Maximum checkpoint LSN. */
+	u_int32_t lsn_cnt;		/* Checkpoint buffers left to write. */
+
+	SH_TAILQ_HEAD(__mpfq) mpfq;	/* List of MPOOLFILEs. */
+
+	u_int32_t nreg;			/* Number of underlying REGIONS. */
+	roff_t	  regids;		/* Array of underlying REGION Ids. */
+
+#define	MP_LSN_RETRY	0x01		/* Retry all BH_WRITE buffers. */
+	u_int32_t  flags;
+
+	/*
+	 * The following structure fields only describe the cache portion of
+	 * the region.
+	 */
+	SH_TAILQ_HEAD(__bhq) bhq;	/* LRU list of buffer headers. */
+
+	int	    htab_buckets;	/* Number of hash table entries. */
+	roff_t	    htab;		/* Hash table offset. */
+
+	DB_MPOOL_STAT stat;		/* Per-cache mpool statistics. */
+#ifdef MUTEX_SYSTEM_RESOURCES
+	roff_t	    maint_off;		/* Maintenance information offset */
+#endif
+};
+
+/*
+ * MPOOLFILE --
+ *	Shared DB_MPOOLFILE information.
+ */
+struct __mpoolfile {
+	SH_TAILQ_ENTRY  q;		/* List of MPOOLFILEs */
+
+	db_pgno_t mpf_cnt;		/* Ref count: DB_MPOOLFILEs. */
+	db_pgno_t block_cnt;		/* Ref count: blocks in cache. */
+	db_pgno_t lsn_cnt;		/* Checkpoint buffers left to write. */
+
+	int	  ftype;		/* File type. */
+	int32_t	  lsn_off;		/* Page's LSN offset. */
+	u_int32_t clear_len;		/* Bytes to clear on page create. */
+
+	roff_t	  path_off;		/* File name location. */
+	roff_t	  fileid_off;		/* File identification location. */
+
+	roff_t	  pgcookie_len;		/* Pgin/pgout cookie length. */
+	roff_t	  pgcookie_off;		/* Pgin/pgout cookie location. */
+
+	db_pgno_t last_pgno;		/* Last page in the file. */
+	db_pgno_t orig_last_pgno;	/* Original last page in the file. */
+
+	DB_MPOOL_FSTAT stat;		/* Per-file mpool statistics. */
+
+#define	MP_CAN_MMAP	0x01		/* If the file can be mmap'd. */
+#define	MP_DEADFILE	0x02		/* Dirty pages can simply be trashed. */
+#define	MP_TEMP		0x04		/* Backing file is a temporary. */
+#define	MP_UNLINK	0x08		/* Unlink file on last close. */
+	u_int32_t  flags;
+};
+
+/*
+ * BH_TO_CACHE --
+ *	Return the cache where we can find the specified buffer header.
+ */
+#define	BH_TO_CACHE(dbmp, bhp)						\
+	(dbmp)->reginfo[NCACHE((dbmp)->reginfo[0].primary, (bhp)->pgno)].primary
+
+/*
+ * BH --
+ *	Buffer header.
+ */
+struct __bh {
+	MUTEX	        mutex;		/* Buffer thread/process 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_SYNC		0x010		/* memp sync: write the page */
+#define	BH_SYNC_LOGFLSH	0x020		/* memp sync: also flush the log */
+#define	BH_TRASH	0x040		/* Page is garbage. */
+	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. */
+	roff_t	  mf_offset;		/* Associated MPOOLFILE offset. */
+
+	/*
+	 * !!!
+	 * This array must be at least size_t aligned -- the DB access methods
+	 * put PAGE and other structures into it, and then access them directly.
+	 * (We guarantee size_t alignment to applications in the documentation,
+	 * too.)
+	 */
+	u_int8_t   buf[1];		/* Variable length data. */
+};
+
+#include "mp_ext.h"