diff options
Diffstat (limited to 'db/mpool/mpool.c')
| -rw-r--r-- | db/mpool/mpool.c | 493 |
1 files changed, 0 insertions, 493 deletions
diff --git a/db/mpool/mpool.c b/db/mpool/mpool.c deleted file mode 100644 index 7ced76fd4f..0000000000 --- a/db/mpool/mpool.c +++ /dev/null @@ -1,493 +0,0 @@ -/*- - * Copyright (c) 1990, 1993, 1994 - * The Regents of the University of California. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#if defined(LIBC_SCCS) && !defined(lint) -static char sccsid[] = "@(#)mpool.c 8.5 (Berkeley) 7/26/94"; -#endif /* LIBC_SCCS and not lint */ - -#include <sys/param.h> -#include <sys/queue.h> -#include <sys/stat.h> - -#include <errno.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> - -#include <db.h> - -#define __MPOOLINTERFACE_PRIVATE -#include <mpool.h> - -#ifdef _LIBC -/* In the GNU C library we must not pollute the namespace because libdb is - needed by libnss_db. */ -#define mpool_open __mpool_open -#define mpool_filter __mpool_filter -#define mpool_new __mpool_new -#define mpool_get __mpool_get -#define mpool_put __mpool_put -#define mpool_sync __mpool_sync -#define mpool_close __mpool_close -#endif - -static BKT *mpool_bkt __P((MPOOL *)); -static BKT *mpool_look __P((MPOOL *, pgno_t)); -static int mpool_write __P((MPOOL *, BKT *)); - -/* - * mpool_open -- - * Initialize a memory pool. - */ -MPOOL * -mpool_open(key, fd, pagesize, maxcache) - void *key; - int fd; - pgno_t pagesize, maxcache; -{ - struct stat sb; - MPOOL *mp; - int entry; - - /* - * Get information about the file. - * - * XXX - * We don't currently handle pipes, although we should. - */ - if (fstat(fd, &sb)) - return (NULL); - if (!S_ISREG(sb.st_mode)) { - errno = ESPIPE; - return (NULL); - } - - /* Allocate and initialize the MPOOL cookie. */ - if ((mp = (MPOOL *)calloc(1, sizeof(MPOOL))) == NULL) - return (NULL); - CIRCLEQ_INIT(&mp->lqh); - for (entry = 0; entry < HASHSIZE; ++entry) - CIRCLEQ_INIT(&mp->hqh[entry]); - mp->maxcache = maxcache; - mp->npages = sb.st_size / pagesize; - mp->pagesize = pagesize; - mp->fd = fd; - return (mp); -} - -/* - * mpool_filter -- - * Initialize input/output filters. - */ -void -mpool_filter(mp, pgin, pgout, pgcookie) - MPOOL *mp; - void (*pgin) __P((void *, pgno_t, void *)); - void (*pgout) __P((void *, pgno_t, void *)); - void *pgcookie; -{ - mp->pgin = pgin; - mp->pgout = pgout; - mp->pgcookie = pgcookie; -} - -/* - * mpool_new -- - * Get a new page of memory. - */ -void * -mpool_new(mp, pgnoaddr) - MPOOL *mp; - pgno_t *pgnoaddr; -{ - struct _hqh *head; - BKT *bp; - - if (mp->npages == MAX_PAGE_NUMBER) { - (void)fprintf(stderr, "mpool_new: page allocation overflow.\n"); - abort(); - } -#ifdef STATISTICS - ++mp->pagenew; -#endif - /* - * Get a BKT from the cache. Assign a new page number, attach - * it to the head of the hash chain, the tail of the lru chain, - * and return. - */ - if ((bp = mpool_bkt(mp)) == NULL) - return (NULL); - *pgnoaddr = bp->pgno = mp->npages++; - bp->flags = MPOOL_PINNED; - - head = &mp->hqh[HASHKEY(bp->pgno)]; - CIRCLEQ_INSERT_HEAD(head, bp, hq); - CIRCLEQ_INSERT_TAIL(&mp->lqh, bp, q); - return (bp->page); -} - -/* - * mpool_get - * Get a page. - */ -void * -mpool_get(mp, pgno, flags) - MPOOL *mp; - pgno_t pgno; - u_int flags; /* XXX not used? */ -{ - struct _hqh *head; - BKT *bp; - off_t off; - int nr; - - /* Check for attempt to retrieve a non-existent page. */ - if (pgno >= mp->npages) { - errno = EINVAL; - return (NULL); - } - -#ifdef STATISTICS - ++mp->pageget; -#endif - - /* Check for a page that is cached. */ - if ((bp = mpool_look(mp, pgno)) != NULL) { -#ifdef DEBUG - if (bp->flags & MPOOL_PINNED) { - (void)fprintf(stderr, - "mpool_get: page %d already pinned\n", bp->pgno); - abort(); - } -#endif - /* - * Move the page to the head of the hash chain and the tail - * of the lru chain. - */ - head = &mp->hqh[HASHKEY(bp->pgno)]; - CIRCLEQ_REMOVE(head, bp, hq); - CIRCLEQ_INSERT_HEAD(head, bp, hq); - CIRCLEQ_REMOVE(&mp->lqh, bp, q); - CIRCLEQ_INSERT_TAIL(&mp->lqh, bp, q); - - /* Return a pinned page. */ - bp->flags |= MPOOL_PINNED; - return (bp->page); - } - - /* Get a page from the cache. */ - if ((bp = mpool_bkt(mp)) == NULL) - return (NULL); - - /* Read in the contents. */ -#ifdef STATISTICS - ++mp->pageread; -#endif - off = mp->pagesize * pgno; - if (lseek(mp->fd, off, SEEK_SET) != off) - return (NULL); - if ((u_long) (nr = read(mp->fd, bp->page, mp->pagesize)) - != mp->pagesize) { - if (nr >= 0) - errno = EFTYPE; - return (NULL); - } - - /* Set the page number, pin the page. */ - bp->pgno = pgno; - bp->flags = MPOOL_PINNED; - - /* - * Add the page to the head of the hash chain and the tail - * of the lru chain. - */ - head = &mp->hqh[HASHKEY(bp->pgno)]; - CIRCLEQ_INSERT_HEAD(head, bp, hq); - CIRCLEQ_INSERT_TAIL(&mp->lqh, bp, q); - - /* Run through the user's filter. */ - if (mp->pgin != NULL) - (mp->pgin)(mp->pgcookie, bp->pgno, bp->page); - - return (bp->page); -} - -/* - * mpool_put - * Return a page. - */ -int -mpool_put(mp, page, flags) - MPOOL *mp; - void *page; - u_int flags; -{ - BKT *bp; - -#ifdef STATISTICS - ++mp->pageput; -#endif - bp = (BKT *)((char *)page - sizeof(BKT)); -#ifdef DEBUG - if (!(bp->flags & MPOOL_PINNED)) { - (void)fprintf(stderr, - "mpool_put: page %d not pinned\n", bp->pgno); - abort(); - } -#endif - bp->flags &= ~MPOOL_PINNED; - bp->flags |= flags & MPOOL_DIRTY; - return (RET_SUCCESS); -} - -/* - * mpool_close - * Close the buffer pool. - */ -int -mpool_close(mp) - MPOOL *mp; -{ - BKT *bp; - - /* Free up any space allocated to the lru pages. */ - while ((bp = mp->lqh.cqh_first) != (void *)&mp->lqh) { - CIRCLEQ_REMOVE(&mp->lqh, mp->lqh.cqh_first, q); - free(bp); - } - - /* Free the MPOOL cookie. */ - free(mp); - return (RET_SUCCESS); -} - -/* - * mpool_sync - * Sync the pool to disk. - */ -int -mpool_sync(mp) - MPOOL *mp; -{ - BKT *bp; - - /* Walk the lru chain, flushing any dirty pages to disk. */ - for (bp = mp->lqh.cqh_first; - bp != (void *)&mp->lqh; bp = bp->q.cqe_next) - if (bp->flags & MPOOL_DIRTY && - mpool_write(mp, bp) == RET_ERROR) - return (RET_ERROR); - - /* Sync the file descriptor. */ - return (fsync(mp->fd) ? RET_ERROR : RET_SUCCESS); -} - -#ifdef _LIBC -#undef mpool_open -#undef mpool_filter -#undef mpool_new -#undef mpool_get -#undef mpool_put -#undef mpool_close -#undef mpool_sync -weak_alias (__mpool_open, mpool_open) -weak_alias (__mpool_filter, mpool_filter) -weak_alias (__mpool_new, mpool_new) -weak_alias (__mpool_get, mpool_get) -weak_alias (__mpool_put, mpool_put) -weak_alias (__mpool_close, mpool_close) -weak_alias (__mpool_sync, mpool_sync) -#endif - -/* - * mpool_bkt - * Get a page from the cache (or create one). - */ -static BKT * -mpool_bkt(mp) - MPOOL *mp; -{ - struct _hqh *head; - BKT *bp; - - /* If under the max cached, always create a new page. */ - if (mp->curcache < mp->maxcache) - goto new; - - /* - * If the cache is max'd out, walk the lru list for a buffer we - * can flush. If we find one, write it (if necessary) and take it - * off any lists. If we don't find anything we grow the cache anyway. - * The cache never shrinks. - */ - for (bp = mp->lqh.cqh_first; - bp != (void *)&mp->lqh; bp = bp->q.cqe_next) - if (!(bp->flags & MPOOL_PINNED)) { - /* Flush if dirty. */ - if (bp->flags & MPOOL_DIRTY && - mpool_write(mp, bp) == RET_ERROR) - return (NULL); -#ifdef STATISTICS - ++mp->pageflush; -#endif - /* Remove from the hash and lru queues. */ - head = &mp->hqh[HASHKEY(bp->pgno)]; - CIRCLEQ_REMOVE(head, bp, hq); - CIRCLEQ_REMOVE(&mp->lqh, bp, q); -#ifdef DEBUG - { void *spage; - spage = bp->page; - memset(bp, 0xff, sizeof(BKT) + mp->pagesize); - bp->page = spage; - } -#endif - return (bp); - } - -new: if ((bp = (BKT *)malloc(sizeof(BKT) + mp->pagesize)) == NULL) - return (NULL); -#ifdef STATISTICS - ++mp->pagealloc; -#endif -#if defined(DEBUG) || defined(PURIFY) - memset(bp, 0xff, sizeof(BKT) + mp->pagesize); -#endif - bp->page = (char *)bp + sizeof(BKT); - ++mp->curcache; - return (bp); -} - -/* - * mpool_write - * Write a page to disk. - */ -static int -mpool_write(mp, bp) - MPOOL *mp; - BKT *bp; -{ - off_t off; - -#ifdef STATISTICS - ++mp->pagewrite; -#endif - - /* Run through the user's filter. */ - if (mp->pgout) - (mp->pgout)(mp->pgcookie, bp->pgno, bp->page); - - off = mp->pagesize * bp->pgno; - if (lseek(mp->fd, off, SEEK_SET) != off) - return (RET_ERROR); - if ((u_long) write(mp->fd, bp->page, mp->pagesize) != mp->pagesize) - return (RET_ERROR); - - bp->flags &= ~MPOOL_DIRTY; - return (RET_SUCCESS); -} - -/* - * mpool_look - * Lookup a page in the cache. - */ -static BKT * -mpool_look(mp, pgno) - MPOOL *mp; - pgno_t pgno; -{ - struct _hqh *head; - BKT *bp; - - head = &mp->hqh[HASHKEY(pgno)]; - for (bp = head->cqh_first; bp != (void *)head; bp = bp->hq.cqe_next) - if (bp->pgno == pgno) { -#ifdef STATISTICS - ++mp->cachehit; -#endif - return (bp); - } -#ifdef STATISTICS - ++mp->cachemiss; -#endif - return (NULL); -} - -#ifdef STATISTICS -/* - * mpool_stat - * Print out cache statistics. - */ -void -mpool_stat(mp) - MPOOL *mp; -{ - BKT *bp; - int cnt; - char *sep; - - (void)fprintf(stderr, "%lu pages in the file\n", mp->npages); - (void)fprintf(stderr, - "page size %lu, cacheing %lu pages of %lu page max cache\n", - mp->pagesize, mp->curcache, mp->maxcache); - (void)fprintf(stderr, "%lu page puts, %lu page gets, %lu page new\n", - mp->pageput, mp->pageget, mp->pagenew); - (void)fprintf(stderr, "%lu page allocs, %lu page flushes\n", - mp->pagealloc, mp->pageflush); - if (mp->cachehit + mp->cachemiss) - (void)fprintf(stderr, - "%.0f%% cache hit rate (%lu hits, %lu misses)\n", - ((double)mp->cachehit / (mp->cachehit + mp->cachemiss)) - * 100, mp->cachehit, mp->cachemiss); - (void)fprintf(stderr, "%lu page reads, %lu page writes\n", - mp->pageread, mp->pagewrite); - - sep = ""; - cnt = 0; - for (bp = mp->lqh.cqh_first; - bp != (void *)&mp->lqh; bp = bp->q.cqe_next) { - (void)fprintf(stderr, "%s%d", sep, bp->pgno); - if (bp->flags & MPOOL_DIRTY) - (void)fprintf(stderr, "d"); - if (bp->flags & MPOOL_PINNED) - (void)fprintf(stderr, "P"); - if (++cnt == 10) { - sep = "\n"; - cnt = 0; - } else - sep = ", "; - - } - (void)fprintf(stderr, "\n"); -} -#endif |