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[src/trunk]: src/lib/libbsdmalloc Adding libbsdmalloc which is Chris Kingsley...
details: https://anonhg.NetBSD.org/src/rev/0b4d8a574f87
branches: trunk
changeset: 546177:0b4d8a574f87
user: elric <elric%NetBSD.org@localhost>
date: Mon Apr 21 22:21:06 2003 +0000
description:
Adding libbsdmalloc which is Chris Kingsley's `power of two bucket' malloc.
Suggested by christos.
diffstat:
lib/libbsdmalloc/Makefile | 13 +
lib/libbsdmalloc/malloc.c | 499 +++++++++++++++++++++++++++++++++++++++++
lib/libbsdmalloc/shlib_version | 5 +
3 files changed, 517 insertions(+), 0 deletions(-)
diffs (truncated from 529 to 300 lines):
diff -r f076c6061922 -r 0b4d8a574f87 lib/libbsdmalloc/Makefile
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/libbsdmalloc/Makefile Mon Apr 21 22:21:06 2003 +0000
@@ -0,0 +1,13 @@
+# $NetBSD: Makefile,v 1.1 2003/04/21 22:21:06 elric Exp $
+
+.include <bsd.own.mk>
+
+LIB= bsdmalloc
+SRCS= malloc.c
+
+CPPFLAGS= -D_REENTRANT
+CPPFLAGS= -I${.CURDIR}/../libc/include/
+
+NOMAN=1
+
+.include <bsd.lib.mk>
diff -r f076c6061922 -r 0b4d8a574f87 lib/libbsdmalloc/malloc.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/libbsdmalloc/malloc.c Mon Apr 21 22:21:06 2003 +0000
@@ -0,0 +1,499 @@
+/* $NetBSD: malloc.c,v 1.1 2003/04/21 22:21:06 elric Exp $ */
+
+/*
+ * Copyright (c) 1983, 1993
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+#if defined(LIBC_SCCS) && !defined(lint)
+#if 0
+static char sccsid[] = "@(#)malloc.c 8.1 (Berkeley) 6/4/93";
+#else
+__RCSID("$NetBSD: malloc.c,v 1.1 2003/04/21 22:21:06 elric Exp $");
+#endif
+#endif /* LIBC_SCCS and not lint */
+
+/*
+ * malloc.c (Caltech) 2/21/82
+ * Chris Kingsley, kingsley@cit-20.
+ *
+ * This is a very fast storage allocator. It allocates blocks of a small
+ * number of different sizes, and keeps free lists of each size. Blocks that
+ * don't exactly fit are passed up to the next larger size. In this
+ * implementation, the available sizes are 2^n-4 (or 2^n-10) bytes long.
+ * This is designed for use in a virtual memory environment.
+ */
+
+#include <sys/types.h>
+#if defined(DEBUG) || defined(RCHECK)
+#include <sys/uio.h>
+#endif
+#if defined(RCHECK) || defined(MSTATS)
+#include <stdio.h>
+#endif
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include "reentrant.h"
+
+
+/*
+ * The overhead on a block is at least 4 bytes. When free, this space
+ * contains a pointer to the next free block, and the bottom two bits must
+ * be zero. When in use, the first byte is set to MAGIC, and the second
+ * byte is the size index. The remaining bytes are for alignment.
+ * If range checking is enabled then a second word holds the size of the
+ * requested block, less 1, rounded up to a multiple of sizeof(RMAGIC).
+ * The order of elements is critical: ov_magic must overlay the low order
+ * bits of ov_next, and ov_magic can not be a valid ov_next bit pattern.
+ */
+union overhead {
+ union overhead *ov_next; /* when free */
+ struct {
+ u_char ovu_magic; /* magic number */
+ u_char ovu_index; /* bucket # */
+#ifdef RCHECK
+ u_short ovu_rmagic; /* range magic number */
+ u_long ovu_size; /* actual block size */
+#endif
+ } ovu;
+#define ov_magic ovu.ovu_magic
+#define ov_index ovu.ovu_index
+#define ov_rmagic ovu.ovu_rmagic
+#define ov_size ovu.ovu_size
+};
+
+#define MAGIC 0xef /* magic # on accounting info */
+#ifdef RCHECK
+#define RMAGIC 0x5555 /* magic # on range info */
+#endif
+
+#ifdef RCHECK
+#define RSLOP sizeof (u_short)
+#else
+#define RSLOP 0
+#endif
+
+/*
+ * nextf[i] is the pointer to the next free block of size 2^(i+3). The
+ * smallest allocatable block is 8 bytes. The overhead information
+ * precedes the data area returned to the user.
+ */
+#define NBUCKETS 30
+static union overhead *nextf[NBUCKETS];
+
+static long pagesz; /* page size */
+static int pagebucket; /* page size bucket */
+
+#ifdef MSTATS
+/*
+ * nmalloc[i] is the difference between the number of mallocs and frees
+ * for a given block size.
+ */
+static u_int nmalloc[NBUCKETS];
+#endif
+
+#ifdef _REENT
+static mutex_t malloc_mutex = MUTEX_INITIALIZER;
+#endif
+
+static void morecore __P((int));
+static int findbucket __P((union overhead *, int));
+#ifdef MSTATS
+void mstats __P((const char *));
+#endif
+
+#if defined(DEBUG) || defined(RCHECK)
+#define ASSERT(p) if (!(p)) botch(__STRING(p))
+
+static void botch __P((const char *));
+
+/*
+ * NOTE: since this may be called while malloc_mutex is locked, stdio must not
+ * be used in this function.
+ */
+static void
+botch(s)
+ const char *s;
+{
+ struct iovec iov[3];
+
+ iov[0].iov_base = "\nassertion botched: ";
+ iov[0].iov_len = 20;
+ iov[1].iov_base = (void *)s;
+ iov[1].iov_len = strlen(s);
+ iov[2].iov_base = "\n";
+ iov[2].iov_len = 1;
+
+ /*
+ * This place deserves a word of warning: a cancellation point will
+ * occur when executing writev(), and we might be still owning
+ * malloc_mutex. At this point we need to disable cancellation
+ * until `after' abort() because i) establishing a cancellation handler
+ * might, depending on the implementation, result in another malloc()
+ * to be executed, and ii) it is really not desirable to let execution
+ * continue. `Fix me.'
+ *
+ * Note that holding mutex_lock during abort() is safe.
+ */
+
+ (void)writev(STDERR_FILENO, iov, 3);
+ abort();
+}
+#else
+#define ASSERT(p)
+#endif
+
+void *
+malloc(nbytes)
+ size_t nbytes;
+{
+ union overhead *op;
+ int bucket;
+ long n;
+ unsigned amt;
+
+ mutex_lock(&malloc_mutex);
+
+ /*
+ * First time malloc is called, setup page size and
+ * align break pointer so all data will be page aligned.
+ */
+ if (pagesz == 0) {
+ pagesz = n = getpagesize();
+ ASSERT(pagesz > 0);
+ op = (union overhead *)(void *)sbrk(0);
+ n = n - sizeof (*op) - ((long)op & (n - 1));
+ if (n < 0)
+ n += pagesz;
+ if (n) {
+ if (sbrk((int)n) == (void *)-1) {
+ mutex_unlock(&malloc_mutex);
+ return (NULL);
+ }
+ }
+ bucket = 0;
+ amt = 8;
+ while (pagesz > amt) {
+ amt <<= 1;
+ bucket++;
+ }
+ pagebucket = bucket;
+ }
+ /*
+ * Convert amount of memory requested into closest block size
+ * stored in hash buckets which satisfies request.
+ * Account for space used per block for accounting.
+ */
+ if (nbytes <= (n = pagesz - sizeof (*op) - RSLOP)) {
+#ifndef RCHECK
+ amt = 8; /* size of first bucket */
+ bucket = 0;
+#else
+ amt = 16; /* size of first bucket */
+ bucket = 1;
+#endif
+ n = -((long)sizeof (*op) + RSLOP);
+ } else {
+ amt = (unsigned)pagesz;
+ bucket = pagebucket;
+ }
+ while (nbytes > amt + n) {
+ amt <<= 1;
+ if (amt == 0)
+ return (NULL);
+ bucket++;
+ }
+ /*
+ * If nothing in hash bucket right now,
+ * request more memory from the system.
+ */
+ if ((op = nextf[bucket]) == NULL) {
+ morecore(bucket);
+ if ((op = nextf[bucket]) == NULL) {
+ mutex_unlock(&malloc_mutex);
+ return (NULL);
+ }
+ }
+ /* remove from linked list */
+ nextf[bucket] = op->ov_next;
+ op->ov_magic = MAGIC;
+ op->ov_index = bucket;
+#ifdef MSTATS
+ nmalloc[bucket]++;
+#endif
+ mutex_unlock(&malloc_mutex);
+#ifdef RCHECK
+ /*
+ * Record allocated size of block and
+ * bound space with magic numbers.
+ */
+ op->ov_size = (nbytes + RSLOP - 1) & ~(RSLOP - 1);
+ op->ov_rmagic = RMAGIC;
+ *(u_short *)((caddr_t)(op + 1) + op->ov_size) = RMAGIC;
+#endif
+ return ((void *)(op + 1));
+}
+
+/*
+ * Allocate more memory to the indicated bucket.
+ */
+static void
+morecore(bucket)
+ int bucket;
+{
+ union overhead *op;
+ long sz; /* size of desired block */
+ long amt; /* amount to allocate */
+ long nblks; /* how many blocks we get */
+
+ /*
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