freebsd-nq/sys/i386/include/param.h
David Greenman 04f1835605 1) "Pre-faulting" in of pages into process address space
Eliminates vm_fault overhead on process startup and
		mmap referenced data for in-memory pages.

		(process startup time using in-memory segments *much* faster)

	2)	Even more efficient pmap code.  Code partially cleaned up.
		More comments yet to follow.

		(generally more efficient pte management)

	3)	Pageout clustering ( in addition to the FreeBSD V1.1 pagein
		clustering.)

		(much faster paging performance on non-write behind disk
		subsystems, slightly faster performance on other systems.)

	4)	Slightly changed vm_pageout code for more efficiency and
		better statistics.  Also, resist swapout a little more.

		(less likely to pageout a recently used page)

	5)	Slight improvement to the page table page trap efficiency.

		(generally faster system VM fault performance)

	6)	Defer creation of unnamed anonymous regions pager until needed.

		(speeds up shared memory bss creation)

	7)	Remove possible deadlock from swap_pager initialization.

	8)	Enhanced procfs to provide "vminfo" about vm objects and user
		pmaps.

	9)	Increased MCLSHIFT/MCLBYTES from 2K to 4K to improve net &
		socket performance and to prepare for things to come.

John Dyson
dyson@implode.root.com
David Greenman
davidg@root.com
1994-03-07 11:38:49 +00:00

168 lines
6.0 KiB
C

/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* 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.
*
* from: @(#)param.h 5.8 (Berkeley) 6/28/91
* $Id: param.h,v 1.13 1994/01/31 04:18:54 davidg Exp $
*/
#ifndef _MACHINE_PARAM_H_
#define _MACHINE_PARAM_H_ 1
/*
* Machine dependent constants for Intel 386.
*/
#define MACHINE "i386"
#define MID_MACHINE MID_I386
/*
* Round p (pointer or byte index) up to a correctly-aligned value
* for all data types (int, long, ...). The result is u_int and
* must be cast to any desired pointer type.
*/
#define ALIGNBYTES (sizeof(int) - 1)
#define ALIGN(p) (((u_int)(p) + ALIGNBYTES) &~ ALIGNBYTES)
/* XXX PGSHIFT and PG_SHIFT are two names for the same thing */
#define PGSHIFT 12 /* LOG2(NBPG) */
#define PAGE_SHIFT 12
#define NBPG (1 << PAGE_SHIFT) /* bytes/page */
#define PAGE_SIZE (1 << PAGE_SHIFT)
#define PAGE_MASK (PAGE_SIZE-1)
#define PGOFSET (NBPG-1) /* byte offset into page */
#define NPTEPG (NBPG/(sizeof (pt_entry_t)))
/* XXX PDRSHIFT and PD_SHIFT are two names for the same thing */
#define PDRSHIFT 22 /* LOG2(NBPDR) */
#define NBPDR (1 << PDRSHIFT) /* bytes/page dir */
#define PDROFSET (NBPDR-1) /* byte offset into page dir */
/*
* XXX This should really be KPTDPTDI << PDRSHIFT, but since KPTDPTDI is
* defined in pmap.h which is included after this we can't do that
* (YET!)
*/
#define BTOPKERNBASE (KERNBASE >> PGSHIFT)
#define DEV_BSHIFT 9 /* log2(DEV_BSIZE) */
#define DEV_BSIZE (1 << DEV_BSHIFT)
#define BLKDEV_IOSIZE 2048
#define MAXPHYS (64 * 1024) /* max raw I/O transfer size */
#define CLSIZELOG2 0
#define CLSIZE (1 << CLSIZELOG2)
/* NOTE: SSIZE, SINCR and UPAGES must be multiples of CLSIZE */
#define SSIZE 1 /* initial stack size/NBPG */
#define SINCR 1 /* increment of stack/NBPG */
#define UPAGES 2 /* pages of u-area */
/*
* Constants related to network buffer management.
* MCLBYTES must be no larger than CLBYTES (the software page size), and,
* on machines that exchange pages of input or output buffers with mbuf
* clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
* of the hardware page size.
*/
#ifndef MSIZE
#define MSIZE 128 /* size of an mbuf */
#endif /* MSIZE */
#ifndef MCLSHIFT
#define MCLSHIFT 12 /* convert bytes to m_buf clusters */
#endif /* MCLSHIFT */
#define MCLBYTES (1 << MCLSHIFT) /* size of an m_buf cluster */
#define MCLOFSET (MCLBYTES - 1) /* offset within an m_buf cluster */
#ifndef NMBCLUSTERS
#ifdef GATEWAY
#define NMBCLUSTERS 512 /* map size, max cluster allocation */
#else
#define NMBCLUSTERS 256 /* map size, max cluster allocation */
#endif /* GATEWAY */
#endif /* NMBCLUSTERS */
/*
* Some macros for units conversion
*/
/* Core clicks (4096 bytes) to segments and vice versa */
#define ctos(x) (x)
#define stoc(x) (x)
/* Core clicks (4096 bytes) to disk blocks */
#define ctod(x) ((x)<<(PGSHIFT-DEV_BSHIFT))
#define dtoc(x) ((x)>>(PGSHIFT-DEV_BSHIFT))
#define dtob(x) ((x)<<DEV_BSHIFT)
/* clicks to bytes */
#define ctob(x) ((x)<<PGSHIFT)
/* bytes to clicks */
#define btoc(x) (((unsigned)(x)+(NBPG-1))>>PGSHIFT)
#define btodb(bytes) /* calculates (bytes / DEV_BSIZE) */ \
((unsigned)(bytes) >> DEV_BSHIFT)
#define dbtob(db) /* calculates (db * DEV_BSIZE) */ \
((unsigned)(db) << DEV_BSHIFT)
/*
* Map a ``block device block'' to a file system block.
* This should be device dependent, and will be if we
* add an entry to cdevsw/bdevsw for that purpose.
* For now though just use DEV_BSIZE.
*/
#define bdbtofsb(bn) ((bn) / (BLKDEV_IOSIZE/DEV_BSIZE))
/*
* Mach derived conversion macros
*/
#define trunc_page(x) ((unsigned)(x) & ~(NBPG-1))
#define round_page(x) ((((unsigned)(x)) + NBPG - 1) & ~(NBPG-1))
#define atop(x) ((unsigned)(x) >> PG_SHIFT)
#define ptoa(x) ((unsigned)(x) << PG_SHIFT)
#define i386_round_pdr(x) ((((unsigned)(x)) + NBPDR - 1) & ~(NBPDR-1))
#define i386_trunc_pdr(x) ((unsigned)(x) & ~(NBPDR-1))
#define i386_round_page(x) ((((unsigned)(x)) + NBPG - 1) & ~(NBPG-1))
#define i386_trunc_page(x) ((unsigned)(x) & ~(NBPG-1))
#define i386_btod(x) ((unsigned)(x) >> PDRSHIFT)
#define i386_dtob(x) ((unsigned)(x) << PDRSHIFT)
#define i386_btop(x) ((unsigned)(x) >> PGSHIFT)
#define i386_ptob(x) ((unsigned)(x) << PGSHIFT)
#endif /* _MACHINE_PARAM_H_ */