2003-10-04 01:30:01 +00:00
|
|
|
.\"
|
|
|
|
.\" Copyright (c) 2003 Bruce M Simpson <bms@spc.org>
|
|
|
|
.\" 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.
|
|
|
|
.\"
|
|
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
|
|
|
|
.\"
|
|
|
|
.\" $FreeBSD$
|
|
|
|
.\"
|
|
|
|
.Dd July 21, 2003
|
|
|
|
.Dt VM_FAULT_PREFAULT 9
|
|
|
|
.Sh NAME
|
|
|
|
.Nm vm_fault_prefault
|
|
|
|
.Nd cluster page faults into a process's address space
|
|
|
|
.Sh SYNOPSIS
|
|
|
|
.In sys/param.h
|
|
|
|
.In vm/vm.h
|
|
|
|
.In vm/pmap.h
|
|
|
|
.Ft void
|
|
|
|
.Fn vm_map_prefault "pmap_t pmap" "vm_offset_t addra" "vm_map_entry_t entry"
|
|
|
|
.Sh DESCRIPTION
|
|
|
|
The
|
|
|
|
.Fn vm_map_prefault
|
|
|
|
function provides a means of clustering pagefaults into a process's
|
|
|
|
address space.
|
|
|
|
It operates upon the physical map
|
|
|
|
.Fa pmap .
|
|
|
|
The
|
|
|
|
.Fa entry
|
|
|
|
argument specifies the entry to be prefaulted; the
|
|
|
|
.Fa addra
|
|
|
|
argument specifies the beginning of the mapping in the process's virtual
|
|
|
|
address space.
|
|
|
|
.Pp
|
|
|
|
It is typically called by
|
|
|
|
.Fn vm_fault
|
|
|
|
after the first page fault.
|
|
|
|
It benefits the
|
|
|
|
.Fn exec
|
|
|
|
system call by eliminating repetitive calls to
|
|
|
|
.Fn vm_fault ,
|
|
|
|
which would otherwise be made to bring the process's executable pages
|
|
|
|
into physical memory.
|
|
|
|
.Sh IMPLEMENTATION NOTES
|
|
|
|
This is a machine-independent function which calls the machine-dependent
|
|
|
|
.Fn pmap_is_prefaultable
|
2003-10-05 11:47:51 +00:00
|
|
|
helper function to determine if a page may be prefaulted into physical memory.
|
2003-10-04 01:30:01 +00:00
|
|
|
.Sh SEE ALSO
|
|
|
|
.Xr execve 2 ,
|
|
|
|
.Xr pmap_is_prefaultable 9
|
|
|
|
.Sh AUTHORS
|
|
|
|
This manual page was written by
|
|
|
|
.An Bruce M Simpson Aq bms@spc.org .
|