1.\" 2.\" Copyright (c) 2003 Bruce M Simpson <bms@spc.org> 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd July 21, 2003 29.Dt VM_FAULT_PREFAULT 9 30.Sh NAME 31.Nm vm_fault_prefault 32.Nd cluster page faults into a process's address space 33.Sh SYNOPSIS 34.In sys/param.h 35.In vm/vm.h 36.In vm/pmap.h 37.Ft void 38.Fn vm_map_prefault "pmap_t pmap" "vm_offset_t addra" "vm_map_entry_t entry" 39.Sh DESCRIPTION 40The 41.Fn vm_map_prefault 42function provides a means of clustering pagefaults into a process's 43address space. 44It operates upon the physical map 45.Fa pmap . 46The 47.Fa entry 48argument specifies the entry to be prefaulted; the 49.Fa addra 50argument specifies the beginning of the mapping in the process's virtual 51address space. 52.Pp 53It is typically called by 54.Fn vm_fault 55after the first page fault. 56It benefits the 57.Fn exec 58system call by eliminating repetitive calls to 59.Fn vm_fault , 60which would otherwise be made to bring the process's executable pages 61into physical memory. 62.Sh IMPLEMENTATION NOTES 63This is a machine-independent function which calls the machine-dependent 64.Fn pmap_is_prefaultable 65helper function to determine if a page may be prefaulted into physical memory. 66.Sh SEE ALSO 67.Xr execve 2 , 68.Xr pmap_is_prefaultable 9 69.Sh AUTHORS 70This manual page was written by 71.An Bruce M Simpson Aq bms@spc.org . 72