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.Dd July 21, 2003 27.Dt VM_FAULT_PREFAULT 9 28.Os 29.Sh NAME 30.Nm vm_fault_prefault 31.Nd cluster page faults into a process's address space 32.Sh SYNOPSIS 33.In sys/param.h 34.In vm/vm.h 35.In vm/pmap.h 36.Ft void 37.Fn vm_fault_prefault "pmap_t pmap" "vm_offset_t addra" "vm_map_entry_t entry" 38.Sh DESCRIPTION 39The 40.Fn vm_fault_prefault 41function provides a means of clustering pagefaults into a process's 42address space. 43It operates upon the physical map 44.Fa pmap . 45The 46.Fa entry 47argument specifies the entry to be prefaulted; the 48.Fa addra 49argument specifies the beginning of the mapping in the process's virtual 50address space. 51.Pp 52It is typically called by 53.Fn vm_fault 54after the first page fault. 55It benefits the 56.Xr execve 2 57system call by eliminating repetitive calls to 58.Fn vm_fault , 59which would otherwise be made to bring the process's executable pages 60into physical memory. 61.Sh IMPLEMENTATION NOTES 62This is a machine-independent function which calls the machine-dependent 63.Xr pmap_is_prefaultable 9 64helper function to determine if a page may be prefaulted into physical memory. 65.Sh SEE ALSO 66.Xr execve 2 , 67.Xr pmap_is_prefaultable 9 68.Sh AUTHORS 69This manual page was written by 70.An Bruce M Simpson Aq Mt bms@spc.org . 71