119 lines
3.4 KiB
Groff
119 lines
3.4 KiB
Groff
.\"
|
|
.\" 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 19, 2003
|
|
.Dt vm_map_lock 9
|
|
.Sh NAME
|
|
.Nm vm_map_lock ,
|
|
.Nm vm_map_unlock ,
|
|
.Nm vm_map_lock_read ,
|
|
.Nm vm_map_unlock_read ,
|
|
.Nm vm_map_trylock ,
|
|
.Nm vm_map_trylock_read ,
|
|
.Nm vm_map_lock_upgrade ,
|
|
.Nm vm_map_lock_downgrade
|
|
.Nd vm_map locking macros
|
|
.Sh SYNOPSIS
|
|
.In sys/param.h
|
|
.In vm/vm.h
|
|
.In vm/vm_map.h
|
|
.Ft void
|
|
.Fn vm_map_lock "vm_map_t map"
|
|
.Ft void
|
|
.Fn vm_map_unlock "vm_map_t map"
|
|
.Ft void
|
|
.Fn vm_map_lock_read "vm_map_t map"
|
|
.Ft void
|
|
.Fn vm_map_unlock_read "vm_map_t map"
|
|
.Ft int
|
|
.Fn vm_map_trylock "vm_map_t map"
|
|
.Ft int
|
|
.Fn vm_map_trylock_read "vm_map_t map"
|
|
.Ft int
|
|
.Fn vm_map_lock_upgrade "vm_map_t map"
|
|
.Ft int
|
|
.Fn vm_map_lock_downgrade "vm_map_t map"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn vm_map_lock
|
|
macro obtains an exclusive lock on
|
|
.Fa map .
|
|
.Pp
|
|
The
|
|
.Fn vm_map_unlock
|
|
macro releases an exclusive lock on
|
|
.Fa map .
|
|
.Pp
|
|
The
|
|
.Fn vm_map_lock_read
|
|
macro obtains a read-lock on
|
|
.Fa map .
|
|
Currently this is implemented as an exclusive lock.
|
|
.Pp
|
|
The
|
|
.Fn vm_map_unlock_read
|
|
macro releases a read-lock on
|
|
.Fa map .
|
|
.Pp
|
|
The
|
|
.Fn vm_map_trylock
|
|
macro attempts to obtain an exclusive lock on
|
|
.Fa map .
|
|
It returns FALSE if the lock cannot be immediately acquired;
|
|
otherwise return TRUE with the lock acquired.
|
|
.Pp
|
|
The
|
|
.Fn vm_map_trylock_read
|
|
macro attempts to obtain a read-lock on
|
|
.Fa map .
|
|
It returns FALSE if the lock cannot be immediately acquired;
|
|
otherwise return TRUE with the lock acquired.
|
|
Currently this is implemented as an exclusive lock.
|
|
.Pp
|
|
The
|
|
.Fn vm_map_lock_upgrade
|
|
macro attempts to atomically upgrade a read-lock on
|
|
.Fa map
|
|
to an exclusive lock.
|
|
As read-locks are currently implemented as exclusive locks,
|
|
this macro is a no-op.
|
|
.Pp
|
|
The
|
|
.Fn vm_map_lock_downgrade
|
|
macro attempts to downgrade an exclusive lock on
|
|
.Fa map
|
|
to a read-lock.
|
|
As read-locks are currently implemented as exclusive locks,
|
|
this macro is a no-op.
|
|
.Sh IMPLEMENTATION NOTES
|
|
Currently, all of the locking macros implement their locks as sleep locks.
|
|
.Sh SEE ALSO
|
|
.Xr vm_map 9
|
|
.Sh AUTHORS
|
|
This man page was written by
|
|
.An Bruce M Simpson Aq bms@spc.org .
|