|Return to membar_ops.3 CVS log||Up to [cvs.NetBSD.org] / src / lib / libc / atomic|
|File: [cvs.NetBSD.org] / src / lib / libc / atomic / membar_ops.3 (download)
Revision 1.3, Thu Apr 28 11:56:26 2011 UTC (10 years, 8 months ago) by wiz
Fix a typo.
.\" $NetBSD: membar_ops.3,v 1.3 2011/04/28 11:56:26 wiz Exp $ .\" .\" Copyright (c) 2007, 2008 The NetBSD Foundation, Inc. .\" All rights reserved. .\" .\" This code is derived from software contributed to The NetBSD Foundation .\" by Jason R. Thorpe. .\" .\" 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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. .\" .Dd February 11, 2007 .Dt MEMBAR_OPS 3 .Os .Sh NAME .Nm membar_ops , .Nm membar_enter , .Nm membar_exit , .Nm membar_producer , .Nm membar_consumer , .Nm membar_sync .Nd memory access barrier operations .\" .Sh LIBRARY .\" .Lb libc .Sh SYNOPSIS .In sys/atomic.h .\" .Ft void .Fn membar_enter "void" .Ft void .Fn membar_exit "void" .Ft void .Fn membar_producer "void" .Ft void .Fn membar_consumer "void" .Ft void .Fn membar_sync "void" .Sh DESCRIPTION The .Nm membar_ops family of functions provide memory access barrier operations necessary for synchronization in multiprocessor execution environments that have relaxed load and store order. .Pp .Bl -tag -width "mem" .It Fn membar_enter Any store preceding .Fn membar_enter will reach global visibility before all loads and stores following it. .Pp .Fn membar_enter is typically used in code that implements locking primitives to ensure that a lock protects its data. .It Fn membar_exit All loads and stores preceding .Fn membar_exit will reach global visibility before any store that follows it. .Pp .Fn membar_exit is typically used in code that implements locking primitives to ensure that a lock protects its data. .It Fn membar_producer All stores preceding the memory barrier will reach global visibility before any stores after the memory barrier reach global visibility. .It Fn membar_consumer All loads preceding the memory barrier will complete before any loads after the memory barrier complete. .It Fn membar_sync All loads and stores preceding the memory barrier will complete and reach global visibility before any loads and stores after the memory barrier complete and reach global visibility. .El .Sh SEE ALSO .Xr atomic_ops 3 .Sh HISTORY The .Nm membar_ops functions first appeared in .Nx 5.0 .