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.\"
.\" Copyright 2013 Samy Al Bahra.
.\" 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 REGENTS 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 REGENTS 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 May 16, 2013
.Dt CK_PR_FENCE_ATOMIC_LOAD 3
.Sh NAME
.Nm ck_pr_fence_atomic_load
.Nd enforce ordering of atomic read-modify-write operations to load operations
.Sh LIBRARY
Concurrency Kit (libck, \-lck)
.Sh SYNOPSIS
.In ck_pr.h
.Ft void
.Fn ck_pr_fence_atomic_load void
.Ft void
.Fn ck_pr_fence_strict_atomic_load void
.Sh DESCRIPTION
The
.Fn ck_pr_fence_atomic_load
function enforces the ordering of any
atomic read-modify-write operations relative to
any load operations following the function invocation. This function
always serve as an implicit compiler barrier. On
architectures implementing CK_MD_TSO, this operation
only serves as a compiler barrier and no fences
are emitted. To force the unconditional emission of
a fence, use
.Fn ck_pr_fence_strict_atomic_load .
.Sh EXAMPLE
.Bd -literal -offset indent
#include <ck_pr.h>
static int a = 0;
static int b = 0;
void
function(void)
{
int c;
ck_pr_fas_int(&a, 1);
/*
* Guarantee that the update to a is completed
* with respect to the load of *b.
*/
ck_pr_fence_atomic_load();
c = ck_pr_load_int(&b);
return;
}
.Ed
.Sh RETURN VALUES
This function has no return value.
.Sh SEE ALSO
.Xr ck_pr_stall 3 ,
.Xr ck_pr_fence_atomic 3 ,
.Xr ck_pr_fence_atomic_store 3 ,
.Xr ck_pr_fence_store 3 ,
.Xr ck_pr_fence_load 3 ,
.Xr ck_pr_fence_load_atomic 3 ,
.Xr ck_pr_fence_load_store 3 ,
.Xr ck_pr_fence_load_depends 3 ,
.Xr ck_pr_fence_memory 3 ,
.Xr ck_pr_barrier 3 ,
.Xr ck_pr_fas 3 ,
.Xr ck_pr_load 3 ,
.Xr ck_pr_store 3 ,
.Xr ck_pr_faa 3 ,
.Xr ck_pr_inc 3 ,
.Xr ck_pr_dec 3 ,
.Xr ck_pr_neg 3 ,
.Xr ck_pr_not 3 ,
.Xr ck_pr_add 3 ,
.Xr ck_pr_sub 3 ,
.Xr ck_pr_and 3 ,
.Xr ck_pr_or 3 ,
.Xr ck_pr_xor 3 ,
.Xr ck_pr_cas 3 ,
.Xr ck_pr_btc 3 ,
.Xr ck_pr_bts 3 ,
.Xr ck_pr_btr 3
.Pp
Additional information available at http://concurrencykit.org/
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