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.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/
