ck_pr_fence_memory(3)
enforce partial ordering of all memory operations
LIBRARY
Concurrency Kit (libck, -lck)
SYNOPSIS
In ck_pr.h
Ft void
Fn ck_pr_fence_memory
Ft void
Fn ck_pr_fence_strict_memory
DESCRIPTION
The
Fn ck_pr_fence_memory 3
function enforces the ordering of any memory operations
with respect to the invocation of the function. This function
always serves as an implicit compiler barrier.
Achitectures implementing CK_MD_TSO do not emit
a barrier, but compiler barrier semantics remain.
Architectures implementing CK_MD_PSO and CK_MD_RMO always emit
an instructions which provides the specified ordering
guarantees. To force the unconditional emission of a memory
fence, use
Fn ck_pr_fence_strict_memory .
EXAMPLE
#include <ck_pr.h>
static int a = 0;
static int b;
static int c;
static int d;
void
function(void)
{
int snapshot_a;
ck_pr_store_int(&b, 1);
snapshot_a = ck_pr_load_int(&a);
/*
* Make sure previous memory operations are
* ordered with respect to memory operations
* following the ck_pr_fence_memory.
*/
ck_pr_fence_memory();
ck_pr_store_int(&d, 3);
ck_pr_store_int(&c, 2);
return;
}
RETURN VALUES
This function has no return value.