NAME

ck_pr_fence_atomic — enforce partial ordering of atomic read-modify-write operations

LIBRARY

Concurrency Kit (libck, -lck)

SYNOPSIS

#include <ck_pr.h>

void
ck_pr_fence_atomic(void);

void
ck_pr_fence_strict_atomic(void);

DESCRIPTION

The ck_pr_fence_atomic() function enforces the ordering of any atomic read-modify-write operations relative to the invocation of the function. 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. On architectures implementing CK_MD_PSO and CK_MD_RMO, a store fence is emitted. To force the unconditional emission of a fence, use ck_pr_fence_strict_atomic().

EXAMPLE

#include <ck_pr.h>

static int a = 0;
static int b = 0;
static int c = 0;

void
function(void)
{

	ck_pr_fas_int(&a, 1);

	/*
	 * Guarantee that the update to a is completed
	 * with respect to the updates of b and c.
	 */
	ck_pr_fence_atomic();
	ck_pr_fas_int(&b, 2);
	ck_pr_fas_int(&c, 2);

	return;
}

RETURN VALUES

This function has no return value.

SEE ALSO

ck_pr_stall(3), ck_pr_fence_atomic_store(3), ck_pr_fence_atomic_load(3), ck_pr_fence_store(3), ck_pr_fence_load(3), ck_pr_fence_load_atomic(3), ck_pr_fence_load_store(3), ck_pr_fence_load_depends(3), ck_pr_fence_memory(3), ck_pr_barrier(3), ck_pr_fas(3), ck_pr_load(3), ck_pr_store(3), ck_pr_faa(3), ck_pr_inc(3), ck_pr_dec(3), ck_pr_neg(3), ck_pr_not(3), ck_pr_add(3), ck_pr_sub(3), ck_pr_and(3), ck_pr_or(3), ck_pr_xor(3), ck_pr_cas(3), ck_pr_btc(3), ck_pr_bts(3), ck_pr_btr(3)

Additional information available at http://concurrencykit.org/