NAME¶

ck_pr_fence_memory — enforce partial ordering of all memory operations

LIBRARY¶

Concurrency Kit (libck, -lck)

SYNOPSIS¶

#include <ck_pr.h>

void
ck_pr_fence_memory();

void
ck_pr_fence_strict_memory();

DESCRIPTION¶

The 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 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.

SEE ALSO¶

ck_pr_stall(3), ck_pr_fence_atomic(3), ck_pr_fence_atomic_store(3), ck_pr_fence_atomic_load(3), ck_pr_fence_load(3), ck_pr_fence_load_depends(3), ck_pr_fence_store(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/