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ck_pr_fence_load(3) Library Functions Manual ck_pr_fence_load(3)

NAME

ck_pr_fence_load —
enforce partial ordering of load operations

LIBRARY

Concurrency Kit (libck, -lck)

SYNOPSIS

#include <ck_pr.h>
void
ck_pr_fence_load(void);
void
ck_pr_fence_strict_load(void);

DESCRIPTION

This function enforces the ordering of any memory load and ck_pr_load(3) operations relative to the invocation of the function. Any store operations that were committed on remote processors and received by the calling processor before the invocation of ck_pr_fence_load() is also be made visible only after a call to ck_pr_fence_load(). This function always serves as an implicit compiler barrier. On architectures with CK_MD_TSO or CK_MD_PSO specified (total store ordering and partial store ordering respectively), this operation only serves as a compiler barrier and no fence instructions will be emitted. To force the unconditional emission of a load fence, use ck_pr_fence_strict_load(). Architectures implementing CK_MD_RMO always emit a load fence.

EXAMPLE


#include <ck_pr.h> 
 
static unsigned int a; 
static unsigned int b; 
 
void 
function(void) 
{ 
	unsigned int snapshot_a, snapshot_b; 
 
	snapshot_a = ck_pr_load_uint(&a); 
 
	/* 
	 * Guarantee that the load from "a" completes 
	 * before the load from "b". 
	 */ 
	ck_pr_fence_load(); 
	snapshot_b = ck_pr_load_uint(&b); 
 
	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_atomic(3), ck_pr_fence_load_store(3), ck_pr_fence_load_depends(3), ck_pr_fence_store(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/
April 7, 2013