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 |