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                              ck_pr_fence_load(3)