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