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CK_PR_FENCE_LOAD_ATOM... BSD Library Functions Manual CK_PR_FENCE_LOAD_ATOM...

NAME
     ck_pr_fence_load_atomic -- enforce ordering of load operations to atomic
     read-modify-write operations

LIBRARY
     Concurrency Kit (libck, -lck)

SYNOPSIS
     #include <ck_pr.h>

     void
     ck_pr_fence_load_atomic(void);

     void
     ck_pr_fence_strict_load_atomic(void);

DESCRIPTION
     This function enforces the ordering of any memory load and ck_pr_load(3)
     operations with respect to store operations relative to the invocation of
     the function. Any store operations that were committed on remote proces-
     sors and received by the calling processor before the invocation of
     ck_pr_fence_load_atomic() is also be made visible only after a call to
     the ck_pr_fence_load family of functions.  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_atomic().  Architectures
     implementing CK_MD_RMO always emit a 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 update to "b".
                    */
                   ck_pr_fence_load_atomic();
                   ck_pr_fas_uint(&b, 1);

                   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_depends(3),
     ck_pr_fence_load_store(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/

                                 May 18, 2013