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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 re-
       ceived  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  com-
       piler  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)

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