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ck_pr_fence_load(3)    FreeBSD 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 opera-
     tions that	were committed on remote processors and	received by the	call-
     ing 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 implement-
     ing 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

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | EXAMPLE | RETURN VALUES | SEE ALSO

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