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CK_PR_FENCE_LOAD_AT... FreeBSD Library Functions Manual	CK_PR_FENCE_LOAD_AT...

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 re-
     spectively), 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 im-
     plementing	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

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

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