1CK_PR_FENCE_LOAD_STOR... BSD Library Functions Manual CK_PR_FENCE_LOAD_STOR...
2

NAME

4     ck_pr_fence_load_store — enforce ordering of load operations to store
5     operations
6

LIBRARY

8     Concurrency Kit (libck, -lck)
9

SYNOPSIS

11     #include <ck_pr.h>
12
13     void
14     ck_pr_fence_load_store(void);
15
16     void
17     ck_pr_fence_strict_load_store(void);
18

DESCRIPTION

20     This function enforces the ordering of any memory load and ck_pr_load(3)
21     operations with respect to store operations relative to the invocation of
22     the function. Any store operations that were committed on remote proces‐
23     sors and received by the calling processor before the invocation of
24     ck_pr_fence_load_store() is also be made visible only after a call to the
25     ck_pr_fence_load family of functions.  This function always serves as an
26     implicit compiler barrier.  On architectures with CK_MD_TSO or CK_MD_PSO
27     specified (total store ordering and partial store ordering respectively),
28     this operation only serves as a compiler barrier and no fence instruc‐
29     tions will be emitted. To force the unconditional emission of a load
30     fence, use ck_pr_fence_strict_load_store().  Architectures implementing
31     CK_MD_RMO always emit a fence.
32

EXAMPLE

34           #include <ck_pr.h>
35
36           static unsigned int a;
37           static unsigned int b;
38
39           void
40           function(void)
41           {
42                   unsigned int snapshot_a;
43
44                   snapshot_a = ck_pr_load_uint(&a);
45
46                   /*
47                    * Guarantee that the load from "a" completes
48                    * before the store to "b".
49                    */
50                   ck_pr_fence_load_store();
51                   ck_pr_store_uint(&b, 1);
52
53                   return;
54           }
55

RETURN VALUES

57     This function has no return value.
58

SEE ALSO

60     ck_pr_stall(3), ck_pr_fence_atomic(3), ck_pr_fence_atomic_store(3),
61     ck_pr_fence_atomic_load(3), ck_pr_fence_load_depends(3),
62     ck_pr_fence_load_atomic(3), ck_pr_fence_store(3), ck_pr_fence_memory(3),
63     ck_pr_barrier(3), ck_pr_fas(3), ck_pr_load(3), ck_pr_store(3),
64     ck_pr_faa(3), ck_pr_inc(3), ck_pr_dec(3), ck_pr_neg(3), ck_pr_not(3),
65     ck_pr_add(3), ck_pr_sub(3), ck_pr_and(3), ck_pr_or(3), ck_pr_xor(3),
66     ck_pr_cas(3), ck_pr_btc(3), ck_pr_bts(3), ck_pr_btr(3)
67
68     Additional information available at http://concurrencykit.org/
69
70                                 May 18, 2013
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