46 lines
731 B
Plaintext
46 lines
731 B
Plaintext
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C IRIW+fencembonceonces+OnceOnce
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(*
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* Result: Never
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*
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* Test of independent reads from independent writes with smp_mb()
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* between each pairs of reads. In other words, is smp_mb() sufficient to
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* cause two different reading processes to agree on the order of a pair
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* of writes, where each write is to a different variable by a different
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* process? This litmus test exercises LKMM's "propagation" rule.
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*)
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{}
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P0(int *x)
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{
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WRITE_ONCE(*x, 1);
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}
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P1(int *x, int *y)
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{
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int r0;
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int r1;
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r0 = READ_ONCE(*x);
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smp_mb();
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r1 = READ_ONCE(*y);
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}
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P2(int *y)
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{
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WRITE_ONCE(*y, 1);
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}
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P3(int *x, int *y)
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{
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int r0;
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int r1;
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r0 = READ_ONCE(*y);
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smp_mb();
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r1 = READ_ONCE(*x);
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}
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exists (1:r0=1 /\ 1:r1=0 /\ 3:r0=1 /\ 3:r1=0)
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