mirror of https://gitee.com/openkylin/linux.git
39 lines
644 B
Plaintext
39 lines
644 B
Plaintext
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C WRC+pooncerelease+fencermbonceonce+Once
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(*
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* Result: Never
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*
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* This litmus test is an extension of the message-passing pattern, where
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* the first write is moved to a separate process. Because it features
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* a release and a read memory barrier, it should be forbidden. More
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* specifically, this litmus test is forbidden because smp_store_release()
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* is A-cumulative in LKMM.
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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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r0 = READ_ONCE(*x);
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smp_store_release(y, 1);
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}
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P2(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_rmb();
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r1 = READ_ONCE(*x);
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}
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exists (1:r0=1 /\ 2:r0=1 /\ 2:r1=0)
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