mirror of https://gitee.com/openkylin/linux.git
33 lines
499 B
Plaintext
33 lines
499 B
Plaintext
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C SB+fencembonceonces
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(*
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* Result: Never
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*
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* This litmus test demonstrates that full memory barriers suffice to
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* order the store-buffering pattern, where each process writes to the
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* variable that the preceding process reads. (Locking and RCU can also
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* suffice, but not much else.)
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*)
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{}
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P0(int *x, int *y)
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{
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int r0;
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WRITE_ONCE(*x, 1);
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smp_mb();
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r0 = READ_ONCE(*y);
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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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WRITE_ONCE(*y, 1);
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smp_mb();
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r0 = READ_ONCE(*x);
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}
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exists (0:r0=0 /\ 1:r0=0)
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