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33 lines
564 B
33 lines
564 B
C MP+unlocklockonceonce+fencermbonceonce |
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(* |
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* Result: Never |
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* |
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* If two locked critical sections execute on the same CPU, stores in the |
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* first must propagate to each CPU before stores in the second do, even if |
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* the critical sections are protected by different locks. |
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*) |
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{} |
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P0(spinlock_t *s, spinlock_t *t, int *x, int *y) |
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{ |
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spin_lock(s); |
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WRITE_ONCE(*x, 1); |
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spin_unlock(s); |
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spin_lock(t); |
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WRITE_ONCE(*y, 1); |
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spin_unlock(t); |
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} |
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P1(int *x, int *y) |
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{ |
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int r1; |
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int r2; |
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r1 = READ_ONCE(*y); |
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smp_rmb(); |
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r2 = READ_ONCE(*x); |
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} |
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exists (1:r1=1 /\ 1:r2=0)
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