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37 lines
704 B
37 lines
704 B
C RCU+sync+read |
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(* |
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* Result: Never |
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* |
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* This litmus test demonstrates that after a grace period, an RCU updater always |
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* sees all stores done in prior RCU read-side critical sections. Such |
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* read-side critical sections would have ended before the grace period ended. |
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* |
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* This is one implication of the RCU grace-period guarantee, which says (among |
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* other things) that an RCU read-side critical section cannot span a grace period. |
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*) |
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{ |
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int x = 0; |
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int y = 0; |
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} |
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P0(int *x, int *y) |
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{ |
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rcu_read_lock(); |
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WRITE_ONCE(*x, 1); |
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WRITE_ONCE(*y, 1); |
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rcu_read_unlock(); |
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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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synchronize_rcu(); |
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r1 = READ_ONCE(*y); |
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} |
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exists (1:r0=1 /\ 1:r1=0)
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