38 lines
704 B
Plaintext
38 lines
704 B
Plaintext
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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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