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33 lines
593 B
33 lines
593 B
C MP+onceassign+derefonce |
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(* |
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* Result: Never |
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* |
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* This litmus test demonstrates that rcu_assign_pointer() and |
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* rcu_dereference() suffice to ensure that an RCU reader will not see |
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* pre-initialization garbage when it traverses an RCU-protected data |
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* structure containing a newly inserted element. |
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*) |
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{ |
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p=y; |
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} |
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P0(int *x, int **p) // Producer |
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{ |
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WRITE_ONCE(*x, 1); |
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rcu_assign_pointer(*p, x); |
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} |
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P1(int *x, int **p) // Consumer |
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{ |
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int *r0; |
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int r1; |
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rcu_read_lock(); |
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r0 = rcu_dereference(*p); |
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r1 = READ_ONCE(*r0); |
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rcu_read_unlock(); |
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} |
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exists (1:r0=x /\ 1:r1=0) (* Bad outcome. *)
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