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5c587f9b9c
This is a revert of commit 1947bfcf81 ("tools/memory-model: Add types
to litmus tests") with conflict resolutions.
klitmus7 [1] is aware of default types of "int" and "int*".
It accepts litmus tests for herd7 without extra type info unless
non-"int" variables are referenced by an "exists", "locations",
or "filter" directive.
[1]: Tested with klitmus7 versions 7.49 or later.
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
34 lines
593 B
Plaintext
34 lines
593 B
Plaintext
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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