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2ba5b4130e
The four litmus tests in Documentation/litmus-tests/atomic do not declare all of their local variables. Although this is just fine for LKMM analysis by herd7, it causes build failures when run in-kernel by klitmus. This commit therefore adjusts these tests to declare all local variables. Reported-by: Andrea Parri <parri.andrea@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Andrea Parri <parri.andrea@gmail.com>
30 lines
392 B
Text
30 lines
392 B
Text
C cmpxchg-fail-ordered-2
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(*
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* Result: Never
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*
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* Demonstrate use of smp_mb__after_atomic() to make a failing cmpxchg
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* operation have acquire ordering.
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*)
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{}
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P0(int *x, int *y)
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{
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int r1;
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WRITE_ONCE(*x, 1);
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r1 = cmpxchg(y, 0, 1);
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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 = cmpxchg(y, 0, 1);
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smp_mb__after_atomic();
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r2 = READ_ONCE(*x);
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}
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exists (0:r1=0 /\ 1:r1=1 /\ 1:r2=0)
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