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Diffstat (limited to 'tools/memory-model/litmus-tests/MP+polockmbonce+poacquiresilsil.litmus')
| -rw-r--r-- | tools/memory-model/litmus-tests/MP+polockmbonce+poacquiresilsil.litmus | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/tools/memory-model/litmus-tests/MP+polockmbonce+poacquiresilsil.litmus b/tools/memory-model/litmus-tests/MP+polockmbonce+poacquiresilsil.litmus new file mode 100644 index 0000000000..ba91cc63e1 --- /dev/null +++ b/tools/memory-model/litmus-tests/MP+polockmbonce+poacquiresilsil.litmus @@ -0,0 +1,34 @@ +C MP+polockmbonce+poacquiresilsil + +(* + * Result: Never + * + * Do spinlocks combined with smp_mb__after_spinlock() provide order + * to outside observers using spin_is_locked() to sense the lock-held + * state, ordered by acquire? Note that when the first spin_is_locked() + * returns false and the second true, we know that the smp_load_acquire() + * executed before the lock was acquired (loosely speaking). + *) + +{} + +P0(spinlock_t *lo, int *x) // Producer +{ + spin_lock(lo); + smp_mb__after_spinlock(); + WRITE_ONCE(*x, 1); + spin_unlock(lo); +} + +P1(spinlock_t *lo, int *x) // Consumer +{ + int r1; + int r2; + int r3; + + r1 = smp_load_acquire(x); + r2 = spin_is_locked(lo); + r3 = spin_is_locked(lo); +} + +exists (1:r1=1 /\ 1:r2=0 /\ 1:r3=1) (* Bad outcome. *) |