Re: [PATCH] tools/memory-model: Document herd7 (internal) representation

From: Andrea Parri
Date: Fri May 24 2024 - 11:38:06 EST


> - While checking the information below using herd7, I've observed some
> "strange" behavior with spin_is_locked() (perhaps, unsurprisingly...);
> IAC, that's also excluded from this table/submission.

For completeness, the behavior in question:

$ cat T.litmus
C T

{}

P0(spinlock_t *x)
{
int r0;

spin_lock(x);
spin_unlock(x);
r0 = spin_is_locked(x);
}

$ herd7 -conf linux-kernel.cfg T.litmus
Test T Required
States 0
Ok
Witnesses
Positive: 0 Negative: 0
Condition forall (true)
Observation T Never 0 0
Time T 0.00
Hash=6fa204e139ddddf2cb6fa963bad117c0

Haven't been using spin_is_locked for a while... perhaps I'm doing
something wrong? (IAC, will have a closer look next week...)

Andrea