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

[Alan Stern]

On Fri, May 24, 2024 at 05:37:06PM +0200, Andrea Parri wrote:
> > - 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);
> }

No "exists" clause?  Maybe that's your problem.

Alan

> 
> $ 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