Re: global barrier & atomics in signal handlers (Re: Atomic operations within spinlocks)

On Wed, Jun 17, 2020 at 2:33 PM Andres Freund <andres(at)anarazel(dot)de> wrote:
> > It seems odd and confusing that we have both
> > S_LOCK() and s_lock(), anyway. Differentiating functions based on case
> > is not great practice.
>
> It's a terrible idea, yes. Since we don't actually have any non-default
> implementations of S_LOCK, perhaps we should just rip it out?

I think we should rip out the conditional nature of the definition and
fix the comments. I don't think I prefer getting rid of it completely.

But then again on the other hand, what's the point of this crap anyway:

#define SpinLockInit(lock) S_INIT_LOCK(lock)
#define SpinLockAcquire(lock) S_LOCK(lock)
#define SpinLockRelease(lock) S_UNLOCK(lock)
#define SpinLockFree(lock) S_LOCK_FREE(lock)

This seems like it's straight out of the department of pointless
abstraction layers. Maybe we should remove all of the S_WHATEVER()
stuff and just define SpinLockAcquire() where we currently define
S_LOCK(), SpinLockRelease() where we currently define S_UNLOCK(), etc.

And, as you say, make them static inline functions while we're at it.

--
Robert Haas
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