Re: LW_SHARED_MASK macro

On Thu, Sep 17, 2015 at 5:38 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:

> On 2015-09-17 14:35:20 +0300, Alexander Korotkov wrote:
> > while exploring lwlock.c I found following macro to be strange.
> >
> > #define LW_SHARED_MASK ((uint32)(1 << 23))
> >
> > This is macro is used to extract number of shared locks from state.
> >
> > ereport(LOG,
> > (errhidestmt(true),
> > errhidecontext(true),
> > errmsg("%d: %s(%s): excl %u shared %u haswaiters %u waiters %u rOK %d",
> > MyProcPid,
> > where, MainLWLockNames[id],
> > !!(state & LW_VAL_EXCLUSIVE),
> > state & LW_SHARED_MASK,
> > !!(state & LW_FLAG_HAS_WAITERS),
> > pg_atomic_read_u32(&lock->nwaiters),
> > !!(state & LW_FLAG_RELEASE_OK))));
> >
> >
> > Should it be ((uint32) ((1 << 24)-1)) instead?
>
> Argh, that's somewhat embarassing. You're absolutely right. Luckily it's
> only used for LOCK_DEBUG, but still...
>

Great. BTW, are you going to commit this?

------
Alexander Korotkov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company