Re: LW_SHARED_MASK macro - Mailing list pgsql-hackers

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...