Re: Assertion failure in SnapBuildInitialSnapshot() - Mailing list pgsql-hackers

On Tue, Jan 31, 2023 at 6:08 PM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>
> Attached updated patches.
>

In back-branch patches, the change is as below:
+ *
+ * NB: the caller must hold ProcArrayLock in an exclusive mode regardless of
+ * already_locked which is unused now but kept for ABI compatibility.
  */
 void
 ProcArraySetReplicationSlotXmin(TransactionId xmin, TransactionId catalog_xmin,
  bool already_locked)
 {
- Assert(!already_locked || LWLockHeldByMe(ProcArrayLock));
-
- if (!already_locked)
- LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
+ Assert(LWLockHeldByMeInMode(ProcArrayLock, LW_EXCLUSIVE));

This change looks odd to me. I think it would be better to pass
'already_locked' as true from the caller.

-- 
With Regards,
Amit Kapila.