Minor fix in lwlock.c

The chance that num_held_lwlocks is beyond MAX_SIMUL_LWLOCKS is similar to
the chance that failed to grasp a spinlock in 1 minute, so they should be
treated in the same way. This is mainly to prevent programming error (e.g.,
forget to release the LWLocks).

Regards,
Qingqing

---

Index: lwlock.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/backend/storage/lmgr/lwlock.c,v
retrieving revision 1.25
diff -c -r1.25 lwlock.c
*** lwlock.c 31 Dec 2004 22:01:05 -0000 1.25
--- lwlock.c 8 Apr 2005 02:19:31 -0000
***************
*** 328,334 ****
SpinLockRelease_NoHoldoff(&lock->mutex);

/* Add lock to list of locks held by this backend */
! Assert(num_held_lwlocks < MAX_SIMUL_LWLOCKS);
held_lwlocks[num_held_lwlocks++] = lockid;

/*
--- 328,335 ----
SpinLockRelease_NoHoldoff(&lock->mutex);

/* Add lock to list of locks held by this backend */
! if (num_held_lwlocks >= MAX_SIMUL_LWLOCKS)
! elog(FATAL, "Too many LWLocks");
held_lwlocks[num_held_lwlocks++] = lockid;

/*
***************
*** 397,403 ****
else
{
/* Add lock to list of locks held by this backend */
! Assert(num_held_lwlocks < MAX_SIMUL_LWLOCKS);
held_lwlocks[num_held_lwlocks++] = lockid;
}

--- 398,405 ----
else
{
/* Add lock to list of locks held by this backend */
! if (num_held_lwlocks >= MAX_SIMUL_LWLOCKS)
! elog(FATAL, "Too many LWLocks");
held_lwlocks[num_held_lwlocks++] = lockid;
}