The previous wrong value lead to wrong LOCK_DEBUG output, never showing
any shared lock holders.
Reported-By: Alexander Korotkov
Discussion: CAPpHfdsPmWqz9FB0AnxJrwp1=KLF0n=-iB+QvR0Q8GSmpFVdUQ@mail.gmail.com
Backpatch: 9.5, where the bug was introduced.
#define LW_LOCK_MASK ((uint32) ((1 << 25)-1))
/* Must be greater than MAX_BACKENDS - which is 2^23-1, so we're fine. */
-#define LW_SHARED_MASK ((uint32)(1 << 23))
+#define LW_SHARED_MASK ((uint32) ((1 << 24)-1))
/*
* This is indexed by tranche ID and stores metadata for all tranches known