[PATCH] Enable tdb mutex support in CTDB

[Stefan (metze) Metzmacher]

Hi Amitay,

> Here are the patches to enable tdb mutex support in ctdb.  It's possible to
> enable the mutex support per node basis.
> 
> Volker, I have modified your original patch to support building with older
> version of tdb without mutex support (using configure check variable
> USE_TDB_MUTEX_LOCKING).  Please sign-off if you are ok with it.

You need to use tdb_runtime_check_for_robust_mutexes() before using
TDB_MUTEX_LOCKING. Otherwise tdb_open_ex will fail instead of
ignoring TDB_MUTEX_LOCKING (as the early development version did).

You should use that instead of #ifdef USE_TDB_MUTEX_LOCKING

Mutex support is a runtime decision not a configure time decision any more.

Please test with and without '--disable-tdb-mutex-locking'.

metze