OK to set PF_MEMDIE on cleanup tasks?

["Paul E. McKenney" <paulmck@us.ibm.com>]

Hello!

We have tasks that actively return memory to the system, which we
would like to exempt from the OOM killer, as killing such tasks under
low-memory conditions would indeed be counterproductive.  It looks like
the "official" way to do this is to catch/ignore signal 15, which results
in PF_MEMDIE being set (in the 2.6 kernel), thus preventing the OOM killer
from killing the task again.  I don't see where PF_MEMDIE is cleared,
though there are a number of subtle ways one might do this that I would
have missed.

So...  Is it considered legit to simply set PF_MEMDIE when creating
the cleanup task?  Or is there some reason that one should deal with
signal 15?

All enlightenment much appreciated!

						Thanx, Paul