pid_max hang again...

[Paul Larson <plars@linuxtestproject.org>]

In the nightly bk pull testing I do, I saw that this got commited
yesterday:

-ChangeSet@1.619, 2002-09-05 08:45:49-07:00, mingo@elte.hu
-  [PATCH] pid-max-2.5.33-A0
-  
-  This is the pid-max patch, the one i sent for 2.5.31 was botched.  I
-  have removed the 'once' debugging stupidity - now PIDs start at 0
-  again.
-  Also, for an unknown reason the previous patch missed the hunk that 
-  had the declaration of 'DEFAULT_PID_MAX' which made it not compile

It looks like this change dropped us back to the same error all this was
originally supposed to fix.  When you hit PID_MAX, get_pid() starts
looping forever looking for a free pid and hangs.  I could probably make
my original fix work on this very easily if you'd like.

I wonder though, would it be possible to do this in a more simple way by
just throttling max_threads back to something more sane if it gets
defaulted too high?  Since it gets checked before we even get to the
get_pid call in copy_process().  That would keep the number of processes
down to a sane level without the risk.

Thanks,
Paul Larson
http://www.linuxtestproject.org