Bug 918944

Description of problem:
When the following command is run at some point there will be a dead lock in setlkw calls at the bricks because of order of arrival.

execute the following command.
while tests/bugs/bug-905864.t; do :; done
after an hour or so the test hangs and when we observe the statedump we see that in two stripe subolumes the order of arrival of setlkws is swapped which causes a dead lock.

On brick-5 here are the locks:
[xlator.features.locks.patchy-locks.inode]
path=/file1
mandatory=0
posixlk-count=2
posixlk.posixlk[0](ACTIVE)=type=WRITE, whence=0, start=0, len=2, pid = 32312, owner=c753d2d946fd5b45, transport=0x150cf30, , granted at Thu Mar  7 14:03:57 2013

posixlk.posixlk[1](BLOCKED)=type=WRITE, whence=0, start=0, len=2, pid = 32309, owner=9a4f25833ec8c200, transport=0x150d5b0, , blocked at Thu Mar  7 14:03:57 2013

On brick7 these are the locks:
[xlator.features.locks.patchy-locks.inode]
path=/file1
mandatory=0
posixlk-count=2
posixlk.posixlk[0](ACTIVE)=type=WRITE, whence=0, start=0, len=2, pid = 32309, owner=9a4f25833ec8c200, transport=0xe82b90, , granted at Thu Mar  7 14:03:57 2013

posixlk.posixlk[1](BLOCKED)=type=WRITE, whence=0, start=0, len=2, pid = 32312, owner=c753d2d946fd5b45, transport=0xe84480, , blocked at Thu Mar  7 14:03:57 2013

As we can see this causes a dead lock.

Version-Release number of selected component (if applicable):


How reproducible:
1/1

Steps to Reproduce:
1.As per the description
2.
3.
  
Actual results:
Tests hung

Expected results:
Tests should not hang.

Additional info: