During problems with zk connectivity jobs can fail locking nodes
[1]. In this case the build doesn't get created and attached to the
queue item. However semaphores are already aquired at this point and
don't get released in this case. Fix this by releasing the semaphore
when hitting this exception.
[1] Trace:
2018-04-05 10:56:56,936 ERROR zuul.Pipeline.example.check: Exception while executing job example-test for change <Change 0x7f65e9dd59e8 14,55692b4a936fff57e33036399927332849a53a92>:
Traceback (most recent call last):
File "/usr/lib/python3.6/site-packages/zuul/manager/__init__.py", line 396, in _executeJobs
self.sched.nodepool.useNodeSet(nodeset)
File "/usr/lib/python3.6/site-packages/zuul/nodepool.py", line 117, in useNodeSet
self.sched.zk.storeNode(node)
File "/usr/lib/python3.6/site-packages/zuul/zk.py", line 213, in storeNode
self.client.set(path, self._dictToStr(node.toDict()))
File "/usr/lib/python3.6/site-packages/kazoo/client.py", line 1242, in set
return self.set_async(path, value, version).get()
File "/usr/lib/python3.6/site-packages/kazoo/handlers/utils.py", line 79, in get
raise self._exception
kazoo.exceptions.NoNodeError
Change-Id: I851876ece318aa047e523c50f4c721417d1af6b7
Tobias Henkel