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resources: fix deadlock on recursion

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This was a sneaky deadlock which wasn't 100% reproducible. It was pretty
tricky to find because the same deadlocked behaviour was seen due to the
regression in the fsnotify module.

The event system needs a bit of a cleaning, but this can happen later.
This commit is contained in:
James Shubin
2016-10-01 08:19:46 -04:00
parent 9368c7e05f
commit 567dcaf79d
1 changed files with 18 additions and 16 deletions
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34
resources/resources.go
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@@ -242,22 +242,24 @@ func (obj *BaseRes) SetState(state ResState) {
func (obj *BaseRes) DoSend(processChan chan event.Event, comment string) (bool, error) {
resp := event.NewResp()
processChan <- event.Event{event.EventNil, resp, comment, true} // trigger process
select {
case e := <-resp: // wait for the ACK()
if e != nil { // we got a NACK
return true, e // exit with error
}
case event := <-obj.events:
// NOTE: this code should match the similar code below!
//cuuid.SetConverged(false) // TODO ?
if exit, send := obj.ReadEvent(&event); exit {
return true, nil // exit, without error
} else if send {
return obj.DoSend(processChan, comment) // recurse
}
}
return false, nil // return, no error or exit signal
e := resp.Wait()
return false, e // XXX: at the moment, we don't use the exit bool.
// XXX: this can cause a deadlock. do we need to recursively send? fix event stuff!
//select {
//case e := <-resp: // wait for the ACK()
// if e != nil { // we got a NACK
// return true, e // exit with error
// }
//case event := <-obj.events:
// // NOTE: this code should match the similar code below!
// //cuuid.SetConverged(false) // TODO ?
// if exit, send := obj.ReadEvent(&event); exit {
// return true, nil // exit, without error
// } else if send {
// return obj.DoSend(processChan, comment) // recurse
// }
//}
//return false, nil // return, no error or exit signal
}
// SendEvent pushes an event into the message queue for a particular vertex