go-ethereum/swarm/network/simulation
Ferenc Szabo 50b872bf05 p2p, swarm: fix node up races by granular locking (#18976)
* swarm/network: DRY out repeated giga comment

I not necessarily agree with the way we wait for event propagation.
But I truly disagree with having duplicated giga comments.

* p2p/simulations: encapsulate Node.Up field so we avoid data races

The Node.Up field was accessed concurrently without "proper" locking.
There was a lock on Network and that was used sometimes to access
the  field. Other times the locking was missed and we had
a data race.

For example: https://github.com/ethereum/go-ethereum/pull/18464
The case above was solved, but there were still intermittent/hard to
reproduce races. So let's solve the issue permanently.

resolves: ethersphere/go-ethereum#1146

* p2p/simulations: fix unmarshal of simulations.Node

Making Node.Up field private in 13292ee897
broke TestHTTPNetwork and TestHTTPSnapshot. Because the default
UnmarshalJSON does not handle unexported fields.

Important: The fix is partial and not proper to my taste. But I cut
scope as I think the fix may require a change to the current
serialization format. New ticket:
https://github.com/ethersphere/go-ethereum/issues/1177

* p2p/simulations: Add a sanity test case for Node.Config UnmarshalJSON

* p2p/simulations: revert back to defer Unlock() pattern for Network

It's a good patten to call `defer Unlock()` right after `Lock()` so
(new) error cases won't miss to unlock. Let's get back to that pattern.

The patten was abandoned in 85a79b3ad3,
while fixing a data race. That data race does not exist anymore,
since the Node.Up field got hidden behind its own lock.

* p2p/simulations: consistent naming for test providers Node.UnmarshalJSON

* p2p/simulations: remove JSON annotation from private fields of Node

As unexported fields are not serialized.

* p2p/simulations: fix deadlock in Network.GetRandomDownNode()

Problem: GetRandomDownNode() locks -> getDownNodeIDs() ->
GetNodes() tries to lock -> deadlock

On Network type, unexported functions must assume that `net.lock`
is already acquired and should not call exported functions which
might try to lock again.

* p2p/simulations: ensure method conformity for Network

Connect* methods were moved to p2p/simulations.Network from
swarm/network/simulation. However these new methods did not follow
the pattern of Network methods, i.e., all exported method locks
the whole Network either for read or write.

* p2p/simulations: fix deadlock during network shutdown

`TestDiscoveryPersistenceSimulationSimAdapter` often got into deadlock.
The execution was stuck on two locks, i.e, `Kademlia.lock` and
`p2p/simulations.Network.lock`. Usually the test got stuck once in each
20 executions with high confidence.

`Kademlia` was stuck in `Kademlia.EachAddr()` and `Network` in
`Network.Stop()`.

Solution: in `Network.Stop()` `net.lock` must be released before
calling `node.Stop()` as stopping a node (somehow - I did not find
the exact code path) causes `Network.InitConn()` to be called from
`Kademlia.SuggestPeer()` and that blocks on `net.lock`.

Related ticket: https://github.com/ethersphere/go-ethereum/issues/1223

* swarm/state: simplify if statement in DBStore.Put()

* p2p/simulations: remove faulty godoc from private function

The comment started with the wrong method name.

The method is simple and self explanatory. Also, it's private.
=> Let's just remove the comment.
2019-02-18 07:38:14 +01:00
..
bucket.go A few minor code inspection fixes (#18393) 2019-01-06 11:58:57 +01:00
bucket_test.go A few minor code inspection fixes (#18393) 2019-01-06 11:58:57 +01:00
events.go swarm/network/simulation: use simulations.Event instead p2p.PeerEvent (#18098) 2018-11-15 21:06:27 +01:00
events_test.go swarm: Fix T.Fatal inside a goroutine in tests (#18409) 2019-01-09 07:05:55 +01:00
example_test.go swarm/network: Rename minproxbinsize, add as member of simulation (#18408) 2019-01-10 12:33:51 +01:00
http.go Merge netsim mig to master (#17241) 2018-07-30 22:55:25 +02:00
http_test.go swarm: Fix T.Fatal inside a goroutine in tests (#18409) 2019-01-09 07:05:55 +01:00
kademlia.go swarm/network: Saturation check for healthy networks (#19071) 2019-02-14 19:01:50 +01:00
kademlia_test.go swarm/network: unskip tests previously skipped due to suggestPeer issues (#18477) 2019-01-19 08:12:57 +01:00
node.go p2p, swarm: fix node up races by granular locking (#18976) 2019-02-18 07:38:14 +01:00
node_test.go p2p, swarm: fix node up races by granular locking (#18976) 2019-02-18 07:38:14 +01:00
service.go p2p, swarm: fix node up races by granular locking (#18976) 2019-02-18 07:38:14 +01:00
service_test.go swarm: network simulation for swarm tests (#769) 2018-07-23 15:33:25 +02:00
simulation.go p2p/simulations: eliminate concept of pivot (#18426) 2019-01-11 10:23:45 +01:00
simulation_test.go p2p, swarm: fix node up races by granular locking (#18976) 2019-02-18 07:38:14 +01:00