This PR adds an extra guarantee to NodeStateMachine: it ensures that all
immediate effects of a certain change are processed before any subsequent
effects of any of the immediate effects on the same node. In the original
version, if a cascaded change caused a subscription callback to be called
multiple times for the same node then these calls might have happened in a
wrong chronological order.
For example:
- a subscription to flag0 changes flag1 and flag2
- a subscription to flag1 changes flag3
- a subscription to flag1, flag2 and flag3 was called in the following order:
[flag1] -> [flag1, flag3]
[] -> [flag1]
[flag1, flag3] -> [flag1, flag2, flag3]
This happened because the tree of changes was traversed in a "depth-first
order". Now it is traversed in a "breadth-first order"; each node has a
FIFO queue for pending callbacks and each triggered subscription callback
is added to the end of the list. The already existing guarantees are
retained; no SetState or SetField returns until the callback queue of the
node is empty again. Just like before, it is the responsibility of the
state machine design to ensure that infinite state loops are not possible.
Multiple changes affecting the same node can still happen simultaneously;
in this case the changes can be interleaved in the FIFO of the node but the
correct order is still guaranteed.
A new unit test is also added to verify callback order in the above scenario.
# Conflicts:
# les/serverpool.go
# p2p/nodestate/nodestate.go
# p2p/nodestate/nodestate_test.go
This PR changes several different things:
- Adds test cases for the miner loop
- Stops the worker if it wasn't already stopped in worker.Close()
- Uses channels instead of atomics in the miner.update() loop
Co-authored-by: Felix Lange <fjl@twurst.com>
# Conflicts:
# miner/miner.go
* core/rawdb: Stop freezer process as part of freezer.Close()
When you call db.Close(), it was closing the leveldb database first,
then closing the freezer, but never stopping the freezer process.
This could cause the freezer to attempt to write to leveldb after
leveldb had been closed, leading to a crash with a non-zero exit code.
This change adds a quit channel to the freezer, and freezer.Close()
will not return until the freezer process has stopped.
Additionally, when you call freezerdb.Close(), it will close the
AncientStore before closing leveldb, to ensure that the freezer goroutine
will be stopped before leveldb is closed.
* core/rawdb: Fix formatting for golint
* core/rawdb: Use backoff flag to avoid repeating select
* core/rawdb: Include accidentally omitted backoff
# Conflicts:
# core/rawdb/database.go
# core/rawdb/freezer.go
This finally adds the error check that the documentation of StateDB.dbErr
promises to do. dbErr was added in 9e5f03b6c (June 2017), and the check was
already missing in that commit. We somehow survived without it for three years.
# Conflicts:
# core/state/statedb.go
# core/state/statedb_test.go
* Include 0x0000 address into the dump if it is present
* core/state: go fmt
Co-authored-by: Alexey Akhunov <akhounov@gmail.com>
# Conflicts:
# core/state/dump.go
