[net processing] Remove PushBlockInventory and PushBlockHash
PushBlockInventory() and PushBlockHash() are functions that can
be replaced with single-line statements. This also eliminates
the single place that cs_inventory is taken recursively.
[net] Make cs_inventory a non-recursive mutex
cs_inventory is never taken recursively. Make it a non-recursive mutex.
[net] Don't try to take cs_inventory before deleting CNode
The TRY_LOCK(cs_inventory) in DisconnectNodes() is taken after the CNode
object has been removed from vNodes and when the CNode's nRefCount is
The only other places that cs_inventory can be taken are:
- In ProcessMessages() or SendMessages(), when the CNode's nRefCount
must be >0 (see ThreadMessageHandler(), where the refcount is
incremented before calling ProcessMessages() and SendMessages()).
- In a ForEachNode() lambda in PeerLogicValidation::UpdatedBlockTip().
ForEachNode() locks cs_vNodes and calls the function on the CNode
objects in vNodes.
Therefore, cs_inventory is never locked by another thread when the
TRY_LOCK(cs_inventory) is reached in DisconnectNodes(). Since the
only purpose of this TRY_LOCK is to ensure that the lock is not
taken by another thread, this always succeeds. Remove the check.
This is a backport of core#19347