test: adds outbound eviction functional tests, updates comment in ConsiderEviction

1 files changed, 7 insertions, 4 deletions

diff --git a/src/net_processing.cpp b/src/net_processing.cpp
index 39ffff97d2..f936f1b666 100644
--- a/src/net_processing.cpp
+++ b/src/net_processing.cpp
@@ -5165,16 +5165,19 @@ void PeerManagerImpl::ConsiderEviction(CNode& pto, Peer& peer, std::chrono::seco
         // unless it's invalid, in which case we should find that out and
         // disconnect from them elsewhere).
         if (state.pindexBestKnownBlock != nullptr && state.pindexBestKnownBlock->nChainWork >= m_chainman.ActiveChain().Tip()->nChainWork) {
+            // The outbound peer has sent us a block with at least as much work as our current tip, so reset the timeout if it was set
             if (state.m_chain_sync.m_timeout != 0s) {
                 state.m_chain_sync.m_timeout = 0s;
                 state.m_chain_sync.m_work_header = nullptr;
                 state.m_chain_sync.m_sent_getheaders = false;
             }
         } else if (state.m_chain_sync.m_timeout == 0s || (state.m_chain_sync.m_work_header != nullptr && state.pindexBestKnownBlock != nullptr && state.pindexBestKnownBlock->nChainWork >= state.m_chain_sync.m_work_header->nChainWork)) {
-            // Our best block known by this peer is behind our tip, and we're either noticing
-            // that for the first time, OR this peer was able to catch up to some earlier point
-            // where we checked against our tip.
-            // Either way, set a new timeout based on current tip.
+            // At this point we know that the outbound peer has either never sent us a block/header or they have, but its tip is behind ours
+            // AND
+            // we are noticing this for the first time (m_timeout is 0)
+            // OR we noticed this at some point within the last CHAIN_SYNC_TIMEOUT + HEADERS_RESPONSE_TIME seconds and set a timeout
+            // for them, they caught up to our tip at the time of setting the timer but not to our current one (we've also advanced).
+            // Either way, set a new timeout based on our current tip.
             state.m_chain_sync.m_timeout = time_in_seconds + CHAIN_SYNC_TIMEOUT;
             state.m_chain_sync.m_work_header = m_chainman.ActiveChain().Tip();
             state.m_chain_sync.m_sent_getheaders = false;