Skip to content

Commit d581b8d

Browse files
TheBlueMattTheBlueMatt
committed
DRY the pre-startup ChannelMonitorUpdate handling
This moves the common `if during_startup { push background event } else { apply ChannelMonitorUpdate }` pattern by simply inlining it in `handle_new_monitor_update`. It also ensures we always insert `ChannelMonitorUpdate`s in the pending updates set when we push the background event, avoiding a race where we push an update as a background event, then while its processing another update finishes and the post-update actions get run.
1 parent 995de2d commit d581b8d

File tree

1 file changed

+53
-75
lines changed

1 file changed

+53
-75
lines changed

‎lightning/src/ln/channelmanager.rs

+53-75
Original file line numberDiff line numberDiff line change
@@ -2954,31 +2954,9 @@ macro_rules! handle_error {
29542954
/// [`ChannelMonitor`]/channel funding transaction) to begin with.
29552955
macro_rules! locked_close_channel {
29562956
($self: ident, $peer_state: expr, $channel_context: expr, $shutdown_res_mut: expr) => {{
2957-
if let Some((counterparty_node_id, funding_txo, channel_id, update)) = $shutdown_res_mut.monitor_update.take() {
2958-
if $self.background_events_processed_since_startup.load(Ordering::Acquire) {
2959-
handle_new_monitor_update!($self, funding_txo, update, $peer_state,
2960-
$channel_context, REMAIN_LOCKED_UPDATE_ACTIONS_PROCESSED_LATER);
2961-
} else {
2962-
// We want to track the in-flight update both in `in_flight_monitor_updates` and in
2963-
// `pending_background_events` to avoid a race condition during
2964-
// `pending_background_events` processing where we complete one
2965-
// `ChannelMonitorUpdate` (but there are more pending as background events) but we
2966-
// conclude that all pending `ChannelMonitorUpdate`s have completed and its safe to
2967-
// run post-completion actions. We could work around that with some effort, but its
2968-
// simpler to just track updates twice.
2969-
let in_flight_updates = $peer_state.in_flight_monitor_updates.entry(funding_txo)
2970-
.or_insert_with(Vec::new);
2971-
if !in_flight_updates.contains(&update) {
2972-
in_flight_updates.push(update.clone());
2973-
}
2974-
let event = BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
2975-
counterparty_node_id,
2976-
funding_txo,
2977-
channel_id,
2978-
update,
2979-
};
2980-
$self.pending_background_events.lock().unwrap().push(event);
2981-
}
2957+
if let Some((_, funding_txo, _, update)) = $shutdown_res_mut.monitor_update.take() {
2958+
handle_new_monitor_update!($self, funding_txo, update, $peer_state,
2959+
$channel_context, REMAIN_LOCKED_UPDATE_ACTIONS_PROCESSED_LATER);
29822960
}
29832961
// If there's a possibility that we need to generate further monitor updates for this
29842962
// channel, we need to store the last update_id of it. However, we don't want to insert
@@ -3307,8 +3285,8 @@ macro_rules! handle_new_monitor_update {
33073285
};
33083286
(
33093287
$self: ident, $funding_txo: expr, $update: expr, $peer_state: expr, $logger: expr,
3310-
$chan_id: expr, $in_flight_updates: ident, $update_idx: ident, _internal_outer,
3311-
$completed: expr
3288+
$chan_id: expr, $counterparty_node_id: expr, $in_flight_updates: ident, $update_idx: ident,
3289+
_internal_outer, $completed: expr
33123290
) => { {
33133291
$in_flight_updates = $peer_state.in_flight_monitor_updates.entry($funding_txo)
33143292
.or_insert_with(Vec::new);
@@ -3320,31 +3298,55 @@ macro_rules! handle_new_monitor_update {
33203298
$in_flight_updates.push($update);
33213299
$in_flight_updates.len() - 1
33223300
});
3323-
let update_res = $self.chain_monitor.update_channel($funding_txo, &$in_flight_updates[$update_idx]);
3324-
handle_new_monitor_update!($self, update_res, $logger, $chan_id, _internal, $completed)
3301+
if $self.background_events_processed_since_startup.load(Ordering::Acquire) {
3302+
let update_res = $self.chain_monitor.update_channel($funding_txo, &$in_flight_updates[$update_idx]);
3303+
handle_new_monitor_update!($self, update_res, $logger, $chan_id, _internal, $completed)
3304+
} else {
3305+
// We blindly assume that the ChannelMonitorUpdate will be regenerated on startup if we
3306+
// fail to persist it. This is a fairly safe assumption, however, since anything we do
3307+
// during the startup sequence should be replayed exactly if we immediately crash.
3308+
let event = BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
3309+
counterparty_node_id: $counterparty_node_id,
3310+
funding_txo: $funding_txo,
3311+
channel_id: $chan_id,
3312+
update: $in_flight_updates[$update_idx].clone(),
3313+
};
3314+
// We want to track the in-flight update both in `in_flight_monitor_updates` and in
3315+
// `pending_background_events` to avoid a race condition during
3316+
// `pending_background_events` processing where we complete one
3317+
// `ChannelMonitorUpdate` (but there are more pending as background events) but we
3318+
// conclude that all pending `ChannelMonitorUpdate`s have completed and its safe to
3319+
// run post-completion actions.
3320+
// We could work around that with some effort, but its simpler to just track updates
3321+
// twice.
3322+
$self.pending_background_events.lock().unwrap().push(event);
3323+
false
3324+
}
33253325
} };
33263326
(
33273327
$self: ident, $funding_txo: expr, $update: expr, $peer_state: expr, $chan_context: expr,
33283328
REMAIN_LOCKED_UPDATE_ACTIONS_PROCESSED_LATER
33293329
) => { {
33303330
let logger = WithChannelContext::from(&$self.logger, &$chan_context, None);
33313331
let chan_id = $chan_context.channel_id();
3332+
let counterparty_node_id = $chan_context.get_counterparty_node_id();
33323333
let in_flight_updates;
33333334
let idx;
33343335
handle_new_monitor_update!($self, $funding_txo, $update, $peer_state, logger, chan_id,
3335-
in_flight_updates, idx, _internal_outer,
3336+
counterparty_node_id, in_flight_updates, idx, _internal_outer,
33363337
{
33373338
let _ = in_flight_updates.remove(idx);
33383339
})
33393340
} };
33403341
(
33413342
$self: ident, $funding_txo: expr, $update: expr, $peer_state_lock: expr, $peer_state: expr,
3342-
$per_peer_state_lock: expr, $logger: expr, $channel_id: expr, POST_CHANNEL_CLOSE
3343+
$per_peer_state_lock: expr, $counterparty_node_id: expr, $channel_id: expr, POST_CHANNEL_CLOSE
33433344
) => { {
3345+
let logger = WithContext::from(&$self.logger, Some($counterparty_node_id), Some($channel_id), None);
33443346
let in_flight_updates;
33453347
let idx;
3346-
handle_new_monitor_update!($self, $funding_txo, $update, $peer_state, $logger,
3347-
$channel_id, in_flight_updates, idx, _internal_outer,
3348+
handle_new_monitor_update!($self, $funding_txo, $update, $peer_state, logger,
3349+
$channel_id, $counterparty_node_id, in_flight_updates, idx, _internal_outer,
33483350
{
33493351
let _ = in_flight_updates.remove(idx);
33503352
if in_flight_updates.is_empty() {
@@ -3364,10 +3366,11 @@ macro_rules! handle_new_monitor_update {
33643366
) => { {
33653367
let logger = WithChannelContext::from(&$self.logger, &$chan.context, None);
33663368
let chan_id = $chan.context.channel_id();
3369+
let counterparty_node_id = $chan.context.get_counterparty_node_id();
33673370
let in_flight_updates;
33683371
let idx;
33693372
handle_new_monitor_update!($self, $funding_txo, $update, $peer_state, logger, chan_id,
3370-
in_flight_updates, idx, _internal_outer,
3373+
counterparty_node_id, in_flight_updates, idx, _internal_outer,
33713374
{
33723375
let _ = in_flight_updates.remove(idx);
33733376
if in_flight_updates.is_empty() && $chan.blocked_monitor_updates_pending() == 0 {
@@ -3997,11 +4000,10 @@ where
39974000
},
39984001
hash_map::Entry::Vacant(_) => {},
39994002
}
4000-
let logger = WithContext::from(&self.logger, Some(counterparty_node_id), Some(channel_id), None);
40014003

40024004
handle_new_monitor_update!(
40034005
self, funding_txo, monitor_update, peer_state_lock, peer_state, per_peer_state,
4004-
logger, channel_id, POST_CHANNEL_CLOSE
4006+
counterparty_node_id, channel_id, POST_CHANNEL_CLOSE
40054007
);
40064008
}
40074009

@@ -7188,7 +7190,6 @@ where
71887190
let peer_state = &mut **peer_state_lock;
71897191
if let hash_map::Entry::Occupied(mut chan_phase_entry) = peer_state.channel_by_id.entry(chan_id) {
71907192
if let ChannelPhase::Funded(chan) = chan_phase_entry.get_mut() {
7191-
let counterparty_node_id = chan.context.get_counterparty_node_id();
71927193
let logger = WithChannelContext::from(&self.logger, &chan.context, None);
71937194
let fulfill_res = chan.get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, payment_info, &&logger);
71947195

@@ -7203,21 +7204,8 @@ where
72037204
if let Some(raa_blocker) = raa_blocker_opt {
72047205
peer_state.actions_blocking_raa_monitor_updates.entry(chan_id).or_insert_with(Vec::new).push(raa_blocker);
72057206
}
7206-
if !during_init {
7207-
handle_new_monitor_update!(self, prev_hop.funding_txo, monitor_update, peer_state_opt,
7208-
peer_state, per_peer_state, chan);
7209-
} else {
7210-
// If we're running during init we cannot update a monitor directly -
7211-
// they probably haven't actually been loaded yet. Instead, push the
7212-
// monitor update as a background event.
7213-
self.pending_background_events.lock().unwrap().push(
7214-
BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
7215-
counterparty_node_id,
7216-
funding_txo: prev_hop.funding_txo,
7217-
channel_id: prev_hop.channel_id,
7218-
update: monitor_update.clone(),
7219-
});
7220-
}
7207+
handle_new_monitor_update!(self, prev_hop.funding_txo, monitor_update, peer_state_opt,
7208+
peer_state, per_peer_state, chan);
72217209
}
72227210
UpdateFulfillCommitFetch::DuplicateClaim {} => {
72237211
let (action_opt, raa_blocker_opt) = completion_action(None, true);
@@ -7332,26 +7320,10 @@ where
73327320
peer_state.monitor_update_blocked_actions.entry(chan_id).or_insert(Vec::new()).push(action);
73337321
}
73347322

7335-
if !during_init {
7336-
handle_new_monitor_update!(self, prev_hop.funding_txo, preimage_update, peer_state, peer_state, per_peer_state, logger, chan_id, POST_CHANNEL_CLOSE);
7337-
} else {
7338-
// If we're running during init we cannot update a monitor directly - they probably
7339-
// haven't actually been loaded yet. Instead, push the monitor update as a background
7340-
// event.
7341-
7342-
let in_flight_updates = peer_state.in_flight_monitor_updates
7343-
.entry(prev_hop.funding_txo)
7344-
.or_insert_with(Vec::new);
7345-
in_flight_updates.push(preimage_update.clone());
7346-
7347-
let event = BackgroundEvent::MonitorUpdateRegeneratedOnStartup {
7348-
counterparty_node_id,
7349-
funding_txo: prev_hop.funding_txo,
7350-
channel_id: prev_hop.channel_id,
7351-
update: preimage_update,
7352-
};
7353-
self.pending_background_events.lock().unwrap().push(event);
7354-
}
7323+
handle_new_monitor_update!(
7324+
self, prev_hop.funding_txo, preimage_update, peer_state, peer_state, per_peer_state,
7325+
counterparty_node_id, chan_id, POST_CHANNEL_CLOSE
7326+
);
73557327
}
73567328

73577329
fn finalize_claims(&self, sources: Vec<HTLCSource>) {
@@ -13743,14 +13715,20 @@ where
1374313715
}
1374413716
}
1374513717
}
13718+
let mut per_peer_state = per_peer_state.get(counterparty_node_id)
13719+
.expect("If we have pending updates for a channel it has to have an entry")
13720+
.lock().unwrap();
1374613721
if updated_id {
13747-
per_peer_state.get(counterparty_node_id)
13748-
.expect("If we have pending updates for a channel it has to have an entry")
13749-
.lock().unwrap()
13722+
per_peer_state
1375013723
.closed_channel_monitor_update_ids.entry(*channel_id)
1375113724
.and_modify(|v| *v = cmp::max(update.update_id, *v))
1375213725
.or_insert(update.update_id);
1375313726
}
13727+
let in_flight_updates = per_peer_state.in_flight_monitor_updates
13728+
.entry(*funding_txo)
13729+
.or_insert_with(Vec::new);
13730+
debug_assert!(!in_flight_updates.iter().any(|upd| upd == update));
13731+
in_flight_updates.push(update.clone());
1375413732
}
1375513733
pending_background_events.push(new_event);
1375613734
}

0 commit comments

Comments
 (0)