Merge pull request #2090 from TheBlueMatt/2023-03-mon-wake-bp
[rust-lightning] / lightning-background-processor / src / lib.rs
index 541813c7e42c72f68568ec1c397fc531156d158c..2b150cb3025afd8775a1a2b21143479d944195a3 100644 (file)
@@ -38,6 +38,8 @@ use lightning::routing::router::Router;
 use lightning::routing::scoring::{Score, WriteableScore};
 use lightning::util::logger::Logger;
 use lightning::util::persist::Persister;
+#[cfg(feature = "std")]
+use lightning::util::wakers::Sleeper;
 use lightning_rapid_gossip_sync::RapidGossipSync;
 
 use core::ops::Deref;
@@ -114,6 +116,13 @@ const FIRST_NETWORK_PRUNE_TIMER: u64 = 60;
 #[cfg(test)]
 const FIRST_NETWORK_PRUNE_TIMER: u64 = 1;
 
+#[cfg(feature = "futures")]
+/// core::cmp::min is not currently const, so we define a trivial (and equivalent) replacement
+const fn min_u64(a: u64, b: u64) -> u64 { if a < b { a } else { b } }
+#[cfg(feature = "futures")]
+const FASTEST_TIMER: u64 = min_u64(min_u64(FRESHNESS_TIMER, PING_TIMER),
+       min_u64(SCORER_PERSIST_TIMER, FIRST_NETWORK_PRUNE_TIMER));
+
 /// Either [`P2PGossipSync`] or [`RapidGossipSync`].
 pub enum GossipSync<
        P: Deref<Target = P2PGossipSync<G, U, L>>,
@@ -256,7 +265,8 @@ macro_rules! define_run_body {
        ($persister: ident, $chain_monitor: ident, $process_chain_monitor_events: expr,
         $channel_manager: ident, $process_channel_manager_events: expr,
         $gossip_sync: ident, $peer_manager: ident, $logger: ident, $scorer: ident,
-        $loop_exit_check: expr, $await: expr, $get_timer: expr, $timer_elapsed: expr)
+        $loop_exit_check: expr, $await: expr, $get_timer: expr, $timer_elapsed: expr,
+        $check_slow_await: expr)
        => { {
                log_trace!($logger, "Calling ChannelManager's timer_tick_occurred on startup");
                $channel_manager.timer_tick_occurred();
@@ -286,9 +296,10 @@ macro_rules! define_run_body {
 
                        // We wait up to 100ms, but track how long it takes to detect being put to sleep,
                        // see `await_start`'s use below.
-                       let mut await_start = $get_timer(1);
+                       let mut await_start = None;
+                       if $check_slow_await { await_start = Some($get_timer(1)); }
                        let updates_available = $await;
-                       let await_slow = $timer_elapsed(&mut await_start, 1);
+                       let await_slow = if $check_slow_await { $timer_elapsed(&mut await_start.unwrap(), 1) } else { false };
 
                        if updates_available {
                                log_trace!($logger, "Persisting ChannelManager...");
@@ -388,15 +399,20 @@ pub(crate) mod futures_util {
        use core::task::{Poll, Waker, RawWaker, RawWakerVTable};
        use core::pin::Pin;
        use core::marker::Unpin;
-       pub(crate) struct Selector<A: Future<Output=()> + Unpin, B: Future<Output=bool> + Unpin> {
+       pub(crate) struct Selector<
+               A: Future<Output=()> + Unpin, B: Future<Output=()> + Unpin, C: Future<Output=bool> + Unpin
+       > {
                pub a: A,
                pub b: B,
+               pub c: C,
        }
        pub(crate) enum SelectorOutput {
-               A, B(bool),
+               A, B, C(bool),
        }
 
-       impl<A: Future<Output=()> + Unpin, B: Future<Output=bool> + Unpin> Future for Selector<A, B> {
+       impl<
+               A: Future<Output=()> + Unpin, B: Future<Output=()> + Unpin, C: Future<Output=bool> + Unpin
+       > Future for Selector<A, B, C> {
                type Output = SelectorOutput;
                fn poll(mut self: Pin<&mut Self>, ctx: &mut core::task::Context<'_>) -> Poll<SelectorOutput> {
                        match Pin::new(&mut self.a).poll(ctx) {
@@ -404,7 +420,11 @@ pub(crate) mod futures_util {
                                Poll::Pending => {},
                        }
                        match Pin::new(&mut self.b).poll(ctx) {
-                               Poll::Ready(res) => { return Poll::Ready(SelectorOutput::B(res)); },
+                               Poll::Ready(()) => { return Poll::Ready(SelectorOutput::B); },
+                               Poll::Pending => {},
+                       }
+                       match Pin::new(&mut self.c).poll(ctx) {
+                               Poll::Ready(res) => { return Poll::Ready(SelectorOutput::C(res)); },
                                Poll::Pending => {},
                        }
                        Poll::Pending
@@ -438,6 +458,11 @@ use core::task;
 /// feature, doing so will skip calling [`NetworkGraph::remove_stale_channels_and_tracking`],
 /// you should call [`NetworkGraph::remove_stale_channels_and_tracking_with_time`] regularly
 /// manually instead.
+///
+/// The `mobile_interruptable_platform` flag should be set if we're currently running on a
+/// mobile device, where we may need to check for interruption of the application regularly. If you
+/// are unsure, you should set the flag, as the performance impact of it is minimal unless there
+/// are hundreds or thousands of simultaneous process calls running.
 #[cfg(feature = "futures")]
 pub async fn process_events_async<
        'a,
@@ -473,7 +498,7 @@ pub async fn process_events_async<
 >(
        persister: PS, event_handler: EventHandler, chain_monitor: M, channel_manager: CM,
        gossip_sync: GossipSync<PGS, RGS, G, UL, L>, peer_manager: PM, logger: L, scorer: Option<S>,
-       sleeper: Sleeper,
+       sleeper: Sleeper, mobile_interruptable_platform: bool,
 ) -> Result<(), lightning::io::Error>
 where
        UL::Target: 'static + UtxoLookup,
@@ -514,11 +539,13 @@ where
                gossip_sync, peer_manager, logger, scorer, should_break, {
                        let fut = Selector {
                                a: channel_manager.get_persistable_update_future(),
-                               b: sleeper(Duration::from_millis(100)),
+                               b: chain_monitor.get_update_future(),
+                               c: sleeper(if mobile_interruptable_platform { Duration::from_millis(100) } else { Duration::from_secs(FASTEST_TIMER) }),
                        };
                        match fut.await {
                                SelectorOutput::A => true,
-                               SelectorOutput::B(exit) => {
+                               SelectorOutput::B => false,
+                               SelectorOutput::C(exit) => {
                                        should_break = exit;
                                        false
                                }
@@ -528,7 +555,7 @@ where
                        let mut waker = dummy_waker();
                        let mut ctx = task::Context::from_waker(&mut waker);
                        core::pin::Pin::new(fut).poll(&mut ctx).is_ready()
-               })
+               }, mobile_interruptable_platform)
 }
 
 #[cfg(feature = "std")]
@@ -643,8 +670,11 @@ impl BackgroundProcessor {
                        define_run_body!(persister, chain_monitor, chain_monitor.process_pending_events(&event_handler),
                                channel_manager, channel_manager.process_pending_events(&event_handler),
                                gossip_sync, peer_manager, logger, scorer, stop_thread.load(Ordering::Acquire),
-                               channel_manager.await_persistable_update_timeout(Duration::from_millis(100)),
-                               |_| Instant::now(), |time: &Instant, dur| time.elapsed().as_secs() > dur)
+                               Sleeper::from_two_futures(
+                                       channel_manager.get_persistable_update_future(),
+                                       chain_monitor.get_update_future()
+                               ).wait_timeout(Duration::from_millis(100)),
+                               |_| Instant::now(), |time: &Instant, dur| time.elapsed().as_secs() > dur, false)
                });
                Self { stop_thread: stop_thread_clone, thread_handle: Some(handle) }
        }