From 27d5a3a94f9bac6d88f4ea364142d98a8ff2dc20 Mon Sep 17 00:00:00 2001 From: Matt Corallo Date: Thu, 13 Sep 2018 11:34:26 -0400 Subject: [PATCH] Optimize check_spend_remote HTLC a tad by avoiding indirections Instead of hopping a pointer, we're only ever going to return one Transaction at max, so skip the Vec. Also avoid re-pubkey-converting the revocation key. --- src/ln/channelmonitor.rs | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/src/ln/channelmonitor.rs b/src/ln/channelmonitor.rs index 6de0a636..f037c673 100644 --- a/src/ln/channelmonitor.rs +++ b/src/ln/channelmonitor.rs @@ -1210,35 +1210,32 @@ impl ChannelMonitor { } /// Attempst to claim a remote HTLC-Success/HTLC-Timeout s outputs using the revocation key - fn check_spend_remote_htlc(&self, tx: &Transaction, commitment_number: u64) -> Vec { - let mut txn_to_broadcast = Vec::new(); - + fn check_spend_remote_htlc(&self, tx: &Transaction, commitment_number: u64) -> Option { let htlc_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers! macro_rules! ignore_error { ( $thing : expr ) => { match $thing { Ok(a) => a, - Err(_) => return txn_to_broadcast + Err(_) => return None } }; } let secret = self.get_secret(commitment_number).unwrap(); let per_commitment_key = ignore_error!(SecretKey::from_slice(&self.secp_ctx, &secret)); + let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key); let revocation_pubkey = match self.key_storage { KeyStorage::PrivMode { ref revocation_base_key, .. } => { - let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key); ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))) }, KeyStorage::SigsMode { ref revocation_base_key, .. } => { - let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key); ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key)) }, }; let delayed_key = match self.their_delayed_payment_base_key { - None => return txn_to_broadcast, - Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &their_delayed_payment_base_key)), + None => return None, + Some(their_delayed_payment_base_key) => ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &their_delayed_payment_base_key)), }; let redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.their_to_self_delay.unwrap(), &delayed_key); let revokeable_p2wsh = redeemscript.to_v0_p2wsh(); @@ -1290,9 +1287,8 @@ impl ChannelMonitor { spend_tx.input[0].witness.push(vec!(1)); spend_tx.input[0].witness.push(redeemscript.into_bytes()); - txn_to_broadcast.push(spend_tx); - } - txn_to_broadcast + Some(spend_tx) + } else { None } } fn broadcast_by_local_state(&self, local_tx: &LocalSignedTx) -> Vec { @@ -1369,8 +1365,10 @@ impl ChannelMonitor { } } else { let remote_commitment_txn_on_chain = self.remote_commitment_txn_on_chain.lock().unwrap(); - for commitment_number in remote_commitment_txn_on_chain.get(&txin.previous_output.txid) { - txn = self.check_spend_remote_htlc(tx, *commitment_number); + if let Some(commitment_number) = remote_commitment_txn_on_chain.get(&prevout.txid) { + if let Some(tx) = self.check_spend_remote_htlc(tx, *commitment_number) { + txn.push(tx); + } } } for tx in txn.iter() { -- 2.30.2