From 4eba32f29fceea5ab19e44900f8d3a6864989d55 Mon Sep 17 00:00:00 2001
From: Alex Auvolat <alex@adnab.me>
Date: Wed, 27 Mar 2024 13:47:06 +0100
Subject: [PATCH] [next-0.10] layout helper: rename & clarify updates to update
 trackers

---
 src/rpc/layout/helper.rs  | 71 +++++++++++++++++----------------------
 src/rpc/layout/manager.rs |  8 ++---
 2 files changed, 34 insertions(+), 45 deletions(-)

diff --git a/src/rpc/layout/helper.rs b/src/rpc/layout/helper.rs
index b15f7540..3a033ab2 100644
--- a/src/rpc/layout/helper.rs
+++ b/src/rpc/layout/helper.rs
@@ -238,19 +238,31 @@ impl LayoutHelper {
 
 	// ------------------ helpers for update tracking ---------------
 
-	pub(crate) fn update_trackers(&mut self, local_node_id: Uuid) {
+	pub(crate) fn update_update_trackers(&mut self, local_node_id: Uuid) {
 		// Ensure trackers for this node's values are up-to-date
 
 		// 1. Acknowledge the last layout version which is not currently
 		//    locked by an in-progress write operation
-		self.ack_max_free(local_node_id);
+		self.update_ack_to_max_free(local_node_id);
 
 		// 2. Assume the data on this node is sync'ed up at least to
 		//    the first layout version in the history
-		self.sync_first(local_node_id);
+		let first_version = self.inner().min_stored();
+		self.update(|layout| {
+			layout
+				.update_trackers
+				.sync_map
+				.set_max(local_node_id, first_version)
+		});
 
 		// 3. Acknowledge everyone has synced up to min(self.sync_map)
-		self.sync_ack(local_node_id);
+		let sync_map_min = self.sync_map_min;
+		self.update(|layout| {
+			layout
+				.update_trackers
+				.sync_ack_map
+				.set_max(local_node_id, sync_map_min)
+		});
 
 		debug!("ack_map: {:?}", self.inner().update_trackers.ack_map);
 		debug!("sync_map: {:?}", self.inner().update_trackers.sync_map);
@@ -260,42 +272,9 @@ impl LayoutHelper {
 		);
 	}
 
-	fn sync_first(&mut self, local_node_id: Uuid) {
-		let first_version = self.inner().min_stored();
-		self.update(|layout| {
-			layout
-				.update_trackers
-				.sync_map
-				.set_max(local_node_id, first_version)
-		});
-	}
-
-	fn sync_ack(&mut self, local_node_id: Uuid) {
-		let sync_map_min = self.sync_map_min;
-		self.update(|layout| {
-			layout
-				.update_trackers
-				.sync_ack_map
-				.set_max(local_node_id, sync_map_min)
-		});
-	}
-
-	pub(crate) fn ack_max_free(&mut self, local_node_id: Uuid) -> bool {
-		let max_ack = self.max_free_ack();
-		let changed = self.update(|layout| {
-			layout
-				.update_trackers
-				.ack_map
-				.set_max(local_node_id, max_ack)
-		});
-		if changed {
-			info!("ack_until updated to {}", max_ack);
-		}
-		changed
-	}
-
-	pub(crate) fn max_free_ack(&self) -> u64 {
-		self.versions()
+	pub(crate) fn update_ack_to_max_free(&mut self, local_node_id: Uuid) -> bool {
+		let max_free = self
+			.versions()
 			.iter()
 			.map(|x| x.version)
 			.skip_while(|v| {
@@ -305,6 +284,16 @@ impl LayoutHelper {
 					.unwrap_or(true)
 			})
 			.next()
-			.unwrap_or(self.current().version)
+			.unwrap_or(self.current().version);
+		let changed = self.update(|layout| {
+			layout
+				.update_trackers
+				.ack_map
+				.set_max(local_node_id, max_free)
+		});
+		if changed {
+			info!("ack_until updated to {}", max_free);
+		}
+		changed
 	}
 }
diff --git a/src/rpc/layout/manager.rs b/src/rpc/layout/manager.rs
index 0ca532ba..a0dcf50e 100644
--- a/src/rpc/layout/manager.rs
+++ b/src/rpc/layout/manager.rs
@@ -70,7 +70,7 @@ impl LayoutManager {
 			cluster_layout,
 			Default::default(),
 		);
-		cluster_layout.update_trackers(node_id.into());
+		cluster_layout.update_update_trackers(node_id.into());
 
 		let layout = Arc::new(RwLock::new(cluster_layout));
 		let change_notify = Arc::new(Notify::new());
@@ -134,7 +134,7 @@ impl LayoutManager {
 
 	fn ack_new_version(self: &Arc<Self>) {
 		let mut layout = self.layout.write().unwrap();
-		if layout.ack_max_free(self.node_id) {
+		if layout.update_ack_to_max_free(self.node_id) {
 			self.broadcast_update(SystemRpc::AdvertiseClusterLayoutTrackers(
 				layout.inner().update_trackers.clone(),
 			));
@@ -164,7 +164,7 @@ impl LayoutManager {
 
 		if !prev_layout_check || adv.check().is_ok() {
 			if layout.update(|l| l.merge(adv)) {
-				layout.update_trackers(self.node_id);
+				layout.update_update_trackers(self.node_id);
 				if prev_layout_check && !layout.is_check_ok() {
 					panic!("Merged two correct layouts and got an incorrect layout.");
 				}
@@ -182,7 +182,7 @@ impl LayoutManager {
 
 		if layout.inner().update_trackers != *adv {
 			if layout.update(|l| l.update_trackers.merge(adv)) {
-				layout.update_trackers(self.node_id);
+				layout.update_update_trackers(self.node_id);
 				assert!(layout.digest() != prev_digest);
 				return Some(layout.inner().update_trackers.clone());
 			}