Fix 1.73.0 clippy lints (#5494)

Doesn't do an upgrade of rustc to 1.73.0 as we want to wait for the
cargo response of the curl CVE before updating. In preparation for an
update, we address the clippy lints that are newly firing in 1.73.0.

libs/utils/src/seqwait.rs

@@ -58,7 +58,7 @@ where
 // to get that.
 impl<T: Ord> PartialOrd for Waiter<T> {
     fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        other.wake_num.partial_cmp(&self.wake_num)
+        Some(self.cmp(other))
     }
 }
 

pageserver/src/deletion_queue.rs

@@ -186,7 +186,7 @@ where
     V: Serialize,
     I: AsRef<[u8]>,
 {
-    let transformed = input.iter().map(|(k, v)| (hex::encode(k), v.clone()));
+    let transformed = input.iter().map(|(k, v)| (hex::encode(k), v));
 
     transformed
         .collect::<HashMap<String, &V>>()
@@ -325,10 +325,7 @@ impl DeletionList {
             return false;
         }
 
-        let timeline_entry = tenant_entry
-            .timelines
-            .entry(*timeline)
-            .or_insert_with(Vec::new);
+        let timeline_entry = tenant_entry.timelines.entry(*timeline).or_default();
 
         let timeline_remote_path = remote_timeline_path(tenant, timeline);
 

pageserver/src/metrics.rs

@@ -691,10 +691,9 @@ impl StorageIoTime {
         .expect("failed to define a metric");
         let metrics = std::array::from_fn(|i| {
             let op = StorageIoOperation::from_repr(i).unwrap();
-            let metric = storage_io_histogram_vec
+            storage_io_histogram_vec
                 .get_metric_with_label_values(&[op.as_str()])
-                .unwrap();
-            metric
+                .unwrap()
         });
         Self { metrics }
     }

pageserver/src/tenant/storage_layer/delta_layer.rs

@@ -511,8 +511,7 @@ impl DeltaLayer {
     ///
     /// This variant is only used for debugging purposes, by the 'pagectl' binary.
     pub fn new_for_path(path: &Utf8Path, file: File) -> Result<Self> {
-        let mut summary_buf = Vec::new();
-        summary_buf.resize(PAGE_SZ, 0);
+        let mut summary_buf = vec![0; PAGE_SZ];
         file.read_exact_at(&mut summary_buf, 0)?;
         let summary = Summary::des_prefix(&summary_buf)?;
 

pageserver/src/tenant/storage_layer/image_layer.rs

@@ -400,8 +400,7 @@ impl ImageLayer {
     ///
     /// This variant is only used for debugging purposes, by the 'pagectl' binary.
     pub fn new_for_path(path: &Utf8Path, file: File) -> Result<ImageLayer> {
-        let mut summary_buf = Vec::new();
-        summary_buf.resize(PAGE_SZ, 0);
+        let mut summary_buf = vec![0; PAGE_SZ];
         file.read_exact_at(&mut summary_buf, 0)?;
         let summary = Summary::des_prefix(&summary_buf)?;
         let metadata = file

pageserver/src/tenant/timeline.rs

@@ -158,7 +158,7 @@ pub struct Timeline {
 
     /// The generation of the tenant that instantiated us: this is used for safety when writing remote objects.
     /// Never changes for the lifetime of this [`Timeline`] object.
-    ///  
+    ///
     /// This duplicates the generation stored in LocationConf, but that structure is mutable:
     /// this copy enforces the invariant that generatio doesn't change during a Tenant's lifetime.
     generation: Generation,
@@ -2363,7 +2363,7 @@ impl Timeline {
                 // during branch creation.
                 match ancestor.wait_to_become_active(ctx).await {
                     Ok(()) => {}
-                    Err(state) if state == TimelineState::Stopping => {
+                    Err(TimelineState::Stopping) => {
                         return Err(PageReconstructError::AncestorStopping(ancestor.timeline_id));
                     }
                     Err(state) => {

pageserver/src/walredo.rs

@@ -825,7 +825,7 @@ impl PostgresRedoManager {
         while nwrite < writebuf.len() {
             let n = loop {
                 match nix::poll::poll(&mut pollfds[0..2], wal_redo_timeout.as_millis() as i32) {
-                    Err(e) if e == nix::errno::Errno::EINTR => continue,
+                    Err(nix::errno::Errno::EINTR) => continue,
                     res => break res,
                 }
             }?;
@@ -917,7 +917,7 @@ impl PostgresRedoManager {
                 // and forward any logging information that the child writes to its stderr to the page server's log.
                 let n = loop {
                     match nix::poll::poll(&mut pollfds[1..3], wal_redo_timeout.as_millis() as i32) {
-                        Err(e) if e == nix::errno::Errno::EINTR => continue,
+                        Err(nix::errno::Errno::EINTR) => continue,
                         res => break res,
                     }
                 }?;

safekeeper/src/timeline.rs

@@ -723,9 +723,9 @@ impl Timeline {
             if horizon_segno <= 1 || horizon_segno <= shared_state.last_removed_segno {
                 return Ok(()); // nothing to do
             }
-            let remover = shared_state.sk.wal_store.remove_up_to(horizon_segno - 1);
+
             // release the lock before removing
-            remover
+            shared_state.sk.wal_store.remove_up_to(horizon_segno - 1)
         };
 
         // delete old WAL files