Store boxed slice in KSymResolver

The Vec contains spare capacity for future extension of the contained
data, but we parse kernel symbols eagerly and then never modify them
again. As such, let's just use a boxed slice which is more space
efficient.

Signed-off-by: Daniel Müller <deso@posteo.net>

src/ksym.rs

@@ -75,7 +75,7 @@ impl<'ksym> From<&'ksym Ksym> for SymInfo<'ksym> {
 pub(crate) struct KSymResolver {
     /// An index over `syms` that is sorted by name.
     by_name_idx: OnceCell<Box<[usize]>>,
-    syms: Vec<Ksym>,
+    syms: Box<[Ksym]>,
     file_name: PathBuf,
 }
 
@@ -119,7 +119,7 @@ impl KSymResolver {
         syms.sort_by(|a, b| a.addr.cmp(&b.addr));
 
         let slf = Self {
-            syms,
+            syms: syms.into_boxed_slice(),
             by_name_idx: OnceCell::new(),
             file_name: path.to_path_buf(),
         };
@@ -197,7 +197,7 @@ impl Inspect for KSymResolver {
             return Ok(())
         }
 
-        for ksym in &self.syms {
+        for ksym in self.syms.iter() {
             let sym = SymInfo::from(ksym);
             if let ControlFlow::Break(()) = f(&sym) {
                 return Ok(())
@@ -229,7 +229,7 @@ mod tests {
     #[test]
     fn debug_repr() {
         let resolver = KSymResolver {
-            syms: Vec::new(),
+            syms: Box::default(),
             by_name_idx: OnceCell::new(),
             file_name: PathBuf::new(),
         };
@@ -321,7 +321,8 @@ mod tests {
                     addr: 0x12345,
                     name: "3".to_string(),
                 },
-            ],
+            ]
+            .into_boxed_slice(),
             by_name_idx: OnceCell::new(),
             file_name: PathBuf::new(),
         };
@@ -382,7 +383,8 @@ mod tests {
                     addr: 0x12345,
                     name: "z".to_string(),
                 },
-            ],
+            ]
+            .into_boxed_slice(),
             by_name_idx: OnceCell::new(),
             file_name: PathBuf::new(),
         };
@@ -423,7 +425,8 @@ mod tests {
                     addr: 0x12345,
                     name: "z".to_string(),
                 },
-            ],
+            ]
+            .into_boxed_slice(),
             by_name_idx: OnceCell::new(),
             file_name: PathBuf::new(),
         };