Merge #552

552: Make Local less than 2048 bytes r=stjepang a=taiki-e

Set `MAX_OBJECTS` to 62, and make the size of `Local` to 2040 bytes.

Closes #551

Co-authored-by: Taiki Endo <[email protected]>

crossbeam-epoch/src/internal.rs

@@ -55,7 +55,7 @@ use crate::sync::queue::Queue;
 
 /// Maximum number of objects a bag can contain.
 #[cfg(not(feature = "sanitize"))]
-const MAX_OBJECTS: usize = 64;
+const MAX_OBJECTS: usize = 62;
 #[cfg(feature = "sanitize")]
 const MAX_OBJECTS: usize = 4;
 
@@ -174,8 +174,6 @@ impl Default for Bag {
                 Deferred::new(no_op_func),
                 Deferred::new(no_op_func),
                 Deferred::new(no_op_func),
-                Deferred::new(no_op_func),
-                Deferred::new(no_op_func),
             ],
         };
         #[cfg(feature = "sanitize")]
@@ -374,6 +372,13 @@ pub struct Local {
     pin_count: Cell<Wrapping<usize>>,
 }
 
+// Make sure `Local` is less than or equal to 2048 bytes.
+// https://github.com/crossbeam-rs/crossbeam/issues/551
+#[test]
+fn local_size() {
+    assert_eq!(2040, core::mem::size_of::<Local>());
+}
+
 impl Local {
     /// Number of pinnings after which a participant will execute some deferred functions from the
     /// global queue.