start restoring parallel tests

tests/parallel/main.rs

@@ -1,7 +1,5 @@
-#[cfg(disabled)]
 mod setup;
 
-#[cfg(disabled)]
 mod parallel_cycle_all_recover;
 #[cfg(disabled)]
 mod parallel_cycle_mid_recover;
@@ -9,5 +7,4 @@ mod parallel_cycle_mid_recover;
 mod parallel_cycle_none_recover;
 #[cfg(disabled)]
 mod parallel_cycle_one_recover;
-#[cfg(disabled)]
 mod signal;

tests/parallel/parallel_cycle_all_recover.rs

@@ -2,6 +2,8 @@
 //! See `../cycles.rs` for a complete listing of cycle tests,
 //! both intra and cross thread.
 
+use salsa::Handle;
+
 use crate::setup::Database;
 use crate::setup::Knobs;
 
@@ -90,18 +92,18 @@ fn recover_b2(db: &dyn Db, _cycle: &salsa::Cycle, key: MyInput) -> i32 {
 
 #[test]
 fn execute() {
-    let db = Database::default();
-    db.knobs().signal_on_will_block.set(3);
+    let db = Handle::new(Database::default());
+    db.knobs().signal_on_will_block.store(3);
 
-    let input = MyInput::new(&db, 1);
+    let input = MyInput::new(&*db, 1);
 
     let thread_a = std::thread::spawn({
-        let db = db.snapshot();
+        let db = db.clone();
         move || a1(&*db, input)
     });
 
     let thread_b = std::thread::spawn({
-        let db = db.snapshot();
+        let db = db.clone();
         move || b1(&*db, input)
     });
 

tests/parallel/setup.rs

@@ -1,4 +1,4 @@
-use std::{cell::Cell, sync::Arc};
+use crossbeam::atomic::AtomicCell;
 
 use crate::signal::Signal;
 
@@ -15,14 +15,14 @@ pub(crate) trait Knobs {
 /// Various "knobs" that can be used to customize how the queries
 /// behave on one specific thread. Note that this state is
 /// intentionally thread-local (apart from `signal`).
-#[derive(Clone, Default)]
+#[derive(Default)]
 pub(crate) struct KnobsStruct {
     /// A kind of flexible barrier used to coordinate execution across
     /// threads to ensure we reach various weird states.
-    pub(crate) signal: Arc<Signal>,
+    pub(crate) signal: Signal,
 
     /// When this database is about to block, send a signal.
-    pub(crate) signal_on_will_block: Cell<usize>,
+    pub(crate) signal_on_will_block: AtomicCell<usize>,
 }
 
 #[salsa::db]
@@ -36,7 +36,7 @@ pub(crate) struct Database {
 impl salsa::Database for Database {
     fn salsa_event(&self, event: salsa::Event) {
         if let salsa::EventKind::WillBlockOn { .. } = event.kind {
-            self.signal(self.knobs().signal_on_will_block.get());
+            self.signal(self.knobs().signal_on_will_block.load());
         }
     }
 }