bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ra-salsa/tests/parallel/true_parallel.rs')
-rw-r--r--crates/ra-salsa/tests/parallel/true_parallel.rs125
1 files changed, 125 insertions, 0 deletions
diff --git a/crates/ra-salsa/tests/parallel/true_parallel.rs b/crates/ra-salsa/tests/parallel/true_parallel.rs
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+++ b/crates/ra-salsa/tests/parallel/true_parallel.rs
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+use crate::setup::{Knobs, ParDatabase, ParDatabaseImpl, WithValue};
+use ra_salsa::ParallelDatabase;
+use std::panic::{self, AssertUnwindSafe};
+
+/// Test where two threads are executing sum. We show that they can
+/// both be executing sum in parallel by having thread1 wait for
+/// thread2 to send a signal before it leaves (similarly, thread2
+/// waits for thread1 to send a signal before it enters).
+#[test]
+fn true_parallel_different_keys() {
+ let mut db = ParDatabaseImpl::default();
+
+ db.set_input('a', 100);
+ db.set_input('b', 10);
+ db.set_input('c', 1);
+
+ // Thread 1 will signal stage 1 when it enters and wait for stage 2.
+ let thread1 = std::thread::spawn({
+ let db = db.snapshot();
+ move || {
+ let v = db
+ .knobs()
+ .sum_signal_on_entry
+ .with_value(1, || db.knobs().sum_wait_for_on_exit.with_value(2, || db.sum("a")));
+ v
+ }
+ });
+
+ // Thread 2 will wait_for stage 1 when it enters and signal stage 2
+ // when it leaves.
+ let thread2 = std::thread::spawn({
+ let db = db.snapshot();
+ move || {
+ let v = db
+ .knobs()
+ .sum_wait_for_on_entry
+ .with_value(1, || db.knobs().sum_signal_on_exit.with_value(2, || db.sum("b")));
+ v
+ }
+ });
+
+ assert_eq!(thread1.join().unwrap(), 100);
+ assert_eq!(thread2.join().unwrap(), 10);
+}
+
+/// Add a test that tries to trigger a conflict, where we fetch
+/// `sum("abc")` from two threads simultaneously, and of them
+/// therefore has to block.
+#[test]
+fn true_parallel_same_keys() {
+ let mut db = ParDatabaseImpl::default();
+
+ db.set_input('a', 100);
+ db.set_input('b', 10);
+ db.set_input('c', 1);
+
+ // Thread 1 will wait_for a barrier in the start of `sum`
+ let thread1 = std::thread::spawn({
+ let db = db.snapshot();
+ move || {
+ let v = db
+ .knobs()
+ .sum_signal_on_entry
+ .with_value(1, || db.knobs().sum_wait_for_on_entry.with_value(2, || db.sum("abc")));
+ v
+ }
+ });
+
+ // Thread 2 will wait until Thread 1 has entered sum and then --
+ // once it has set itself to block -- signal Thread 1 to
+ // continue. This way, we test out the mechanism of one thread
+ // blocking on another.
+ let thread2 = std::thread::spawn({
+ let db = db.snapshot();
+ move || {
+ db.knobs().signal.wait_for(1);
+ db.knobs().signal_on_will_block.set(2);
+ db.sum("abc")
+ }
+ });
+
+ assert_eq!(thread1.join().unwrap(), 111);
+ assert_eq!(thread2.join().unwrap(), 111);
+}
+
+/// Add a test that tries to trigger a conflict, where we fetch `sum("a")`
+/// from two threads simultaneously. After `thread2` begins blocking,
+/// we force `thread1` to panic and should see that propagate to `thread2`.
+#[test]
+fn true_parallel_propagate_panic() {
+ let mut db = ParDatabaseImpl::default();
+
+ db.set_input('a', 1);
+
+ // `thread1` will wait_for a barrier in the start of `sum`. Once it can
+ // continue, it will panic.
+ let thread1 = std::thread::spawn({
+ let db = db.snapshot();
+ move || {
+ let v = db.knobs().sum_signal_on_entry.with_value(1, || {
+ db.knobs()
+ .sum_wait_for_on_entry
+ .with_value(2, || db.knobs().sum_should_panic.with_value(true, || db.sum("a")))
+ });
+ v
+ }
+ });
+
+ // `thread2` will wait until `thread1` has entered sum and then -- once it
+ // has set itself to block -- signal `thread1` to continue.
+ let thread2 = std::thread::spawn({
+ let db = db.snapshot();
+ move || {
+ db.knobs().signal.wait_for(1);
+ db.knobs().signal_on_will_block.set(2);
+ db.sum("a")
+ }
+ });
+
+ let result1 = panic::catch_unwind(AssertUnwindSafe(|| thread1.join().unwrap()));
+ let result2 = panic::catch_unwind(AssertUnwindSafe(|| thread2.join().unwrap()));
+
+ assert!(result1.is_err());
+ assert!(result2.is_err());
+}