summaryrefslogtreecommitdiffstats
path: root/third_party/rust/futures-util/benches_disabled/bilock.rs
diff options
context:
space:
mode:
Diffstat (limited to 'third_party/rust/futures-util/benches_disabled/bilock.rs')
-rw-r--r--third_party/rust/futures-util/benches_disabled/bilock.rs122
1 files changed, 122 insertions, 0 deletions
diff --git a/third_party/rust/futures-util/benches_disabled/bilock.rs b/third_party/rust/futures-util/benches_disabled/bilock.rs
new file mode 100644
index 0000000000..417f75d31e
--- /dev/null
+++ b/third_party/rust/futures-util/benches_disabled/bilock.rs
@@ -0,0 +1,122 @@
+#![feature(test)]
+
+#[cfg(feature = "bilock")]
+mod bench {
+ use futures::executor::LocalPool;
+ use futures::task::{Context, Waker};
+ use futures_util::lock::BiLock;
+ use futures_util::lock::BiLockAcquire;
+ use futures_util::lock::BiLockAcquired;
+ use futures_util::task::ArcWake;
+
+ use std::sync::Arc;
+ use test::Bencher;
+
+ fn notify_noop() -> Waker {
+ struct Noop;
+
+ impl ArcWake for Noop {
+ fn wake(_: &Arc<Self>) {}
+ }
+
+ ArcWake::into_waker(Arc::new(Noop))
+ }
+
+ /// Pseudo-stream which simply calls `lock.poll()` on `poll`
+ struct LockStream {
+ lock: BiLockAcquire<u32>,
+ }
+
+ impl LockStream {
+ fn new(lock: BiLock<u32>) -> Self {
+ Self { lock: lock.lock() }
+ }
+
+ /// Release a lock after it was acquired in `poll`,
+ /// so `poll` could be called again.
+ fn release_lock(&mut self, guard: BiLockAcquired<u32>) {
+ self.lock = guard.unlock().lock()
+ }
+ }
+
+ impl Stream for LockStream {
+ type Item = BiLockAcquired<u32>;
+ type Error = ();
+
+ fn poll_next(&mut self, cx: &mut Context<'_>) -> Poll<Option<Self::Item>, Self::Error> {
+ self.lock.poll(cx).map(|a| a.map(Some))
+ }
+ }
+
+ #[bench]
+ fn contended(b: &mut Bencher) {
+ let pool = LocalPool::new();
+ let mut exec = pool.executor();
+ let waker = notify_noop();
+ let mut map = task::LocalMap::new();
+ let mut waker = task::Context::new(&mut map, &waker, &mut exec);
+
+ b.iter(|| {
+ let (x, y) = BiLock::new(1);
+
+ let mut x = LockStream::new(x);
+ let mut y = LockStream::new(y);
+
+ for _ in 0..1000 {
+ let x_guard = match x.poll_next(&mut waker) {
+ Ok(Poll::Ready(Some(guard))) => guard,
+ _ => panic!(),
+ };
+
+ // Try poll second lock while first lock still holds the lock
+ match y.poll_next(&mut waker) {
+ Ok(Poll::Pending) => (),
+ _ => panic!(),
+ };
+
+ x.release_lock(x_guard);
+
+ let y_guard = match y.poll_next(&mut waker) {
+ Ok(Poll::Ready(Some(guard))) => guard,
+ _ => panic!(),
+ };
+
+ y.release_lock(y_guard);
+ }
+ (x, y)
+ });
+ }
+
+ #[bench]
+ fn lock_unlock(b: &mut Bencher) {
+ let pool = LocalPool::new();
+ let mut exec = pool.executor();
+ let waker = notify_noop();
+ let mut map = task::LocalMap::new();
+ let mut waker = task::Context::new(&mut map, &waker, &mut exec);
+
+ b.iter(|| {
+ let (x, y) = BiLock::new(1);
+
+ let mut x = LockStream::new(x);
+ let mut y = LockStream::new(y);
+
+ for _ in 0..1000 {
+ let x_guard = match x.poll_next(&mut waker) {
+ Ok(Poll::Ready(Some(guard))) => guard,
+ _ => panic!(),
+ };
+
+ x.release_lock(x_guard);
+
+ let y_guard = match y.poll_next(&mut waker) {
+ Ok(Poll::Ready(Some(guard))) => guard,
+ _ => panic!(),
+ };
+
+ y.release_lock(y_guard);
+ }
+ (x, y)
+ })
+ }
+}