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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /vendor/rayon-core/src/spawn
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/rayon-core/src/spawn')
-rw-r--r--vendor/rayon-core/src/spawn/mod.rs168
-rw-r--r--vendor/rayon-core/src/spawn/test.rs243
2 files changed, 411 insertions, 0 deletions
diff --git a/vendor/rayon-core/src/spawn/mod.rs b/vendor/rayon-core/src/spawn/mod.rs
new file mode 100644
index 000000000..dfa47818e
--- /dev/null
+++ b/vendor/rayon-core/src/spawn/mod.rs
@@ -0,0 +1,168 @@
+use crate::job::*;
+use crate::registry::Registry;
+use crate::unwind;
+use std::mem;
+use std::sync::Arc;
+
+/// Fires off a task into the Rayon threadpool in the "static" or
+/// "global" scope. Just like a standard thread, this task is not
+/// tied to the current stack frame, and hence it cannot hold any
+/// references other than those with `'static` lifetime. If you want
+/// to spawn a task that references stack data, use [the `scope()`
+/// function][scope] to create a scope.
+///
+/// [scope]: fn.scope.html
+///
+/// Since tasks spawned with this function cannot hold references into
+/// the enclosing stack frame, you almost certainly want to use a
+/// `move` closure as their argument (otherwise, the closure will
+/// typically hold references to any variables from the enclosing
+/// function that you happen to use).
+///
+/// This API assumes that the closure is executed purely for its
+/// side-effects (i.e., it might send messages, modify data protected
+/// by a mutex, or some such thing).
+///
+/// There is no guaranteed order of execution for spawns, given that
+/// other threads may steal tasks at any time. However, they are
+/// generally prioritized in a LIFO order on the thread from which
+/// they were spawned. Other threads always steal from the other end of
+/// the deque, like FIFO order. The idea is that "recent" tasks are
+/// most likely to be fresh in the local CPU's cache, while other
+/// threads can steal older "stale" tasks. For an alternate approach,
+/// consider [`spawn_fifo()`] instead.
+///
+/// [`spawn_fifo()`]: fn.spawn_fifo.html
+///
+/// # Panic handling
+///
+/// If this closure should panic, the resulting panic will be
+/// propagated to the panic handler registered in the `ThreadPoolBuilder`,
+/// if any. See [`ThreadPoolBuilder::panic_handler()`][ph] for more
+/// details.
+///
+/// [ph]: struct.ThreadPoolBuilder.html#method.panic_handler
+///
+/// # Examples
+///
+/// This code creates a Rayon task that increments a global counter.
+///
+/// ```rust
+/// # use rayon_core as rayon;
+/// use std::sync::atomic::{AtomicUsize, Ordering, ATOMIC_USIZE_INIT};
+///
+/// static GLOBAL_COUNTER: AtomicUsize = ATOMIC_USIZE_INIT;
+///
+/// rayon::spawn(move || {
+/// GLOBAL_COUNTER.fetch_add(1, Ordering::SeqCst);
+/// });
+/// ```
+pub fn spawn<F>(func: F)
+where
+ F: FnOnce() + Send + 'static,
+{
+ // We assert that current registry has not terminated.
+ unsafe { spawn_in(func, &Registry::current()) }
+}
+
+/// Spawns an asynchronous job in `registry.`
+///
+/// Unsafe because `registry` must not yet have terminated.
+pub(super) unsafe fn spawn_in<F>(func: F, registry: &Arc<Registry>)
+where
+ F: FnOnce() + Send + 'static,
+{
+ // We assert that this does not hold any references (we know
+ // this because of the `'static` bound in the inferface);
+ // moreover, we assert that the code below is not supposed to
+ // be able to panic, and hence the data won't leak but will be
+ // enqueued into some deque for later execution.
+ let abort_guard = unwind::AbortIfPanic; // just in case we are wrong, and code CAN panic
+ let job_ref = spawn_job(func, registry);
+ registry.inject_or_push(job_ref);
+ mem::forget(abort_guard);
+}
+
+unsafe fn spawn_job<F>(func: F, registry: &Arc<Registry>) -> JobRef
+where
+ F: FnOnce() + Send + 'static,
+{
+ // Ensure that registry cannot terminate until this job has
+ // executed. This ref is decremented at the (*) below.
+ registry.increment_terminate_count();
+
+ Box::new(HeapJob::new({
+ let registry = Arc::clone(registry);
+ move || {
+ match unwind::halt_unwinding(func) {
+ Ok(()) => {}
+ Err(err) => {
+ registry.handle_panic(err);
+ }
+ }
+ registry.terminate(); // (*) permit registry to terminate now
+ }
+ }))
+ .as_job_ref()
+}
+
+/// Fires off a task into the Rayon threadpool in the "static" or
+/// "global" scope. Just like a standard thread, this task is not
+/// tied to the current stack frame, and hence it cannot hold any
+/// references other than those with `'static` lifetime. If you want
+/// to spawn a task that references stack data, use [the `scope_fifo()`
+/// function](fn.scope_fifo.html) to create a scope.
+///
+/// The behavior is essentially the same as [the `spawn`
+/// function](fn.spawn.html), except that calls from the same thread
+/// will be prioritized in FIFO order. This is similar to the now-
+/// deprecated [`breadth_first`] option, except the effect is isolated
+/// to relative `spawn_fifo` calls, not all threadpool tasks.
+///
+/// For more details on this design, see Rayon [RFC #1].
+///
+/// [`breadth_first`]: struct.ThreadPoolBuilder.html#method.breadth_first
+/// [RFC #1]: https://github.com/rayon-rs/rfcs/blob/master/accepted/rfc0001-scope-scheduling.md
+///
+/// # Panic handling
+///
+/// If this closure should panic, the resulting panic will be
+/// propagated to the panic handler registered in the `ThreadPoolBuilder`,
+/// if any. See [`ThreadPoolBuilder::panic_handler()`][ph] for more
+/// details.
+///
+/// [ph]: struct.ThreadPoolBuilder.html#method.panic_handler
+pub fn spawn_fifo<F>(func: F)
+where
+ F: FnOnce() + Send + 'static,
+{
+ // We assert that current registry has not terminated.
+ unsafe { spawn_fifo_in(func, &Registry::current()) }
+}
+
+/// Spawns an asynchronous FIFO job in `registry.`
+///
+/// Unsafe because `registry` must not yet have terminated.
+pub(super) unsafe fn spawn_fifo_in<F>(func: F, registry: &Arc<Registry>)
+where
+ F: FnOnce() + Send + 'static,
+{
+ // We assert that this does not hold any references (we know
+ // this because of the `'static` bound in the inferface);
+ // moreover, we assert that the code below is not supposed to
+ // be able to panic, and hence the data won't leak but will be
+ // enqueued into some deque for later execution.
+ let abort_guard = unwind::AbortIfPanic; // just in case we are wrong, and code CAN panic
+ let job_ref = spawn_job(func, registry);
+
+ // If we're in the pool, use our thread's private fifo for this thread to execute
+ // in a locally-FIFO order. Otherwise, just use the pool's global injector.
+ match registry.current_thread() {
+ Some(worker) => worker.push_fifo(job_ref),
+ None => registry.inject(&[job_ref]),
+ }
+ mem::forget(abort_guard);
+}
+
+#[cfg(test)]
+mod test;
diff --git a/vendor/rayon-core/src/spawn/test.rs b/vendor/rayon-core/src/spawn/test.rs
new file mode 100644
index 000000000..761fafc77
--- /dev/null
+++ b/vendor/rayon-core/src/spawn/test.rs
@@ -0,0 +1,243 @@
+use crate::scope;
+use std::any::Any;
+use std::sync::mpsc::channel;
+use std::sync::Mutex;
+
+use super::{spawn, spawn_fifo};
+use crate::ThreadPoolBuilder;
+
+#[test]
+fn spawn_then_join_in_worker() {
+ let (tx, rx) = channel();
+ scope(move |_| {
+ spawn(move || tx.send(22).unwrap());
+ });
+ assert_eq!(22, rx.recv().unwrap());
+}
+
+#[test]
+fn spawn_then_join_outside_worker() {
+ let (tx, rx) = channel();
+ spawn(move || tx.send(22).unwrap());
+ assert_eq!(22, rx.recv().unwrap());
+}
+
+#[test]
+fn panic_fwd() {
+ let (tx, rx) = channel();
+
+ let tx = Mutex::new(tx);
+ let panic_handler = move |err: Box<dyn Any + Send>| {
+ let tx = tx.lock().unwrap();
+ if let Some(&msg) = err.downcast_ref::<&str>() {
+ if msg == "Hello, world!" {
+ tx.send(1).unwrap();
+ } else {
+ tx.send(2).unwrap();
+ }
+ } else {
+ tx.send(3).unwrap();
+ }
+ };
+
+ let builder = ThreadPoolBuilder::new().panic_handler(panic_handler);
+
+ builder
+ .build()
+ .unwrap()
+ .spawn(move || panic!("Hello, world!"));
+
+ assert_eq!(1, rx.recv().unwrap());
+}
+
+/// Test what happens when the thread-pool is dropped but there are
+/// still active asynchronous tasks. We expect the thread-pool to stay
+/// alive and executing until those threads are complete.
+#[test]
+fn termination_while_things_are_executing() {
+ let (tx0, rx0) = channel();
+ let (tx1, rx1) = channel();
+
+ // Create a thread-pool and spawn some code in it, but then drop
+ // our reference to it.
+ {
+ let thread_pool = ThreadPoolBuilder::new().build().unwrap();
+ thread_pool.spawn(move || {
+ let data = rx0.recv().unwrap();
+
+ // At this point, we know the "main" reference to the
+ // `ThreadPool` has been dropped, but there are still
+ // active threads. Launch one more.
+ spawn(move || {
+ tx1.send(data).unwrap();
+ });
+ });
+ }
+
+ tx0.send(22).unwrap();
+ let v = rx1.recv().unwrap();
+ assert_eq!(v, 22);
+}
+
+#[test]
+fn custom_panic_handler_and_spawn() {
+ let (tx, rx) = channel();
+
+ // Create a parallel closure that will send panics on the
+ // channel; since the closure is potentially executed in parallel
+ // with itself, we have to wrap `tx` in a mutex.
+ let tx = Mutex::new(tx);
+ let panic_handler = move |e: Box<dyn Any + Send>| {
+ tx.lock().unwrap().send(e).unwrap();
+ };
+
+ // Execute an async that will panic.
+ let builder = ThreadPoolBuilder::new().panic_handler(panic_handler);
+ builder.build().unwrap().spawn(move || {
+ panic!("Hello, world!");
+ });
+
+ // Check that we got back the panic we expected.
+ let error = rx.recv().unwrap();
+ if let Some(&msg) = error.downcast_ref::<&str>() {
+ assert_eq!(msg, "Hello, world!");
+ } else {
+ panic!("did not receive a string from panic handler");
+ }
+}
+
+#[test]
+fn custom_panic_handler_and_nested_spawn() {
+ let (tx, rx) = channel();
+
+ // Create a parallel closure that will send panics on the
+ // channel; since the closure is potentially executed in parallel
+ // with itself, we have to wrap `tx` in a mutex.
+ let tx = Mutex::new(tx);
+ let panic_handler = move |e| {
+ tx.lock().unwrap().send(e).unwrap();
+ };
+
+ // Execute an async that will (eventually) panic.
+ const PANICS: usize = 3;
+ let builder = ThreadPoolBuilder::new().panic_handler(panic_handler);
+ builder.build().unwrap().spawn(move || {
+ // launch 3 nested spawn-asyncs; these should be in the same
+ // thread-pool and hence inherit the same panic handler
+ for _ in 0..PANICS {
+ spawn(move || {
+ panic!("Hello, world!");
+ });
+ }
+ });
+
+ // Check that we get back the panics we expected.
+ for _ in 0..PANICS {
+ let error = rx.recv().unwrap();
+ if let Some(&msg) = error.downcast_ref::<&str>() {
+ assert_eq!(msg, "Hello, world!");
+ } else {
+ panic!("did not receive a string from panic handler");
+ }
+ }
+}
+
+macro_rules! test_order {
+ ($outer_spawn:ident, $inner_spawn:ident) => {{
+ let builder = ThreadPoolBuilder::new().num_threads(1);
+ let pool = builder.build().unwrap();
+ let (tx, rx) = channel();
+ pool.install(move || {
+ for i in 0..10 {
+ let tx = tx.clone();
+ $outer_spawn(move || {
+ for j in 0..10 {
+ let tx = tx.clone();
+ $inner_spawn(move || {
+ tx.send(i * 10 + j).unwrap();
+ });
+ }
+ });
+ }
+ });
+ rx.iter().collect::<Vec<i32>>()
+ }};
+}
+
+#[test]
+fn lifo_order() {
+ // In the absence of stealing, `spawn()` jobs on a thread will run in LIFO order.
+ let vec = test_order!(spawn, spawn);
+ let expected: Vec<i32> = (0..100).rev().collect(); // LIFO -> reversed
+ assert_eq!(vec, expected);
+}
+
+#[test]
+fn fifo_order() {
+ // In the absence of stealing, `spawn_fifo()` jobs on a thread will run in FIFO order.
+ let vec = test_order!(spawn_fifo, spawn_fifo);
+ let expected: Vec<i32> = (0..100).collect(); // FIFO -> natural order
+ assert_eq!(vec, expected);
+}
+
+#[test]
+fn lifo_fifo_order() {
+ // LIFO on the outside, FIFO on the inside
+ let vec = test_order!(spawn, spawn_fifo);
+ let expected: Vec<i32> = (0..10)
+ .rev()
+ .flat_map(|i| (0..10).map(move |j| i * 10 + j))
+ .collect();
+ assert_eq!(vec, expected);
+}
+
+#[test]
+fn fifo_lifo_order() {
+ // FIFO on the outside, LIFO on the inside
+ let vec = test_order!(spawn_fifo, spawn);
+ let expected: Vec<i32> = (0..10)
+ .flat_map(|i| (0..10).rev().map(move |j| i * 10 + j))
+ .collect();
+ assert_eq!(vec, expected);
+}
+
+macro_rules! spawn_send {
+ ($spawn:ident, $tx:ident, $i:expr) => {{
+ let tx = $tx.clone();
+ $spawn(move || tx.send($i).unwrap());
+ }};
+}
+
+/// Test mixed spawns pushing a series of numbers, interleaved such
+/// such that negative values are using the second kind of spawn.
+macro_rules! test_mixed_order {
+ ($pos_spawn:ident, $neg_spawn:ident) => {{
+ let builder = ThreadPoolBuilder::new().num_threads(1);
+ let pool = builder.build().unwrap();
+ let (tx, rx) = channel();
+ pool.install(move || {
+ spawn_send!($pos_spawn, tx, 0);
+ spawn_send!($neg_spawn, tx, -1);
+ spawn_send!($pos_spawn, tx, 1);
+ spawn_send!($neg_spawn, tx, -2);
+ spawn_send!($pos_spawn, tx, 2);
+ spawn_send!($neg_spawn, tx, -3);
+ spawn_send!($pos_spawn, tx, 3);
+ });
+ rx.iter().collect::<Vec<i32>>()
+ }};
+}
+
+#[test]
+fn mixed_lifo_fifo_order() {
+ let vec = test_mixed_order!(spawn, spawn_fifo);
+ let expected = vec![3, -1, 2, -2, 1, -3, 0];
+ assert_eq!(vec, expected);
+}
+
+#[test]
+fn mixed_fifo_lifo_order() {
+ let vec = test_mixed_order!(spawn_fifo, spawn);
+ let expected = vec![0, -3, 1, -2, 2, -1, 3];
+ assert_eq!(vec, expected);
+}