b14551d7ca
This commit changes the APIs in the `wasmtime` crate for configuring the pooling allocator. I plan on adding a few more configuration options in the near future and the current structure was feeling unwieldy for adding these new abstractions. The previous `struct`-based API has been replaced with a builder-style API in a similar shape as to `Config`. This is done to help make it easier to add more configuration options in the future through adding more methods as opposed to adding more field which could break prior initializations.
705 lines
21 KiB
Rust
705 lines
21 KiB
Rust
use anyhow::{anyhow, bail, Result};
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use std::future::Future;
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use std::pin::Pin;
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use std::task::{Context, Poll, RawWaker, RawWakerVTable, Waker};
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use wasmtime::*;
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fn async_store() -> Store<()> {
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Store::new(&Engine::new(Config::new().async_support(true)).unwrap(), ())
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}
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async fn run_smoke_test(store: &mut Store<()>, func: Func) {
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func.call_async(&mut *store, &[], &mut []).await.unwrap();
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func.call_async(&mut *store, &[], &mut []).await.unwrap();
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}
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async fn run_smoke_typed_test(store: &mut Store<()>, func: Func) {
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let func = func.typed::<(), (), _>(&store).unwrap();
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func.call_async(&mut *store, ()).await.unwrap();
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func.call_async(&mut *store, ()).await.unwrap();
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}
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#[tokio::test]
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async fn smoke() {
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let mut store = async_store();
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let func = Func::new_async(
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&mut store,
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FuncType::new(None, None),
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move |_caller, _params, _results| Box::new(async { Ok(()) }),
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);
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run_smoke_test(&mut store, func).await;
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run_smoke_typed_test(&mut store, func).await;
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let func = Func::wrap0_async(&mut store, move |_caller| Box::new(async { Ok(()) }));
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run_smoke_test(&mut store, func).await;
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run_smoke_typed_test(&mut store, func).await;
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}
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#[tokio::test]
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async fn smoke_host_func() -> Result<()> {
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let mut store = async_store();
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let mut linker = Linker::new(store.engine());
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linker.func_new_async(
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"",
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"first",
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FuncType::new(None, None),
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move |_caller, _params, _results| Box::new(async { Ok(()) }),
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)?;
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linker.func_wrap0_async("", "second", move |_caller| Box::new(async { Ok(()) }))?;
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let func = linker
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.get(&mut store, "", "first")
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.unwrap()
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.into_func()
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.unwrap();
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run_smoke_test(&mut store, func).await;
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run_smoke_typed_test(&mut store, func).await;
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let func = linker
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.get(&mut store, "", "second")
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.unwrap()
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.into_func()
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.unwrap();
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run_smoke_test(&mut store, func).await;
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run_smoke_typed_test(&mut store, func).await;
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Ok(())
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}
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#[tokio::test]
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async fn smoke_with_suspension() {
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let mut store = async_store();
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let func = Func::new_async(
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&mut store,
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FuncType::new(None, None),
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move |_caller, _params, _results| {
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Box::new(async {
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tokio::task::yield_now().await;
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Ok(())
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})
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},
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);
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run_smoke_test(&mut store, func).await;
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run_smoke_typed_test(&mut store, func).await;
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let func = Func::wrap0_async(&mut store, move |_caller| {
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Box::new(async {
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tokio::task::yield_now().await;
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Ok(())
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})
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});
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run_smoke_test(&mut store, func).await;
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run_smoke_typed_test(&mut store, func).await;
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}
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#[tokio::test]
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async fn smoke_host_func_with_suspension() -> Result<()> {
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let mut store = async_store();
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let mut linker = Linker::new(store.engine());
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linker.func_new_async(
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"",
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"first",
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FuncType::new(None, None),
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move |_caller, _params, _results| {
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Box::new(async {
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tokio::task::yield_now().await;
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Ok(())
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})
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},
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)?;
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linker.func_wrap0_async("", "second", move |_caller| {
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Box::new(async {
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tokio::task::yield_now().await;
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Ok(())
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})
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})?;
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let func = linker
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.get(&mut store, "", "first")
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.unwrap()
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.into_func()
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.unwrap();
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run_smoke_test(&mut store, func).await;
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run_smoke_typed_test(&mut store, func).await;
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let func = linker
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.get(&mut store, "", "second")
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.unwrap()
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.into_func()
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.unwrap();
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run_smoke_test(&mut store, func).await;
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run_smoke_typed_test(&mut store, func).await;
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Ok(())
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}
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#[tokio::test]
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async fn recursive_call() {
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let mut store = async_store();
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let async_wasm_func = Func::new_async(
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&mut store,
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FuncType::new(None, None),
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|_caller, _params, _results| {
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Box::new(async {
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tokio::task::yield_now().await;
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Ok(())
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})
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},
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);
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// Create an imported function which recursively invokes another wasm
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// function asynchronously, although this one is just our own host function
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// which suffices for this test.
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let func2 = Func::new_async(
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&mut store,
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FuncType::new(None, None),
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move |mut caller, _params, _results| {
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Box::new(async move {
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async_wasm_func
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.call_async(&mut caller, &[], &mut [])
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.await?;
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Ok(())
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})
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},
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);
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// Create an instance which calls an async import twice.
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let module = Module::new(
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store.engine(),
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"
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(module
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(import \"\" \"\" (func))
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(func (export \"\")
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;; call imported function which recursively does an async
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;; call
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call 0
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;; do it again, and our various pointers all better align
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call 0))
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",
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)
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.unwrap();
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let instance = Instance::new_async(&mut store, &module, &[func2.into()])
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.await
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.unwrap();
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let func = instance.get_func(&mut store, "").unwrap();
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func.call_async(&mut store, &[], &mut []).await.unwrap();
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}
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#[tokio::test]
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async fn suspend_while_suspending() {
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let mut store = async_store();
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// Create a synchronous function which calls our asynchronous function and
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// runs it locally. This shouldn't generally happen but we know everything
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// is synchronous in this test so it's fine for us to do this.
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//
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// The purpose of this test is intended to stress various cases in how
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// we manage pointers in ways that are not necessarily common but are still
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// possible in safe code.
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let async_thunk = Func::new_async(
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&mut store,
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FuncType::new(None, None),
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|_caller, _params, _results| Box::new(async { Ok(()) }),
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);
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let sync_call_async_thunk = Func::new(
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&mut store,
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FuncType::new(None, None),
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move |mut caller, _params, _results| {
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let mut future = Box::pin(async_thunk.call_async(&mut caller, &[], &mut []));
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let poll = future
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.as_mut()
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.poll(&mut Context::from_waker(&noop_waker()));
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assert!(poll.is_ready());
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Ok(())
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},
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);
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// A small async function that simply awaits once to pump the loops and
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// then finishes.
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let async_import = Func::new_async(
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&mut store,
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FuncType::new(None, None),
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move |_caller, _params, _results| {
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Box::new(async move {
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tokio::task::yield_now().await;
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Ok(())
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})
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},
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);
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let module = Module::new(
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store.engine(),
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"
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(module
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(import \"\" \"\" (func $sync_call_async_thunk))
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(import \"\" \"\" (func $async_import))
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(func (export \"\")
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;; Set some store-local state and pointers
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call $sync_call_async_thunk
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;; .. and hopefully it's all still configured correctly
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call $async_import))
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",
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)
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.unwrap();
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let instance = Instance::new_async(
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&mut store,
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&module,
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&[sync_call_async_thunk.into(), async_import.into()],
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)
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.await
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.unwrap();
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let func = instance.get_func(&mut store, "").unwrap();
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func.call_async(&mut store, &[], &mut []).await.unwrap();
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}
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#[tokio::test]
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async fn cancel_during_run() {
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let mut store = Store::new(&Engine::new(Config::new().async_support(true)).unwrap(), 0);
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let async_thunk = Func::new_async(
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&mut store,
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FuncType::new(None, None),
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move |mut caller, _params, _results| {
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assert_eq!(*caller.data(), 0);
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*caller.data_mut() = 1;
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let dtor = SetOnDrop(caller);
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Box::new(async move {
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drop(&dtor);
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tokio::task::yield_now().await;
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Ok(())
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})
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},
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);
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// Shouldn't have called anything yet...
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assert_eq!(*store.data(), 0);
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// Create our future, but as per async conventions this still doesn't
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// actually do anything. No wasm or host function has been called yet.
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let future = Box::pin(async_thunk.call_async(&mut store, &[], &mut []));
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// Push the future forward one tick, which actually runs the host code in
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// our async func. Our future is designed to be pending once, however.
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let future = PollOnce::new(future).await;
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// Now that our future is running (on a separate, now-suspended fiber), drop
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// the future and that should deallocate all the Rust bits as well.
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drop(future);
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assert_eq!(*store.data(), 2);
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struct SetOnDrop<'a>(Caller<'a, usize>);
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impl Drop for SetOnDrop<'_> {
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fn drop(&mut self) {
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assert_eq!(*self.0.data(), 1);
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*self.0.data_mut() = 2;
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}
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}
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}
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#[tokio::test]
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async fn iloop_with_fuel() {
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let engine = Engine::new(Config::new().async_support(true).consume_fuel(true)).unwrap();
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let mut store = Store::new(&engine, ());
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store.out_of_fuel_async_yield(1_000, 10);
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let module = Module::new(
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&engine,
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"
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(module
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(func (loop br 0))
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(start 0)
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)
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",
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)
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.unwrap();
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let instance = Instance::new_async(&mut store, &module, &[]);
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// This should yield a bunch of times but eventually finish
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let (_, pending) = CountPending::new(Box::pin(instance)).await;
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assert!(pending > 100);
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}
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#[tokio::test]
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async fn fuel_eventually_finishes() {
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let engine = Engine::new(Config::new().async_support(true).consume_fuel(true)).unwrap();
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let mut store = Store::new(&engine, ());
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store.out_of_fuel_async_yield(u64::max_value(), 10);
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let module = Module::new(
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&engine,
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"
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(module
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(func
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(local i32)
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i32.const 100
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local.set 0
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(loop
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local.get 0
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i32.const -1
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i32.add
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local.tee 0
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br_if 0)
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)
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(start 0)
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)
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",
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)
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.unwrap();
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let instance = Instance::new_async(&mut store, &module, &[]);
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instance.await.unwrap();
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}
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#[tokio::test]
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async fn async_with_pooling_stacks() {
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let mut pool = PoolingAllocationConfig::default();
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pool.instance_count(1)
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.instance_memory_pages(1)
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.instance_table_elements(0);
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let mut config = Config::new();
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config.async_support(true);
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config.allocation_strategy(InstanceAllocationStrategy::Pooling(pool));
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config.dynamic_memory_guard_size(0);
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config.static_memory_guard_size(0);
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config.static_memory_maximum_size(65536);
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let engine = Engine::new(&config).unwrap();
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let mut store = Store::new(&engine, ());
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let func = Func::new_async(
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&mut store,
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FuncType::new(None, None),
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move |_caller, _params, _results| Box::new(async { Ok(()) }),
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);
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run_smoke_test(&mut store, func).await;
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run_smoke_typed_test(&mut store, func).await;
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}
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#[tokio::test]
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async fn async_host_func_with_pooling_stacks() -> Result<()> {
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let mut pooling = PoolingAllocationConfig::default();
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pooling
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.instance_count(1)
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.instance_memory_pages(1)
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.instance_table_elements(0);
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let mut config = Config::new();
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config.async_support(true);
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config.allocation_strategy(InstanceAllocationStrategy::Pooling(pooling));
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config.dynamic_memory_guard_size(0);
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config.static_memory_guard_size(0);
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config.static_memory_maximum_size(65536);
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let mut store = Store::new(&Engine::new(&config)?, ());
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let mut linker = Linker::new(store.engine());
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linker.func_new_async(
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"",
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"",
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FuncType::new(None, None),
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move |_caller, _params, _results| Box::new(async { Ok(()) }),
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)?;
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let func = linker.get(&mut store, "", "").unwrap().into_func().unwrap();
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run_smoke_test(&mut store, func).await;
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run_smoke_typed_test(&mut store, func).await;
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Ok(())
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}
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async fn execute_across_threads<F: Future + Send + 'static>(future: F) {
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let future = PollOnce::new(Box::pin(future)).await;
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tokio::task::spawn_blocking(move || future)
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.await
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.expect("shouldn't panic");
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}
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#[tokio::test]
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async fn resume_separate_thread() {
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// This test will poll the following future on two threads. Simulating a
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// trap requires accessing TLS info, so that should be preserved correctly.
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execute_across_threads(async {
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let mut store = async_store();
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let module = Module::new(
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store.engine(),
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"
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(module
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(import \"\" \"\" (func))
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(start 0)
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)
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",
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)
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.unwrap();
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let func = Func::wrap0_async(&mut store, |_| {
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Box::new(async {
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tokio::task::yield_now().await;
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Err::<(), _>(anyhow!("test"))
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})
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});
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let result = Instance::new_async(&mut store, &module, &[func.into()]).await;
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assert!(result.is_err());
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})
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.await;
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}
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#[tokio::test]
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async fn resume_separate_thread2() {
|
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// This test will poll the following future on two threads. Catching a
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// signal requires looking up TLS information to determine whether it's a
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// trap to handle or not, so that must be preserved correctly across threads.
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execute_across_threads(async {
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let mut store = async_store();
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let module = Module::new(
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store.engine(),
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"
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(module
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(import \"\" \"\" (func))
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(func $start
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call 0
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unreachable)
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(start $start)
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)
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",
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)
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.unwrap();
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let func = Func::wrap0_async(&mut store, |_| {
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Box::new(async {
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tokio::task::yield_now().await;
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})
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});
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let result = Instance::new_async(&mut store, &module, &[func.into()]).await;
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assert!(result.is_err());
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})
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.await;
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}
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|
|
#[tokio::test]
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async fn resume_separate_thread3() {
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let _ = env_logger::try_init();
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|
|
|
// This test doesn't actually do anything with cross-thread polls, but
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// instead it deals with scheduling futures at "odd" times.
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//
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// First we'll set up a *synchronous* call which will initialize TLS info.
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// This call is simply to a host-defined function, but it still has the same
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// "enter into wasm" semantics since it's just calling a trampoline. In this
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// situation we'll set up the TLS info so it's in place while the body of
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// the function executes...
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let mut store = Store::new(&Engine::default(), None);
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let f = Func::wrap(&mut store, move |mut caller: Caller<'_, _>| -> Result<()> {
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// ... and the execution of this host-defined function (while the TLS
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// info is initialized), will set up a recursive call into wasm. This
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// recursive call will be done asynchronously so we can suspend it
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// halfway through.
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let f = async {
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let mut store = async_store();
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let module = Module::new(
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store.engine(),
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"
|
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(module
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(import \"\" \"\" (func))
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(start 0)
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)
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",
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)
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.unwrap();
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let func = Func::wrap0_async(&mut store, |_| {
|
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Box::new(async {
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tokio::task::yield_now().await;
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})
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});
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drop(Instance::new_async(&mut store, &module, &[func.into()]).await);
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unreachable!()
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};
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let mut future = Box::pin(f);
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let poll = future
|
|
.as_mut()
|
|
.poll(&mut Context::from_waker(&noop_waker()));
|
|
assert!(poll.is_pending());
|
|
|
|
// ... so at this point our call into wasm is suspended. The call into
|
|
// wasm will have overwritten TLS info, and we sure hope that the
|
|
// information is restored at this point. Note that we squirrel away the
|
|
// future somewhere else to get dropped later. If we were to drop it
|
|
// here then we would reenter the future's suspended stack to clean it
|
|
// up, which would do more alterations of TLS information we're not
|
|
// testing here.
|
|
*caller.data_mut() = Some(future);
|
|
|
|
// ... all in all this function will need access to the original TLS
|
|
// information to raise the trap. This TLS information should be
|
|
// restored even though the asynchronous execution is suspended.
|
|
bail!("")
|
|
});
|
|
assert!(f.call(&mut store, &[], &mut []).is_err());
|
|
}
|
|
|
|
#[tokio::test]
|
|
async fn recursive_async() -> Result<()> {
|
|
let mut store = async_store();
|
|
let m = Module::new(
|
|
store.engine(),
|
|
"(module
|
|
(func (export \"overflow\") call 0)
|
|
(func (export \"normal\"))
|
|
)",
|
|
)?;
|
|
let i = Instance::new_async(&mut store, &m, &[]).await?;
|
|
let overflow = i.get_typed_func::<(), (), _>(&mut store, "overflow")?;
|
|
let normal = i.get_typed_func::<(), (), _>(&mut store, "normal")?;
|
|
let f2 = Func::wrap0_async(&mut store, move |mut caller| {
|
|
Box::new(async move {
|
|
// recursive async calls shouldn't immediately stack overflow...
|
|
normal.call_async(&mut caller, ()).await?;
|
|
|
|
// ... but calls that actually stack overflow should indeed stack
|
|
// overflow
|
|
let err = overflow
|
|
.call_async(&mut caller, ())
|
|
.await
|
|
.unwrap_err()
|
|
.downcast::<Trap>()?;
|
|
assert_eq!(err, Trap::StackOverflow);
|
|
Ok(())
|
|
})
|
|
});
|
|
f2.call_async(&mut store, &[], &mut []).await?;
|
|
Ok(())
|
|
}
|
|
|
|
#[tokio::test]
|
|
async fn linker_module_command() -> Result<()> {
|
|
let mut store = async_store();
|
|
let mut linker = Linker::new(store.engine());
|
|
let module1 = Module::new(
|
|
store.engine(),
|
|
r#"
|
|
(module
|
|
(global $g (mut i32) (i32.const 0))
|
|
|
|
(func (export "_start"))
|
|
|
|
(func (export "g") (result i32)
|
|
global.get $g
|
|
i32.const 1
|
|
global.set $g)
|
|
)
|
|
"#,
|
|
)?;
|
|
let module2 = Module::new(
|
|
store.engine(),
|
|
r#"
|
|
(module
|
|
(import "" "g" (func (result i32)))
|
|
|
|
(func (export "get") (result i32)
|
|
call 0)
|
|
)
|
|
"#,
|
|
)?;
|
|
|
|
linker.module_async(&mut store, "", &module1).await?;
|
|
let instance = linker.instantiate_async(&mut store, &module2).await?;
|
|
let f = instance.get_typed_func::<(), i32, _>(&mut store, "get")?;
|
|
assert_eq!(f.call_async(&mut store, ()).await?, 0);
|
|
assert_eq!(f.call_async(&mut store, ()).await?, 0);
|
|
|
|
Ok(())
|
|
}
|
|
|
|
#[tokio::test]
|
|
async fn linker_module_reactor() -> Result<()> {
|
|
let mut store = async_store();
|
|
let mut linker = Linker::new(store.engine());
|
|
let module1 = Module::new(
|
|
store.engine(),
|
|
r#"
|
|
(module
|
|
(global $g (mut i32) (i32.const 0))
|
|
|
|
(func (export "g") (result i32)
|
|
global.get $g
|
|
i32.const 1
|
|
global.set $g)
|
|
)
|
|
"#,
|
|
)?;
|
|
let module2 = Module::new(
|
|
store.engine(),
|
|
r#"
|
|
(module
|
|
(import "" "g" (func (result i32)))
|
|
|
|
(func (export "get") (result i32)
|
|
call 0)
|
|
)
|
|
"#,
|
|
)?;
|
|
|
|
linker.module_async(&mut store, "", &module1).await?;
|
|
let instance = linker.instantiate_async(&mut store, &module2).await?;
|
|
let f = instance.get_typed_func::<(), i32, _>(&mut store, "get")?;
|
|
assert_eq!(f.call_async(&mut store, ()).await?, 0);
|
|
assert_eq!(f.call_async(&mut store, ()).await?, 1);
|
|
|
|
Ok(())
|
|
}
|
|
|
|
pub struct CountPending<F> {
|
|
future: F,
|
|
yields: usize,
|
|
}
|
|
|
|
impl<F> CountPending<F> {
|
|
pub fn new(future: F) -> CountPending<F> {
|
|
CountPending { future, yields: 0 }
|
|
}
|
|
}
|
|
|
|
impl<F> Future for CountPending<F>
|
|
where
|
|
F: Future + Unpin,
|
|
{
|
|
type Output = (F::Output, usize);
|
|
|
|
fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
|
|
match Pin::new(&mut self.future).poll(cx) {
|
|
Poll::Pending => {
|
|
self.yields += 1;
|
|
Poll::Pending
|
|
}
|
|
Poll::Ready(e) => Poll::Ready((e, self.yields)),
|
|
}
|
|
}
|
|
}
|
|
|
|
pub struct PollOnce<F>(Option<F>);
|
|
|
|
impl<F> PollOnce<F> {
|
|
pub fn new(future: F) -> PollOnce<F> {
|
|
PollOnce(Some(future))
|
|
}
|
|
}
|
|
|
|
impl<F> Future for PollOnce<F>
|
|
where
|
|
F: Future + Unpin,
|
|
{
|
|
type Output = F;
|
|
|
|
fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<F> {
|
|
let mut future = self.0.take().unwrap();
|
|
match Pin::new(&mut future).poll(cx) {
|
|
Poll::Pending => Poll::Ready(future),
|
|
Poll::Ready(_) => panic!("should not be ready"),
|
|
}
|
|
}
|
|
}
|
|
|
|
fn noop_waker() -> Waker {
|
|
const VTABLE: RawWakerVTable =
|
|
RawWakerVTable::new(|ptr| RawWaker::new(ptr, &VTABLE), |_| {}, |_| {}, |_| {});
|
|
const RAW: RawWaker = RawWaker::new(0 as *const (), &VTABLE);
|
|
unsafe { Waker::from_raw(RAW) }
|
|
}
|