Method queue_call

crates/wasmtime/src/runtime/component/concurrent.rs:2343–2576

Add the specified guest call to the "high priority" work item queue, to be started as soon as backpressure and/or reentrance rules allow. SAFETY: The raw pointer arguments must be valid references to guest functions (with the appropriate signatures) when the closures queued by this function are called.

(
        self,
        mut store: StoreContextMut<T>,
        guest_thread: QualifiedThreadId,
        callee: SendSyncPtr<VMFuncRef>,
        param_count: usize,
        result_count: usize,
       

    /// functions (with the appropriate signatures) when the closures queued by
    /// this function are called.
    unsafe fn queue_call<T: 'static>(
        self,
        mut store: StoreContextMut<T>,
        guest_thread: QualifiedThreadId,
        callee: SendSyncPtr<VMFuncRef>,
        param_count: usize,
        result_count: usize,
        async_: bool,
        callback: Option<SendSyncPtr<VMFuncRef>>,
        post_return: Option<SendSyncPtr<VMFuncRef>>,
    ) -> Result<()> {
        /// Return a closure which will call the specified function in the scope
        /// of the specified task.
        ///
        /// This will use `GuestTask::lower_params` to lower the parameters, but
        /// will not lift the result; instead, it returns a
        /// `[MaybeUninit<ValRaw>; MAX_FLAT_PARAMS]` from which the result, if
        /// any, may be lifted.  Note that an async-lifted export will have
        /// returned its result using the `task.return` intrinsic (or not
        /// returned a result at all, in the case of `task.cancel`), in which
        /// case the "result" of this call will either be a callback code or
        /// nothing.
        ///
        /// SAFETY: `callee` must be a valid `*mut VMFuncRef` at the time when
        /// the returned closure is called.
        unsafe fn make_call<T: 'static>(
            store: StoreContextMut<T>,
            guest_thread: QualifiedThreadId,
            callee: SendSyncPtr<VMFuncRef>,
            param_count: usize,
            result_count: usize,
        ) -> impl FnOnce(&mut dyn VMStore) -> Result<[MaybeUninit<ValRaw>; MAX_FLAT_PARAMS]>
        + Send
        + Sync
        + 'static
        + use<T> {
            let token = StoreToken::new(store);
            move |store: &mut dyn VMStore| {
                let mut storage = [MaybeUninit::uninit(); MAX_FLAT_PARAMS];

                store
                    .concurrent_state_mut()
                    .get_mut(guest_thread.thread)?
                    .state = GuestThreadState::Running;
                let task = store.concurrent_state_mut().get_mut(guest_thread.task)?;
                let lower = match task.lower_params.take() {
                    Some(l) => l,
                    None => bail_bug!("lower_params missing"),
                };

                lower(store, &mut storage[..param_count])?;

                let mut store = token.as_context_mut(store);

                // SAFETY: Per the contract documented in `make_call's`
                // documentation, `callee` must be a valid pointer.
                unsafe {
                    crate::Func::call_unchecked_raw(