From 685c6f0b20723379fede80547b11963236bf90e2 Mon Sep 17 00:00:00 2001 From: koniifer Date: Tue, 26 Nov 2024 19:32:19 +0000 Subject: [PATCH] task scheduler weirdness --- kernel/src/holeybytes/ecah.rs | 3 +- kernel/src/holeybytes/mod.rs | 7 +- kernel/src/kmain.rs | 2 +- kernel/src/lib.rs | 7 +- kernel/src/task.rs | 154 ++++++++++++++++------------------ 5 files changed, 85 insertions(+), 88 deletions(-) diff --git a/kernel/src/holeybytes/ecah.rs b/kernel/src/holeybytes/ecah.rs index 67576f4..a34f683 100644 --- a/kernel/src/holeybytes/ecah.rs +++ b/kernel/src/holeybytes/ecah.rs @@ -33,7 +33,7 @@ unsafe fn x86_in(address: u16) -> T { } #[inline(always)] -pub fn handler(vm: &mut Vm) { +pub fn handler(vm: &mut Vm, pid: &usize) { let ecall_number = vm.registers[2].cast::(); match ecall_number { @@ -209,7 +209,6 @@ pub fn handler(vm: &mut Vm) { let buffer_id = vm.registers[3].cast::(); let map_ptr = vm.registers[4].cast::(); let max_length = vm.registers[5].cast::(); - let mut buffs = IPC_BUFFERS.lock(); let buff: &mut IpcBuffer = match buffs.get_mut(&buffer_id) { Some(buff) => buff, diff --git a/kernel/src/holeybytes/mod.rs b/kernel/src/holeybytes/mod.rs index 2c4dbab..ab68d04 100644 --- a/kernel/src/holeybytes/mod.rs +++ b/kernel/src/holeybytes/mod.rs @@ -65,7 +65,12 @@ impl<'p> Future for ExecThread { return Poll::Ready(Err(err)); } Ok(VmRunOk::End) => return Poll::Ready(Ok(())), - Ok(VmRunOk::Ecall) => ecah::handler(&mut self.vm), + Ok(VmRunOk::Ecall) => ecah::handler( + &mut self.vm, + cx.ext() + .downcast_ref() + .expect("PID did not exist in Context"), + ), Ok(VmRunOk::Timer) => (), Ok(VmRunOk::Breakpoint) => { log::error!( diff --git a/kernel/src/kmain.rs b/kernel/src/kmain.rs index a9f7bc6..928dbe5 100644 --- a/kernel/src/kmain.rs +++ b/kernel/src/kmain.rs @@ -122,7 +122,7 @@ pub fn kmain(_cmdline: &str, boot_modules: BootModules) -> ! { if cmd_len > 0 { thr.set_arguments(cmd.as_ptr() as u64, cmd_len); } - executor.spawn(Box::pin(async move { + executor.spawn(Box::pin(async { if let Err(e) = thr.await { log::error!("{e:?}"); } diff --git a/kernel/src/lib.rs b/kernel/src/lib.rs index 52956ec..cf68a83 100644 --- a/kernel/src/lib.rs +++ b/kernel/src/lib.rs @@ -10,9 +10,11 @@ abi_x86_interrupt, lazy_get, alloc_error_handler, + local_waker, + context_ext, ptr_sub_ptr, naked_functions, - pointer_is_aligned_to, + pointer_is_aligned_to )] #![allow(dead_code, internal_features, static_mut_refs)] extern crate alloc; @@ -35,8 +37,7 @@ mod utils; // #[cfg(feature = "tests")] mod ktest; -use alloc::string::ToString; -use versioning::Version; +use {alloc::string::ToString, versioning::Version}; /// Kernel's version pub const VERSION: Version = Version { diff --git a/kernel/src/task.rs b/kernel/src/task.rs index 3326871..01c6688 100644 --- a/kernel/src/task.rs +++ b/kernel/src/task.rs @@ -3,7 +3,8 @@ use { core::{ future::Future, pin::Pin, - task::{Context, Poll, RawWaker, RawWakerVTable, Waker}, + sync::atomic::{AtomicBool, Ordering}, + task::{Context, ContextBuilder, Poll, RawWaker, RawWakerVTable, Waker}, }, crossbeam_queue::SegQueue, slab::Slab, @@ -14,7 +15,6 @@ pub fn yield_now() -> impl Future { impl Future for YieldNow { type Output = (); - #[inline(always)] fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll { if self.0 { Poll::Ready(()) @@ -29,53 +29,70 @@ pub fn yield_now() -> impl Future { YieldNow(false) } +pub trait Process: Future + Send {} +impl + Send> Process for T {} + pub struct Executor { tasks: Slab, - task_queue: Arc, + task_queue: Arc>, } impl Executor { pub fn new() -> Self { Self { tasks: Slab::new(), - task_queue: Arc::new(TaskQueue::new()), + task_queue: Arc::new(SegQueue::new()), } } - #[inline] - pub fn spawn(&mut self, future: Pin + Send>>) -> usize { + pub fn spawn(&mut self, future: Pin>) -> usize { let id = self.tasks.insert(Task::new(future)); - self.task_queue.queue.push(id); + self.task_queue.push(id); + id } + pub fn pause(&mut self, id: usize) { + if let Some(task) = self.tasks.get(id) { + task.set_paused(true); + } + } + + pub fn unpause(&mut self, id: usize) { + if let Some(task) = self.tasks.get(id) { + task.set_paused(false); + self.task_queue.push(id); + } + } + pub fn run(&mut self) { let mut task_batch = [0; 32]; - let mut batch_len = 0; - loop { - self.task_queue.batch_pop(&mut task_batch, &mut batch_len); + let mut batch_len = 0; - if batch_len == 0 { - if self.task_queue.is_empty() { + while let Some(id) = self.task_queue.pop() { + task_batch[batch_len] = id; + batch_len += 1; + if batch_len == task_batch.len() { break; - } else { - continue; } } - for &id in &task_batch[..batch_len] { - if let Some(task) = self.tasks.get_mut(id) { - let waker = task - .waker - .get_or_insert_with(|| TaskWaker::new(id, Arc::clone(&self.task_queue))); + if batch_len == 0 { + break; + } - let waker = unsafe { Waker::from_raw(TaskWaker::into_raw_waker(waker)) }; - let mut cx = Context::from_waker(&waker); + for &(mut id) in &task_batch[..batch_len] { + if let Some(task) = self.tasks.get_mut(id) { + if task.is_paused() { + continue; + } + + let waker = create_waker(id, Arc::clone(&self.task_queue)); + let mut cx = ContextBuilder::from_waker(&waker).ext(&mut id).build(); if let Poll::Ready(()) = task.poll(&mut cx) { self.tasks.remove(id); - self.task_queue.free_tasks.push(id); } } } @@ -84,95 +101,70 @@ impl Executor { } struct Task { - future: Pin + Send>>, - waker: Option, + future: Pin>, + paused: AtomicBool, } impl Task { - #[inline(always)] - pub fn new(future: Pin + Send>>) -> Self { + fn new(future: Pin>) -> Self { Self { future, - waker: None, + paused: AtomicBool::new(false), } } - #[inline(always)] fn poll(&mut self, cx: &mut Context) -> Poll<()> { self.future.as_mut().poll(cx) } + + fn is_paused(&self) -> bool { + self.paused.load(Ordering::Acquire) + } + + fn set_paused(&self, paused: bool) { + self.paused.store(paused, Ordering::Release) + } } +fn create_waker(task_id: usize, task_queue: Arc>) -> Waker { + let data = Box::new(TaskWaker { + task_id, + task_queue, + }); + let raw_waker = RawWaker::new(Box::into_raw(data) as *const (), &VTABLE); + unsafe { Waker::from_raw(raw_waker) } +} + +#[derive(Clone)] struct TaskWaker { - id: usize, - task_queue: Arc, + task_id: usize, + task_queue: Arc>, } impl TaskWaker { - #[inline(always)] - fn new(id: usize, task_queue: Arc) -> Self { - Self { id, task_queue } - } - - #[inline(always)] fn wake(&self) { - self.task_queue.queue.push(self.id); - } - - fn into_raw_waker(waker: &TaskWaker) -> RawWaker { - let ptr = waker as *const TaskWaker; - RawWaker::new(ptr.cast(), &VTABLE) + self.task_queue.push(self.task_id); } } const VTABLE: RawWakerVTable = RawWakerVTable::new(clone_raw, wake_raw, wake_by_ref_raw, drop_raw); unsafe fn clone_raw(ptr: *const ()) -> RawWaker { - let waker = &*(ptr as *const TaskWaker); - TaskWaker::into_raw_waker(waker) + let task_waker = Box::from_raw(ptr as *mut TaskWaker); + let raw_waker = RawWaker::new(Box::into_raw(task_waker.clone()) as *const (), &VTABLE); + raw_waker } unsafe fn wake_raw(ptr: *const ()) { - let waker = &*(ptr as *const TaskWaker); - waker.wake(); + let task_waker = Box::from_raw(ptr as *mut TaskWaker); + task_waker.wake(); } unsafe fn wake_by_ref_raw(ptr: *const ()) { - let waker = &*(ptr as *const TaskWaker); - waker.wake(); + let task_waker = &*(ptr as *const TaskWaker); + task_waker.wake(); } -unsafe fn drop_raw(_: *const ()) {} - -struct TaskQueue { - queue: SegQueue, - next_task: usize, - free_tasks: SegQueue, -} - -impl TaskQueue { - fn new() -> Self { - Self { - queue: SegQueue::new(), - next_task: 0, - free_tasks: SegQueue::new(), - } - } - - #[inline(always)] - fn batch_pop(&self, output: &mut [usize], len: &mut usize) { - *len = 0; - while let Some(id) = self.queue.pop() { - output[*len] = id; - *len += 1; - if *len == output.len() { - break; - } - } - } - - #[inline(always)] - fn is_empty(&self) -> bool { - self.queue.is_empty() - } +unsafe fn drop_raw(ptr: *const ()) { + drop(Box::from_raw(ptr as *mut TaskWaker)); }