Rcore Gangs May 2026

/// Called when a task becomes runnable (e.g., wakes from I/O or is created) pub fn notify_task_ready(&mut self, tid: usize) if let Some(&gang_id) = self.task_to_gang.get(&tid) let gang = self.gangs.get(&gang_id).unwrap(); let mut gang_lock = gang.lock(); // Check if all members are now runnable let all_ready = gang_lock.members.iter().all(

pub fn create_gang(&mut self, members: Vec<usize>) -> usize let id = self.gangs.len(); let gang = Arc::new(Mutex::new(Gang id, members: members.clone(), status: GangStatus::Pending, )); for &tid in &members self.task_to_gang.insert(tid, id); self.gangs.insert(id, gang); id rcore gangs

fn next(&mut self) -> Option<Arc<TaskControlBlock>> if let Some(tid) = self.gang_sched.pick_next_task() return find_task_by_tid(tid); self.inner.next() /// Called when a task becomes runnable (e

impl Scheduler for HybridScheduler fn push(&mut self, task: Arc<TaskControlBlock>) if let Some(gang_id) = self.gang_sched.task_to_gang.get(&task.tid) self.gang_sched.notify_task_ready(task.tid); else self.inner.push(task); let mut gang_lock = gang.lock()

#[derive(PartialEq)] pub enum GangStatus Pending, // waiting for all members to be ready Runnable, // all ready, can schedule Running, // currently scheduled on CPUs

pub struct GangScheduler gangs: BTreeMap<usize, Arc<Mutex<Gang>>>, task_to_gang: BTreeMap<usize, usize>, ready_gangs: VecDeque<usize>, // queue of gang IDs ready to run

/// Pick the next runnable gang, then return its next member to run pub fn pick_next_task(&mut self) -> Option<usize> while let Some(gang_id) = self.ready_gangs.pop_front() let gang = self.gangs.get(&gang_id).unwrap(); let mut gang_lock = gang.lock(); if gang_lock.status == GangStatus::Runnable gang_lock.status = GangStatus::Running; // Return the first member that isn't already running on a CPU for &tid in &gang_lock.members if !is_task_running_on_another_cpu(tid) return Some(tid); // If all already running (rare), re-queue self.ready_gangs.push_back(gang_id); None