1 files changed, 0 insertions, 144 deletions
diff --git a/kernel/waitqueue.cc b/kernel/waitqueue.cc
deleted file mode 100644
index 9689417..0000000
--- a/kernel/waitqueue.cc
+++ /dev/null
@@ -1,144 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/* Copyright (C) 2026 Richard Qin */
-
-/*
- * WaitQueue — blocking synchronization implementation
- *
- * Two-phase wait protocol:
- *
- *   prepare_to_wait():  task → Sleeping, link into queue
- *   [caller checks condition — if still false, calls schedule()]
- *   finish_wait():      remove from queue, restore Runnable
- *
- * Legacy sleep() wraps the two-phase pattern for simple callers.
- *
- * wake_one()/wake_all(): dequeue waiters → Runnable, sched_enqueue()
- *
- * The internal spinlock protects the wait list only.
- * schedule() is called AFTER releasing all spinlocks to avoid
- * holding a lock across a context switch.
- */
-
-#include <lume/waitqueue.h>
-#include <lume/task.h>
-#include <lume/sched.h>
-#include <lume/kprintf.h>
-#include <arch/cpu.h>
-
-/* ------------------------------------------------------------------ */
-/*  Two-phase wait API                                                 */
-/* ------------------------------------------------------------------ */
-
-void WaitQueue::prepare_to_wait(TaskControlBlock* task, TaskState new_state)
-{
-    LockGuard guard(lock_);
-
-    /* Set state BEFORE linking — this is the key to preventing lost wakeups.
-     * If wake_one fires between now and schedule(), it will set state back
-     * to Runnable, and schedule() will see Runnable and not block. */
-    task->state = new_state;
-
-    /* Only add to queue if not already linked (idempotent) */
-    if (task->run_link.next == &task->run_link) {
-        /* Link into wait queue tail */
-        list_node* node = &task->run_link;
-        node->prev = head_.prev;
-        node->next = &head_;
-        head_.prev->next = node;
-        head_.prev = node;
-    }
-}
-
-void WaitQueue::finish_wait(TaskControlBlock* task)
-{
-    LockGuard guard(lock_);
-
-    /* Remove from wait queue if still linked */
-    if (task->run_link.next != &task->run_link) {
-        list_node* node = &task->run_link;
-        node->prev->next = node->next;
-        node->next->prev = node->prev;
-        node->init();
-    }
-
-    /* Ensure task is Runnable (it may have been woken by wake_one/wake_all
-     * already, or it may never have slept if the condition was true). */
-    if (task->state == TaskState::Sleeping) {
-        task->state = TaskState::Runnable;
-    }
-}
-
-/* ------------------------------------------------------------------ */
-/*  Legacy convenience API                                             */
-/* ------------------------------------------------------------------ */
-
-void WaitQueue::sleep(Spinlock* external_lock)
-{
-    TaskControlBlock* curr = current_task();
-    if (!curr) {
-        if (external_lock) external_lock->release();
-        return;
-    }
-
-    /* Phase 1: add to queue, mark Sleeping */
-    prepare_to_wait(curr, TaskState::Sleeping);
-
-    /* Release external lock AFTER we are on the queue (critical ordering) */
-    if (external_lock) {
-        external_lock->release();
-    }
-
-    /* Phase 2: context switch away — will return here when woken */
-    schedule();
-
-    /* Phase 3: clean up */
-    finish_wait(curr);
-}
-
-/* ------------------------------------------------------------------ */
-/*  Wakeup                                                             */
-/* ------------------------------------------------------------------ */
-
-bool WaitQueue::wake_one()
-{
-    LockGuard guard(lock_);
-
-    if (head_.is_empty())
-        return false;
-
-    /* Dequeue the first (oldest) waiter */
-    list_node* node = head_.next;
-    node->prev->next = node->next;
-    node->next->prev = node->prev;
-    node->init();
-
-    TaskControlBlock* task =
-        list_entry<TaskControlBlock, &TaskControlBlock::run_link>(node);
-
-    task->state = TaskState::Runnable;
-    sched_enqueue(task);
-
-    return true;
-}
-
-int WaitQueue::wake_all()
-{
-    LockGuard guard(lock_);
-
-    int count = 0;
-    while (!head_.is_empty()) {
-        list_node* node = head_.next;
-        node->prev->next = node->next;
-        node->next->prev = node->prev;
-        node->init();
-
-        TaskControlBlock* task =
-            list_entry<TaskControlBlock, &TaskControlBlock::run_link>(node);
-
-        task->state = TaskState::Runnable;
-        sched_enqueue(task);
-        count++;
-    }
-
-    return count;
-}