basic implementation of most functions. not tested, but generally well thought out

1 files changed, 70 insertions, 7 deletions

diff --git a/kernel/proc/sched.c b/kernel/proc/sched.c
index 3bc20c8..2e69634 100644
--- a/kernel/proc/sched.c
+++ b/kernel/proc/sched.c
@@ -162,7 +162,16 @@ void sched_init(void)
  */
 long sched_cancellable_sleep_on(ktqueue_t *queue)
 {
-    NOT_YET_IMPLEMENTED("PROCS: sched_cancellable_sleep_on");
+    // NOT_YET_IMPLEMENTED("PROCS: sched_cancellable_sleep_on");
+
+    KASSERT(queue != NULL);
+
+    curthr->kt_state = KT_SLEEP_CANCELLABLE;
+
+    sched_switch(queue);
+
+    // TODO: finish this function - consider the ipl_wait() function
+
     return 0;
 }
 
@@ -174,7 +183,15 @@ long sched_cancellable_sleep_on(ktqueue_t *queue)
  */
 void sched_cancel(kthread_t *thr)
 {
-    NOT_YET_IMPLEMENTED("PROCS: sched_cancel");
+    // NOT_YET_IMPLEMENTED("PROCS: sched_cancel");
+
+    thr->kt_cancelled = 1;
+
+    if (thr->kt_state == KT_SLEEP_CANCELLABLE)
+    {
+        ktqueue_remove(thr->kt_wchan, thr);
+        sched_make_runnable(thr);
+    }
 }
 
 /*
@@ -210,7 +227,20 @@ void sched_cancel(kthread_t *thr)
  */
 void sched_switch(ktqueue_t *queue)
 {
-    NOT_YET_IMPLEMENTED("PROCS: sched_switch");
+    // NOT_YET_IMPLEMENTED("PROCS: sched_switch");
+
+    KASSERT(intr_getipl == IPL_HIGH);
+    intr_disable();
+
+    KASSERT(curthr->kt_state != KT_ON_CPU);
+
+    ktqueue_enqueue(queue, curthr);
+    curcore.kc_queue = queue;
+    last_thread_context = &curthr->kt_ctx;
+
+    intr_setipl(IPL_LOW); // allow interrupts to wake up the idling core
+    intr_enable();
+    context_switch(&curthr->kt_ctx, &curcore.kc_ctx);
 }
 
 /*
@@ -236,7 +266,15 @@ void sched_yield()
  */
 void sched_make_runnable(kthread_t *thr)
 {
-    NOT_YET_IMPLEMENTED("PROCS: sched_make_runnable");
+    // NOT_YET_IMPLEMENTED("PROCS: sched_make_runnable");
+
+    KASSERT(thr != curthr);
+    KASSERT(thr->kt_state != KT_RUNNABLE);
+
+    int oldIPL = intr_setipl(IPL_HIGH);
+    thr->kt_state = KT_RUNNABLE;
+    ktqueue_enqueue(&kt_runq, thr);
+    intr_setipl(oldIPL);
 }
 
 /*
@@ -255,7 +293,13 @@ void sched_make_runnable(kthread_t *thr)
  */
 void sched_sleep_on(ktqueue_t *q)
 {
-    NOT_YET_IMPLEMENTED("PROCS: sched_sleep_on");
+    // NOT_YET_IMPLEMENTED("PROCS: sched_sleep_on");
+
+    int oldIPL = intr_setipl(IPL_HIGH);
+    curthr->kt_state = KT_SLEEP;
+
+    sched_switch(q);
+    // intr_setipl(oldIPL); not called, hold the lock into the sched_switch call
 }
 
 /*
@@ -271,7 +315,21 @@ void sched_sleep_on(ktqueue_t *q)
  */
 void sched_wakeup_on(ktqueue_t *q, kthread_t **ktp)
 {
-    NOT_YET_IMPLEMENTED("PROCS: sched_wakeup_on");
+    // NOT_YET_IMPLEMENTED("PROCS: sched_wakeup_on");
+
+    if (sched_queue_empty(q))
+    {
+        return;
+    }
+
+    int oldIPL = intr_setipl(IPL_HIGH); // don't allow interrupts while modifying the queue
+    kthread_t *thr = ktqueue_dequeue(q);
+    if (ktp)
+    {
+        *ktp = thr;
+    }
+    sched_make_runnable(thr);
+    intr_setipl(oldIPL);
 }
 
 /*
@@ -279,7 +337,12 @@ void sched_wakeup_on(ktqueue_t *q, kthread_t **ktp)
  */
 void sched_broadcast_on(ktqueue_t *q)
 {
-    NOT_YET_IMPLEMENTED("PROCS: sched_broadcast_on");
+    // NOT_YET_IMPLEMENTED("PROCS: sched_broadcast_on");
+
+    while (!sched_queue_empty(q))
+    {
+        sched_make_runnable(ktqueue_dequeue(q));
+    }
 }
 
 /*===============