+Index: src/devices/timer.c
diff -u src/devices/timer.c~ src/devices/timer.c
---- src/devices/timer.c~ 2005-05-24 15:52:43.000000000 -0700
-+++ src/devices/timer.c 2005-05-26 15:19:20.000000000 -0700
+--- src/devices/timer.c~
++++ src/devices/timer.c
@@ -23,6 +23,9 @@ static volatile int64_t ticks;
Initialized by timer_calibrate(). */
static unsigned loops_per_tick;
}
/* Calibrates loops_per_tick, used to implement brief delays. */
-@@ -87,15 +92,36 @@ timer_elapsed (int64_t then)
+@@ -93,16 +93,37 @@
return timer_ticks () - then;
}
+ return a->wakeup_time < b->wakeup_time;
+}
+
- /* Suspends execution for approximately TICKS timer ticks. */
+ /* Sleeps for approximately TICKS timer ticks. Interrupts must
+ be turned on. */
void
timer_sleep (int64_t ticks)
{
+ sema_down (&t->timer_sema);
}
- /* Suspends execution for approximately MS milliseconds. */
-@@ -132,6 +158,16 @@ timer_interrupt (struct intr_frame *args
+ /* Sleeps for approximately MS milliseconds. Interrupts must be
+@@ -132,6 +158,17 @@ timer_interrupt (struct intr_frame *args
{
ticks++;
thread_tick ();
+ if (ticks < t->wakeup_time)
+ break;
+ sema_up (&t->timer_sema);
++ thread_yield_to_higher_priority ();
+ list_pop_front (&wait_list);
+ }
}
/* Returns true if LOOPS iterations waits for more than one timer
+Index: src/threads/fixed-point.h
diff -u src/threads/fixed-point.h~ src/threads/fixed-point.h
---- src/threads/fixed-point.h~ 1969-12-31 16:00:00.000000000 -0800
-+++ src/threads/fixed-point.h 2005-06-02 14:11:21.000000000 -0700
+--- src/threads/fixed-point.h~
++++ src/threads/fixed-point.h
@@ -0,0 +1,120 @@
+#ifndef THREADS_FIXED_POINT_H
+#define THREADS_FIXED_POINT_H
+}
+
+#endif /* threads/fixed-point.h */
+Index: src/threads/synch.c
diff -u src/threads/synch.c~ src/threads/synch.c
---- src/threads/synch.c~ 2005-05-24 20:47:28.000000000 -0700
-+++ src/threads/synch.c 2005-06-02 14:20:15.000000000 -0700
+--- src/threads/synch.c~
++++ src/threads/synch.c
@@ -114,10 +114,28 @@ sema_up (struct semaphore *sema)
ASSERT (sema != NULL);
+ const struct semaphore_elem *b
+ = list_entry (b_, struct semaphore_elem, elem);
+
-+ return a->thread->priority > b->thread->priority;
++ return a->thread->priority < b->thread->priority;
+}
+
/* If any threads are waiting on COND (protected by LOCK), then
}
/* Wakes up all threads, if any, waiting on COND (protected by
+Index: src/threads/thread.c
diff -u src/threads/thread.c~ src/threads/thread.c
---- src/threads/thread.c~ 2005-06-02 14:35:12.000000000 -0700
-+++ src/threads/thread.c 2005-06-02 14:55:56.000000000 -0700
+--- src/threads/thread.c~
++++ src/threads/thread.c
@@ -5,12 +5,14 @@
#include <stdio.h>
#include <string.h>
+#include "threads/init.h"
#include "threads/interrupt.h"
#include "threads/intr-stubs.h"
- #include "threads/mmu.h"
#include "threads/palloc.h"
#include "threads/switch.h"
#include "threads/synch.h"
+#include "devices/timer.h"
+ #include "threads/vaddr.h"
#ifdef USERPROG
#include "userprog/process.h"
#endif
- /* Enforce preemption. */
- if (++thread_ticks >= TIME_SLICE)
- intr_yield_on_return ();
-+ if (enable_mlfqs)
++ if (thread_mlfqs)
+ {
+ /* Update load average. */
+ if (timer_ticks () % TIMER_FREQ == 0)
+ /* Switch threads if time slice has expired. */
+ if (++thread_ticks >= TIME_SLICE)
+ {
-+ if (enable_mlfqs)
++ if (thread_mlfqs)
+ thread_recompute_priority (thread_current ());
+ intr_yield_on_return ();
+ }
/* Initialize thread. */
- init_thread (t, name, priority);
-+ init_thread (t, name, enable_mlfqs ? cur->priority : priority);
++ init_thread (t, name, thread_mlfqs ? cur->priority : priority);
tid = t->tid = allocate_tid ();
+ t->nice = cur->nice;
+ t->recent_cpu = cur->recent_cpu;
+
/* Add to run queue. */
thread_unblock (t);
-+ if (priority < thread_get_priority ())
++ if (priority > thread_get_priority ())
+ thread_yield ();
return tid;
+ const struct thread *a = list_entry (a_, struct thread, elem);
+ const struct thread *b = list_entry (b_, struct thread, elem);
+
-+ return a->priority > b->priority;
++ return a->priority < b->priority;
+}
+
/* Transitions a blocked thread T to the ready-to-run state.
+thread_set_priority (int priority)
{
- thread_current ()->priority = new_priority;
-+ if (!enable_mlfqs)
++ if (!thread_mlfqs)
+ {
+ struct thread *t = thread_current ();
+
}
/* Returns the current thread's priority. */
-@@ -298,33 +386,93 @@ thread_get_priority (void)
+@@ -298,33 +386,98 @@ thread_get_priority (void)
/* Sets the current thread's nice value to NICE. */
void
+ const struct thread *a = list_entry (a_, struct thread, donor_elem);
+ const struct thread *b = list_entry (b_, struct thread, donor_elem);
+
-+ return a->priority > b->priority;
++ return a->priority < b->priority;
+}
+
+/* Recomputes T's priority in terms of its normal priority and
+{
+ int old_priority = t->priority;
+ int default_priority = t->normal_priority;
-+ int donation = PRI_MAX;
-+ if (enable_mlfqs)
++ int donation = PRI_MIN;
++ if (thread_mlfqs)
+ {
-+ default_priority = fix_round (t->recent_cpu) / 4 + t->nice * 2;
++ default_priority = PRI_MAX - fix_round (t->recent_cpu) / 4 - t->nice * 2;
+ if (default_priority < PRI_MIN)
+ default_priority = PRI_MIN;
+ else if (default_priority > PRI_MAX)
+ if (!list_empty (&t->donors))
+ donation = list_entry (list_max (&t->donors, donated_lower_priority, NULL),
+ struct thread, donor_elem)->priority;
-+ t->priority = donation < default_priority ? donation : default_priority;
-+ if (t->priority < old_priority && t->donee != NULL)
++ t->priority = donation > default_priority ? donation : default_priority;
++ if (t->priority > old_priority && t->donee != NULL)
+ thread_recompute_priority (t->donee);
+}
+
+ struct thread *max = list_entry (list_max (&ready_list,
+ thread_lower_priority, NULL),
+ struct thread, elem);
-+ if (max->priority < cur->priority)
-+ thread_yield ();
++ if (max->priority > cur->priority)
++ {
++ if (intr_context ())
++ intr_yield_on_return ();
++ else
++ thread_yield ();
++ }
+ }
+ intr_set_level (old_level);
}
}
/* Completes a thread switch by activating the new thread's page
+Index: src/threads/thread.h
diff -u src/threads/thread.h~ src/threads/thread.h
---- src/threads/thread.h~ 2005-06-02 14:32:36.000000000 -0700
-+++ src/threads/thread.h 2005-06-02 14:38:46.000000000 -0700
+--- src/threads/thread.h~
++++ src/threads/thread.h
@@ -4,6 +4,8 @@
#include <debug.h>
#include <list.h>
+ /* Alarm clock. */
+ int64_t wakeup_time; /* Time to wake this thread up. */
-+ struct list_elem timer_elem; /* Element in timer_wait_list. */
++ struct list_elem timer_elem; /* Element in wait_list. */
+ struct semaphore timer_sema; /* Semaphore. */
+
#ifdef USERPROG
projects / pintos-anon / blobdiff