From 60acc2e58daa9de37f59c2dfbe121c3efc1f4643 Mon Sep 17 00:00:00 2001
From: EDiasAlberto <proxamon1@gmail.com>
Date: Thu, 24 Oct 2024 21:46:39 +0100
Subject: [PATCH] refactor thread_mlfqs checks in synch.c

---
 src/threads/synch.c  | 77 +++++++++++++++++++++-----------------------
 src/threads/thread.c | 32 ++++++++++--------
 2 files changed, 55 insertions(+), 54 deletions(-)

diff --git a/src/threads/synch.c b/src/threads/synch.c
index 0ceb746..3fe957c 100644
--- a/src/threads/synch.c
+++ b/src/threads/synch.c
@@ -305,53 +305,50 @@ lock_release (struct lock *lock)
   ASSERT (lock != NULL);
   ASSERT (lock_held_by_current_thread (lock));
 
-  if (!thread_mlfqs)
-  {
-    struct thread *current_thread = thread_current ();
-    struct thread *max_donor = NULL;
+  struct thread *current_thread = thread_current ();
+  struct thread *max_donor = NULL;
 
-    struct list orphan_list;
-    list_init (&orphan_list);
+  struct list orphan_list;
+  list_init (&orphan_list);
 
-    enum intr_level old_level = intr_disable ();
-    /* Loop through current thread's donors, removing the ones waiting for the
-       lock being released and keeping track of them (within orphan_list).
-       Also identifies the highest priority donor thread among them. */
-    struct list_elem *tail = list_tail (&current_thread->donors_list);
-    struct list_elem *e = list_begin (&current_thread->donors_list);
-    while (e != tail)
-      {
-        struct thread *donor = list_entry (e, struct thread, donor_elem);
-        struct list_elem *next = list_next (e);
+  enum intr_level old_level = intr_disable ();
+  /* Loop through current thread's donors, removing the ones waiting for the
+     lock being released and keeping track of them (within orphan_list).
+     Also identifies the highest priority donor thread among them. */
+  struct list_elem *tail = list_tail (&current_thread->donors_list);
+  struct list_elem *e = list_begin (&current_thread->donors_list);
+  while (e != tail)
+    {
+      struct thread *donor = list_entry (e, struct thread, donor_elem);
+      struct list_elem *next = list_next (e);
 
-        /* Excludes donors that aren't waiting for the lock being released,
-           and tracks the rest. */
-        if (donor->waiting_lock == lock)
-          {
-            list_remove (e);
-            list_push_back (&orphan_list, e);
+      /* Excludes donors that aren't waiting for the lock being released,
+         and tracks the rest. */
+      if (donor->waiting_lock == lock)
+        {
+          list_remove (e);
+          list_push_back (&orphan_list, e);
 
-            /* Identify highest priority donor. */
-            if (max_donor == NULL || donor->priority > max_donor->priority)
-              max_donor = donor;
-          }
+          /* Identify highest priority donor. */
+          if (max_donor == NULL || donor->priority > max_donor->priority)
+            max_donor = donor;
+        }
 
-        e = next;
-      }
+      e = next;
+    }
 
-    /* If there exists a maximum donor thread waiting for this lock to be
-       released, transfer the remaining orphaned donors to its donor list. */
-    if (max_donor != NULL)
-      {
-        while (!list_empty (&orphan_list))
-          list_push_back (&max_donor->donors_list, list_pop_front (&orphan_list));
-      }
+  /* If there exists a maximum donor thread waiting for this lock to be
+     released, transfer the remaining orphaned donors to its donor list. */
+  if (max_donor != NULL)
+    {
+      while (!list_empty (&orphan_list))
+        list_push_back (&max_donor->donors_list, list_pop_front (&orphan_list));
+    }
 
-    intr_set_level (old_level);
-    /* Removal of donors to this thread may change its effective priority,
-       so recalculate. */
-    thread_recalculate_priority ();
-  }
+  intr_set_level (old_level);
+  /* Removal of donors to this thread may change its effective priority,
+     so recalculate. */
+  thread_recalculate_priority ();
 
   lock->holder = NULL;
   sema_up (&lock->semaphore);
diff --git a/src/threads/thread.c b/src/threads/thread.c
index 4afbe68..795866e 100644
--- a/src/threads/thread.c
+++ b/src/threads/thread.c
@@ -157,23 +157,26 @@ thread_tick (void)
 
   /* Update system load_avg and all threads recent_cpu every second. */
   int64_t ticks = timer_ticks ();
-  if (thread_mlfqs && (ticks % TIMER_FREQ == 0))
+  if (thread_mlfqs)
     {
-      size_t ready = threads_ready ();
       if (t != idle_thread)
-        ready++;
-      fp32_t old_coeff = fp_div_int (fp_mul_int(load_avg, 59), 60);
-      fp32_t new_coeff = fp_div_int (fp_from_int (ready), 60);
-      load_avg = fp_add (old_coeff, new_coeff);
+        {
+          t->recent_cpu = fp_add_int (t->recent_cpu, 1);
+        }
 
-      thread_foreach (thread_update_recent_cpu, NULL);
-    }
+      if (ticks % TIMER_FREQ == 0)
+        {
+          size_t ready = threads_ready ();
+          if (t != idle_thread)
+            ready++;
+          fp32_t old_coeff = fp_div_int (fp_mul_int(load_avg, 59), 60);
+          fp32_t new_coeff = fp_div_int (fp_from_int (ready), 60);
+          load_avg = fp_add (old_coeff, new_coeff);
 
-  /* Update current thread's recent_cpu. */
-  if (thread_mlfqs && (t != idle_thread))
-    {
-      t->recent_cpu = fp_add_int (t->recent_cpu, 1);
-      if (ticks % 4 == 0) // recent_cpu was updated, update priority.
+          thread_foreach (thread_update_recent_cpu, NULL);
+        }
+
+      if (ticks % TIME_SLICE == 0) // recent_cpu was updated, update priority.
         t->priority = calculate_bsd_priority (t->recent_cpu, t->nice);
     }
 
@@ -470,7 +473,8 @@ thread_recalculate_priority (void)
 {
   struct thread *t = thread_current ();
 
-  ASSERT(!thread_mlfqs)
+  if (thread_mlfqs)
+    return;
 
   enum intr_level old_level = intr_disable ();
   t->priority = t->base_priority;