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Merge 'task1/priority-donation' into 'master' #14

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sb3923 merged 66 commits from task1/priority-donation into master 2024-10-23 16:15:45 +00:00
Conversation 35 Commits 66 Files Changed 4 +129 -10
4 changed files with 129 additions and 10 deletions
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13
src/threads/synch.c
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@@ -187,6 +187,9 @@ lock_init (struct lock *lock)
sema_init (&lock->semaphore, 1); sema_init (&lock->semaphore, 1);
} }
static void
donate_priority (struct thread *donor, struct thread *donee);
/* Acquires LOCK, sleeping until it becomes available if /* Acquires LOCK, sleeping until it becomes available if
necessary. The lock must not already be held by the current necessary. The lock must not already be held by the current
thread. thread.
@@ -202,8 +205,18 @@ lock_acquire (struct lock *lock)
ASSERT (!intr_context ()); ASSERT (!intr_context ());
ASSERT (!lock_held_by_current_thread (lock)); ASSERT (!lock_held_by_current_thread (lock));
struct thread *t = thread_current ();
/* TODO: If a high-priority thread holding a lock sleeps, this may cause a
race condition here or break the assumption that donation must occur. */
if (lock->holder != NULL)
{
t->waiting_lock = lock;
}
sema_down (&lock->semaphore); sema_down (&lock->semaphore);
lock->holder = thread_current (); lock->holder = thread_current ();
t->waiting_lock = NULL;
} }
/* Tries to acquires LOCK and returns true if successful or false /* Tries to acquires LOCK and returns true if successful or false