Appeal No. 2004-2187
Application No. 09/378,549
on an object and is unable to because it is already
locked by another thread currently using the object.
The first thread (attempting to obtain the lock) is
then enqueued on the object (i.e.[,] the thread will
wait or suspends itself until the second thread
releases the lock on the object). Also, any other
thread which attempts to lock the object will be
enqueued on the object such that the first thread will
gain access to the object before any other thread.
This is well known in the art and is known as a “queue
lock”. Therefore, the Bacon patent teaches indicating
the type of lock on an object (either an exclusive with
no waiting threads, or a queue lock).
Thus, the examiner is of the view that a change in the Bacon bit
indicates a change in the type of lock from an “exclusive with no
waiting threads” to a queue lock and that, therefore, the Bacon
bit indicates the type of lock.
The Bacon bit only indicates whether threads are waiting to
lock an object (e.g., the Bacon bit is 0 if there are no waiting
threads and 1 if there is a queue of waiting threads associated
with the object) (col. 3, lines 44-51; col. 5, lines 12-15
and 56-65). The examiner has not provided evidence that a lock
which has no waiting threads reasonably can be considered to
become a different type of lock when it has waiting threads, and
vice versa. Hence, the examiner has not established that the
Bacon bit represents or identifies the type of lock.
3
Page: Previous 1 2 3 4 5 Next
Last modified: November 3, 2007