Ex Parte Golla

Board of Patent Appeals and Interferences

Sep 16, 2010

10881247 (B.P.A.I. Sep. 16, 2010)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte ROBERT T. GOLLA
____________

Appeal 2009-006153
Application 10/881,247
Technology Center 2100
____________

Before JOSEPH L. DIXON, JAY P. LUCAS, and STEPHEN C. SIU,
Administrative Patent Judges.

DIXON, Administrative Patent Judge.

DECISION ON APPEAL1

1 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 C.F.R. § 1.304, or for filing a request for rehearing,
as recited in 37 C.F.R. § 41.52, begins to run from the “MAIL DATE”
(paper delivery mode) or the “NOTIFICATION DATE” (electronic delivery
mode) shown on the PTOL-90A cover letter attached to this decision.

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The Appellant appeals under 35 U.S.C. § 134(a) from the Final
rejection of claims 1-26, 28-37, and 39-42. Claims 27 and 38 have been
canceled. We have jurisdiction under 35 U.S.C. § 6(b).
We REVERSE.

I. STATEMENT OF THE CASE
The Invention
The invention at issue on appeal relates to a method and a device for
thread scheduling and selecting in a multi-thread processor (Spec. 1).

The Illustrative Claim
Claim 1, an illustrative claim, reads as follows:
1. A multithreaded processor, comprising:

a plurality of buffers, each configured to store a plurality of
instructions corresponding to a respective thread; and

a pick unit coupled to the plurality of buffers and configured to
pick from at least one of the plurality of buffers in a given cycle,
a valid instruction based upon a thread selection algorithm;

wherein the pick unit is further configured to cancel, in the
given cycle, the picking of the valid instruction in response to
receiving a cancel indication.

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The References
The Examiner relies on the following references as evidence:
Franke US 6,243,788 B1 Jun. 5, 2001
Parady US 2002/0091915 A1 Jul. 11, 2002
Emer US 6,470,443 B1 Oct. 22, 2002
Burns US 6,651,158 B2 Nov. 18, 2003
Davis US 6,931,641 B1 Aug. 16, 2005
Nguyen US 7,000,047 B2 Feb. 14, 2006

Hennessy and Patterson Computer Architecture: A Quantitative
Approach 3rd Edition 2003 (hereafter Hennessy)2

The Rejections
The following rejections are before us for review:
Claims 1, 11, and 21 stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over the combination of Burns and Paraday.
Claims 2, 3, 6, 7, 12, 13, 16, and 17 stand rejected under 35
U.S.C. § 103(a) as being unpatentable over the combination of Burns
Paraday, and Davis.
Claims 9 and 19 stand rejected under 35 U.S.C. § 103(a) as being
unpatentable over the combination of Burns, Nguyen and Paraday.
Claims 10 and 20 stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over the combination of Burns, Franke and Paraday.
Claims 4, 5, 8, 14, 15, and 18 stand rejected under 35 U.S.C. §

2 The reference was not cited in the Final Rejection, but was cited as
extrinsic evidence (Ans. 22).
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103(a) as being unpatentable over the combination of Burns, Paraday,
Davis, and Emer.
Claims 22 and 33 stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over the combination of Burns, Emer and Paraday.
Claims 23-26, 28-30, 34-37, and 39-40 stand rejected under 35
U.S.C. § 103(a) as being unpatentable over the combination of Burns,
Emer, Davis and Paraday.
Claims 31 and 41 stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over the combination of Burns, Emer, Nguyen and
Paraday.
Claims 32 and 42 stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over the combination of Burns, Emer, Paraday and
Franke.

II. ISSUE
Has the Examiner erred in finding that the combination of Burns and
Paraday teaches or fairly suggests “the pick unit is further configured to
cancel, in the given cycle, the picking of the valid instruction in response to
receiving a cancel indication”, as recited in independent claim 1?

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III. PRINCIPLES OF LAW
Obviousness
“Obviousness is a question of law based on underlying findings of
fact.” In re Kubin, 561 F.3d 1351, 1355 (Fed. Cir. 2009). The underlying
factual inquiries are: (1) the scope and content of the prior art, (2) the
differences between the prior art and the claims at issue, (3) the level of
ordinary skill in the pertinent art, and (4) secondary considerations of
nonobviousness. KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 406 (2007)
(citation omitted).

IV. FINDINGS OF FACT
The following findings of fact (FFs) are supported by a preponderance
of the evidence.
Paraday
1. Paraday discloses an embodiment of dependency checking circuitry to
detect the dependencies among the instructions:
In one embodiment, each thread unit supports out of order
execution of instructions. Dependency checking circuitry 770
may be configured to detect dependencies among instructions
within a single thread unit. In addition, dependency checking
circuitry may be configured to communicate dependency
information with other thread units. In one embodiment,
instructions may issue from multiple thread units in a single
clock cycle. For example, main thread unit 110A may issue all
possible instructions free of data dependencies on a clock cycle
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and if any functional units remain available, a next thread unit
may issue any non-dependent instructions in the same clock
cycle. Consequently, main thread unit 110A, upon which a
second thread may have data dependencies, may have priority
in the use of the processor's resources and processor resources
which may otherwise be idle may be more fully utilized.
Handling of data dependencies may be accomplished in a
number of well known ways. In a first embodiment, instructions
in all currently active thread units may be checked against one
another for dependencies. If an instruction is free of
dependencies it may issue. Alternatively, instructions may be
checked for dependencies within a single thread unit. Various
mechanisms may be employed in the checking of dependencies.
For example, dependency checking circuitry 770 may include
additional comparison circuitry or a future file for dependency
checking and resolution. In addition, dependency checking
circuitry may employ mechanisms to support out-of-order issue
and execution of instructions such as a reorder buffer.
([0069]) (Emphases added).
V. ANALYSIS
The Appellant has the opportunity on appeal to the Board of Patent
Appeals and Interferences (BPAI) to demonstrate error in the Examiner’s
position. See In re Kahn, 441 F.3d 977, 985-86 (Fed. Cir. 2006) (citing In re
Rouffet, 149 F.3d 1350, 1355 (Fed. Cir. 1998)).
The Examiner sets forth a detailed explanation of a reasoned
conclusion of unpatentability in the Examiner’s Answer. Therefore, we look
to the Appellant’s Brief to show error in the proffered reasoned conclusion.
Id.
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The Common Feature in Claims
Independent claim 1, recites, inter alia, “the pick unit is further
configured to cancel, in the given cycle, the picking of the valid instruction
in response to receiving a cancel indication”. Independent claims 11, 21, 22,
and 33 contain these similar limitations.
35 U.S.C. § 103(a) rejections
With respect to independent claim 1, the Appellant contends that
neither Burns nor Paraday discloses the disputed limitation (App. Br. 8).
According to the Appellant, “Paraday does not teach what happens to
instructions that do have dependencies, much less if they are picked and then
cancelled in the same cycle.” (Id.), and “there has to be an instruction that is
picked for there to be a cancel of the pick operation.” (Id.).
We agree with the Appellant’s contentions. First, we find the
Examiner admitted that Burns does not teach the cancelling operation (Ans.
3). Furthermore, we find that the paragraph of the Paraday reference relied
upon by the Examiner only discusses checking the dependencies among the
instructions within one thread or among other threads (FF 1). However, we
do not find Paraday teaches how to handle the instructions with
dependencies except mentions there were a number of ways to handle the
instruction dependencies (FF 1). In addition, we find Paraday does not even
mention a cancelling operation, let alone cancelling the picking of an
instruction in response to receiving a cancel indication. Finally, we find the
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Examiner’s argument that “an instruction with a data dependency will still
not be allowed to issue and will stall, resulting in a situation that reads upon
the claimed limitation” (Ans. 23) is not persuasive because the picked and
stalled instructions may not be canceled and there are a number of ways to
treat them in the queue such as reordering the instructions to resolve the
dependency, which is not in response to receiving a cancel indication as
claimed.
Because we agree with at least one of the Appellant’s contentions, we
find that the Examiner has not made a requisite showing of obviousness as
required to teach or fairly suggest the invention as recited in claim 1 by the
combined of Burns and Paraday. The rejection of the dependent claims 2-10
contains the same deficiency. The Appellant, thus, has demonstrated error
in the Examiner’s reasoned conclusion of obviousness of the subject matter
of claims 1-10.
The independent claims 11, 21, 22, and 33 contain the similar
limitations to those found in independent claim 1. The Appellant presents
similar arguments as set forth with respect to independent claim 1 in
response to the rejections of independent claims 11, 21, 22, and 33 (App. Br.
9 and 12).
As we found above in our discussion with respect to independent
claim 1, we similarly find that the Appellant has demonstrated error in the
Examiner’s conclusion for obviousness of the subject matter of independent
claims 11, 21, 22, and 33. The rejection of dependent claims 12-20, 23-26,
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28-32, 34-37, and 39-42 also contains the same deficiency. Hence, the
Appellant’s argument persuades us that the Examiner erred in rejecting
claims 1-26, 28-37, and 39-42.
We, therefore, cannot sustain the rejection of claims 1-26, 28-37, and
39-42 under 35 U.S.C. § 103.

VI. CONCLUSION
We conclude that the Examiner has erred in finding that the
combination of Burns and Paraday teaches or fairly suggests “the pick unit is
further configured to cancel, in the given cycle, the picking of the valid
instruction in response to receiving a cancel indication”, as recited in
independent claim 1.

VII. ORDER
We reverse the obviousness rejections of claims 1-26, 28-37, and 39-
42 under 35 U.S.C. § 103(a).

REVERSED

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