×

Efficient coherency response mechanism

  • US 9,632,933 B2
  • Filed: 02/03/2015
  • Issued: 04/25/2017
  • Est. Priority Date: 02/03/2015
  • Status: Active Grant
First Claim
Patent Images

1. A data processing system, comprising:

  • a plurality of processing units interconnected by a coherency network in accordance with a directed spanning tree in which the plurality of processing units comprises a first processing unit characterized as a root of the directed spanning tree, a first set of processing units each characterized as a leaf of the directed spanning tree, and a remaining set of processing units, exclusive of the first processing unit and first set of processing units, whereineach processing unit of the first set comprises;

    processing circuitry configured to provide a coherency response in response to a snoop request, andeach processing unit of the remaining set comprises;

    switch point circuitry comprising;

    one or more ingress ports coupled to neighboring processing units in accordance with the directed spanning tree,a coherency tracking table configured to store a combined coherency response in response to a particular snoop request based on one or more coherency responses received at the one or more ingress ports from the neighboring processing units,an egress port toward the first processing unit characterized as the root of the directed spanning tree, wherein the egress port is coupled to the coherency network, andcoherency logic configured to provide the combined coherency response for the particular snoop request on the egress port when a corresponding coherency response for the particular snoop request has been received from every one of the neighboring processing units in accordance with the directed spanning tree.

View all claims
  • 15 Assignments
Timeline View
Assignment View
    ×
    ×