Point-to-point interrupt messaging within a multiprocessing computer system

In a multiprocessing computer system including:

• an I/O subsystem,
• an I/O bridge coupled to said I/O subsystem, and
• a plurality of processing nodes, wherein a first processing node of said plurality of processing nodes is coupled to said I/O bridge through a first interconnect structure, and wherein said plurality of processing nodes is interconnected through a second interconnect structure,
• a method for servicing an interrupt within said multiprocessing computer system,
• said method comprising:
• said I/O bridge receiving an interrupt request from said I/O subsystem;
• said I/O bridge generating a first interrupt packet in response to said receiving said interrupt request;
• said I/O bridge transmitting said first interrupt packet to said first processing node through said first interconnect structure;
• said first processing node receiving said first interrupt packet and generating a second interrupt packet therefrom;
• and
• said first processing node delivering through said second interconnect structure said second interrupt packet to each remaining processing node of said plurality of processing nodes regardless of whether said first interrupt packet identifies said each remaining processing node as a target of said interrupt request.

In a multiprocessing computer system including:

• an I/O subsystem,
• an I/O bridge coupled to said I/O subsystem, and
• a plurality of processing nodes, wherein a first processing node of said plurality of processing nodes is coupled to said I/O bridge through a first interconnect structure, and wherein said plurality of processing nodes is interconnected through a second interconnect structure,
• a method for servicing an interrupt within said multiprocessing computer system,
• said method comprising:
• said I/O bridge receiving an interrupt request from said I/O subsystem;
• said I/O bridge generating an interrupt packet in response to said receiving said interrupt request;
• said I/O bridge transmitting said interrupt packet to said first processing node over said first interconnect structure;
• and
• said first processing node delivering through said second interconnect structure said interrupt packet to each remaining processing node of said plurality of processing nodes regardless of whether said interrupt packet identifies said each remaining processing node as a target of said interrupt request.