Hardware Interrupt Escalation Path Adaptation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional data processing systems face inefficiencies in handling interrupts due to the need for software-based redirecting of interrupts, which consumes instruction cycles and increases system bus traffic, especially when the number of outstanding interrupts exceeds the capacity of interrupt presentation controllers.

Innovation Solution

The implementation of hardware-based interrupt escalation paths in data processing systems, where an interrupt controller adapts the escalation path by determining the virtual processor thread and updating the event assignment data structure to route escalations to appropriate event notification descriptors, eliminating the need for software-based redirecting and reject messages.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If software-based interrupt redirecting is used, then interrupt handling flexibility is maintained, but system bus traffic increases and instruction cycles are consumed

Engineering Contradiction:

Improveinterrupt handling flexibilityVSAvoidsystem bus traffic

Core Design Contradiction:

Adaptability or versatilityVSLoss of energy

Solution Approach 1:

The patent replaces software-based interrupt redirecting mechanisms with a hardware-based escalation path mechanism. The interrupt controller hardware directly adapts escalation paths by determining virtual processor threads and updating event assignment data structures, eliminating the need for software intervention and reducing bus traffic while maintaining interrupt handling flexibility.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces an intermediary hardware mechanism (interrupt controller with event assignment data structure) that mediates between interrupt sources and virtual processor threads. This intermediary handles the adaptation of escalation paths in hardware, reducing the burden on software and minimizing system bus traffic.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Adaptability or versatility

If software-based interrupt redirecting is used, then interrupt handling flexibility is maintained, but instruction cycles are consumed

Engineering Contradiction:

Improveinterrupt handling flexibilityVSAvoidinstruction cycles

Core Design Contradiction:

Adaptability or versatilityVSLoss of time

Solution Approach 1:

The patent replaces software-based interrupt redirecting with hardware-based escalation path adaptation. The interrupt controller hardware directly determines virtual processor threads and updates event assignment data structures, eliminating software instruction cycles while maintaining interrupt handling flexibility.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent implements preliminary action by pre-configuring event assignment data structures and escalation paths in hardware. This allows the system to quickly adapt interrupt routing without requiring software intervention or instruction cycles, as the hardware is already prepared to handle escalation scenarios.

Inventive Principle:

Principle #10Preliminary action

3Reliability

If conventional interrupt handling is used, then system compatibility is maintained, but scalability is limited when outstanding interrupts exceed controller capacity

Engineering Contradiction:

Improvesystem compatibilityVSAvoidinterrupt capacity scalability

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent implements dynamics by making the escalation path adaptive rather than fixed. The interrupt controller dynamically determines virtual processor threads and updates event assignment data structures based on current system state, allowing the system to scale beyond conventional fixed capacity limits while maintaining compatibility through standardized hardware mechanisms.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS11561819B2Techniques for adapting escalation paths of interrupts in a data processing system

Publication Date: 2023.01.24 INTERNATIONAL BUSINESS MACHINE CORPORATION

AI summary

Techniques of adapting an interrupt escalation path are implemented in hardware. An interrupt controller receives, from a physical thread of the processor core, a request to adapt, in an event assignment data structure, an escalation path for a specified event source, where the escalation path includes a pointer to a first event notification descriptor. The interrupt controller reads an entry for the physical thread in an interrupt context data structure to determine a virtual processor thread running on the physical thread. Based on the virtual processor thread determined from the interrupt context data structure, the interrupt controller accesses an entry in a virtual processor data structure to determine a different second event notification descriptor to which escalations are to be routed. The interrupt controller updates the pointer in the event assignment data structure to identify the second event notification descriptor, such that the interrupt escalation path is adapted.