Interrupt Handling Circuitry for Bounded Memory Access
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In real-time applications, certain memory access operations with unbounded completion times pose challenges for handling interrupts within a bounded period, as they can change data contents and require responses, making it difficult to abort or stall such operations without causing data inconsistencies or prolonging interrupt handling times.
Innovation Solution
The implementation of memory access operation handling circuitry that determines whether the remaining time to complete a memory access operation is bounded, stalling interrupts if bounded and aborting the operation if unbounded, to ensure interrupt handling within a bounded time frame while managing data integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the memory access operation is allowed to complete before handling the interrupt, then data consistency is maintained, but the interrupt handling time becomes unbounded
Solution Approach 1:
The patent applies dynamics by making the interrupt handling behavior adaptive based on the memory access operation state. The system dynamically determines whether to stall or abort the memory access operation based on whether the remaining time is bounded, allowing flexible response to different operational states rather than using a fixed approach
Solution Approach 2:
The patent changes the parameter of memory access operation handling from a static approach to a dynamic one by introducing the concept of checking whether remaining time is bounded. This parameter change enables the system to switch between different handling modes (stall vs abort) based on the temporal characteristics of the memory operation
2Loss of time
If the memory access operation is aborted to allow timely interrupt handling, then interrupt response time is bounded, but data consistency may be compromised
Solution Approach 1:
The patent implements feedback by having the memory access operation handling circuitry continuously monitor the state of the memory access operation and determine whether the remaining time is bounded. This feedback mechanism allows the system to make informed decisions about whether to stall or abort based on real-time operational status
Solution Approach 2:
The patent applies preliminary action by determining the boundedness of remaining time before actually stalling or aborting the memory access operation. This advance assessment allows the system to prepare the appropriate handling strategy in advance, ensuring both data consistency and timely interrupt response
3Reliability
If the interrupt is stalled until the memory access operation completes, then data consistency is ensured, but the interrupt handling is delayed beyond bounded time
Solution Approach 1:
The system dynamically adjusts interrupt handling behavior based on the memory access operation state, switching between stalling and aborting modes. This dynamic approach optimizes interrupt handling throughput by avoiding unnecessary stalls when the remaining time is unbounded
Solution Approach 2:
The patent changes the handling parameter from always-stall to conditional-based-on-time-boundedness, enabling the system to abort operations when stalling would cause unbounded delays. This parameter change directly improves interrupt handling throughput while maintaining data consistency when possible
4Loss of time
If the memory access operation is aborted, then interrupt response time is bounded, but the complexity of managing data integrity increases
Solution Approach 1:
The patent introduces memory access operation handling circuitry as an intermediary between the processing circuitry and the memory system. This intermediary component manages the complexity of data integrity by automatically determining whether to stall or abort operations, shielding the main processing system from the complexity of interrupt timing constraints
Data Source
AI summary
An apparatus has processing circuitry and a memory system. The memory system is responsive to a first type of memory access operation for which a time taken to handle the memory access operation is unbounded, the operation is able to change contents of data stored in the memory system, and a response is required. The apparatus has memory access operation handling circuitry that receives an indication of an interrupt to be taken while a memory access operation of the first type is being handled by the memory system and determines whether the memory access operation has reached a stage for which a remaining time to complete the memory access operation will be bounded. In dependence on the remaining time, the memory access operation handling circuitry either stalls the interrupt until the memory access operation has completed or aborts the memory access operation and allow the interrupt to be taken.