Atomic Instruction Set for Interrupt-Free Bus Arbitration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing processor architectures face increased latency and overhead due to interrupts, particularly in embedded systems, which can disrupt program execution flow and introduce bugs, especially during operations like two-byte write operations to I/O devices.
Innovation Solution
An atomic instruction set and architecture with bus arbitration locking, where interrupts are selectively blocked and busses are locked during execution of designated instructions, allowing consecutive instructions to be executed atomically without mode switching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If interrupts are enabled in processor execution, then system responsiveness is improved, but execution latency and overhead increase
Solution Approach 1:
The patent segments interrupt handling into two distinct modes: supervisor mode for traditional interrupt processing and user mode for atomic operations. This segmentation allows critical atomic instruction sequences to execute in user mode where interrupts are blocked, eliminating interrupt-related latency for time-sensitive operations while maintaining system responsiveness for non-critical interrupts.
Solution Approach 2:
The patent implements dynamic interrupt control where the processor can selectively block or allow interrupts based on the current execution context. Atomic instructions dynamically block interrupts during their execution sequence, and the processor transitions between interrupt-blocked and interrupt-enabled states based on the operation being performed, optimizing both responsiveness and latency.
2Ease of operation
If supervisor mode is used to control interrupts, then interrupt control capability is improved, but mode switching overhead increases
Solution Approach 1:
The patent divides interrupt control capabilities between two execution modes: supervisor mode with full interrupt control and user mode with atomic operation capabilities. This segmentation eliminates the need for mode switching when performing atomic operations, as user mode inherently blocks interrupts, thereby reducing overhead while maintaining necessary control capabilities.
Solution Approach 2:
Atomic instructions in user mode automatically block interrupts without requiring external control or mode switching. The interrupt blocking mechanism is self-service, where the atomic instruction sequence inherently prevents interrupt execution, eliminating the overhead associated with supervisor mode transitions while maintaining interrupt control where needed.
3Adaptability or versatility
If interrupts are allowed during multi-byte operations, then system flexibility is improved, but execution reliability deteriorates
Solution Approach 1:
The patent implements dynamic interrupt blocking specific to atomic instruction sequences. During multi-byte operations marked as atomic, interrupts are dynamically blocked to ensure execution reliability. The system flexibly adapts by allowing interrupts during non-atomic operations while blocking them only when necessary for atomicity, maintaining both reliability and flexibility.
Solution Approach 2:
The patent applies preliminary anti-action by proactively blocking interrupts before they can disrupt atomic instruction sequences. The atomic instruction mechanism preemptively prevents interrupt execution during critical multi-byte operations, countacting potential reliability issues before they occur while maintaining system flexibility for non-critical operations.
4Reliability
If atomic operation designation is added to instructions, then execution atomicity is improved, but instruction set complexity increases
Solution Approach 1:
The patent applies local quality by adding atomic operation designation to specific instructions that require atomic execution rather than all instructions. This selective approach improves execution atomicity for critical operations while minimizing instruction set complexity by maintaining standard instruction formats for non-atomic operations.
Solution Approach 2:
The patent implements atomic operation designation through parameter changes in the instruction encoding, such as adding a single bit or opcode variation to indicate atomic execution. This minimal parameter change achieves execution atomicity for designated instructions while keeping the overall instruction set complexity low and maintaining compatibility with existing processor architectures.
Data Source
AI summary
An article of manufacture includes a non-transitory machine-readable medium. The medium includes instructions. The instructions, when read and executed by a processor, cause the processor to identify a first input instruction in a code stream to be executed, determine that the first input instruction includes an atomic operation designation, and selectively block interrupts for a duration of execution of the first input instruction and a second input instruction. The second input instruction is to immediately follow the first input instruction in the code stream.