Distributed real-time operating system providing integrated interrupt management
First Claim
1. An interrupt manager for use with a processor in a distributed control system, the interrupt manager comprising:
- (a) interrupt reception circuitry receiving interrupt signals including a current interrupt;
(b) an interrupt window counter storing an interrupt window indicating time available for processing of interrupts;
(c) a timer refreshing the interrupt window counter at expiration of a window period; and
(e) a masking circuit masking a current interrupt when the interrupt window counter indicates that the processing of the current interrupt would exceed the interrupt window in the current window period.
1 Assignment
0 Petitions
Accused Products
Abstract
An interrupt handler is provided for a real-time control system that prevents interrupts which occur asynchronously with respect to control tasks from upsetting guarantees of timely execution of the control tasks. For interrupts associated with the communication of messages between portions of a control task over the distributed system, the interrupts are converted to proxy tasks that may be scheduled like any task in a multitasked-operated system. More generally, interrupts may be assigned to a predetermined interrupt window being a portion of the total processing bandwidth of the processor. In pre-allocating the processor bandwidth to the control tasks, this interrupt window may be subtracted out thereby guaranteeing adequate bandwidth for both interrupt processing and user tasks.
-
Citations
11 Claims
-
1. An interrupt manager for use with a processor in a distributed control system, the interrupt manager comprising:
-
(a) interrupt reception circuitry receiving interrupt signals including a current interrupt;
(b) an interrupt window counter storing an interrupt window indicating time available for processing of interrupts;
(c) a timer refreshing the interrupt window counter at expiration of a window period; and
(e) a masking circuit masking a current interrupt when the interrupt window counter indicates that the processing of the current interrupt would exceed the interrupt window in the current window period. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
whereby the interrupt processing time is more accurately determined.
-
-
8. The interrupt manager of claim 6 wherein upon completion of the current interrupt, the interrupt manager adds the estimate of the interrupt processing time to the interrupt window and subtracts an actual interrupt processing time from the value of the interrupt window;
whereby later estimates of the interrupt window are more accurate.
-
9. An interrupt manager for use with a processor in a distributed control system, the interrupt manager comprising:
-
(a) a task scheduler receiving tasks and arranging tasks in a queue according to priorities for execution by the processor;
(b) a communication circuit receiving messages having a priority to generate a communications interrupt; and
(c) an interrupt reception circuit communicating with the task scheduler and the communication circuit to receive communication interrupts and to generate corresponding proxy tasks sent to the task scheduler, the proxy task when executed by the processor causing the communication interrupt to be processed as a task, the proxy tasks having the priority of the message associated with their communication interrupt. - View Dependent Claims (10, 11)
-
Specification