Method and apparatus for exception handling in a multi-processing environment

• US 7,519,975 B2
• Filed: 07/24/2006
• Issued: 04/14/2009
• Est. Priority Date: 06/02/2001
• Status: Active Grant

• Current Assignee: Ericsson AB (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Redback Networks Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Lal, Sanjay
• Primary Examiner(s): Patel; Haresh N
• Application Number:
  US11/492,335
• Publication Number:
  US 20060265717A1
• Time in Patent Office: 995 Days
• Field of Search: 719/318, 719310-312, 714 10- 13, 712 10- 22, 712 28- 31, 712/244, 709217-228
• US Class Current: 719/318
• CPC Class Codes: G06F 2209/481 Exception handling
• CPC Class Codes: G06F 9/3861 Recovery, e.g. branch miss-prediction, exception handling error detection or correction G06F11/00
• CPC Class Codes: G06F 9/4812 by interrupt, e.g. masked

Abstract

A method and apparatus for exception handling in a multi-processor environment are described. In an embodiment, a method for handling a number of exceptions within a processor in a multi-processing system includes receiving an exception within the processor, wherein each processor in the multi-processor system shares a same memory. The method also includes executing a number of instructions at an address within a common interrupt handling vector address space of the same memory. The number of instructions cause the processor to determine an identification of the processor based on a query that is internal to the processor. Additionally, the method includes modifying execution flow of the exception to execute an interrupt handler located within one of a number of different interrupt handling vector address spaces.

Claims

1. A network element for routing traffic between networks, compnsing:

a first line card coupled to a first network;

a second line card coupled to a second network different than the first network;

a control card coupled to the first line card and the second line card for routing network traffic between the first and second networks via the first line card and the second line card, the control card including

a plurality of processors including a first processor and a second processor,

a memory including

a common exception handling vector address space shared by the plurality of processors, and

a plurality of exception handling vector address spaces each associated with each of the plurality of processors,

including a first exception and a second exception handling vector address spaces associated with the first and second processors respectively,

a memory controller coupled to the memory and the plurality of processors, wherein the first processor is to execute a first operating system, wherein the first operating system is a real-time operating system to handle routing network traffic, and

wherein the second processor is to execute a second operating system and to execute one or more instructions in the common exception handling vector address space upon receipt of an exception, wherein the second operating system is a non-real-time operating system to handle at least one of provisioning and configuration of the network element wherein the one or more instructions cause the second processor to modify based on an identification of the second processor an execution flow of the exception to execute an interrupt handler located within a respective dedicated interrupt handling vector address spaces associated with the second processor.

2. The network element of claim 1, wherein the first network is a network provider network and the second network is a service provider network.

3. A system comprising:

a plurality of processors to execute different operating systems and to each handle exceptions, wherein at least one of the different operating systems is a real-time operating system to handle routing network traffic and at least one other one of the different operating systems is a non-real-time operating system to handle at least one of provisioning and configuration of a network element;

a memory device to store a common exception handling vector address space, the address space having a separate interrupt handler for each operating system; and

a memory controller coupled to the memory and plurality of processors, wherein upon receiving an exception at one of the plurality of processors, the processor determines a type of the exception and executes instructions within the common exception handling vector address space to determine an identification of the processor based on a value in an internal register and to select an interrupt handler for the operating system of the identified processor.

4. The system of claim 3, wherein the internal register is not dedicated to determining the identification of the one of the plurality of the processors.

5. The system of claim 3, wherein the one of the plurality of processors is to determine the identification of the one of the plurality of the processors during initialization, based on communications with the memory controller.

6. A system to handle exceptions comprising:

a plurality of processors;

a plurality of dissimilar operating systems, wherein each of the plurality of processors executes one of the plurality of dissimilar operating systems, wherein at least some of the plurality of dissimilar operating systems are real-time operating systems to handle routing network traffic and at least some of the plurality of dissimilar operating systems are non-real-time operating systems to handle at least one of provisioning and configuration of a network element;

a memory, wherein the memory is to store a common exception handling vector address space and a plurality of separate interrupt handlers for each of the plurality of dissimilar operating systems; and

a memory controller coupled to the memory and the plurality of processors, wherein upon receiving an exception by one of the plurality of processors, the one of the plurality of processors determines a type of the exception, executes instructions within the common exception handling vector address space, determines an identification of the one of the plurality of processors based on a value stored in an internal register of the one of the plurality of processors, and selects one of a plurality of separate interrupt handlers for the operating system of the identified processor.

7. The system of claim 6, wherein each of the plurality of operating systems is associated with one of the interrupt handling vector address spaces.

8. The system of claim 6, wherein the internal register is not dedicated to determining the identification of the one of the plurality of the processors.

9. The system of claim 6, wherein the one of the plurality of the processors is to determine the identification of the one of the plurality of the processors during initialization, based on communications with the memory controller.

10. A machine storage-readable medium that provides instructions to handle exceptions in a system having a plurality of processors, a plurality of dissimilar operating systems, a memory, and a memory controller coupled to the memory and the plurality of processors, the instructions when executed by a machine, causes the machine to perform operations comprising:

receiving an exception within one of the plurality of processors, wherein each of the plurality of processors execute one of the plurality of dissimilar operating systems, the memory is used to store a common exception handling vector address space and a plurality of separate interrupt handlers for each of the plurality of dissimilar operating systems, the one of the plurality of processors having an internal register, wherein at least some of the plurality of dissimilar operating systems are real-time operating systems to handle routing network traffic and at least some of the plurality of dissimilar operating systems are non-real-time operating systems to handle at least one of provisioning and configuration of a network element;

determining a type of the execution by the one of the plurality of processors;

executing instructions within the common exception handling vector address space by the one of the plurality of processors;

determining, by the one of the plurality of processors, an identification of the one of the plurality of processors based on a value stored in the internal register; and

selecting one of a plurality of separate interrupt handlers for the operating system of the identified processor by the one of the plurality of processors.

11. The machine storage-readable medium of claim 10, wherein the internal register is not dedicated to determining the identification of the one of the plurality of processors.

12. The machine storage-readable medium of claim 10, wherein each of the operating systems is associated with one of the interrupt handling address spaces.

13. The machine storage-readable medium of claim 10, further comprising determining the identification of the one of the plurality of processors during initialization of the one of the plurality of processors, based communications with the memory controller.